added gitlab authentication with documentation

Author: feyruzb

docs/web/authentication.md

@@ -415,6 +415,11 @@ Specific behavior related to each provider is configured by a provider `template
           * `username` - Company's signum will be the user's identifier.
           * `email` - an email associated with this Microsoft account will be used as user's identifier.
 
+        `gitlab/v1`
+          * `username` - the username the user prefers to be referred to as, usually their login or the login from the authentication provider.
+          * `email` - an email associated with this Gitlab account will be used as user's identifier.
+          * `name` - user's full name.
+
       The properties below are automatically set by templates, but can be overridden for testing purposes, and when using a custom OAuth provider.
 
       * `callback_url`

web/codechecker_web/server/oauth_templates.py

@@ -46,5 +46,15 @@
         "user_info_mapping": {
             "username": "email"
         }
+    },
+    "gitlab/v1": {
+        "authorization_url": "https://gitlab.com/oauth/authorize",
+        "callback_url": "{host}/login/OAuthLogin/{provider}",
+        "token_url": "https://gitlab.com/oauth/token",
+        "user_info_url": "https://gitlab.com/oauth/userinfo",
+        "scope": "openid email profile",
+        "user_info_mapping": {
+            "username": "email"
+        }
     }
 }

web/server/codechecker_server/api/authentication.py

@@ -484,9 +484,17 @@ def performLogin(self, auth_method, auth_string):
                         username = claims.get("Signum")
                     else:
                         username = user_info.get("mail")
+                elif template == "gitlab/v1":
+                    print(user_info)
+                    if username_key == "username":
+                        username = user_info.get("preferred_username")
+                    elif username_key == "email":
+                        print(user_info)
+                        username = user_info.get("email")
+                    elif username_key == "name":
+                        username = user_info.get("name")
 
                 LOG.debug(f"groups fetched for {username}, are: {groups}")
-
                 LOG.info("Username fetched, for username: %s", username)
             except Exception as ex:
                 LOG.error("Username fetch failed: %s", str(ex))

web/server/config/server_config.json

@@ -82,6 +82,12 @@
           "variables": {
             "tenant_id": "common"
           }
+        },
+        "gitlab": {
+          "enabled": false,
+          "client_id": "<ExampleClientID>",
+          "client_secret": "<ExampleClientSecret>",
+          "template": "gitlab/v1"
         }
       }
     },