Repository: googleapis/google-cloud-python

Issue:
Automatically check if modules are left out of the API docs
See [previous comment](https://github.com/GoogleCloudPlatform/gcloud-python/issues/707#issuecomment-78552001) for context.



Discussion:
/cc @tseaver We may be able to handle this with http://sphinx-doc.org/ext/coverage.html

I will try to enable `sphinx.ext.coverage`.

Per [Takayuki Shimizukawa's EP 2015 presentation](https://youtu.be/mdtxHjH2wog?t=1407), the extension generates a ReST report for undocumented modules/classes/functions, but there is no CI integration for it:  the command always succeeds, and does not generate a useful machine-readable file we could interrogate.

I have a hacky but short way to check this.

``` python
import os
import warnings

from sphinx.ext.intersphinx import fetch_inventory

class SphinxApp(object):
    warn = warnings.warn
    srcdir = os.path.abspath('.')

I = fetch_inventory(SphinxApp, '',
                    os.path.join('docs', '_build', 'html', 'objects.inv'))
sphinx_mods = I['py:module'].keys()

py_files = []
for path, _, files in os.walk('gcloud'):
    if any([part.startswith('_')
            for part in path.split(os.path.sep)]):
        continue
    for fi in files:
        if (fi.endswith('.py') and not fi.startswith('test_')
                and not fi.startswith('_')):
            py_files.append(os.path.join(path, fi))
mods = [fi[:-3].replace(os.path.sep, '.') for fi in py_files]
print set(sphinx_mods) - set(mods)
print set(mods) - set(sphinx_mods)
```

---

Running this results in an empty set (everything in `sphinx_mods` is in `mods`) and the following:

``` python
{'gcloud.bigquery.query',
 'gcloud.bigtable.client',
 'gcloud.bigtable.cluster',
 'gcloud.bigtable.column_family',
 'gcloud.bigtable.row',
 'gcloud.bigtable.table',
 'gcloud.datastore.demo.demo',
 'gcloud.datastore.helpers',
 'gcloud.demo',
 'gcloud.environment_vars',
 'gcloud.iterator',
 'gcloud.storage.batch',
 'gcloud.storage.demo.demo',
 'gcloud.streaming.buffered_stream',
 'gcloud.streaming.exceptions',
 'gcloud.streaming.http_wrapper',
 'gcloud.streaming.stream_slice',
 'gcloud.streaming.transfer',
 'gcloud.streaming.util'}
```

We could do as we do in `run_pylint.py` and [manually specify](https://github.com/GoogleCloudPlatform/gcloud-python/blob/f220a36f129f35731de4aee25e7032f5b58db4a6/run_pylint.py#L34-L38) which files we are happy to ignore.

---

@tseaver WDYT?


Resolving patch:
diff --git a/scripts/run_pylint.py b/scripts/run_pylint.py
--- a/scripts/run_pylint.py
+++ b/scripts/run_pylint.py
@@ -21,6 +21,8 @@
 violations (hence it has a reduced number of style checks).
 """
 
+from __future__ import print_function
+
 import ConfigParser
 import copy
 import os
@@ -152,12 +154,12 @@ def get_files_for_linting(allow_limited=True):
     if diff_base is not None and allow_limited:
         result = subprocess.check_output(['git', 'diff', '--name-only',
                                           diff_base])
-        print 'Using files changed relative to %s:' % (diff_base,)
-        print '-' * 60
-        print result.rstrip('\n')  # Don't print trailing newlines.
-        print '-' * 60
+        print('Using files changed relative to %s:' % (diff_base,))
+        print('-' * 60)
+        print(result.rstrip('\n'))  # Don't print trailing newlines.
+        print('-' * 60)
     else:
-        print 'Diff base not specified, listing all files in repository.'
+        print('Diff base not specified, listing all files in repository.')
         result = subprocess.check_output(['git', 'ls-files'])
 
     return result.rstrip('\n').split('\n'), diff_base
@@ -212,10 +214,10 @@ def lint_fileset(filenames, rcfile, description):
         if status_code != 0:
             error_message = ('Pylint failed on %s with '
                              'status %d.' % (description, status_code))
-            print >> sys.stderr, error_message
+            print(error_message, file=sys.stderr)
             sys.exit(status_code)
     else:
-        print 'Skipping %s, no files to lint.' % (description,)
+        print('Skipping %s, no files to lint.' % (description,))
 
