Merge pull request #827 from heroku/fix-python-3-5-7

Fix Python 3.5.7
avoid service restart prompt during Dockerfile builds
2026-06-05 23:10:16 +00:00 · 2019-07-17 21:55:48 +02:00 · 2019-07-17 02:22:10 +02:00 · 2019-07-17 01:55:46 +02:00 · 2019-07-17 01:43:54 +02:00 · 2019-06-21 10:43:28 -07:00
159 changed files with 24858 additions and 20114 deletions
@@ -0,0 +1 @@
+* @heroku/languages
@@ -0,0 +1,8 @@
+<!-- Hi and welcome to the Heroku Python buildpack repository!
+
+If you meant to open a PR against a fork instead of upstream, please adjust the base branch:
+https://help.github.com/articles/changing-the-base-branch-of-a-pull-request/
+
+Otherwise thank you in advance for your Pull Request - just remember to
+include as much information as possible to help the reviewers :-)
+-->
@@ -3,3 +3,7 @@ site
 .DS_Store

 /.envrc
+repos/*
+
+#Venv
+buildpack/*
@@ -0,0 +1,5 @@
+repos:
+-   repo: git://github.com/detailyang/pre-commit-shell
+    rev: 1.0.4
+    hooks:
+    - id: shell-lint
@@ -1,23 +1,35 @@
-language: bash
+language: ruby
 dist: trusty
+sudo: required
+rvm:
+- 2.4.4
+before_script:
+  - gem install bundler -v 1.16.2
+  - bundle exec hatchet ci:setup
 jobs:
  include:
-    - stage: "Bash linting (shellcheck)"
-      sudo: false
-      addons:
-        apt:
-          sources:
-          - debian-sid    # Grab shellcheck from the Debian repo (o_O)
-          packages:
-          - shellcheck
-      script: make check
-
-    - stage: "Stack Tests"
-      services: docker
-      env: STACK=heroku-16
-      script: ./tests.sh
-
-    - stage: "Stack Tests"
-      services: docker
-      env: STACK=cedar-14
-      script: ./tests.sh
+  - stage: Bash linting (shellcheck)
+    sudo: false
+    script: make check
+  - stage: Stack Unit Tests
+    services: docker
+    env: STACK=heroku-18
+    script: "./tests.sh"
+  - stage: Stack Unit Tests
+    services: docker
+    env: STACK=heroku-16
+    script: "./tests.sh"
+  - stage: Stack Unit Tests
+    services: docker
+    env: STACK=cedar-14
+    script: "./tests.sh"
+  - stage: Hatchet Integration
+    script: "bundle exec rspec"
+env:
+  global:
+  - HATCHET_RETRIES=3
+  - IS_RUNNING_ON_CI=true
+  - HATCHET_APP_LIMIT=5
+  - HATCHET_DEPLOY_STRATEGY=git
+  - secure: yjtlPE5FbVxTKnjUy/tZUBgSEf4qADD3QOxtgziuid73S0U/1IEXlMGFULsQzIjtlHKmHeywZqpVVEpthIH4RuT7uoX1Pb7SSM/g0T8fT3VoEFbFK1uYl0oZQbUS4Klxv9tPiumj8if3m6ULEGIz1X0wZcMOC0tMLwVCnwmap0E=
+  - secure: ZeFTHWwnpIKE9nAqs88ocmiQh7bKce84lilGm5J23nf3N6V4wNyLwqlkvsM008WGBCaOg9AUx7ZunasT0ANsR5gLP3eV2UUg7ILdRgV2Gy13eNRFheC4PHdN92RqQ3aKoqlIv2K999xlhVjod0NzhkQQXB6PddfQINbuU7ks6As=
@@ -1,5 +1,172 @@
 # Python Buildpack Changelog

+# 154 (2019-07-17)
+
+Fix python 3.5.7 formula actually building 3.7.2
+
+# 153 (2019-06-21)
+
+Hotfix for broken heroku-16 deploys
+
+# 152 (2019-04-04)
+
+Python 3.7.3 now available.
+
+# 151 (2019-03-21)
+
+Python 3.5.7 and 3.4.10 now available on all Heroku stacks.
+
+# 150 (2019-03-13)
+
+Python 2.7.16 now available on all Heroku stacks.
+
+# 149 (2019-03-04)
+
+Hotfix for broken Cedar 14 deploys
+
+# 148 (2019-02-21)
+
+No user facing changes, improving internal metrics
+
+# 147 (2019-02-07)
+
+Python 3.7.2 and 3.6.8 now available on all Heroku stacks.
+
+# 146 (2018-11-11)
+
+Python 3.7.1, 3.6.7, 3.5.6 and 3.4.9 now available on all Heroku stacks.
+
+# 145 (2018-11-08)
+
+Testing and tooling expanded to better support new runtimes
+
+# 144 (2018-10-10)
+
+Switch to cautious upgrade for Pipenv install to ensure the pinned pip version
+is used with Pipenv
+
+# 143 (2018-10-09)
+
+Add support for detecting SLUGIFY_USES_TEXT_UNIDECODE, which is required to
+install Apache Airflow version 1.10 or higher.
+
+# 142 (2018-10-08)
+
+Improvements to Python install messaging
+
+# 139, 140, 141
+
+No user-facing changes, documenting for version clarity
+
+# 138 (2018-08-01)
+
+Use stack image SQLite3 instead of vendoring
+
+# 137 (2018-07-17)
+
+Prevent 3.7.0 from appearing as unsupported in buildpack messaging.
+
+# 136 (2018-06-28)
+
+Upgrade to 3.6.6 and support 3.7.0 on all runtimes.
+
+# 135 (2018-05-29)
+
+Upgrade Pipenv to v2018.5.18.
+
+# 134 (2018-05-02)
+
+Default to 3.6.5, bugfixes.
+
+# 133
+
+Fixes for Pip 10 release.
+
+# 132
+
+Improve pip installation, with the release of v9.0.2.
+
+# 131
+
+Fix bug with pip.
+
+# 130
+
+Better upgrade strategy for pip.
+
+# 129
+
+Don't upgrade pip (from v128).
+
+# 128
+
+Upgrade pip, pin to Pipenv v11.8.2.
+
+# 127
+
+Pin to Pipenv v11.7.1.
+
+# 126
+
+Bugfixes.
+
+# 125
+
+Bugfixes.
+
+# 124
+
+Update buildpack to automatically install `[dev-packages]` during Heroku CI Pipenv builds.
+
+- Skip installs if Pipfile.lock hasn't changed, and uninstall stale dependencies with Pipenv.
+- Set `PYTHONPATH` during collectstatic runs.
+- No longer warn if there is no `Procfile`.
+- Update Pipenv's "3.6" runtime specifier to point to "3.6.4".
+
+# 123
+
+Update gunicorn `init.d` script to allow overrides.
+
+# 122
+
+Update default Python to v3.6.4.
+
+# 121
+
+Update default Python to v3.6.3.
+
+# 120
+
+Use `$ pipenv --deploy`.
+
+# 119
+
+Improvements to Pipenv support, warning on unsupported Python versions.
+
+- We now warn when a user is not using latest 2.x or 3.x Python.
+- Heroku now supports `[requires]` `python_full_version` in addition to `python_version`.
+
+# 118
+
+Improvements to Pipenv support.
+
+# 117
+
+Bug fix.
+
+# 116
+
+Vendoring improvements.
+
+- Geos libraries should work on Heroku-16 now.
+- The libffi/libmemcached vendoring step is now skipped on Heroku-16 (since they are installed in the base image).
+
+# 115
+
+Revert a pull request.
+
+- No longer using `sub_env` for `pip install` step.
+
 # 114

 - Bugfixes.
@@ -8,7 +175,7 @@ Blacklisting `PYTHONHOME` and `PYTHONPATH` for older apps. Upgrades to nltk supp

 # 113

- Updates to Pipenv support.
+Updates to Pipenv support.

 # 112

@@ -22,17 +189,17 @@ Linting, bugfixes.

 # 110

+Update default Python to 3.6.2.
+
+# 109
+
 Update Default Python to 3.6.1, bugfixes.

 - Fixed automatic pip uninstall of dependencies removed from requirements.txt.

-# 109
-
-Fix output for collectstatic step.
-
 # 108

-Updated setuptools.
+Fix output for collectstatic step.

 # 107

@@ -3,7 +3,8 @@ FROM heroku/heroku:16-build
 WORKDIR /app
 ENV WORKSPACE_DIR="/app/builds" \
    S3_BUCKET="lang-python" \
-    S3_PREFIX="heroku-16/"
+    S3_PREFIX="heroku-16/" \
+    DEBIAN_FRONTEND=noninteractive

 RUN apt-get update && apt-get install -y python-pip && rm -rf /var/lib/apt/lists/*

@@ -0,0 +1,14 @@
+FROM heroku/heroku:18-build
+
+WORKDIR /app
+ENV WORKSPACE_DIR="/app/builds" \
+    S3_BUCKET="lang-python" \
+    S3_PREFIX="heroku-18/" \
+    DEBIAN_FRONTEND=noninteractive
+
+RUN apt-get update && apt-get install -y python-pip && rm -rf /var/lib/apt/lists/*
+
+COPY requirements.txt /app/
+RUN pip install --disable-pip-version-check --no-cache-dir -r /app/requirements.txt
+
+COPY . /app
@@ -0,0 +1,6 @@
+source "https://rubygems.org"
+
+gem "rspec"
+gem "heroku_hatchet"
+gem "rspec-retry"
+gem "rake"
@@ -0,0 +1,71 @@
+GEM
+  remote: https://rubygems.org/
+  specs:
+    activesupport (5.2.1)
+      concurrent-ruby (~> 1.0, >= 1.0.2)
+      i18n (>= 0.7, < 2)
+      minitest (~> 5.1)
+      tzinfo (~> 1.1)
+    concurrent-ruby (1.1.3)
+    diff-lcs (1.3)
+    erubis (2.7.0)
+    excon (0.62.0)
+    heroics (0.0.25)
+      erubis (~> 2.0)
+      excon
+      moneta
+      multi_json (>= 1.9.2)
+    heroku_hatchet (4.0.6)
+      excon (~> 0)
+      minitest-retry (~> 0.1.9)
+      platform-api (~> 2)
+      repl_runner (~> 0.0.3)
+      rrrretry (~> 1)
+      thor (~> 0)
+      threaded (~> 0)
+    i18n (1.1.1)
+      concurrent-ruby (~> 1.0)
+    minitest (5.11.3)
+    minitest-retry (0.1.9)
+      minitest (>= 5.0)
+    moneta (1.0.0)
+    multi_json (1.13.1)
+    platform-api (2.2.0)
+      heroics (~> 0.0.25)
+      moneta (~> 1.0.0)
+    rake (12.3.1)
+    repl_runner (0.0.3)
+      activesupport
+    rrrretry (1.0.0)
+    rspec (3.8.0)
+      rspec-core (~> 3.8.0)
+      rspec-expectations (~> 3.8.0)
+      rspec-mocks (~> 3.8.0)
+    rspec-core (3.8.0)
+      rspec-support (~> 3.8.0)
+    rspec-expectations (3.8.1)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.8.0)
+    rspec-mocks (3.8.0)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.8.0)
+    rspec-retry (0.6.1)
+      rspec-core (> 3.3)
+    rspec-support (3.8.0)
+    thor (0.20.3)
+    thread_safe (0.3.6)
+    threaded (0.0.4)
+    tzinfo (1.2.5)
+      thread_safe (~> 0.1)
+
+PLATFORMS
+  ruby
+
+DEPENDENCIES
+  heroku_hatchet
+  rake
+  rspec
+  rspec-retry
+
+BUNDLED WITH
+   1.16.3
@@ -1,11 +1,11 @@
 # These targets are not files
 .PHONY: tests

-test: test-heroku-16
+test: test-heroku-18 test-heroku-16

 check:
-	@shellcheck -x bin/compile bin/detect bin/release bin/test-compile bin/utils bin/warnings
-	@shellcheck -x bin/steps/collectstatic bin/steps/cryptography bin/steps/eggpath-fix  bin/steps/eggpath-fix2 bin/steps/gdal bin/steps/geo-libs bin/steps/mercurial bin/steps/nltk bin/steps/pip-install bin/steps/pip-uninstall bin/steps/pipenv bin/steps/pipenv-python-version bin/steps/pylibmc bin/steps/python
+	@shellcheck -x bin/compile bin/detect bin/release bin/test-compile bin/utils bin/warnings bin/default_pythons
+	@shellcheck -x bin/steps/collectstatic bin/steps/eggpath-fix  bin/steps/eggpath-fix2 bin/steps/gdal bin/steps/geo-libs bin/steps/mercurial bin/steps/nltk bin/steps/pip-install bin/steps/pip-uninstall bin/steps/pipenv bin/steps/pipenv-python-version bin/steps/pylibmc bin/steps/python
 	@shellcheck -x bin/steps/hooks/*

 test-cedar-14:
@@ -18,6 +18,11 @@ test-heroku-16:
 	@docker run -v $(shell pwd):/buildpack:ro --rm -it -e "STACK=heroku-16" heroku/heroku:16-build bash -c 'cp -r /buildpack /buildpack_test; cd /buildpack_test/; test/run;'
 	@echo ""

+test-heroku-18:
+	@echo "Running tests in docker (heroku-18)..."
+	@docker run -v $(shell pwd):/buildpack:ro --rm -it -e "STACK=heroku-18" heroku/heroku:18-build bash -c 'cp -r /buildpack /buildpack_test; cd /buildpack_test/; test/run;'
+	@echo ""
+
 buildenv-heroku-16:
 	@echo "Creating build environment (heroku-16)..."
 	@echo
@@ -0,0 +1,9 @@
+[[source]]
+url = "https://pypi.python.org/simple"
+verify_ssl = true
+name = "pypi"
+
+[dev-packages]
+
+[packages]
+"bob-builder" = "==0.0.13"
@@ -0,0 +1,52 @@
+{
+    "_meta": {
+        "hash": {
+            "sha256": "36d17c46a8b1b844b3cae475f6f42d6c0a9e59b2a9685cbcdc0985656a7a129f"
+        },
+        "host-environment-markers": {
+            "implementation_name": "cpython",
+            "implementation_version": "3.6.3",
+            "os_name": "posix",
+            "platform_machine": "x86_64",
+            "platform_python_implementation": "CPython",
+            "platform_release": "16.7.0",
+            "platform_system": "Darwin",
+            "platform_version": "Darwin Kernel Version 16.7.0: Thu Jun 15 17:36:27 PDT 2017; root:xnu-3789.70.16~2/RELEASE_X86_64",
+            "python_full_version": "3.6.3",
+            "python_version": "3.6",
+            "sys_platform": "darwin"
+        },
+        "pipfile-spec": 6,
+        "requires": {},
+        "sources": [
+            {
+                "name": "pypi",
+                "url": "https://pypi.python.org/simple",
+                "verify_ssl": true
+            }
+        ]
+    },
+    "default": {
+        "bob-builder": {
+            "hashes": [
+                "sha256:b4de49a8e436fcaf82236ea43f78413b4a4c92100726e382ab57b6bdfb38fe64",
+                "sha256:288e3e765c4890fe9a63ae52ac6b4a963c13fe508482c70ff701a5ae21b9a673"
+            ],
+            "version": "==0.0.13"
+        },
+        "boto": {
+            "hashes": [
+                "sha256:13be844158d1bd80a94c972c806ec8381b9ea72035aa06123c5db6bc6a6f3ead",
+                "sha256:deb8925b734b109679e3de65856018996338758f4b916ff4fe7bb62b6d7000d1"
+            ],
+            "version": "==2.48.0"
+        },
+        "docopt": {
+            "hashes": [
+                "sha256:49b3a825280bd66b3aa83585ef59c4a8c82f2c8a522dbe754a8bc8d08c85c491"
+            ],
+            "version": "==0.6.2"
+        }
+    },
+    "develop": {}
+}
@@ -4,36 +4,54 @@

 [![Build Status](https://travis-ci.org/heroku/heroku-buildpack-python.svg?branch=master)](https://travis-ci.org/heroku/heroku-buildpack-python)

-This is the official [Heroku buildpack](https://devcenter.heroku.com/articles/buildpacks) for Python apps, powered by [Pipenv](http://docs.pipenv.org/en/latest/), [pip](https://pip.pypa.io/) and other excellent software.
+This is the official [Heroku buildpack](https://devcenter.heroku.com/articles/buildpacks) for Python apps.

-Recommended web frameworks include **Django** and **Flask**. The recommended webserver is **Gunicorn**. There are no restrictions around what software can be used (as long as it's pip-installable). Web processes must bind to `$PORT`, and only the HTTP protocol is permitted for incoming connections.
+Recommended web frameworks include **Django** and **Flask**, among others. The recommended webserver is **Gunicorn**. There are no restrictions around what software can be used (as long as it's pip-installable). Web processes must bind to `$PORT`, and only the HTTP protocol is permitted for incoming connections.

-Some Python packages with obscure C dependencies are [not compatible](https://devcenter.heroku.com/articles/python-c-deps).
+Python packages with C dependencies that are not [available on the stack image](https://devcenter.heroku.com/articles/stack-packages) are generally not supported, unless `manylinux` wheels are provided by the package maintainers (common). For recommended solutions, check out [this article](https://devcenter.heroku.com/articles/python-c-deps) for more information.

 See it in Action
 ----------------
+```
+$ ls
+my-application		requirements.txt	runtime.txt

-Deploying a Python application couldn't be easier:
+$ git push heroku master
+Counting objects: 4, done.
+Delta compression using up to 8 threads.
+Compressing objects: 100% (2/2), done.
+Writing objects: 100% (4/4), 276 bytes | 276.00 KiB/s, done.
+Total 4 (delta 0), reused 0 (delta 0)
+remote: Compressing source files... done.
+remote: Building source:
+remote:
+remote: -----> Python app detected
+remote: -----> Installing python-3.7.1
+remote: -----> Installing pip
+remote: -----> Installing SQLite3
+remote: -----> Installing requirements with pip
+remote:        Collecting flask (from -r /tmp/build_c2c067ef79ff14c9bf1aed6796f9ed1f/requirements.txt (line 1))
+remote:          Downloading ...
+remote:        Installing collected packages: Werkzeug, click, MarkupSafe, Jinja2, itsdangerous, flask
+remote:        Successfully installed Jinja2-2.10 MarkupSafe-1.1.0 Werkzeug-0.14.1 click-7.0 flask-1.0.2 itsdangerous-1.1.0
+remote:
+remote: -----> Discovering process types
+remote:        Procfile declares types -> (none)
+remote:
+```

-    $ ls
-    Pipfile		Procfile	web.py
+A `requirements.txt` must be present at the root of your application's repository to deploy.

-    $ heroku create --buildpack heroku/python
+To specify your python version, you also need a `runtime.txt` file - unless you are using the default Python runtime version.

-    $ git push heroku master
-    ...
-    -----> Python app detected
-    -----> Installing python-3.6.2
-    -----> Installing pip
-    -----> Installing requirements with latest pipenv...
-           ...
-           Installing dependencies from Pipfile...
-    -----> Discovering process types
-           Procfile declares types -> (none)
+Current default Python Runtime: Python 3.6.7

-A `Pipfile` or `requirements.txt` must be present at the root of your application's repository.
+Alternatively, you can provide a `setup.py` file, or a `Pipfile`. Using `Pipenv` will generate `runtime.txt` based on `python-version` at build time.

-You can also specify the latest production release of this buildpack for upcoming builds of an existing application:
+Specify a Buildpack Version
+---------------------------
+
+You can specify the latest production release of this buildpack for upcoming builds of an existing application:

    $ heroku buildpacks:set heroku/python

@@ -41,14 +59,30 @@ You can also specify the latest production release of this buildpack for upcomin
 Specify a Python Runtime
 ------------------------

-Specific versions of the Python runtime can be specified with a `runtime.txt` file:
+Supported runtime options include:

-    $ cat runtime.txt
-    python-2.7.13
+- `python-3.7.1`
+- `python-3.6.7`
+- `python-2.7.15`

-Runtime options include:
+## Tests

- `python-3.6.2`
- `python-2.7.13`
- `pypy-5.7.1` (unsupported, experimental)
- `pypy3-5.5.1` (unsupported, experimental)
+The buildpack tests use [Docker](https://www.docker.com/) to simulate
+Heroku's [stack images.](https://devcenter.heroku.com/articles/stack)
+
+To run the test suite:
+
+```
+make test
+```
+
+Or to test in a particular stack:
+
+```
+make test-heroku-18
+make test-heroku-16
+```
+
+The tests are run via the vendored
+[shunit2](https://github.com/kward/shunit2)
+test framework.
@@ -0,0 +1 @@
+require 'hatchet/tasks'
@@ -15,61 +15,100 @@
 # Fail fast and fail hard.
 set -eo pipefail

-# Standard Library.
+# Boostrap the Buildpack Standard Library.
 export BPLOG_PREFIX="buildpack.python"
 export BUILDPACK_LOG_FILE=${BUILDPACK_LOG_FILE:-/dev/null}

 [ "$BUILDPACK_XTRACE" ] && set -o xtrace

-# Prepend proper path for virtualenv hackery. This will be deprecated soon.
+# Prepend proper path for old-school virtualenv hackery.
+# This may not be neccessary.
 export PATH=:/usr/local/bin:$PATH

-# Paths.
+# Setup Path variables, for later use in the Buildpack.
 BIN_DIR=$(cd "$(dirname "$0")"; pwd) # absolute path
 ROOT_DIR=$(dirname "$BIN_DIR")
 BUILD_DIR=$1
 CACHE_DIR=$2
 ENV_DIR=$3

+# Export Path variables, for use in sub-scripts.
 export BUILD_DIR CACHE_DIR ENV_DIR

-# Python defaults
-DEFAULT_PYTHON_VERSION="python-3.6.2"
+# Set the Buildpack's internet target for downloading Python distributions.
+# The user can provide BUILDPACK_VENDOR_URL to specify a custom target.
+# Note: this is designed for non-Heroku use, as it does not use the user-provided
+# environment variable mechanism (the ENV_DIR).
+VENDOR_URL="https://lang-python.s3.amazonaws.com/$STACK"
+if [[ -n ${BUILDPACK_VENDOR_URL:-} ]]; then
+    VENDOR_URL="$BUILDPACK_VENDOR_URL"
+fi
+export VENDOR_URL
+
+# Default Python Versions
+# shellcheck source=bin/default_pythons
+source "$BIN_DIR/default_pythons"
+
+# Supported Python Branches
+PY37="python-3.7"
+PY36="python-3.6"
+PY35="python-3.5"
+PY34="python-3.4"
+PY27="python-2.7"
+
+# Which stack is used (for binary downloading), if none is provided (e.g. outside of Heroku)?
 DEFAULT_PYTHON_STACK="cedar-14"
-PIP_UPDATE="9.0.1"
+# If pip doesn't match this version (the version we install), run the installer.
+PIP_UPDATE="9.0.2"

-export DEFAULT_PYTHON_VERSION DEFAULT_PYTHON_STACK PIP_UPDATE
+export DEFAULT_PYTHON_STACK PIP_UPDATE
+export PY37 PY36 PY35 PY27 PY34

-# Common Problem Warnings
+# Common Problem Warnings:
+# This section creates a temporary file in which to stick the output of `pip install`.
+# The `warnings` subscript then greps through this for common problems and guides
+# the user towards resolution of known issues.
 WARNINGS_LOG=$(mktemp)
 export WARNINGS_LOG
 export RECOMMENDED_PYTHON_VERSION=$DEFAULT_PYTHON_VERSION

-# Setup vendored tools and pip-pop (pip-diff)
+# The buildpack ships with a few executable tools (e.g. pip-grep, etc).
+# This installs them into the path, so we can execute them directly.
 export PATH=$PATH:$ROOT_DIR/vendor/:$ROOT_DIR/vendor/pip-pop

-# Support Anvil Build_IDs
+# Set environment variables if they weren't set by the platform.
+# Note: this is legacy, for a deprecated build system known as Anvil.
+# This can likely be removed, with caution.
 [ ! "$SLUG_ID" ] && SLUG_ID="defaultslug"
 [ ! "$REQUEST_ID" ] && REQUEST_ID=$SLUG_ID
 [ ! "$STACK" ] && STACK=$DEFAULT_PYTHON_STACK

-# Sanitizing environment variables.
+# Sanitize externally-provided environment variables:
+# The following environment variables are either problematic or simply unneccessary
+# for the buildpack to have knowledge of, so we unset them, to keep the environment
+# as clean and pristine as possible.
 unset GIT_DIR PYTHONHOME PYTHONPATH
 unset RECEIVE_DATA RUN_KEY BUILD_INFO DEPLOY LOG_TOKEN
 unset CYTOKINE_LOG_FILE GEM_PATH

-# Syntax sugar.
+# Import the utils script, which contains helper functions used throughout the buildpack.
 # shellcheck source=bin/utils
 source "$BIN_DIR/utils"

-# Import collection of warnings.
+# Import the warnings script, which contains the `pip install` user warning mechanisms
+# (mentioned and explained above)
 # shellcheck source=bin/warnings
 source "$BIN_DIR/warnings"

-# we need to put a bunch of symlinks in there later
+# Make the directory in which we will create symlinks from the temporary build directory
+# to `/app`.
+# Symlinks are required, since Python is not a portable installation.
+# More on this topic later.
 mkdir -p /app/.heroku

-# Set up outputs under new context
+# This buildpack programatically generates (or simply copies) a number of files for
+# buildpack machinery: an export script, and a number of `.profile.d` scripts. This
+# section declares the locations of those files and targets.
 PROFILE_PATH="$BUILD_DIR/.profile.d/python.sh"
 EXPORT_PATH="$BIN_DIR/../export"
 GUNICORN_PROFILE_PATH="$BUILD_DIR/.profile.d/python.gunicorn.sh"
@@ -78,49 +117,77 @@ WEB_CONCURRENCY_PROFILE_PATH="$BUILD_DIR/.profile.d/WEB_CONCURRENCY.sh"
 # We'll need to send these statics to other scripts we `source`.
 export BUILD_DIR CACHE_DIR BIN_DIR PROFILE_PATH EXPORT_PATH

-# Prepend proper environment variables for Python use.
+# Python Environment Variables
+# Set Python-specific environment variables, for running Python within the buildpack.
+# Notes on each variable included.
+
+# PATH is relatively obvious, we need to be able to execute 'python'.
 export PATH=/app/.heroku/python/bin:/app/.heroku/vendor/bin:$PATH
+# Tell Python to not buffer it's stdin/stdout.
 export PYTHONUNBUFFERED=1
+# Set the locale to a well-known and expected standard.
 export LANG=en_US.UTF-8
+# `~/.heroku/vendor` is an place where the buildpack may stick pre-build binaries for known
+# C dependencies (e.g. libmemcached on cedar-14). This section configures Python (GCC, more specifically)
+# and pip to automatically include these paths when building binaries.
 export C_INCLUDE_PATH=/app/.heroku/vendor/include:/app/.heroku/python/include:$C_INCLUDE_PATH
 export CPLUS_INCLUDE_PATH=/app/.heroku/vendor/include:/app/.heroku/python/include:$CPLUS_INCLUDE_PATH
 export LIBRARY_PATH=/app/.heroku/vendor/lib:/app/.heroku/python/lib:$LIBRARY_PATH
 export LD_LIBRARY_PATH=/app/.heroku/vendor/lib:/app/.heroku/python/lib:$LD_LIBRARY_PATH
 export PKG_CONFIG_PATH=/app/.heroku/vendor/lib/pkg-config:/app/.heroku/python/lib/pkg-config:$PKG_CONFIG_PATH

+# The Application Code
+# --------------------
+
 # Switch to the repo's context.
 cd "$BUILD_DIR"

-# Warn for lack of Procfile.
-if [[ ! -f Procfile ]]; then
-  puts-warn 'Warning: Your application is missing a Procfile. This file tells Heroku how to run your application.'
-  puts-warn 'Learn more: https://devcenter.heroku.com/articles/procfile'
-fi
+# The Cache
+# ---------

-# Prepare the cache.
+# The workflow for the Python Buildpack's cache is as follows:
+#
+# - `~/.heroku/{known-paths}` are copied from the cache into the slug.
+# - The build is executed, modifying `~/.heroku/{known-paths}`.
+# - Once the build is complete, `~/.heroku/{known-paths}` is copied back into the cache.
+
+# Create the cache directory, if it doesn't exist.
 mkdir -p "$CACHE_DIR"

 # Restore old artifacts from the cache.
 mkdir -p .heroku

+# The Python installation.
 cp -R "$CACHE_DIR/.heroku/python" .heroku/ &> /dev/null || true
+# A plain text file which contains the current stack being used (used for cache busting).
 cp -R "$CACHE_DIR/.heroku/python-stack" .heroku/ &> /dev/null || true
+# A plain text file which contains the current python version being used (used for cache busting).
 cp -R "$CACHE_DIR/.heroku/python-version" .heroku/ &> /dev/null || true
+# A plain text file which contains the current sqlite3 version being used (used for cache busting).
+cp -R "$CACHE_DIR/.heroku/python-sqlite3-version" .heroku/ &> /dev/null || true
+# Any pre-compiled binaries, provided by the buildpack.
 cp -R "$CACHE_DIR/.heroku/vendor" .heroku/ &> /dev/null || true
+# "editable" installations of code repositories, via pip or pipenv.
 if [[ -d "$CACHE_DIR/.heroku/src" ]]; then
  cp -R "$CACHE_DIR/.heroku/src" .heroku/ &> /dev/null || true
 fi

-# Experimental pre_compile hook.
+# The pre_compile hook. Customers rely on this. Don't remove it.
+# This part of the code is used to allow users to customize their build experience
+# without forking the buildpack by providing a `bin/pre_compile` script, which gets
+# run inline with the buildpack automatically.
+
 # shellcheck source=bin/steps/hooks/pre_compile
 source "$BIN_DIR/steps/hooks/pre_compile"

-# Sticky runtimes.
+# Sticky runtimes. If there was a previous build, and it used a given version of Python,
+# continue to use that version of Python in perpituity (warnings will be raised if
+# they are out–of–date).
 if [ -f "$CACHE_DIR/.heroku/python-version" ]; then
  DEFAULT_PYTHON_VERSION=$(cat "$CACHE_DIR/.heroku/python-version")
 fi

-# Stack fallback for non-declared caches.
+# We didn't always record the stack version. This code is in place because of that.
 if [ -f "$CACHE_DIR/.heroku/python-stack" ]; then
  CACHED_PYTHON_STACK=$(cat "$CACHE_DIR/.heroku/python-stack")
 else
@@ -130,17 +197,26 @@ fi
 export CACHED_PYTHON_STACK

 # Pipenv Python version support.
+# Detect the version of Python requested from a Pipfile (e.g. python_version or python_full_version).
+# Convert it to a runtime.txt file.
+
 # shellcheck source=bin/steps/pipenv-python-version
 source "$BIN_DIR/steps/pipenv-python-version"

