Implement feature that allows to export tabular data suited to a… (#437)

docs/formats.rst

@@ -7,6 +7,29 @@ Formats
 Tablib supports a wide variety of different tabular formats, both for input and
 output. Moreover, you can :ref:`register your own formats <newformats>`.
 
+cli
+===
+
+The ``cli`` format is currently export-only. The exports produce a representation
+table suited to a terminal.
+
+When exporting to a CLI you can pass the table format  with the ``tablefmt``
+parameter, the supported formats are::
+
+    >>> import tabulate
+    >>> list(tabulate._table_formats)
+    ['simple', 'plain', 'grid', 'fancy_grid', 'github', 'pipe', 'orgtbl',
+     'jira', 'presto', 'psql', 'rst', 'mediawiki', 'moinmoin', 'youtrack',
+     'html', 'latex', 'latex_raw', 'latex_booktabs', 'tsv', 'textile']
+
+For example::
+
+    dataset.export("cli", tablefmt="github")
+    dataset.export("cli", tablefmt="grid")
+
+This format is optional, install Tablib with ``pip install tablib[cli]`` to
+make the format available.
+
 csv
 ===
 
@@ -100,7 +123,7 @@ latex
 
 Import/export using the LaTeX_ format. This format is export-only.
 If a title has been set, it will be exported as the table caption.
- 
+
 .. _LaTeX: https://www.latex-project.org/
 
 ods

setup.py

@@ -33,7 +33,8 @@ setup(
     ],
     python_requires='>=3.5',
     extras_require={
-        'all': ['markuppy', 'odfpy', 'openpyxl>=2.4.0', 'pandas', 'pyyaml', 'xlrd', 'xlwt'],
+        'all': ['markuppy', 'odfpy', 'openpyxl>=2.4.0', 'pandas', 'pyyaml', 'tabulate', 'xlrd', 'xlwt'],
+        'cli': ['tabulate'],
         'html': ['markuppy'],
         'ods': ['odfpy'],
         'pandas': ['pandas'],

src/tablib/formats/__init__.py

@@ -12,6 +12,10 @@ from ._json import JSONFormat
 from ._tsv import TSVFormat
 
 uninstalled_format_messages = {
+    'cli': (
+        "The 'cli' format is not available. You may want to install the tabulate "
+        "package (or `pip install tablib[cli]`)."
+    ),
     'df': (
         "The 'df' format is not available. You may want to install the pandas "
         "package (or `pip install tablib[pandas]`)."
@@ -88,7 +92,7 @@ class Registry:
     def register(self, key, format_or_path):
         from tablib.core import Databook, Dataset
 
-        # Create Databook.<format> read or read/write properties 
+        # Create Databook.<format> read or read/write properties
         setattr(Databook, key, ImportExportBookDescriptor(key, format_or_path))
 
         # Create Dataset.<format> read or read/write properties,
@@ -124,6 +128,8 @@ class Registry:
         if find_spec('pandas'):
             self.register('df', 'tablib.formats._df.DataFrameFormat')
         self.register('rst', 'tablib.formats._rst.ReSTFormat')
+        if find_spec('tabulate'):
+            self.register('cli', 'tablib.formats._cli.CLIFormat')
 
     def formats(self):
         for key, frm in self._formats.items():

src/tablib/formats/_cli.py

@@ -0,0 +1,20 @@
+"""Tablib - Command-line Interface table export support.
+
+   Generates a representation for CLI from the dataset.
+   Wrapper for tabulate library.
+"""
+from tabulate import tabulate as Tabulate
+
+
+class CLIFormat:
+    """ Class responsible to export to CLI Format """
+    title = 'cli'
+    DEFAULT_FMT = 'plain'
+
+    @classmethod
+    def export_set(cls, dataset, **kwargs):
+        """Returns CLI representation of a Dataset."""
+        if dataset.headers:
+            kwargs.setdefault('headers', dataset.headers)
+        kwargs.setdefault('tablefmt', cls.DEFAULT_FMT)
+        return Tabulate(dataset, **kwargs)

tests/requirements.txt

@@ -5,5 +5,6 @@ odfpy
 openpyxl>=2.4.0
 pandas
 pyyaml
+tabulate
 xlrd
 xlwt

tests/test_tablib.py

@@ -1288,3 +1288,14 @@ class DocTests(unittest.TestCase):
         import tablib.formats._rst
         results = doctest.testmod(tablib.formats._rst)
         self.assertEqual(results.failed, 0)
+
+
+class CliTests(BaseTestCase):
+    def test_cli_export_github(self):
+        self.assertEqual('|---|---|---|\n| a | b | c |', tablib.Dataset(['a','b','c']).export('cli', tablefmt='github'))
+
+    def test_cli_export_simple(self):
+        self.assertEqual('-  -  -\na  b  c\n-  -  -', tablib.Dataset(['a','b','c']).export('cli', tablefmt='simple'))
+
+    def test_cli_export_grid(self):
+        self.assertEqual('+---+---+---+\n| a | b | c |\n+---+---+---+', tablib.Dataset(['a','b','c']).export('cli', tablefmt='grid'))