Ability to get all pages from tower_cli {resource} list.

This commit adds the ability to send `-a` or `--all-pages` to
`tower_cli {resource} list`, and it sends back all pages the API sends
down, if there is more than one page.

lib/tower_cli/models/base.py

@@ -578,9 +578,14 @@ class Resource(BaseResource):
         return response['results'][0]
 
     @resources.command(ignore_defaults=True, no_args_is_help=False)
-    @click.option('--page', default=1, type=int, help='The page to show.',
-                            show_default=True)
-    def list(self, **kwargs):
+    @click.option('all_pages', '-a', '--all-pages',
+                  is_flag=True, default=False, show_default=True,
+                  help='If set, collate all pages of content from the API '
+                       'when returning results.')
+    @click.option('--page', default=1, type=int, show_default=True,
+                            help='The page to show. Ignored if --all-pages '
+                                 'is sent.')
+    def list(self, all_pages=False, **kwargs):
         """Return a list of objects.
 
         If one or more filters are provided through keyword arguments,
@@ -588,6 +593,11 @@ class Resource(BaseResource):
 
         If no filters are provided, return all results.
         """
+        # If the `all_pages` flag is set, then ignore any page that might
+        # also be sent.
+        if all_pages:
+            kwargs.pop('page', None)
+
         # Get the response.
         debug.log('Getting records.', header='details')
         response = self.read(**kwargs)
@@ -600,6 +610,14 @@ class Resource(BaseResource):
             match = re.search(r'page=(?P<num>[\d]+)', response[key])
             response[key] = int(match.groupdict()['num'])
 
+        # If we were asked for all pages, keep retrieving pages until we
+        # have them all.
+        if all_pages and response['next']:
+            cursor = copy(response)
+            while cursor['next']:
+                cursor = self.list(**dict(kwargs, page=cursor['next']))
+                response['results'] += cursor['results']
+
         # Done; return the response
         return response
 

tests/test_models_base.py

@@ -391,6 +391,29 @@ class ResourceTests(unittest.TestCase):
             self.assertEqual(result['count'], 2)
             self.assertEqual(result['results'][0]['id'], 1)
 
+    def test_list_all_pages(self):
+        """Establish that the Resource class' `list` method correctly
+        accepts the --all-pages flag and checks follow-up pages.
+        """
+        with client.test_mode as t:
+            # Register the first, second, and third page.
+            t.register_json('/foo/', {'count': 3, 'results': [
+                {'id': 1, 'name': 'foo', 'description': 'bar'},                
+            ], 'next': '/foo/?page=2', 'previous': None})
+            t.register_json('/foo/?page=2', {'count': 3, 'results': [
+                {'id': 2, 'name': 'spam', 'description': 'eggs'},                
+            ], 'next': '/foo/?page=3', 'previous': None})
+            t.register_json('/foo/?page=3', {'count': 3, 'results': [
+                {'id': 3, 'name': 'bacon', 'description': 'cheese'},
+            ], 'next': None, 'previous': None})
+
+            # Get the list
+            result = self.res.list(all_pages=True)
+
+            # Assert that there are three results, and three requests.
+            self.assertEqual(len(t.requests), 3)
+            self.assertEqual(len(result['results']), 3)
+
     def test_get_unexpected_zero_results(self):
         """Establish that if a read method gets 0 results when it should have
         gotten one or more, that it raises NotFound.