-# If no runtime given, assume default version.
+# If no runtime was provided by the user, assume the default Python runtime version.
 if [ ! -f runtime.txt ]; then
  echo "$DEFAULT_PYTHON_VERSION" > runtime.txt
 fi

+# Create the directory for .profile.d, if it doesn't exist.
 mkdir -p "$(dirname "$PROFILE_PATH")"
+# Create the directory for editable source code installation, if it doesn't exist.
 mkdir -p /app/.heroku/src

+# On Heroku CI, builds happen in `/app`. Otherwise, on the Heroku platform,
+# they occur in a temp directory. Beacuse Python is not portable, we must create
+# symlinks to emulate that we are operating in `/app` during the build process.
+# This is (hopefully obviously) because apps end up running from `/app` in production.
 if [[ $BUILD_DIR != '/app' ]]; then
    # python expects to reside in /app, so set up symlinks
    # we will not remove these later so subsequent buildpacks can still invoke it
@@ -149,63 +225,89 @@ if [[ $BUILD_DIR != '/app' ]]; then
    # Note: .heroku/src is copied in later.
 fi

-# Install Python.
-let start=$(nowms)
+# Download / Install Python, from pre-build binaries available on Amazon S3.
+# This step also bootstraps pip / setuptools.
+(( start=$(nowms) ))
 # shellcheck source=bin/steps/python
 source "$BIN_DIR/steps/python"
 mtime "python.install.time" "${start}"

-# Pipenv support.
+# Install Pipenv dependencies, if a Pipfile was provided.
 # shellcheck source=bin/steps/pipenv
 source "$BIN_DIR/steps/pipenv"

+# Uninstall removed dependencies with Pip.
+# The buildpack will automatically remove any declared dependencies (in requirements.txt)
+# that were explicitly removed. This machinery is a bit complex, but it is not complicated.
+(( start=$(nowms) ))
+# shellcheck source=bin/steps/pip-uninstall
+source "$BIN_DIR/steps/pip-uninstall"
+mtime "pip.uninstall.time" "${start}"
+
 # If no requirements.txt file given, assume `setup.py develop` is intended.
+# This allows for people to ship a setup.py application to Heroku
+# (which is rare, but I vouch that it should work!)
+
 if [ ! -f requirements.txt ] && [ ! -f Pipfile ]; then
  echo "-e ." > requirements.txt
 fi

 # Fix egg-links.
+# Because we're installing things into a different path than we're running them (temp dir vs app dir),
+# We must re-write all of Python's eggpath links to target the proper directory.
 # shellcheck source=bin/steps/eggpath-fix
 source "$BIN_DIR/steps/eggpath-fix"

 # Mercurial support.
+# If a customer appears to be using mercurial for dependency resolution, we install it first.
+# Note: this only applies to pip, not pipenv. This can likely be removed, over time. Measure it first.
 # shellcheck source=bin/steps/mercurial
 source "$BIN_DIR/steps/mercurial"

 # Pylibmc support.
+# On cedar-14, libmemcached was not available. The buildpack provides its own version, instead.
 # shellcheck source=bin/steps/pylibmc
 source "$BIN_DIR/steps/pylibmc"

-# Libffi support.
-# shellcheck source=bin/steps/cryptography
-source "$BIN_DIR/steps/cryptography"
-
-# Support for Geo libraries.
+# Support for Geo libraries. This is deprecated functionality, only functional on cedar-14.
+# It is undocumented.
 # shellcheck source=bin/steps/geo-libs
 sub_env "$BIN_DIR/steps/geo-libs"

 # GDAL support.
+# This is part of the Geo support.
 # shellcheck source=bin/steps/gdal
 source "$BIN_DIR/steps/gdal"

-# Uninstall removed dependencies with Pip.
-let start=$(nowms)
-# shellcheck source=bin/steps/pip-uninstall
-source "$BIN_DIR/steps/pip-uninstall"
-mtime "pip.uninstall.time" "${start}"
+# SQLite3 support.
+# This sets up and installs sqlite3 dev headers and the sqlite3 binary but not the
+# libsqlite3-0 library since that exists on the stack image.
+# Note: This only applies to Python 2.7.15+ and Python 3.6.6+
+(( start=$(nowms) ))
+# shellcheck source=bin/steps/sqlite3
+source "$BIN_DIR/steps/sqlite3"
+buildpack_sqlite3_install
+mtime "sqlite3.install.time" "${start}"

-# Install dependencies with Pip (where the magic happens).
-let start=$(nowms)
+# pip install
+# -----------
+
+# Install dependencies with pip (where the magic happens).
+(( start=$(nowms) ))
 # shellcheck source=bin/steps/pip-install
 source "$BIN_DIR/steps/pip-install"
 mtime "pip.install.time" "${start}"

 # Support for NLTK corpora.
-let start=$(nowms)
+# Note: this may only work on Python 2.7. I don't think many customers use this functionality,
+# and it should probably be undocumented.
+# (there's an import error on 3.6 that should hopefully be fixed upstream at some point)
+(( start=$(nowms) ))
 sub_env "$BIN_DIR/steps/nltk"
 mtime "nltk.download.time" "${start}"

-# Support for pip install -e.
+# Support for editable installations. Here, we are copying pip–created src directory,
+# and copying it into the proper place (the logical place to do this was early, but it must be done here).
 # In CI, $BUILD_DIR is /app.
 if [[ ! "$BUILD_DIR" == "/app" ]]; then
  rm -fr "$BUILD_DIR/.heroku/src"
@@ -214,28 +316,48 @@ fi


 # Django collectstatic support.
-let start=$(nowms)
+# The buildpack automatically runs collectstatic for Django applications.
+# This is the cause for the majority of build failures on the Python platform.
+# These failures are intentional — if collectstatic (which can be tricky, at times) fails,
+# your build fails.
+(( start=$(nowms) ))
 sub_env "$BIN_DIR/steps/collectstatic"
 mtime "collectstatic.time" "${start}"

-# Create .profile script for application runtime environment variables.
+
+# Progamatically create .profile.d script for application runtime environment variables.
+
+# Set the PATH to include Python / pip / pipenv / etc.
 set_env PATH "\$HOME/.heroku/python/bin:\$PATH"
+# Tell Python to run in unbuffered mode.
 set_env PYTHONUNBUFFERED true
-set_env PYTHONHOME /app/.heroku/python
-
-set_env LIBRARY_PATH "/app/.heroku/vendor/lib:/app/.heroku/python/lib:\$LIBRARY_PATH"
-set_env LD_LIBRARY_PATH "/app/.heroku/vendor/lib:/app/.heroku/python/lib:\$LD_LIBRARY_PATH"
-
+# Tell Python where it lives.
+set_env PYTHONHOME "\$HOME/.heroku/python"
+# Set variables for C libraries.
+set_env LIBRARY_PATH "\$HOME/.heroku/vendor/lib:\$HOME/.heroku/python/lib:\$LIBRARY_PATH"
+set_env LD_LIBRARY_PATH "\$HOME/.heroku/vendor/lib:\$HOME/.heroku/python/lib:\$LD_LIBRARY_PATH"
+# Locale.
 set_default_env LANG en_US.UTF-8
+# The Python hash seed is set to random.
 set_default_env PYTHONHASHSEED random
-set_default_env PYTHONPATH /app/
+# Tell Python to look for Python modules in the /app dir. Don't change this.
+set_default_env PYTHONPATH "\$HOME"
+
+# Python expects to be in /app, if at runtime, it is not, set
+# up symlinks… this can occur when the subdir buildpack is used.
+cat <<EOT >> "$PROFILE_PATH"
+if [[ \$HOME != "/app" ]]; then
+    mkdir -p /app/.heroku
+    ln -nsf "\$HOME/.heroku/python" /app/.heroku/python
+    ln -nsf "\$HOME/.heroku/vendor" /app/.heroku/vendor
+fi
+EOT

 # Install sane-default script for $WEB_CONCURRENCY and $FORWARDED_ALLOW_IPS.
 cp "$ROOT_DIR/vendor/WEB_CONCURRENCY.sh" "$WEB_CONCURRENCY_PROFILE_PATH"
 cp "$ROOT_DIR/vendor/python.gunicorn.sh" "$GUNICORN_PROFILE_PATH"

-
-# Experimental post_compile hook.
+# Experimental post_compile hook. Don't remove this.
 # shellcheck source=bin/steps/hooks/post_compile
 source "$BIN_DIR/steps/hooks/post_compile"

@@ -243,8 +365,7 @@ source "$BIN_DIR/steps/hooks/post_compile"
 # shellcheck source=bin/steps/eggpath-fix2
 source "$BIN_DIR/steps/eggpath-fix2"

-# Store new artifacts in cache.
-
+# Store new artifacts in the cache.
 rm -rf "$CACHE_DIR/.heroku/python"
 rm -rf "$CACHE_DIR/.heroku/python-version"
 rm -rf "$CACHE_DIR/.heroku/python-stack"
@@ -0,0 +1,10 @@
+#!/usr/bin/env bash
+
+DEFAULT_PYTHON_VERSION="python-3.6.8"
+LATEST_36="python-3.6.8"
+LATEST_37="python-3.7.3"
+LATEST_35="python-3.5.7"
+LATEST_34="python-3.4.10"
+LATEST_27="python-2.7.16"
+
+export DEFAULT_PYTHON_VERSION LATEST_37 LATEST_36 LATEST_35 LATEST_34 LATEST_27
@@ -11,7 +11,7 @@
 #   - $DEBUG_COLLECTSTATIC: upon failure, print out environment variables.

 # shellcheck source=bin/utils
-source $BIN_DIR/utils
+source "$BIN_DIR/utils"

 # Location of 'manage.py', if it exists.
 MANAGE_FILE=$(find . -maxdepth 3 -type f -name 'manage.py' -printf '%d\t%P\n' | sort -nk1 | cut -f2 | head -1)
@@ -30,7 +30,13 @@ if [ ! "$DISABLE_COLLECTSTATIC" ] && [ -f "$MANAGE_FILE" ] && [ "$DJANGO_INSTALL
    puts-step "$ python $MANAGE_FILE collectstatic --noinput"

    # Run collectstatic, cleanup some of the noisy output.
-    python "$MANAGE_FILE" collectstatic --noinput --traceback 2>&1 | sed '/^Post-processed/d;/^Copying/d;/^$/d' | indent
+    PYTHONPATH=${PYTHONPATH:-.}
+    export PYTHONPATH
+
+    # Create a temporary file for collecting the collectstaic logs.
+    COLLECTSTATIC_LOG=$(mktemp)
+
+    python "$MANAGE_FILE" collectstatic --noinput --traceback 2>&1 | tee "$COLLECTSTATIC_LOG" | sed '/^Post-processed/d;/^Copying/d;/^$/d' | indent
    COLLECTSTATIC_STATUS="${PIPESTATUS[0]}"

    set -e
@@ -38,6 +44,22 @@ if [ ! "$DISABLE_COLLECTSTATIC" ] && [ -f "$MANAGE_FILE" ] && [ "$DJANGO_INSTALL
    # Display a warning if collectstatic failed.
    [ "$COLLECTSTATIC_STATUS" -ne 0 ] && {

+        if grep -q 'SyntaxError' "$COLLECTSTATIC_LOG"; then
+            mcount "failure.collectstatic.syntax-error"
+
+        elif grep -q 'ImproperlyConfigured' "$COLLECTSTATIC_LOG"; then
+            mcount "failure.collectstatic.improper-configuration"
+
+        elif grep -q 'The CSS file' "$COLLECTSTATIC_LOG"; then
+            mcount "failure.collectstatic.fancy-references"
+
+        elif grep -q 'OSError' "$COLLECTSTATIC_LOG"; then
+            mcount "failure.collectstatic.missing-file"
+
+        else
+            mcount "failure.collectstatic.other"
+        fi
+
        echo
        echo " !     Error while running '$ python $MANAGE_FILE collectstatic --noinput'."
        echo "       See traceback above for details."
@@ -1,33 +0,0 @@
-#!/usr/bin/env bash
-
-# This script serves as the Cryptography build step of the
-# [**Python Buildpack**](https://github.com/heroku/heroku-buildpack-python)
-# compiler.
-#
-# A [buildpack](https://devcenter.heroku.com/articles/buildpacks) is an
-# adapter between a Python application and Heroku's runtime.
-#
-# This script is invoked by [`bin/compile`](/).
-
-# The location of the pre-compiled libffi binary.
-VENDORED_LIBFFI="https://lang-python.s3.amazonaws.com/$STACK/libraries/vendor/libffi.tar.gz"
-
-PKG_CONFIG_PATH="/app/.heroku/vendor/lib/pkgconfig:$PKG_CONFIG_PATH"
-
-# Syntax sugar.
-# shellcheck source=bin/utils
-source "$BIN_DIR/utils"
-
-# If a package using cffi exists within requirements, use vendored libffi.
-if (pip-grep -s requirements.txt argon2-cffi bcrypt cffi cryptography django[argon2] Django[argon2] django[bcrypt] Django[bcrypt] PyNaCl pyOpenSSL PyOpenSSL requests[security] misaka &> /dev/null) then
-
-  if [ ! -d ".heroku/vendor/lib/libffi-3.1" ]; then
-    echo "-----> Noticed cffi. Bootstrapping libffi."
-    mkdir -p .heroku/vendor
-    # Download and extract libffi into target vendor directory.
-    curl "$VENDORED_LIBFFI" -s | tar zxv -C .heroku/vendor &> /dev/null
-  fi
-
-  LIBFFI=$(pwd)/vendor
-  export LIBFFI
-fi
@@ -10,7 +10,7 @@
 # This script is invoked by [`bin/compile`](/).

 # The location of the pre-compiled cryptography binary.
-VENDORED_GDAL="https://lang-python.s3.amazonaws.com/$STACK/libraries/vendor/gdal.tar.gz"
+VENDORED_GDAL="${VENDOR_URL}/libraries/vendor/gdal.tar.gz"

 PKG_CONFIG_PATH="/app/.heroku/vendor/lib/pkgconfig:$PKG_CONFIG_PATH"

@@ -26,9 +26,9 @@ if (pip-grep -s requirements.txt GDAL gdal pygdal &> /dev/null) then
    mkdir -p .heroku/vendor
    # Download and extract cryptography into target vendor directory.
    curl "$VENDORED_GDAL" -s | tar zxv -C .heroku/vendor &> /dev/null
+    mcount "steps.vendor.gdal"
  fi

  GDAL=$(pwd)/vendor
  export GDAL
 fi
-
@@ -10,9 +10,9 @@
 # This script is invoked by [`bin/compile`](/).

 # The location of the pre-compiled cryptography binary.
-VENDORED_GDAL="https://lang-python.s3.amazonaws.com/$STACK/libraries/vendor/gdal.tar.gz"
-VENDORED_GEOS="https://lang-python.s3.amazonaws.com/$STACK/libraries/vendor/geos.tar.gz"
-VENDORED_PROJ="https://lang-python.s3.amazonaws.com/$STACK/libraries/vendor/proj.tar.gz"
+VENDORED_GDAL="${VENDOR_URL}/libraries/vendor/gdal.tar.gz"
+VENDORED_GEOS="${VENDOR_URL}/libraries/vendor/geos.tar.gz"
+VENDORED_PROJ="${VENDOR_URL}/libraries/vendor/proj.tar.gz"

 PKG_CONFIG_PATH="/app/.heroku/vendor/lib/pkgconfig:$PKG_CONFIG_PATH"

@@ -22,6 +22,7 @@ source "$BIN_DIR/utils"

 # If GDAL exists within requirements, use vendored gdal.
 if [[ "$BUILD_WITH_GEO_LIBRARIES" ]]; then
+  mcount "buildvar.BUILD_WITH_GEO_LIBRARIES"

  if [ ! -f ".heroku/vendor/bin/proj" ]; then
    echo "-----> Bootstrapping gdal, geos, proj."
@@ -30,9 +31,22 @@ if [[ "$BUILD_WITH_GEO_LIBRARIES" ]]; then
    curl "$VENDORED_GDAL" -s | tar zxv -C .heroku/vendor &> /dev/null
    curl "$VENDORED_GEOS" -s | tar zxv -C .heroku/vendor &> /dev/null
    curl "$VENDORED_PROJ" -s | tar zxv -C .heroku/vendor &> /dev/null
+
+    mcount "steps.vendor.geo_libs"
+    # Copy libjasper from build image to slug.
+    if [[ "$STACK" == "heroku-16" ]]; then
+      cp /usr/lib/x86_64-linux-gnu/libjasper.so* ".heroku/vendor/lib/."
+      mcount "steps.vendor.libjasper"
+    fi
+
  fi

  GDAL=$(pwd)/vendor
  export GDAL
+  # set path for post_compile hooks
+  export GDAL_LIBRARY_PATH="$BUILD_DIR/.heroku/vendor/lib/libgdal.so"
+  export GEOS_LIBRARY_PATH="$BUILD_DIR/.heroku/vendor/lib/libgeos_c.so"
+  # set path for runtime environmeht
+  set_env GDAL_LIBRARY_PATH "/app/.heroku/vendor/lib/libgdal.so"
+  set_env GEOS_LIBRARY_PATH "/app/.heroku/vendor/lib/libgeos_c.so"
 fi
-
@@ -1,6 +1,9 @@
 #!/usr/bin/env bash

 # Install Mercurial if it appears to be required.
-if (grep -Fiq "hg+" requirements.txt) then
-    /app/.heroku/python/bin/pip install  mercurial | cleanup | indent
+if [[ -f "requirements.txt" ]]; then
+	if (grep -Fiq "hg+" requirements.txt) then
+		/app/.heroku/python/bin/pip install  mercurial | cleanup | indent
+		mcount "steps.mercurial"
+	fi
 fi
@@ -15,7 +15,7 @@ source "$BIN_DIR/utils"

 # Check that nltk was installed by pip, otherwise obviously not needed
 if sp-grep -s nltk; then
-    puts-step "Downloading NLTK corpora..."
+    puts-step "Downloading NLTK corpora…"

    nltk_packages_definition="$BUILD_DIR/nltk.txt"

@@ -27,6 +27,8 @@ if sp-grep -s nltk; then
        python -m nltk.downloader -d "$BUILD_DIR/.heroku/python/nltk_data" "${nltk_packages[@]}" | indent
        set_env NLTK_DATA "/app/.heroku/python/nltk_data"

+        mcount "buildvar.NLTK_PACKAGES_DEFINITION"
+        mcount "steps.nltk"
    else
        puts-warn "'nltk.txt' not found, not downloading any corpora"
        puts-warn "Learn more: https://devcenter.heroku.com/articles/python-nltk"
@@ -1,28 +1,68 @@
 #!/usr/bin/env bash

+# shellcheck source=bin/utils
+source "$BIN_DIR/utils"
+
 if [ ! "$SKIP_PIP_INSTALL" ]; then

    # Install dependencies with Pip.
    puts-step "Installing requirements with pip"

-    set +e
-    BLACKLIST='PYTHONHOME|PYTHONPATH'
-    export BLACKLIST
+    # Set Pip env vars
+    # This reads certain environment variables set on the Heroku app config
+    # and makes them accessible to the pip install process.
+    #
+    # PIP_EXTRA_INDEX_URL allows for an alternate pypi URL to be used.
+    if [[ -r "$ENV_DIR/PIP_EXTRA_INDEX_URL" ]]; then
+        PIP_EXTRA_INDEX_URL="$(cat "$ENV_DIR/PIP_EXTRA_INDEX_URL")"
+        export PIP_EXTRA_INDEX_URL
+        mcount "buildvar.PIP_EXTRA_INDEX_URL"
+    fi

-    sub_env /app/.heroku/python/bin/pip install -r "$BUILD_DIR/requirements.txt" --exists-action=w --src=/app/.heroku/src --disable-pip-version-check --no-cache-dir 2>&1 | tee "$WARNINGS_LOG" | cleanup | indent
+    set +e
+
+    # Set SLUGIFY_USES_TEXT_UNIDECODE, required for Airflow versions >=1.10
+    if [[ -r "$ENV_DIR/SLUGIFY_USES_TEXT_UNIDECODE" ]]; then
+        SLUGIFY_USES_TEXT_UNIDECODE="$(cat "$ENV_DIR/SLUGIFY_USES_TEXT_UNIDECODE")"
+        export SLUGIFY_USES_TEXT_UNIDECODE
+        mcount "buildvar.SLUGIFY_USES_TEXT_UNIDECODE"
+    fi
+
+    set +e
+
+    # Measure that we're using pip.
+    mcount "tool.pip"
+
+    # Count expected build failures.
+    if grep -q '==0.0.0' requirements.txt; then
+        mcount "failure.none-version"
+    fi
+
+    if [ ! -f "$BUILD_DIR/.heroku/python/bin/pip" ]; then
+        exit 1
+    fi
+    /app/.heroku/python/bin/pip install -r "$BUILD_DIR/requirements.txt" --exists-action=w --src=/app/.heroku/src --disable-pip-version-check --no-cache-dir 2>&1 | tee "$WARNINGS_LOG" | cleanup | indent
    PIP_STATUS="${PIPESTATUS[0]}"
    set -e

    show-warnings

    if [[ ! $PIP_STATUS -eq 0 ]]; then
+        mcount "failure.pip-install"
        exit 1
    fi

-
    # Smart Requirements handling
    cp requirements.txt .heroku/python/requirements-declared.txt
    /app/.heroku/python/bin/pip freeze --disable-pip-version-check > .heroku/python/requirements-installed.txt

    echo
+
+    # Install test dependencies, for CI.
+    if [ "$INSTALL_TEST" ]; then
+        if [[ -f "$1/requirements-test.txt" ]]; then
+            puts-step "Installing test dependencies…"
+            /app/.heroku/python/bin/pip install -r "$1/requirements-test.txt" --exists-action=w --src=./.heroku/src --disable-pip-version-check --no-cache-dir 2>&1 | cleanup | indent
+        fi
+    fi
 fi
@@ -2,19 +2,27 @@

 set +e
 # Install dependencies with Pip.
+# shellcheck source=bin/utils
+source "$BIN_DIR/utils"

-if [[ -f .heroku/python/requirements-declared.txt ]]; then
+if [ ! "$SKIP_PIP_INSTALL" ]; then

-  cp .heroku/python/requirements-declared.txt requirements-declared.txt
+  if [[ -f .heroku/python/requirements-declared.txt ]]; then

-  pip-diff --stale requirements-declared.txt requirements.txt --exclude setuptools pip wheel > .heroku/python/requirements-stale.txt
+    cp .heroku/python/requirements-declared.txt requirements-declared.txt

-  rm -fr requirements-declared.txt

-  if [[ -s .heroku/python/requirements-stale.txt ]]; then
-    puts-step "Uninstalling stale dependencies"
-    /app/.heroku/python/bin/pip uninstall -r .heroku/python/requirements-stale.txt -y --exists-action=w | cleanup | indent
+    if ! pip-diff --stale requirements-declared.txt requirements.txt --exclude setuptools pip wheel > .heroku/python/requirements-stale.txt; then
+      mount "failure.bad-requirements"
+    fi
+
+    rm -fr requirements-declared.txt
+
+    if [[ -s .heroku/python/requirements-stale.txt ]]; then
+      puts-step "Uninstalling stale dependencies"
+      /app/.heroku/python/bin/pip uninstall -r .heroku/python/requirements-stale.txt -y --exists-action=w --disable-pip-version-check | cleanup | indent
+    fi
  fi
-fi

+fi
 set -e
@@ -1,21 +1,86 @@
 #!/usr/bin/env bash

-# Pipenv support (Generate requriements.txt with pipenv).
-if [[ -f Pipfile ]]; then
-    if [[ ! -f requirements.txt ]]; then
-        puts-step "Installing requirements with latest pipenv..."
+# export CLINT_FORCE_COLOR=1
+# export PIPENV_FORCE_COLOR=1
+# shellcheck source=bin/utils
+source "$BIN_DIR/utils"
+set -e

-        # Install pipenv.
-        /app/.heroku/python/bin/pip install pipenv --upgrade &> /dev/null
+if [[ -f Pipfile.lock ]]; then
+    if [[ -f .heroku/python/Pipfile.lock.sha256 ]]; then
+        if [[ $(openssl dgst -sha256 Pipfile.lock) == $(cat .heroku/python/Pipfile.lock.sha256) ]]; then
+            # Measure that we're using Pipenv.
+            mcount "tool.pipenv"

-        # Install the dependencies.
-        /app/.heroku/python/bin/pipenv install --system --skip-lock 2>&1 | indent
+            # Don't skip installation of there are git deps.
+            if ! grep -q 'git' Pipfile.lock; then
+                echo "Skipping installation, as Pipfile.lock hasn't changed since last deploy." | indent
+
+                mcount "tool.pipenv"
+                export SKIP_PIPENV_INSTALL=1
+                export SKIP_PIP_INSTALL=1
+            fi
+        fi
+    fi
+fi
+
+
+if [ ! "$SKIP_PIPENV_INSTALL" ]; then
+    # Pipenv support (Generate requriements.txt with pipenv).
+    if [[ -f Pipfile ]]; then
+        # Measure that we're using Pipenv.
+        mcount "tool.pipenv"

        # Skip pip install, later.
        export SKIP_PIP_INSTALL=1

-        # Pip freeze, for compatibility.
-        /app/.heroku/python/bin/pip freeze > requirements.txt
+        # Set Pip env vars
+        # This reads certain environment variables set on the Heroku app config
+        # and makes them accessible to the pip install process.
+        #
+        # PIP_EXTRA_INDEX_URL allows for an alternate pypi URL to be used.
+        if [[ -r "$ENV_DIR/PIP_EXTRA_INDEX_URL" ]]; then
+            PIP_EXTRA_INDEX_URL="$(cat "$ENV_DIR/PIP_EXTRA_INDEX_URL")"
+            export PIP_EXTRA_INDEX_URL
+            mcount "buildvar.PIP_EXTRA_INDEX_URL"
+        fi

+        # Set SLUGIFY_USES_TEXT_UNIDECODE, required for Airflow versions >=1.10
+        if [[ -r "$ENV_DIR/SLUGIFY_USES_TEXT_UNIDECODE" ]]; then
+            SLUGIFY_USES_TEXT_UNIDECODE="$(cat "$ENV_DIR/SLUGIFY_USES_TEXT_UNIDECODE")"
+            export SLUGIFY_USES_TEXT_UNIDECODE
+            mcount "buildvar.SLUGIFY_USES_TEXT_UNIDECODE"
+        fi
+
+        export PIPENV_VERSION="2018.5.18"
+
+        # Install pipenv.
+        # Due to weird old pip behavior and pipenv behavior, pipenv upgrades pip
+        # to latest if only --upgrade is specified. Specify upgrade strategy to
+        # avoid this eager behavior.
+        /app/.heroku/python/bin/pip install pipenv==$PIPENV_VERSION --upgrade --upgrade-strategy only-if-needed &> /dev/null
+
+        # Install the dependencies.
+        if [[ ! -f Pipfile.lock ]]; then
+            puts-step "Installing dependencies with Pipenv $PIPENV_VERSION…"
+            /app/.heroku/python/bin/pipenv install --system --skip-lock 2>&1 | indent
+        else
+            pipenv-to-pip Pipfile.lock > requirements.txt
+            "$BIN_DIR/steps/pip-uninstall"
+            cp requirements.txt .heroku/python/requirements-declared.txt
+            openssl dgst -sha256 Pipfile.lock > .heroku/python/Pipfile.lock.sha256
+
+            puts-step "Installing dependencies with Pipenv $PIPENV_VERSION…"
+            /app/.heroku/python/bin/pipenv install --system --deploy 2>&1 | indent
+        fi
+
+        # Install the test dependencies, for CI.
+        if [ "$INSTALL_TEST" ]; then
+            puts-step "Installing test dependencies…"
+            /app/.heroku/python/bin/pipenv install --dev --system --deploy 2>&1 | cleanup | indent
+        fi
    fi
+else
+    export SKIP_PIP_INSTALL=1
+    pipenv-to-pip Pipfile.lock > requirements.txt
 fi
@@ -6,20 +6,30 @@ if [[ -f $BUILD_DIR/Pipfile ]]; then

    if [[ ! -f $BUILD_DIR/runtime.txt ]]; then
        if [[ ! -f $BUILD_DIR/Pipfile.lock ]]; then
-            puts-warn "No 'pipfile.lock' found! We recommend you commit this into your repository."
+            puts-warn "No 'Pipfile.lock' found! We recommend you commit this into your repository."
        fi
        if [[ -f $BUILD_DIR/Pipfile.lock ]]; then
            set +e
-            PYTHON=$(jq -r '._meta.requires.python_version' "$BUILD_DIR/Pipfile.lock")
+            PYTHON=$(jq -r '._meta.requires.python_full_version' "$BUILD_DIR/Pipfile.lock")
+            if [[ "$PYTHON" != "null" ]]; then
+                echo "python-$PYTHON" > "$BUILD_DIR/runtime.txt"
+            fi
            set -e

-            if [ "$PYTHON" = 2.7 ]; then
-                echo "python-2.7.13" > "$BUILD_DIR/runtime.txt"
-            fi
-            if [ "$PYTHON" = 3.6 ]; then
-                echo "python-3.6.2" > "$BUILD_DIR/runtime.txt"
+            if [[ "$PYTHON" == "null" ]]; then
+                PYTHON=$(jq -r '._meta.requires.python_version' "$BUILD_DIR/Pipfile.lock")
+                if [ "$PYTHON" = 2.7 ]; then
+                    echo "$LATEST_27" > "$BUILD_DIR/runtime.txt"
+                fi
+                if [ "$PYTHON" = 3.6 ]; then
+                    echo "$LATEST_36" > "$BUILD_DIR/runtime.txt"
+                fi
+                if [ "$PYTHON" = 3.7 ]; then
+                    echo "$LATEST_37" > "$BUILD_DIR/runtime.txt"
+                fi
            fi
+
+
        fi
    fi
 fi
-
@@ -9,14 +9,18 @@
 #
 # This script is invoked by [`bin/compile`](/).

+if [[ "$STACK" != "cedar-14" ]]; then
+    # libmemcached is pre-installed in the stack image so there is no need to vendor it.
+    return 0
+fi
+
 # The location of the pre-compiled libmemcached binary.
-VENDORED_MEMCACHED="https://lang-python.s3.amazonaws.com/$STACK/libraries/vendor/libmemcache.tar.gz"
+VENDORED_MEMCACHED="${VENDOR_URL}/libraries/vendor/libmemcache.tar.gz"

 # Syntax sugar.
 # shellcheck source=bin/utils
 source "$BIN_DIR/utils"

-
 # If pylibmc exists within requirements, use vendored libmemcached.
 if (pip-grep -s requirements.txt pylibmc &> /dev/null) then

@@ -25,6 +29,7 @@ if (pip-grep -s requirements.txt pylibmc &> /dev/null) then
    mkdir -p .heroku/vendor
    # Download and extract libmemcached into target vendor directory.
    curl "$VENDORED_MEMCACHED" -s | tar zxv -C .heroku/vendor &> /dev/null
+    mcount "steps.vendor.pylibmc"
  fi

  LIBMEMCACHED=$(pwd)/vendor
@@ -4,9 +4,65 @@ set +e
 runtime-fixer runtime.txt
 PYTHON_VERSION=$(cat runtime.txt)

+# The location of the pre-compiled python binary.
+VENDORED_PYTHON="${VENDOR_URL}/runtimes/$PYTHON_VERSION.tar.gz"
+
+SECURITY_UPDATE="Python has released a security update! Please consider upgrading to"
+
+# check if runtime exists
+if curl --output /dev/null --silent --head --fail "$VENDORED_PYTHON"; then
+  if [[ "$PYTHON_VERSION" == $PY37* ]]; then
+    # do things to alert the user of security release available
+    if [ "$PYTHON_VERSION" != "$LATEST_37" ]; then
+      puts-warn "$SECURITY_UPDATE" "$LATEST_37"
+      echo "       Learn More: https://devcenter.heroku.com/articles/python-runtimes"
+    fi
+  fi
+  if [[ "$PYTHON_VERSION" == $PY36* ]]; then
+    # security update note
+    if [ "$PYTHON_VERSION" != "$LATEST_36" ]; then
+      puts-warn "$SECURITY_UPDATE" "$LATEST_36"
+      echo "       Learn More: https://devcenter.heroku.com/articles/python-runtimes"
+    fi
+  fi
+  if [[ "$PYTHON_VERSION" == $PY35* ]]; then
+    # security update note
+    if [ "$PYTHON_VERSION" != "$LATEST_35" ]; then
+      puts-warn "$SECURITY_UPDATE" "$LATEST_35"
+      echo "       Learn More: https://devcenter.heroku.com/articles/python-runtimes"
+    fi
+  fi
+  if [[ "$PYTHON_VERSION" == $PY34* ]]; then
+    # security update note
+    if [ "$PYTHON_VERSION" != "$LATEST_34" ]; then
+      puts-warn "$SECURITY_UPDATE" "$LATEST_34"
+      echo "       Learn More: https://devcenter.heroku.com/articles/python-runtimes"
+    fi
+  fi
+  if [[ "$PYTHON_VERSION" == $PY27* ]]; then
+    # security update note
+    if [ "$PYTHON_VERSION" != "$LATEST_27" ]; then
+      puts-warn "$SECURITY_UPDATE" "$LATEST_27"
+      echo "       Learn More: https://devcenter.heroku.com/articles/python-runtimes"
+    fi
+  fi
+else
+  puts-warn "Requested runtime ($PYTHON_VERSION) is not available for this stack ($STACK)."
+  puts-warn "Aborting.  More info: https://devcenter.heroku.com/articles/python-support"
+  exit 1
+fi
+
 if [[ "$STACK" != "$CACHED_PYTHON_STACK" ]]; then
    puts-step "Stack has changed from $CACHED_PYTHON_STACK to $STACK, clearing cache"
-    rm -fr .heroku/python-stack .heroku/python-version .heroku/python .heroku/vendor
+    rm -fr .heroku/python-stack .heroku/python-version .heroku/python .heroku/vendor .heroku/python .heroku/python-sqlite3-version
+fi
+
+# need to clear the cache for first time installing SQLite3,
+# since the version is changing and could lead to runtime errors
+# with compiled extensions.
+if [ -d .heroku/python ] && [ ! -f .heroku/python-sqlite3-version ] && python_sqlite3_check "$PYTHON_VERSION"; then
+  puts-step "Need to update SQLite3, clearing cache"
+  rm -fr .heroku/python-stack .heroku/python-version .heroku/python .heroku/vendor
 fi

 if [ -f .heroku/python-version ]; then
@@ -18,6 +74,7 @@ if [ -f .heroku/python-version ]; then
  fi
 fi

+
 if [ ! "$SKIP_INSTALL" ]; then
    puts-step "Installing $PYTHON_VERSION"

@@ -26,7 +83,7 @@ if [ ! "$SKIP_INSTALL" ]; then

    mcount "version.python.$PYTHON_VERSION"

-    if ! curl "https://lang-python.s3.amazonaws.com/$STACK/runtimes/$PYTHON_VERSION.tar.gz" -s | tar zxv -C .heroku/python &> /dev/null; then
+    if ! curl "${VENDORED_PYTHON}" -s | tar zxv -C .heroku/python &> /dev/null; then
      puts-warn "Requested runtime ($PYTHON_VERSION) is not available for this stack ($STACK)."
      puts-warn "Aborting.  More info: https://devcenter.heroku.com/articles/python-support"
      exit 1
@@ -40,17 +97,18 @@ if [ ! "$SKIP_INSTALL" ]; then
  hash -r
 fi

+
 # If Pip isn't up to date:
 if [ "$FRESH_PYTHON" ] || [[ ! $(pip --version) == *$PIP_UPDATE* ]]; then

  puts-step "Installing pip"

  # Remove old installations.
-  rm -fr /app/.heroku/python/lib/python2.7/site-packages/pip-*
-  rm -fr /app/.heroku/python/lib/python2.7/site-packages/setuptools-*
-
-  /app/.heroku/python/bin/python "$ROOT_DIR/vendor/get-pip.py" &> /dev/null
+  rm -fr /app/.heroku/python/lib/python*/site-packages/pip-*
+  rm -fr /app/.heroku/python/lib/python*/site-packages/setuptools-*

+  /app/.heroku/python/bin/python "$ROOT_DIR/vendor/get-pip.py" pip=="$PIP_UPDATE" &> /dev/null
+  /app/.heroku/python/bin/pip install "$ROOT_DIR/vendor/setuptools-39.0.1-py2.py3-none-any.whl" &> /dev/null
 fi

 set -e
@@ -0,0 +1,93 @@
+#!/usr/bin/env bash
+
+# shellcheck source=bin/utils
+source "$BIN_DIR/utils"
+
+sqlite3_version() {
+  if [ "$STACK" = "cedar-14" ]; then
+    SQLITE3_VERSION="3.8.2-1ubuntu2.2"
+  elif [ "$STACK" = "heroku-16" ]; then
+    SQLITE3_VERSION="3.11.0-1ubuntu1.2"
+  else
+    SQLITE3_VERSION=${SQLITE3_VERSION:-$(dpkg -s libsqlite3-0 | grep Version | sed 's/Version: //')}
+  fi
+
+  export SQLITE3_VERSION
+}
+
+sqlite3_install() {
+  HEROKU_PYTHON_DIR="$1"
+  SQLITE3_VERSION="$2"
+  HEADERS_ONLY="$3"
+
+  mkdir -p "$HEROKU_PYTHON_DIR"
+
+  APT_CACHE_DIR="$HEROKU_PYTHON_DIR/apt/cache"
+  APT_STATE_DIR="$HEROKU_PYTHON_DIR/apt/state"
+
+  mkdir -p "$APT_CACHE_DIR/archives/partial"
+  mkdir -p "$APT_STATE_DIR/lists/partial"
+
+  APT_OPTIONS="-o debug::nolocking=true"
+  APT_OPTIONS="$APT_OPTIONS -o dir::cache=$APT_CACHE_DIR"
+  APT_OPTIONS="$APT_OPTIONS -o dir::state=$APT_STATE_DIR"
+  APT_OPTIONS="$APT_OPTIONS -o dir::etc::sourcelist=/etc/apt/sources.list"
+
+  apt-get $APT_OPTIONS update > /dev/null 2>&1
+  if [ -z "$HEADERS_ONLY" ]; then
+    apt-get $APT_OPTIONS -y -d --reinstall install libsqlite3-dev="$SQLITE3_VERSION" sqlite3="$SQLITE3_VERSION" > /dev/null 2>&1
+  else
+    apt-get $APT_OPTIONS -y -d --reinstall install libsqlite3-dev="$SQLITE3_VERSION"
+  fi
+
+  find "$APT_CACHE_DIR/archives/" -name "*.deb" -exec dpkg -x {} "$HEROKU_PYTHON_DIR/sqlite3/" \;
+
+  mkdir -p "$HEROKU_PYTHON_DIR/include"
+  mkdir -p "$HEROKU_PYTHON_DIR/lib"
+
+  # remove old sqlite3 libraries/binaries
+  find "$HEROKU_PYTHON_DIR/include/" -name "sqlite3*.h" -exec rm -f {} \;
+  find "$HEROKU_PYTHON_DIR/lib/" -name "libsqlite3.*" -exec rm -f {} \;
+  rm -f "$HEROKU_PYTHON_DIR/lib/pkgconfig/sqlite3.pc"
+  rm -f "$HEROKU_PYTHON_DIR/bin/sqlite3"
+
+  # copy over sqlite3 headers & bins and setup linking against the stack image library
+  mv "$HEROKU_PYTHON_DIR/sqlite3/usr/include/"* "$HEROKU_PYTHON_DIR/include/"
+  mv "$HEROKU_PYTHON_DIR/sqlite3/usr/lib/x86_64-linux-gnu"/libsqlite3.*a "$HEROKU_PYTHON_DIR/lib/"
+  mkdir -p "$HEROKU_PYTHON_DIR/lib/pkgconfig"
+  # set the right prefix/lib directories
+  sed -e 's/prefix=\/usr/prefix=\/app\/.heroku\/python/' -e 's/\/x86_64-linux-gnu//' "$HEROKU_PYTHON_DIR/sqlite3/usr/lib/x86_64-linux-gnu/pkgconfig/sqlite3.pc" > "$HEROKU_PYTHON_DIR/lib/pkgconfig/sqlite3.pc"
+  # need to point the libsqlite3.so to the stack image library for /usr/bin/ld -lsqlite3
+  SQLITE3_LIBFILE="/usr/lib/x86_64-linux-gnu/$(readlink -n "$HEROKU_PYTHON_DIR/sqlite3/usr/lib/x86_64-linux-gnu/libsqlite3.so")"
+  ln -s "$SQLITE3_LIBFILE" "$HEROKU_PYTHON_DIR/lib/libsqlite3.so"
+  if [ -z "$HEADERS_ONLY" ]; then
+    mv "$HEROKU_PYTHON_DIR/sqlite3/usr/bin"/* "$HEROKU_PYTHON_DIR/bin/"
+  fi
+
+  # cleanup
+  rm -rf "$HEROKU_PYTHON_DIR/sqlite3/"
+  rm -rf "$HEROKU_PYTHON_DIR/apt/"
+}
+
+buildpack_sqlite3_install() {
+  sqlite3_version
+  HEROKU_PYTHON_DIR="$BUILD_DIR/.heroku/python"
+
+  SQLITE3_VERSION_FILE="$BUILD_DIR/.heroku/python-sqlite3-version"
+  if [ -f "$SQLITE3_VERSION_FILE" ]; then
+    INSTALLED_SQLITE3_VERSION=$(cat "$SQLITE3_VERSION_FILE")
+  fi
+
+  # python version check
+  if python_sqlite3_check "$PYTHON_VERSION"; then
+    # only install if the sqlite3 version has changed
+    if [ "$INSTALLED_SQLITE3_VERSION" != "$SQLITE3_VERSION" ]; then
+      puts-step "Installing SQLite3"
+      sqlite3_install "$BUILD_DIR/.heroku/python" "$SQLITE3_VERSION"
+
+      # save version installed
+      mkdir -p "$CACHE_DIR/.heroku/"
+      echo "$SQLITE3_VERSION" > "$CACHE_DIR/.heroku/python-sqlite3-version"
+    fi
+  fi
+}
@@ -6,8 +6,8 @@ BIN_DIR=$(cd "$(dirname "$0")" || return; pwd) # absolute path
 # shellcheck source=bin/utils
 source "$BIN_DIR/utils"

-DISABLE_COLLECTSTATIC=1 "$(dirname "${0:-}")/compile" "$1" "$2" "$3"
+# Locale support for Pipenv.
+export LC_ALL=C.UTF-8
+export LANG=C.UTF-8

-if [[ -f "$1/requirements-test.txt" ]]; then
-    /app/.heroku/python/bin/pip install -r "$1/requirements-test.txt" --exists-action=w --src=./.heroku/src --disable-pip-version-check --no-cache-dir 2>&1 | cleanup | indent
-fi
+DISABLE_COLLECTSTATIC=1 INSTALL_TEST=1 "$(dirname "${0:-}")/compile" "$1" "$2" "$3"
@@ -58,3 +58,40 @@ measure-size() {
  echo "$(du -s .heroku/python 2>/dev/null || echo 0) | awk '{print $1}')"
 }

+# Python version operator >
+version_gt() {
+  test "$(printf '%s\n' "$@" | sort -V | head -n 1)" != "$1";
+}
+
+# Python verison operator >=
+version_gte() {
+  if [ "$1" == "$2" ]; then
+    return 0
+  fi
+
+  version_gt "$1" "$2"
+}
+
+# Check if Python 2
+python2_check() {
+  VERSION="$1"
+
+  version_gte "$VERSION" "python-2.7.0" && version_gt "python-3.0.0" "$VERSION"
+}
+
+# Check if Python 3
+python3_check() {
+  VERSION="$1"
+
+  version_gte "$VERSION" "python-3.0.0" && version_gt "python-4.0.0" "$VERSION"
+}
+
+# Check if Python version needs to install SQLite3
+python_sqlite3_check() {
+  VERSION="$1"
+  MIN_PYTHON_3="python-3.5.6"
+  MIN_PYTHON_2="python-2.7.15"
+
+  ( python2_check "$VERSION" && version_gte "$VERSION" "$MIN_PYTHON_2" ) \
+    || ( python3_check "$VERSION" && version_gte "$VERSION" "$MIN_PYTHON_3" )
+}
@@ -0,0 +1,13 @@
+[buildpack]
+name = "Python"
+
+  [publish.Ignore]
+  files = [
+    "test/",
+    ".gitignore",
+    ".dockerignore",
+    ".github/",
+    "Dockerfile",
+    "Pipfile",
+    "Pipfile.lock"
+  ]
@@ -3,7 +3,7 @@

 OUT_PREFIX=$1

-echo "Building SQLite..."
+echo "Building SQLite…"


 SOURCE_TARBALL='https://www.sqlite.org/sqlite-autoconf-3070900.tar.gz'
@@ -8,9 +8,9 @@ export PATH="/app/.heroku/python/bin/:$PATH"
 hash -r


-echo "Building gdal..."
+echo "Building gdal…"

-VERSION="1.11.5"
+VERSION="2.2.1"
 SOURCE_TARBALL="http://download.osgeo.org/gdal/${VERSION}/gdal-${VERSION}.tar.gz"

 curl -L $SOURCE_TARBALL | tar zx
@@ -8,16 +8,18 @@ export PATH="/app/.heroku/python/bin/:$PATH"
 hash -r


-echo "Building geos..."
+echo "Building geos…"

-SOURCE_TARBALL='http://download.osgeo.org/geos/geos-3.4.3.tar.bz2'
+VERSION=3.6.2
+
+SOURCE_TARBALL="http://download.osgeo.org/geos/geos-${VERSION}.tar.bz2"

 curl -L $SOURCE_TARBALL | tar xj

-cd geos-3.4.3
+pushd "geos-${VERSION}"
 ./configure --prefix=$OUT_PREFIX --enable-static=no &&
 make
 make install