 
 def main():
@@ -230,7 +232,7 @@ def main():
             raise
 
         message = 'Restricted lint failed, expanding to full fileset.'
-        print >> sys.stderr, message
+        print(message, file=sys.stderr)
         all_files, _ = get_files_for_linting(allow_limited=False)
         library_files, non_library_files, _ = get_python_files(
             all_files=all_files)
diff --git a/scripts/verify_included_modules.py b/scripts/verify_included_modules.py
new file mode 100644
--- /dev/null
+++ b/scripts/verify_included_modules.py
@@ -0,0 +1,141 @@
+# Copyright 2016 Google Inc. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Check if all public modules are included in our docs."""
+
+
+from __future__ import print_function
+
+import os
+import sys
+import warnings
+
+from sphinx.ext.intersphinx import fetch_inventory
+
+
+BASE_DIR = os.path.abspath(
+    os.path.join(os.path.dirname(__file__), '..'))
+DOCS_DIR = os.path.join(BASE_DIR, 'docs')
+OBJECT_INVENTORY_RELPATH = os.path.join('_build', 'html', 'objects.inv')
+IGNORED_PREFIXES = ('test_', '_')
+IGNORED_MODULES = frozenset([
+    'gcloud.bigtable.client',
+    'gcloud.bigtable.cluster',
+    'gcloud.bigtable.column_family',
+    'gcloud.bigtable.happybase.connection',
+    'gcloud.bigtable.row',
+    'gcloud.bigtable.table',
+    'gcloud.datastore.demo.demo',
+    'gcloud.demo',
+    'gcloud.iterator',
+    'gcloud.storage.demo.demo',
+    'gcloud.streaming.buffered_stream',
+    'gcloud.streaming.exceptions',
+    'gcloud.streaming.http_wrapper',
+    'gcloud.streaming.stream_slice',
+    'gcloud.streaming.transfer',
+    'gcloud.streaming.util',
+])
+
+
+class SphinxApp(object):
+    """Mock app to interact with Sphinx helpers."""
+    warn = warnings.warn
+    srcdir = DOCS_DIR
+
+
+def is_valid_module(filename):
+    """Determines if a filename is a valid Python module.
+
+    Assumes if is just the end of a path (i.e. does not contain
+    ``os.path.sep``.
+
+    :type filename: string
+    :param filename: The name of a file.
+
+    :rtype: bool
+    :returns: Flag indicating if the filename is valid.
+    """
+    if not filename.endswith('.py'):
+        return False
+    for prefix in IGNORED_PREFIXES:
+        if filename.startswith(prefix):
+            return False
+    return True
+
+
+def get_public_modules(path, base_package=None):
+    """Get list of all public modules relative to a path.
+
+    :type path: string
+    :param path: The path containing the python modules.
+
+    :type base_package: string
+    :param base_package: (Optional) A package to prepend in
+                         front of the path.
+
+    :rtype: list
+    :returns: List of all modules found.
+    """
+    result = []
+    for subdir, _, files in os.walk(path):
+        # Skip folders that start with _.
+        if any([part.startswith('_')
+                for part in subdir.split(os.path.sep)]):
+            continue
+        _, rel_dir = subdir.split(path)
+        rel_dir = rel_dir.lstrip(os.path.sep)
+        for filename in files:
+            if is_valid_module(filename):
+                mod_name, _ = os.path.splitext(filename)
+                rel_path = os.path.join(rel_dir, mod_name)
+                if base_package is not None:
+                    rel_path = os.path.join(base_package, rel_path)
+                # Turn into a Python module rather than a file path.
+                result.append(rel_path.replace(os.path.sep, '.'))
+
+    return result
+
+
+def main():
+    """Main script to verify modules included."""
+    mock_uri = ''
+    inventory = fetch_inventory(SphinxApp, mock_uri,
+                                OBJECT_INVENTORY_RELPATH)
+    sphinx_mods = set(inventory['py:module'].keys())
+
+    library_dir = os.path.join(BASE_DIR, 'gcloud')
+    public_mods = get_public_modules(library_dir,
+                                     base_package='gcloud')
+    public_mods = set(public_mods)
+
+    if not sphinx_mods <= public_mods:
+        message = ('Unexpected error. There were modules referenced by '
+                   'Sphinx that are not among the public modules.')
+        print(message, file=sys.stderr)
+        sys.exit(1)
+
+    undocumented_mods = public_mods - sphinx_mods
+    # Remove ignored modules.
+    undocumented_mods -= IGNORED_MODULES
+    if undocumented_mods:
+        message_parts = ['Found undocumented public modules:']
+        message_parts.extend(['- ' + mod_name
+                              for mod_name in sorted(undocumented_mods)])
+        print('\n'.join(message_parts), file=sys.stderr)
+        sys.exit(1)
+
+
+if __name__ == '__main__':
+    main()


Test patch: