python-for-humans/2_problem/0_problem.md

!SLIDE

Part II: Beginnings

So, let's say we're new to Python.

Let's get started!

!SLIDE

Step 1: Pick a Release.

Pick carefully.

!SLIDE incremental

Step 2: Install Python.

Decisions, decisions.

• Download installer from python.org?
• 32bit or 64bit?
• Build from source?
• If so, Unix or framework build?

!SLIDE

Step 3: Profit!

Let's play around. Maybe play with the GitHub API?

!SLIDE small code execute

Ruby.

@@@ ruby
require 'net/http'
require 'uri'

uri = URI.parse('https://api.github.com/user')

http = Net::HTTP.new(uri.host, uri.port)
http.use_ssl = true

req = Net::HTTP::Get.new(uri.request_uri)
req.basic_auth('username', 'password')

r = http.request(req)

puts r

!SLIDE

http/url/lib/2

• Extremely unclear why there are so many modules.
• Search implies urllib2.
• Let's give this a shot...

!SLIDE smaller code execute

Python (hours later).

@@@ python
import urllib2

gh_url = 'https://api.github.com/user'

req = urllib2.Request(gh_url)

password_manager = urllib2.HTTPPasswordMgrWithDefaultRealm()
password_manager.add_password(None, gh_url, 'user', 'pass')

auth_manager = urllib2.HTTPBasicAuthHandler(password_manager)
opener = urllib2.build_opener(auth_manager)

urllib2.install_opener(opener)

handler = urllib2.urlopen(req)

print handler.read()

!SLIDE smaller code execute #But wait — there's more!

@@@ python

import re

class HTTPForcedBasicAuthHandler(HTTPBasicAuthHandler):

    auth_header = 'Authorization'
    rx = re.compile('(?:.*,)*[ \t]*([^ \t]+)[ \t]+'
                    'realm=(["\'])(.*?)\\2', re.I)

    def __init__(self,  *args, **kwargs):
        HTTPBasicAuthHandler.__init__(self, *args, **kwargs)s

    def http_error_401(self, req, fp, code, msg, headers):
        url = req.get_full_url()
        response = self._http_error_auth_reqed(
            'www-authenticate', url, req, headers)
        self.reset_retry_count()
        return response

    http_error_404 = http_error_401

!SLIDE

Admit it.

If this was you, you'd leave Python and never come back.

!SLIDE

http/url/lib/2

• Which module to use?
• Worst API ever.
• An extremely common use case.
• I'd rather be writing ColdFusion™.

!SLIDE

XML

• etree is terrible.
• lxml is awesome, but difficult to install.

!SLIDE

File and System Operations

• sys | shutils | os | os.path | io
• Really difficult to run external commands.
• This blocks dev+ops folks from adopting Python.

!SLIDE

Packaging and Depdencies

• pip or easy install?
• setuptools isn't included with python? Distribute?
• No easy_uninstall?
• Broken setup.pys
• "Released" packages not in the Cheeseshop

!SLIDE

Date[time]s.

• Which module to use?
• Timezones
• The stdlib can generate but not parse ISO8601 dates

!SLIDE

Unicode.

• LOLWUT

!SLIDE

Testing.

!SLIDE

Installing Dependencies

• Pip? Virtualenv? Never mentioned in the docs.
• python-mysql
• mod_wsgi

!SLIDE

Integration Time

!SLIDE

PIL

(On OSX, this is simple)