 # Cleanup
-cd ..
+popd
@@ -13,7 +13,7 @@ export PATH="/app/.heroku/python/bin/:$PATH"
 hash -r


-echo "Building libffi..."
+echo "Building libffi…"

 SOURCE_TARBALL='ftp://sourceware.org/pub/libffi/libffi-3.1.tar.gz'

@@ -20,7 +20,7 @@ dep_archive_name=${dep_dirname}.tar.gz
 dep_url=https://launchpad.net/libmemcached/1.0/${dep_version}/+download/${dep_archive_name}

 # SASL Support.
-echo "-----> Building cyrus-sasl 2.1.26..."
+echo "-----> Building cyrus-sasl 2.1.26…"

 curl -LO ftp://ftp.cyrusimap.org/cyrus-sasl/cyrus-sasl-2.1.26.tar.gz
 # FTP doesn't play well with piping into tar xz
@@ -33,7 +33,7 @@ make -s -j 9
 make install -s
 popd

-echo "-----> Building libmemcached ${dep_version}..."
+echo "-----> Building libmemcached ${dep_version}…"

 curl -L ${dep_url} | tar xz
 pushd ${dep_dirname}
@@ -8,16 +8,17 @@ export PATH="/app/.heroku/python/bin/:$PATH"
 hash -r


-echo "Building gdal..."
+echo "Building gdal…"

-SOURCE_TARBALL='http://download.osgeo.org/proj/proj-4.8.0.tar.gz'
+VERSION=4.9.3
+SOURCE_TARBALL="http://download.osgeo.org/proj/proj-${VERSION}.tar.gz"

 curl -L $SOURCE_TARBALL | tar zx

-cd proj-4.8.0
-./configure --prefix=$OUT_PREFIX --enable-static=no &&
+pushd "proj-${VERSION}"
+./configure --prefix=$OUT_PREFIX --enable-static=no
 make
 make install

 # Cleanup
-cd ..
+popd
@@ -6,7 +6,7 @@

 OUT_PREFIX=$1

-echo "Building PyPy..."
+echo "Building PyPy…"
 SOURCE_TARBALL='https://bitbucket.org/pypy/pypy/downloads/pypy2-v5.3.1-linux64.tar.bz2'
 curl -L $SOURCE_TARBALL | tar jx
 cp -R pypy2-v5.3.1-linux64/* $OUT_PREFIX
@@ -6,7 +6,7 @@

 OUT_PREFIX=$1

-echo "Building PyPy..."
+echo "Building PyPy…"
 SOURCE_TARBALL='https://bitbucket.org/pypy/pypy/downloads/pypy2-v5.6.0-linux64.tar.bz2'
 curl -L $SOURCE_TARBALL | tar jx
 cp -R pypy2-v5.6.0-linux64/* $OUT_PREFIX
@@ -6,7 +6,7 @@

 OUT_PREFIX=$1

-echo "Building PyPy..."
+echo "Building PyPy…"
 SOURCE_TARBALL='https://bitbucket.org/pypy/pypy/downloads/pypy2-v5.7.0-linux64.tar.bz2'
 curl -L $SOURCE_TARBALL | tar jx
 cp -R pypy2-v5.7.0-linux64/* $OUT_PREFIX
@@ -6,7 +6,7 @@

 OUT_PREFIX=$1

-echo "Building PyPy..."
+echo "Building PyPy…"
 SOURCE_TARBALL='https://bitbucket.org/pypy/pypy/downloads/pypy2-v5.7.1-linux64.tar.bz2'
 curl -L $SOURCE_TARBALL | tar jx
 cp -R pypy2-v5.7.1-linux64/* $OUT_PREFIX
@@ -4,7 +4,7 @@

 OUT_PREFIX=$1

-echo "Building PyPy..."
+echo "Building PyPy…"
 SOURCE_TARBALL='https://bitbucket.org/pypy/pypy/downloads/pypy2-v5.8.0-linux64.tar.bz2'
 curl -L $SOURCE_TARBALL | tar jx
 cp -R pypy2-v5.8.0-linux64/* $OUT_PREFIX
@@ -6,7 +6,7 @@

 OUT_PREFIX=$1

-echo "Building PyPy..."
+echo "Building PyPy…"
 SOURCE_TARBALL='https://bitbucket.org/pypy/pypy/downloads/pypy3-2.4.0-linux64.tar.bz2'
 curl -L $SOURCE_TARBALL | tar jx
 cp -R pypy3-2.4.0-linux64/* $OUT_PREFIX
@@ -6,7 +6,7 @@

 OUT_PREFIX=$1

-echo "Building PyPy..."
+echo "Building PyPy…"
 SOURCE_TARBALL='https://bitbucket.org/pypy/pypy/downloads/pypy3.3-v5.5.0-alpha-linux64.tar.bz2'
 curl -L $SOURCE_TARBALL | tar jx
 cp -R pypy3-v5.5.0-linux64/* $OUT_PREFIX
@@ -4,7 +4,7 @@

 OUT_PREFIX=$1

-echo "Building PyPy..."
+echo "Building PyPy…"
 SOURCE_TARBALL='https://bitbucket.org/pypy/pypy/downloads/pypy3-v5.7.1-linux64.tar.bz2'
 curl -L $SOURCE_TARBALL | tar jx
 cp -R pypy3-v5.7.1-linux64/* $OUT_PREFIX
@@ -4,7 +4,7 @@

 OUT_PREFIX=$1

-echo "Building PyPy..."
+echo "Building PyPy…"
 SOURCE_TARBALL='https://bitbucket.org/pypy/pypy/downloads/pypy3-v5.8.0-linux64.tar.bz2'
 curl -L $SOURCE_TARBALL | tar jx
 cp -R pypy3-v5.8.0-linux64/* $OUT_PREFIX
@@ -4,7 +4,7 @@

 OUT_PREFIX=$1

-echo "Building Python..."
+echo "Building Python…"
 SOURCE_TARBALL='https://python.org/ftp/python/2.7.10/Python-2.7.10.tgz'
 curl -L $SOURCE_TARBALL | tar xz
 mv Python-2.7.10 src
@@ -4,7 +4,7 @@

 OUT_PREFIX=$1

-echo "Building Python..."
+echo "Building Python…"
 SOURCE_TARBALL='https://python.org/ftp/python/2.7.11/Python-2.7.11.tgz'
 curl -L $SOURCE_TARBALL | tar xz
 mv Python-2.7.11 src
@@ -4,7 +4,7 @@

 OUT_PREFIX=$1

-echo "Building Python..."
+echo "Building Python…"
 SOURCE_TARBALL='https://python.org/ftp/python/2.7.12/Python-2.7.12.tgz'
 curl -L $SOURCE_TARBALL | tar xz
 mv Python-2.7.12 src
@@ -4,7 +4,7 @@

 OUT_PREFIX=$1

-echo "Building Python..."
+echo "Building Python…"
 SOURCE_TARBALL='https://python.org/ftp/python/2.7.13/Python-2.7.13.tgz'
 curl -L $SOURCE_TARBALL | tar xz
 mv Python-2.7.13 src
@@ -0,0 +1,19 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+# Build Deps: libraries/sqlite
+
+OUT_PREFIX=$1
+
+echo "Building Python…"
+SOURCE_TARBALL='https://python.org/ftp/python/2.7.14/Python-2.7.14.tgz'
+curl -L $SOURCE_TARBALL | tar xz
+mv Python-2.7.14 src
+cd src
+
+./configure --prefix=$OUT_PREFIX  --enable-unicode=ucs4 --with-ensurepip=no
+make
+make install
+
+# Remove unneeded test directories, similar to the official Docker Python images:
+# https://github.com/docker-library/python
+find "${OUT_PREFIX}" \( -type d -a \( -name test -o -name tests \) \) -exec rm -rf '{}' +
@@ -0,0 +1,27 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+
+OUT_PREFIX=$1
+BIN_DIR="$(cd "$(dirname "$0")"/../.. || exit; pwd)/bin"
+export BIN_DIR
+
+# shellcheck source=bin/utils
+source "$BIN_DIR/steps/sqlite3"
+
+sqlite3_version
+echo "Setting up SQLite3 Headers for $SQLITE3_VERSION"
+sqlite3_install "$OUT_PREFIX" "$SQLITE3_VERSION" 1
+
+echo "Building Python…"
+SOURCE_TARBALL='https://python.org/ftp/python/2.7.15/Python-2.7.15.tgz'
+curl -L $SOURCE_TARBALL | tar xz
+mv Python-2.7.15 src
+cd src
+
+./configure --prefix=$OUT_PREFIX  --enable-unicode=ucs4 --with-ensurepip=no
+make
+make install
+
+# Remove unneeded test directories, similar to the official Docker Python images:
+# https://github.com/docker-library/python
+find "${OUT_PREFIX}" \( -type d -a \( -name test -o -name tests \) \) -exec rm -rf '{}' +
@@ -0,0 +1,27 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+
+OUT_PREFIX=$1
+BIN_DIR="$(cd "$(dirname "$0")"/../.. || exit; pwd)/bin"
+export BIN_DIR
+
+# shellcheck source=bin/utils
+source "$BIN_DIR/steps/sqlite3"
+
+sqlite3_version
+echo "Setting up SQLite3 Headers for $SQLITE3_VERSION"
+sqlite3_install "$OUT_PREFIX" "$SQLITE3_VERSION" 1
+
+echo "Building Python…"
+SOURCE_TARBALL='https://python.org/ftp/python/2.7.16/Python-2.7.16.tgz'
+curl -L $SOURCE_TARBALL | tar xz
+mv Python-2.7.16 src
+cd src
+
+./configure --prefix=$OUT_PREFIX  --enable-unicode=ucs4 --with-ensurepip=no
+make
+make install
+
+# Remove unneeded test directories, similar to the official Docker Python images:
+# https://github.com/docker-library/python
+find "${OUT_PREFIX}" \( -type d -a \( -name test -o -name tests \) \) -exec rm -rf '{}' +
@@ -4,7 +4,7 @@

 OUT_PREFIX=$1

-echo "Building Python..."
+echo "Building Python…"
 SOURCE_TARBALL='https://python.org/ftp/python/2.7.9/Python-2.7.9.tgz'
 curl -L $SOURCE_TARBALL | tar xz
 mv Python-2.7.9 src
@@ -0,0 +1,32 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+
+OUT_PREFIX=$1
+BIN_DIR="$(cd "$(dirname "$0")"/../.. || exit; pwd)/bin"
+export BIN_DIR
+
+# shellcheck source=bin/utils
+source "$BIN_DIR/steps/sqlite3"
+
+sqlite3_version
+echo "Setting up SQLite3 Headers for $SQLITE3_VERSION"
+sqlite3_install "$OUT_PREFIX" "$SQLITE3_VERSION" 1
+
+echo "Building Python…"
+SOURCE_TARBALL='https://python.org/ftp/python/3.7.2/Python-3.7.2.tgz'
+curl -L $SOURCE_TARBALL | tar xz
+mv Python-3.7.2 src
+cd src
+
+./configure --prefix=$OUT_PREFIX --with-ensurepip=no
+make
+make install
+
+# Remove unneeded test directories, similar to the official Docker Python images:
+# https://github.com/docker-library/python
+find "${OUT_PREFIX}" \( -type d -a \( -name test -o -name tests \) \) -exec rm -rf '{}' +
+
+# Remove spare /
+LOCATION=${OUT_PREFIX%?}
+
+ln $LOCATION/bin/python3 $LOCATION/bin/python
@@ -0,0 +1,32 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+
+OUT_PREFIX=$1
+BIN_DIR="$(cd "$(dirname "$0")"/../.. || exit; pwd)/bin"
+export BIN_DIR
+
+# shellcheck source=bin/utils
+source "$BIN_DIR/steps/sqlite3"
+
+sqlite3_version
+echo "Setting up SQLite3 Headers for $SQLITE3_VERSION"
+sqlite3_install "$OUT_PREFIX" "$SQLITE3_VERSION" 1
+
+echo "Building Python…"
+SOURCE_TARBALL='https://python.org/ftp/python/3.4.9/Python-3.4.9.tgz'
+curl -L $SOURCE_TARBALL | tar xz
+mv Python-3.4.9 src
+cd src
+
+./configure --prefix=$OUT_PREFIX --with-ensurepip=no
+make
+make install
+
+# Remove unneeded test directories, similar to the official Docker Python images:
+# https://github.com/docker-library/python
+find "${OUT_PREFIX}" \( -type d -a \( -name test -o -name tests \) \) -exec rm -rf '{}' +
+
+# Remove spare /
+LOCATION=${OUT_PREFIX%?}
+
+ln $LOCATION/bin/python3 $LOCATION/bin/python
@@ -4,7 +4,7 @@

 OUT_PREFIX=$1

-echo "Building Python..."
+echo "Building Python…"
 SOURCE_TARBALL='https://python.org/ftp/python/3.5.2/Python-3.5.2.tgz'
 curl -L $SOURCE_TARBALL | tar xz
 mv Python-3.5.2 src
@@ -4,7 +4,7 @@

 OUT_PREFIX=$1

-echo "Building Python..."
+echo "Building Python…"
 SOURCE_TARBALL='https://python.org/ftp/python/3.5.3/Python-3.5.3.tgz'
 curl -L $SOURCE_TARBALL | tar xz
 mv Python-3.5.3 src
@@ -0,0 +1,32 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+
+OUT_PREFIX=$1
+BIN_DIR="$(cd "$(dirname "$0")"/../.. || exit; pwd)/bin"
+export BIN_DIR
+
+# shellcheck source=bin/utils
+source "$BIN_DIR/steps/sqlite3"
+
+sqlite3_version
+echo "Setting up SQLite3 Headers for $SQLITE3_VERSION"
+sqlite3_install "$OUT_PREFIX" "$SQLITE3_VERSION" 1
+
+echo "Building Python…"
+SOURCE_TARBALL='https://python.org/ftp/python/3.5.6/Python-3.5.6.tgz'
+curl -L $SOURCE_TARBALL | tar xz
+mv Python-3.5.6 src
+cd src
+
+./configure --prefix=$OUT_PREFIX --with-ensurepip=no
+make
+make install
+
+# Remove unneeded test directories, similar to the official Docker Python images:
+# https://github.com/docker-library/python
+find "${OUT_PREFIX}" \( -type d -a \( -name test -o -name tests \) \) -exec rm -rf '{}' +
+
+# Remove spare /
+LOCATION=${OUT_PREFIX%?}
+
+ln $LOCATION/bin/python3 $LOCATION/bin/python
@@ -0,0 +1,32 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+
+OUT_PREFIX=$1
+BIN_DIR="$(cd "$(dirname "$0")"/../.. || exit; pwd)/bin"
+export BIN_DIR
+
+# shellcheck source=bin/utils
+source "$BIN_DIR/steps/sqlite3"
+
+sqlite3_version
+echo "Setting up SQLite3 Headers for $SQLITE3_VERSION"
+sqlite3_install "$OUT_PREFIX" "$SQLITE3_VERSION" 1
+
+echo "Building Python…"
+SOURCE_TARBALL='https://python.org/ftp/python/3.5.7/Python-3.5.7.tgz'
+curl -L $SOURCE_TARBALL | tar xz
+mv Python-3.5.7 src
+cd src
+
+./configure --prefix=$OUT_PREFIX --with-ensurepip=no
+make
+make install
+
+# Remove unneeded test directories, similar to the official Docker Python images:
+# https://github.com/docker-library/python
+find "${OUT_PREFIX}" \( -type d -a \( -name test -o -name tests \) \) -exec rm -rf '{}' +
+
+# Remove spare /
+LOCATION=${OUT_PREFIX%?}
+
+ln $LOCATION/bin/python3 $LOCATION/bin/python
@@ -4,7 +4,7 @@

