admin,storage: added more administrator functionalities

administrators can now:
 - Set displayname of users
 - Update user avatars
 - Search for users by user_id
 - Browse all users in a paginated API
 - Reset user passwords
 - Deactivate users

Helpers for doing paginated queries has also been added to storage

Signed-off-by: Morteza Araby <morteza.araby@ericsson.com>

synapse/storage/__init__.py

@@ -297,6 +297,82 @@ class DataStore(RoomMemberStore, RoomStore,
             desc="get_user_ip_and_agents",
         )
 
+    def get_users(self):
+        """Function to reterive a list of users in users table.
+
+        Args:
+        Returns:
+            defer.Deferred: resolves to list[dict[str, Any]]
+        """
+        return self._simple_select_list(
+            table="users",
+            keyvalues={},
+            retcols=[
+                "name",
+                "password_hash",
+                "is_guest",
+                "admin"
+            ],
+            desc="get_users",
+        )
+
+    def get_users_paginate(self, order, start, limit):
+        """Function to reterive a paginated list of users from
+        users list. This will return a json object, which contains
+        list of users and the total number of users in users table.
+
+        Args:
+            order (str): column name to order the select by this column
+            start (int): start number to begin the query from
+            limit (int): number of rows to reterive
+        Returns:
+            defer.Deferred: resolves to json object {list[dict[str, Any]], count}
+        """
+        is_guest = 0
+        i_start = (int)(start)
+        i_limit = (int)(limit)
+        return self.get_user_list_paginate(
+            table="users",
+            keyvalues={
+                "is_guest": is_guest
+            },
+            pagevalues=[
+                order,
+                i_limit,
+                i_start
+            ],
+            retcols=[
+                "name",
+                "password_hash",
+                "is_guest",
+                "admin"
+            ],
+            desc="get_users_paginate",
+        )
+
+    def search_users(self, term):
+        """Function to search users list for one or more users with
+        the matched term.
+
+        Args:
+            term (str): search term
+            col (str): column to query term should be matched to
+        Returns:
+            defer.Deferred: resolves to list[dict[str, Any]]
+        """
+        return self._simple_search_list(
+            table="users",
+            term=term,
+            col="name",
+            retcols=[
+                "name",
+                "password_hash",
+                "is_guest",
+                "admin"
+            ],
+            desc="search_users",
+        )
+
 
 def are_all_users_on_domain(txn, database_engine, domain):
     sql = database_engine.convert_param_style(