gitlab.lister: Simplify retrieving headers information

As response headers' keys are case-insensitive and requests does the
aggregation magic.

[1] http://docs.python-requests.org/en/master/user/quickstart/#response-headers

swh/lister/gitlab/lister.py

@@ -94,13 +94,16 @@ class GitLabLister(PageByPageHttpLister):
                 return True, delay
         return False, 0
 
+    def _get_int(self, headers, key):
+        _val = headers.get(key)
+        if _val:
+            return int(_val)
+
     def get_next_target_from_response(self, response):
         """Determine the next page identifier.
 
         """
-        _next = utils.get(response.headers, ['X-Next-Page', 'x-next-page'])
-        if _next:
-            return int(_next)
+        return self._get_int(response.headers, 'x-next-page')
 
     def get_pages_information(self):
         """Determine pages information.
@@ -108,16 +111,9 @@ class GitLabLister(PageByPageHttpLister):
         """
         response = self.transport_head(identifier=1)
         h = response.headers
-        total = utils.get(h, ['X-Total', 'x-total'])
-        total_pages = utils.get(h, ['X-Total-Pages', 'x-total-pages'])
-        per_page = utils.get(h, ['X-Per-Page', 'x-per-page'])
-        if total is not None:
-            total = int(total)
-        if total_pages is not None:
-            total_pages = int(total_pages)
-        if per_page is not None:
-            per_page = int(per_page)
-        return total, total_pages, per_page
+        return (self._get_int(h, 'x-total'),
+                self._get_int(h, 'x-total-pages'),
+                self._get_int('x-per-page'))
 
     def transport_response_simplified(self, response):
         repos = response.json()

swh/lister/tests/test_utils.py

@@ -11,45 +11,6 @@ from swh.lister import utils
 
 class UtilsTest(unittest.TestCase):
 
-    @istest
-    def get(self):
-        data = {
-            'X-Next-Page': None,
-            'x-next-page': 1,
-        }
-        actual_value = utils.get(data, ['X-Next-Page', 'x-next-page'])
-
-        self.assertEqual(actual_value, 1)
-
-        data = {
-            'X-Next-Page': 10,
-            'x-next-page': 1,
-        }
-        actual_value = utils.get(data, ['X-Next-Page', 'x-next-page'])
-
-        self.assertEqual(actual_value, 10)
-
-        data = {
-            'x-next-page': 100,
-        }
-        actual_value = utils.get(data, ['X-Next-Page', 'x-next-page'])
-
-        self.assertEqual(actual_value, 100)
-
-    @istest
-    def get_empty(self):
-        self.assertIsNone(utils.get({}, []))
-        self.assertIsNone(utils.get({'a': 1}, ['b']))
-        self.assertIsNone(utils.get({'b': 2}, []))
-        self.assertIsNone(utils.get({'b': 2}, []))
-
-    @istest
-    def get_errors(self):
-        with self.assertRaises(TypeError):
-            self.assertIsNone(utils.get({}, None))
-        with self.assertRaises(AttributeError):
-            self.assertIsNone(utils.get(None, ['a']))
-
     @istest
     def split_range(self):
         actual_ranges = list(utils.split_range(14, 5))

swh/lister/utils.py

@@ -3,17 +3,6 @@
 # See top-level LICENSE file for more information
 
 
-def get(d, keys):
-    """Given a dict, lookup in order for keys with values not None.
-
-    """
-    for key in keys:
-        v = d.get(key)
-        if v is not None:
-            return v
-    return None
-
-
 def split_range(total_pages, nb_pages):
     prev_index = None
     for index in range(0, total_pages, nb_pages):