 OUT_PREFIX=$1

-echo "Building Python..."
+echo "Building Python…"
 SOURCE_TARBALL='https://python.org/ftp/python/3.6.0/Python-3.6.0.tgz'
 curl -L $SOURCE_TARBALL | tar xz
 mv Python-3.6.0 src
@@ -4,7 +4,7 @@

 OUT_PREFIX=$1

-echo "Building Python..."
+echo "Building Python…"
 SOURCE_TARBALL='https://python.org/ftp/python/3.6.1/Python-3.6.1.tgz'
 curl -L $SOURCE_TARBALL | tar xz
 mv Python-3.6.1 src
@@ -4,7 +4,7 @@

 OUT_PREFIX=$1

-echo "Building Python..."
+echo "Building Python…"
 SOURCE_TARBALL='https://python.org/ftp/python/3.6.2/Python-3.6.2.tgz'
 curl -L $SOURCE_TARBALL | tar xz
 mv Python-3.6.2 src
@@ -0,0 +1,21 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+# Build Deps: libraries/sqlite
+
+OUT_PREFIX=$1
+
+echo "Building Python…"
+SOURCE_TARBALL='https://python.org/ftp/python/3.6.3/Python-3.6.3.tgz'
+curl -L $SOURCE_TARBALL | tar xz
+mv Python-3.6.3 src
+cd src
+
+./configure --prefix=$OUT_PREFIX --with-ensurepip=no
+make
+make install
+
+# Remove unneeded test directories, similar to the official Docker Python images:
+# https://github.com/docker-library/python
+find "${OUT_PREFIX}" \( -type d -a \( -name test -o -name tests \) \) -exec rm -rf '{}' +
+
+ln $OUT_PREFIX/bin/python3 $OUT_PREFIX/bin/python
@@ -0,0 +1,21 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+# Build Deps: libraries/sqlite
+
+OUT_PREFIX=$1
+
+echo "Building Python…"
+SOURCE_TARBALL='https://python.org/ftp/python/3.6.4/Python-3.6.4.tgz'
+curl -L $SOURCE_TARBALL | tar xz
+mv Python-3.6.4 src
+cd src
+
+./configure --prefix=$OUT_PREFIX --with-ensurepip=no
+make
+make install
+
+# Remove unneeded test directories, similar to the official Docker Python images:
+# https://github.com/docker-library/python
+find "${OUT_PREFIX}" \( -type d -a \( -name test -o -name tests \) \) -exec rm -rf '{}' +
+
+ln $OUT_PREFIX/bin/python3 $OUT_PREFIX/bin/python
@@ -0,0 +1,21 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+# Build Deps: libraries/sqlite
+
+OUT_PREFIX=$1
+
+echo "Building Python…"
+SOURCE_TARBALL='https://python.org/ftp/python/3.6.5/Python-3.6.5.tgz'
+curl -L $SOURCE_TARBALL | tar xz
+mv Python-3.6.5 src
+cd src
+
+./configure --prefix=$OUT_PREFIX --with-ensurepip=no
+make
+make install
+
+# Remove unneeded test directories, similar to the official Docker Python images:
+# https://github.com/docker-library/python
+find "${OUT_PREFIX}" \( -type d -a \( -name test -o -name tests \) \) -exec rm -rf '{}' +
+
+ln $OUT_PREFIX/bin/python3 $OUT_PREFIX/bin/python
@@ -0,0 +1,29 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+
+OUT_PREFIX=$1
+BIN_DIR="$(cd "$(dirname "$0")"/../.. || exit; pwd)/bin"
+export BIN_DIR
+
+# shellcheck source=bin/utils
+source "$BIN_DIR/steps/sqlite3"
+
+sqlite3_version
+echo "Setting up SQLite3 Headers for $SQLITE3_VERSION"
+sqlite3_install "$OUT_PREFIX" "$SQLITE3_VERSION" 1
+
+echo "Building Python…"
+SOURCE_TARBALL='https://python.org/ftp/python/3.6.6/Python-3.6.6.tgz'
+curl -L $SOURCE_TARBALL | tar xz
+mv Python-3.6.6 src
+cd src
+
+./configure --prefix=$OUT_PREFIX --with-ensurepip=no
+make
+make install
+
+# Remove unneeded test directories, similar to the official Docker Python images:
+# https://github.com/docker-library/python
+find "${OUT_PREFIX}" \( -type d -a \( -name test -o -name tests \) \) -exec rm -rf '{}' +
+
+ln $OUT_PREFIX/bin/python3 $OUT_PREFIX/bin/python
@@ -0,0 +1,32 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+
+OUT_PREFIX=$1
+BIN_DIR="$(cd "$(dirname "$0")"/../.. || exit; pwd)/bin"
+export BIN_DIR
+
+# shellcheck source=bin/utils
+source "$BIN_DIR/steps/sqlite3"
+
+sqlite3_version
+echo "Setting up SQLite3 Headers for $SQLITE3_VERSION"
+sqlite3_install "$OUT_PREFIX" "$SQLITE3_VERSION" 1
+
+echo "Building Python…"
+SOURCE_TARBALL='https://python.org/ftp/python/3.6.7/Python-3.6.7.tgz'
+curl -L $SOURCE_TARBALL | tar xz
+mv Python-3.6.7 src
+cd src
+
+./configure --prefix=$OUT_PREFIX --with-ensurepip=no
+make
+make install
+
+# Remove unneeded test directories, similar to the official Docker Python images:
+# https://github.com/docker-library/python
+find "${OUT_PREFIX}" \( -type d -a \( -name test -o -name tests \) \) -exec rm -rf '{}' +
+
+# Remove spare /
+LOCATION=${OUT_PREFIX%?}
+
+ln $LOCATION/bin/python3 $LOCATION/bin/python
@@ -0,0 +1,32 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+
+OUT_PREFIX=$1
+BIN_DIR="$(cd "$(dirname "$0")"/../.. || exit; pwd)/bin"
+export BIN_DIR
+
+# shellcheck source=bin/utils
+source "$BIN_DIR/steps/sqlite3"
+
+sqlite3_version
+echo "Setting up SQLite3 Headers for $SQLITE3_VERSION"
+sqlite3_install "$OUT_PREFIX" "$SQLITE3_VERSION" 1
+
+echo "Building Python…"
+SOURCE_TARBALL='https://python.org/ftp/python/3.6.8/Python-3.6.8.tgz'
+curl -L $SOURCE_TARBALL | tar xz
+mv Python-3.6.8 src
+cd src
+
+./configure --prefix=$OUT_PREFIX --with-ensurepip=no
+make
+make install
+
+# Remove unneeded test directories, similar to the official Docker Python images:
+# https://github.com/docker-library/python
+find "${OUT_PREFIX}" \( -type d -a \( -name test -o -name tests \) \) -exec rm -rf '{}' +
+
+# Remove spare /
+LOCATION=${OUT_PREFIX%?}
+
+ln $LOCATION/bin/python3 $LOCATION/bin/python
@@ -0,0 +1,29 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+
+OUT_PREFIX=$1
+BIN_DIR="$(cd "$(dirname "$0")"/../.. || exit; pwd)/bin"
+export BIN_DIR
+
+# shellcheck source=bin/utils
+source "$BIN_DIR/steps/sqlite3"
+
+sqlite3_version
+echo "Setting up SQLite3 Headers for $SQLITE3_VERSION"
+sqlite3_install "$OUT_PREFIX" "$SQLITE3_VERSION" 1
+
+echo "Building Python…"
+SOURCE_TARBALL='https://python.org/ftp/python/3.7.0/Python-3.7.0.tgz'
+curl -L $SOURCE_TARBALL | tar xz
+mv Python-3.7.0 src
+cd src
+
+./configure --prefix=$OUT_PREFIX --with-ensurepip=no
+make
+make install
+
+# Remove unneeded test directories, similar to the official Docker Python images:
+# https://github.com/docker-library/python
+find "${OUT_PREFIX}" \( -type d -a \( -name test -o -name tests \) \) -exec rm -rf '{}' +
+
+ln $OUT_PREFIX/bin/python3 $OUT_PREFIX/bin/python
@@ -0,0 +1,32 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+
+OUT_PREFIX=$1
+BIN_DIR="$(cd "$(dirname "$0")"/../.. || exit; pwd)/bin"
+export BIN_DIR
+
+# shellcheck source=bin/utils
+source "$BIN_DIR/steps/sqlite3"
+
+sqlite3_version
+echo "Setting up SQLite3 Headers for $SQLITE3_VERSION"
+sqlite3_install "$OUT_PREFIX" "$SQLITE3_VERSION" 1
+
+echo "Building Python…"
+SOURCE_TARBALL='https://python.org/ftp/python/3.7.1/Python-3.7.1.tgz'
+curl -L $SOURCE_TARBALL | tar xz
+mv Python-3.7.1 src
+cd src
+
+./configure --prefix=$OUT_PREFIX --with-ensurepip=no
+make
+make install
+
+# Remove unneeded test directories, similar to the official Docker Python images:
+# https://github.com/docker-library/python
+find "${OUT_PREFIX}" \( -type d -a \( -name test -o -name tests \) \) -exec rm -rf '{}' +
+
+# Remove spare /
+LOCATION=${OUT_PREFIX%?}
+
+ln $LOCATION/bin/python3 $LOCATION/bin/python
@@ -0,0 +1,32 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+
+OUT_PREFIX=$1
+BIN_DIR="$(cd "$(dirname "$0")"/../.. || exit; pwd)/bin"
+export BIN_DIR
+
+# shellcheck source=bin/utils
+source "$BIN_DIR/steps/sqlite3"
+
+sqlite3_version
+echo "Setting up SQLite3 Headers for $SQLITE3_VERSION"
+sqlite3_install "$OUT_PREFIX" "$SQLITE3_VERSION" 1
+
+echo "Building Python…"
+SOURCE_TARBALL='https://python.org/ftp/python/3.7.2/Python-3.7.2.tgz'
+curl -L $SOURCE_TARBALL | tar xz
+mv Python-3.7.2 src
+cd src
+
+./configure --prefix=$OUT_PREFIX --with-ensurepip=no
+make
+make install
+
+# Remove unneeded test directories, similar to the official Docker Python images:
+# https://github.com/docker-library/python
+find "${OUT_PREFIX}" \( -type d -a \( -name test -o -name tests \) \) -exec rm -rf '{}' +
+
+# Remove spare /
+LOCATION=${OUT_PREFIX%?}
+
+ln $LOCATION/bin/python3 $LOCATION/bin/python
@@ -0,0 +1,32 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+
+OUT_PREFIX=$1
+BIN_DIR="$(cd "$(dirname "$0")"/../.. || exit; pwd)/bin"
+export BIN_DIR
+
+# shellcheck source=bin/utils
+source "$BIN_DIR/steps/sqlite3"
+
+sqlite3_version
+echo "Setting up SQLite3 Headers for $SQLITE3_VERSION"
+sqlite3_install "$OUT_PREFIX" "$SQLITE3_VERSION" 1
+
+echo "Building Python…"
+SOURCE_TARBALL='https://python.org/ftp/python/3.7.3/Python-3.7.3.tgz'
+curl -L $SOURCE_TARBALL | tar xz
+mv Python-3.7.3 src
+cd src
+
+./configure --prefix=$OUT_PREFIX --with-ensurepip=no
+make
+make install
+
+# Remove unneeded test directories, similar to the official Docker Python images:
+# https://github.com/docker-library/python
+find "${OUT_PREFIX}" \( -type d -a \( -name test -o -name tests \) \) -exec rm -rf '{}' +
+
+# Remove spare /
+LOCATION=${OUT_PREFIX%?}
+
+ln $LOCATION/bin/python3 $LOCATION/bin/python
@@ -0,0 +1,5 @@
+#!/usr/bin/env bash
+
+sudo apt-get -qq update
+sudo apt-get install software-properties-common
+curl --fail --retry 3 --retry-delay 1 --connect-timeout 3 --max-time 30 https://cli-assets.heroku.com/install-ubuntu.sh | sh
@@ -0,0 +1,38 @@
+#!/bin/bash
+
+set -e
+
+BP_NAME=${1:-"heroku/python"}
+
+curVersion=$(heroku buildpacks:versions "$BP_NAME" | awk 'FNR == 3 { print $1 }')
+newVersion="v$((curVersion + 1))"
+
+read -p "Deploy as version: $newVersion [y/n]? " choice
+case "$choice" in
+  y|Y ) echo "";;
+  n|N ) exit 0;;
+  * ) exit 1;;
+esac
+
+originMaster=$(git rev-parse origin/master)
+echo "Tagging commit $originMaster with $newVersion... "
+git tag "$newVersion" "${originMaster:?}"
+git push origin refs/tags/$newVersion
+
+heroku buildpacks:publish "$BP_NAME" "$newVersion"
+
+if [ $(git tag | grep -q previous-version) ]; then
+    echo "Updating previous-version tag"
+    git tag -d previous-version
+    git push origin :previous-version
+    git tag previous-version latest-version
+fi
+if [ $(git tag | grep -q latest-version) ]; then
+    echo "Updating latest-version tag"
+    git tag -d latest-version
+    git push origin :latest-version
+    git tag latest-version "${originMaster:?}"
+    git push --tags
+fi
+
+echo "Done."
@@ -0,0 +1,5 @@
+{
+  "python": [
+    "heroku/python-getting-started"
+  ]
+}
@@ -0,0 +1,3 @@
+---
+- - "./repos/python/python-getting-started"
+  - f56b90499ec11e1c9576da2f8c7331300e189db3
@@ -1 +1,3 @@
-bob-builder==0.0.13
+docopt==0.6.2
+bob-builder
+boto==2.48.0
@@ -0,0 +1,10 @@
+require_relative '../spec_helper'
+
+describe "Python!!!!!!!!!!!" do
+  it "🐍" do
+    Hatchet::Runner.new('python-getting-started', stack: DEFAULT_STACK).deploy do |app|
+      expect(app.output).to           match(/Installing pip/)
+      expect(app.run('python -V')).to match(/3.6.8/)
+    end
+  end
+end
@@ -0,0 +1,23 @@
+ENV['HATCHET_BUILDPACK_BASE'] = 'https://github.com/' + ENV['TRAVIS_REPO_SLUG'] + '.git'
+
+require 'rspec/core'
+require 'rspec/retry'
+require 'hatchet'
+
+require 'date'
+
+RSpec.configure do |config|
+  config.full_backtrace      = true
+  config.verbose_retry       = true # show retry status in spec process
+  config.default_retry_count = 2 if ENV['IS_RUNNING_ON_CI'] # retry all tests that fail again
+  config.expect_with :rspec do |c|
+    c.syntax = :expect
+  end
+end
+
+if ENV['TRAVIS']
+  # Don't execute tests against "merge" commits
+  exit 0 if ENV['TRAVIS_PULL_REQUEST'] != 'false' && ENV['TRAVIS_BRANCH'] == 'master'
+end
+
+DEFAULT_STACK = 'heroku-16'
@@ -0,0 +1 @@
+apache-airflow==1.10.2
@@ -0,0 +1 @@
+cffi
@@ -0,0 +1,5 @@
+venv
+*.pyc
+staticfiles
+.env
+db.sqlite3
@@ -0,0 +1,16 @@
+[[source]]
+
+url = "https://pypi.python.org/simple"
+verify_ssl = true
+
+
+[packages]
+
+django = "*"
+gunicorn = "*"
+django-heroku = "*"
+
+
+[requires]
+
+python_version = "3.6"
@@ -0,0 +1,118 @@
+{
+    "_meta": {
+        "hash": {
+            "sha256": "7843aa61794626156c5dbfa26d6be61df24889c396f04a8dead353d23e2899d6"
+        },
+        "host-environment-markers": {
+            "implementation_name": "cpython",
+            "implementation_version": "3.6.3",
+            "os_name": "posix",
+            "platform_machine": "x86_64",
+            "platform_python_implementation": "CPython",
+            "platform_release": "17.3.0",
+            "platform_system": "Darwin",
+            "platform_version": "Darwin Kernel Version 17.3.0: Thu Nov  9 18:09:22 PST 2017; root:xnu-4570.31.3~1/RELEASE_X86_64",
+            "python_full_version": "3.6.3",
+            "python_version": "3.6",
+            "sys_platform": "darwin"
+        },
+        "pipfile-spec": 6,
+        "requires": {
+            "python_version": "3.6"
+        },
+        "sources": [
+            {
+                "url": "https://pypi.python.org/simple",
+                "verify_ssl": true
+            }
+        ]
+    },
+    "default": {
+        "dj-database-url": {
+            "hashes": [
+                "sha256:e16d94c382ea0564c48038fa7fe8d9c890ef1ab1a8ec4cb48e732c124b9482fd",
+                "sha256:a6832d8445ee9d788c5baa48aef8130bf61fdc442f7d9a548424d25cd85c9f08"
+            ],
+            "version": "==0.4.2"
+        },
+        "django": {
+            "hashes": [
+                "sha256:af18618ce3291be5092893d8522fe3919661bf3a1fb60e3858ae74865a4f07c2",
+                "sha256:9614851d4a7ff8cbd32b73c6076441f377c45a5bbff7e771798fb02c43c31f47"
+            ],
+            "version": "==2.0"
+        },
+        "django-heroku": {
+            "hashes": [
+                "sha256:193bacbe644a607642f6b60acd0a382d6abf4a1f7578f8d3eb10659457efe904",
+                "sha256:af6c723872553b7427121a865eb9fce70d566b9ad26d7defcdcd03a8acea56c8"
+            ],
+            "version": "==0.1.0"
+        },
+        "gunicorn": {
+            "hashes": [
+                "sha256:75af03c99389535f218cc596c7de74df4763803f7b63eb09d77e92b3956b36c6",
+                "sha256:eee1169f0ca667be05db3351a0960765620dad53f53434262ff8901b68a1b622"
+            ],
+            "version": "==19.7.1"
+        },
+        "psycopg2": {
+            "hashes": [
+                "sha256:594aa9a095de16614f703d759e10c018bdffeafce2921b8e80a0e8a0ebbc12e5",
+                "sha256:1cf5d84290c771eeecb734abe2c6c3120e9837eb12f99474141a862b9061ac51",
+                "sha256:0344b181e1aea37a58c218ccb0f0f771295de9aa25a625ed076e6996c6530f9e",
+                "sha256:25250867a4cd1510fb755ef9cb38da3065def999d8e92c44e49a39b9b76bc893",
+                "sha256:317612d5d0ca4a9f7e42afb2add69b10be360784d21ce4ecfbca19f1f5eadf43",
+                "sha256:9d6266348b15b4a48623bf4d3e50445d8e581da413644f365805b321703d0fac",
+                "sha256:ddca39cc55877653b5fcf59976d073e3d58c7c406ef54ae8e61ddf8782867182",
+                "sha256:988d2ec7560d42ef0ac34b3b97aad14c4f068792f00e1524fa1d3749fe4e4b64",
+                "sha256:7a9c6c62e6e05df5406e9b5235c31c376a22620ef26715a663cee57083b3c2ea",
+                "sha256:7a75565181e75ba0b9fb174b58172bf6ea9b4331631cfe7bafff03f3641f5d73",
+                "sha256:94e4128ba1ea56f02522fffac65520091a9de3f5c00da31539e085e13db4771b",
+                "sha256:92179bd68c2efe72924a99b6745a9172471931fc296f9bfdf9645b75eebd6344",
+                "sha256:b9358e203168fef7bfe9f430afaed3a2a624717a1d19c7afa7dfcbd76e3cd95c",
+                "sha256:009e0bc09a57dbef4b601cb8b46a2abad51f5274c8be4bba276ff2884cd4cc53",
+                "sha256:d3ac07240e2304181ffdb13c099840b5eb555efc7be9344503c0c03aa681de79",
+                "sha256:40fa5630cd7d237cd93c4d4b64b9e5ed9273d1cfce55241c7f9066f5db70629d",
+                "sha256:6c2f1a76a9ebd9ecf7825b9e20860139ca502c2bf1beabf6accf6c9e66a7e0c3",
+                "sha256:37f54452c7787dbdc0a634ca9773362b91709917f0b365ed14b831f03cbd34ba",
+                "sha256:8f5942a4daf1ffac42109dc4a72f786af4baa4fa702ede1d7c57b4b696c2e7d6",
+                "sha256:bf708455cd1e9fa96c05126e89a0c59b200d086c7df7bbafc7d9be769e4149a3",
+                "sha256:82c40ea3ac1555e0462803380609fbe8b26f52620f3d4f8eb480cfd8ceed8a14",
+                "sha256:207ba4f9125a0a4200691e82d5eee7ea1485708eabe99a07fc7f08696fae62f4",
+                "sha256:0cd4c848f0e9d805d531e44973c8f48962e20eb7fc0edac3db4f9dbf9ed5ab82",
+                "sha256:57baf63aeb2965ca4b52613ce78e968b6d2bde700c97f6a7e8c6c236b51ab83e",
+                "sha256:2954557393cfc9a5c11a5199c7a78cd9c0c793a047552d27b1636da50d013916",
+                "sha256:7c31dade89634807196a6b20ced831fbd5bec8a21c4e458ea950c9102c3aa96f",
+                "sha256:1286dd16d0e46d59fa54582725986704a7a3f3d9aca6c5902a7eceb10c60cb7e",
+                "sha256:697ff63bc5451e0b0db48ad205151123d25683b3754198be7ab5fcb44334e519",
+                "sha256:fc993c9331d91766d54757bbc70231e29d5ceb2d1ac08b1570feaa0c38ab9582",
+                "sha256:9d64fed2681552ed642e9c0cc831a9e95ab91de72b47d0cb68b5bf506ba88647",
+                "sha256:5c3213be557d0468f9df8fe2487eaf2990d9799202c5ff5cb8d394d09fad9b2a"
+            ],
+            "version": "==2.7.3.2"
+        },
+        "pytz": {
+            "hashes": [
+                "sha256:80af0f3008046b9975242012a985f04c5df1f01eed4ec1633d56cc47a75a6a48",
+                "sha256:feb2365914948b8620347784b6b6da356f31c9d03560259070b2f30cff3d469d",
+                "sha256:59707844a9825589878236ff2f4e0dc9958511b7ffaae94dc615da07d4a68d33",
+                "sha256:d0ef5ef55ed3d37854320d4926b04a4cb42a2e88f71da9ddfdacfde8e364f027",
+                "sha256:c41c62827ce9cafacd6f2f7018e4f83a6f1986e87bfd000b8cfbd4ab5da95f1a",
+                "sha256:8cc90340159b5d7ced6f2ba77694d946fc975b09f1a51d93f3ce3bb399396f94",
+                "sha256:dd2e4ca6ce3785c8dd342d1853dd9052b19290d5bf66060846e5dc6b8d6667f7",
+                "sha256:699d18a2a56f19ee5698ab1123bbcc1d269d061996aeb1eda6d89248d3542b82",
+                "sha256:fae4cffc040921b8a2d60c6cf0b5d662c1190fe54d718271db4eb17d44a185b7"
+            ],
+            "version": "==2017.3"
+        },
+        "whitenoise": {
+            "hashes": [
+                "sha256:15f43b2e701821b95c9016cf469d29e2a546cb1c7dead584ba82c36f843995cf",
+                "sha256:9d81515f2b5b27051910996e1e860b1332e354d9e7bcf30c98f21dcb6713e0dd"
+            ],
+            "version": "==3.3.1"
+        }
+    },
+    "develop": {}
+}
@@ -0,0 +1 @@
+web: gunicorn gettingstarted.wsgi
@@ -0,0 +1 @@
+web: python manage.py runserver 0.0.0.0:5000
@@ -0,0 +1,44 @@
+# Python: Getting Started
+
+A barebones Django app, which can easily be deployed to Heroku.
+
+This application supports the [Getting Started with Python on Heroku](https://devcenter.heroku.com/articles/getting-started-with-python) article - check it out.
+
+## Running Locally
+
+Make sure you have Python [installed properly](http://install.python-guide.org). Also, install the [Heroku CLI](https://devcenter.heroku.com/articles/heroku-cli) and [Postgres](https://devcenter.heroku.com/articles/heroku-postgresql#local-setup).
+
+```sh
+$ git clone git@github.com:heroku/python-getting-started.git
+$ cd python-getting-started
+
+$ pipenv install
+
+$ createdb python_getting_started
+
+$ python manage.py migrate
+$ python manage.py collectstatic
+
+$ heroku local
+```
+
+Your app should now be running on [localhost:5000](http://localhost:5000/).
+
+## Deploying to Heroku
+
+```sh
+$ heroku create
+$ git push heroku master
+
+$ heroku run python manage.py migrate
+$ heroku open
+```
+or
+
+[![Deploy](https://www.herokucdn.com/deploy/button.svg)](https://heroku.com/deploy)
+
+## Documentation
+
+For more information about using Python on Heroku, see these Dev Center articles:
+
+- [Python on Heroku](https://devcenter.heroku.com/categories/python)
@@ -0,0 +1,22 @@
+{
+  "name": "Start on Heroku: Python",
+  "description": "A barebones Python app, which can easily be deployed to Heroku.",
+  "image": "heroku/python",
+  "repository": "https://github.com/heroku/python-getting-started",
+  "keywords": ["python", "django" ],
+  "addons": [ "heroku-postgresql" ],
+  "env": {
+    "SECRET_KEY": {
+      "description": "The secret key for the Django application.",
+      "generator": "secret"
+    }
+  },
+  "environments": {
+    "test": {
+      "scripts": {
+        "test-setup": "python manage.py collectstatic --noinput",
+        "test": "python manage.py test"
+      }
+    }
+  }
+}
@@ -0,0 +1,125 @@
+"""
+Django settings for gettingstarted project.
+
+Generated by 'django-admin startproject' using Django 2.0.
+
+For more information on this file, see
+https://docs.djangoproject.com/en/2.0/topics/settings/
+
+For the full list of settings and their values, see
+https://docs.djangoproject.com/en/2.0/ref/settings/
+"""
+
+import os
+import django_heroku
+
+
+# Build paths inside the project like this: os.path.join(BASE_DIR, ...)
+BASE_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
+
+
+# Quick-start development settings - unsuitable for production
+# See https://docs.djangoproject.com/en/2.0/howto/deployment/checklist/
+
+# SECURITY WARNING: keep the secret key used in production secret!
+SECRET_KEY = 'CHANGE_ME!!!! (P.S. the SECRET_KEY environment variable will be used, if set, instead).'
+
+# SECURITY WARNING: don't run with debug turned on in production!
+DEBUG = True
+
+ALLOWED_HOSTS = []
+
+
+# Application definition
+
+INSTALLED_APPS = [
+    'django.contrib.admin',
+    'django.contrib.auth',
+    'django.contrib.contenttypes',
+    'django.contrib.sessions',
+    'django.contrib.messages',
+    'django.contrib.staticfiles',
+    'hello'
+]
+
+MIDDLEWARE = [
+    'django.middleware.security.SecurityMiddleware',
+    'django.contrib.sessions.middleware.SessionMiddleware',
+    'django.middleware.common.CommonMiddleware',
+    'django.middleware.csrf.CsrfViewMiddleware',
+    'django.contrib.auth.middleware.AuthenticationMiddleware',
+    'django.contrib.messages.middleware.MessageMiddleware',
+    'django.middleware.clickjacking.XFrameOptionsMiddleware',
+]
+
+ROOT_URLCONF = 'gettingstarted.urls'
+
+TEMPLATES = [
+    {
+        'BACKEND': 'django.template.backends.django.DjangoTemplates',
+        'DIRS': [],
+        'APP_DIRS': True,
+        'OPTIONS': {
+            'context_processors': [
+                'django.template.context_processors.debug',
+                'django.template.context_processors.request',
+                'django.contrib.auth.context_processors.auth',
+                'django.contrib.messages.context_processors.messages',
+            ],
+        },
+    },
+]
+
+WSGI_APPLICATION = 'gettingstarted.wsgi.application'
+
+
+# Database
+# https://docs.djangoproject.com/en/2.0/ref/settings/#databases
+
+DATABASES = {
+    'default': {
+        'ENGINE': 'django.db.backends.sqlite3',
+        'NAME': os.path.join(BASE_DIR, 'db.sqlite3'),
+    }
+}
+
+
+# Password validation
+# https://docs.djangoproject.com/en/2.0/ref/settings/#auth-password-validators
+
+AUTH_PASSWORD_VALIDATORS = [
+    {
+        'NAME': 'django.contrib.auth.password_validation.UserAttributeSimilarityValidator',
+    },
+    {
+        'NAME': 'django.contrib.auth.password_validation.MinimumLengthValidator',
+    },
+    {
+        'NAME': 'django.contrib.auth.password_validation.CommonPasswordValidator',
+    },
+    {
+        'NAME': 'django.contrib.auth.password_validation.NumericPasswordValidator',
+    },
+]
+
+
+# Internationalization
+# https://docs.djangoproject.com/en/2.0/topics/i18n/
+
+LANGUAGE_CODE = 'en-us'
+
+TIME_ZONE = 'UTC'
+
+USE_I18N = True
+
+USE_L10N = True
+
+USE_TZ = True
+
+
+# Static files (CSS, JavaScript, Images)
+# https://docs.djangoproject.com/en/2.0/howto/static-files/
+
+STATIC_URL = '/static/'
+
+django_heroku.settings(locals())
@@ -0,0 +1,17 @@
+from django.conf.urls import include, url
+from django.urls import path
+
+from django.contrib import admin
+admin.autodiscover()
+
+import hello.views
+
+# Examples:
+# url(r'^$', 'gettingstarted.views.home', name='home'),
+# url(r'^blog/', include('blog.urls')),
+
+urlpatterns = [
+    url(r'^$', hello.views.index, name='index'),
+    url(r'^db', hello.views.db, name='db'),
+    path('admin/', admin.site.urls),
+]
@@ -0,0 +1,15 @@
+"""
+WSGI config for gettingstarted project.
+
+It exposes the WSGI callable as a module-level variable named ``application``.
+
+For more information on this file, see
+https://docs.djangoproject.com/en/1.6/howto/deployment/wsgi/
+"""
+
+import os
+os.environ.setdefault("DJANGO_SETTINGS_MODULE", "gettingstarted.settings")
+
+from django.core.wsgi import get_wsgi_application
+
+application = get_wsgi_application()
@@ -0,0 +1,3 @@
+from django.contrib import admin
+
+# Register your models here.
@@ -0,0 +1,23 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.9.1 on 2016-01-27 21:54
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    initial = True
+
+    dependencies = [
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='Greeting',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('when', models.DateTimeField(auto_now_add=True, verbose_name=b'date created')),
+            ],
+        ),
+    ]
--- a/Show More
+++ b/Show More
				`@@ -0,0 +1 @@`
				`web: python manage.py runserver 0.0.0.0:5000`