1) Added support for authentication via the web server (REMOTE_USER). Fixes #6657

2) Fixed OAuth2 integration redirect issue. Fixes #6719

Initial patch for 6657 sent by: Tom Schreiber

web/pgadmin/browser/tests/test_kerberos_with_mocking.py

@@ -133,4 +133,5 @@ class KerberosLoginMockTestCase(BaseTestGenerator):
         """
         cls.tester.logout()
         app_config.AUTHENTICATION_SOURCES = [INTERNAL]
+        app_config.PGADMIN_EXTERNAL_AUTH_SOURCE = INTERNAL
         utils.login_tester_account(cls.tester)

web/pgadmin/browser/tests/test_ldap_login.py

@@ -95,4 +95,5 @@ class LDAPLoginTestCase(BaseTestGenerator):
         """
         cls.tester.logout()
         app_config.AUTHENTICATION_SOURCES = [INTERNAL]
+        app_config.PGADMIN_EXTERNAL_AUTH_SOURCE = INTERNAL
         utils.login_tester_account(cls.tester)

web/pgadmin/browser/tests/test_ldap_with_mocking.py

@@ -81,4 +81,5 @@ class LDAPLoginMockTestCase(BaseTestGenerator):
         """
         cls.tester.logout()
         app_config.AUTHENTICATION_SOURCES = [INTERNAL]
+        app_config.PGADMIN_EXTERNAL_AUTH_SOURCE = INTERNAL
         utils.login_tester_account(cls.tester)

web/pgadmin/browser/tests/test_login.py

@@ -100,6 +100,7 @@ class LoginTestCase(BaseTestGenerator):
     # No need to call base class setup function
     def setUp(self):
         app_config.AUTHENTICATION_SOURCES = [INTERNAL]
+        app_config.PGADMIN_EXTERNAL_AUTH_SOURCE = INTERNAL
 
     def runTest(self):
         """This function checks login functionality."""

web/pgadmin/browser/tests/test_oauth2_with_mocking.py

@@ -145,4 +145,5 @@ class Oauth2LoginMockTestCase(BaseTestGenerator):
         """
         cls.tester.logout()
         app_config.AUTHENTICATION_SOURCES = [INTERNAL]
+        app_config.PGADMIN_EXTERNAL_AUTH_SOURCE = INTERNAL
         utils.login_tester_account(cls.tester)

web/pgadmin/browser/tests/test_webserver_with_mocking.py

@@ -0,0 +1,86 @@
+##########################################################################
+#
+# pgAdmin 4 - PostgreSQL Tools
+#
+# Copyright (C) 2013 - 2021, The pgAdmin Development Team
+# This software is released under the PostgreSQL Licence
+#
+##########################################################################
+
+import config as app_config
+from pgadmin.utils.route import BaseTestGenerator
+from regression.python_test_utils import test_utils as utils
+from pgadmin.authenticate.registry import AuthSourceRegistry
+from unittest.mock import patch, MagicMock
+from pgadmin.authenticate import AuthSourceManager
+from pgadmin.utils.constants import OAUTH2, LDAP, INTERNAL, WEBSERVER
+from flask import request
+
+
+class WebserverLoginMockTestCase(BaseTestGenerator):
+    """
+    This class checks oauth2  login functionality by mocking
+    Webserver Authentication.
+    """
+
+    scenarios = [
+        ('Webserver Authentication', dict(
+            auth_source=[WEBSERVER],
+            username='test_mock_webserver_user'
+        )),
+    ]
+
+    @classmethod
+    def setUpClass(cls):
+        """
+        We need to logout the test client as we are testing
+        spnego/kerberos login scenarios.
+        """
+        cls.tester.logout()
+
+    def setUp(self):
+        app_config.AUTHENTICATION_SOURCES = self.auth_source
+        self.app.PGADMIN_EXTERNAL_AUTH_SOURCE = WEBSERVER
+
+    def runTest(self):
+        """This function checks webserver login functionality."""
+        if app_config.SERVER_MODE is False:
+            self.skipTest(
+                "Can not run Webserver Authentication in the Desktop mode."
+            )
+
+        self.test_webserver_authentication()
+
+    def test_webserver_authentication(self):
+        """
+        Ensure that when the client sends an correct authorization token,
+        they receive a 200 OK response and the user principal is extracted and
+        passed on to the routed method.
+        """
+
+        # Mock Oauth2 Authenticate
+        AuthSourceRegistry._registry[WEBSERVER].get_user = MagicMock(
+            return_value=self.username)
+
+        res = self.tester.login(None,
+                                None,
+                                True,
+                                None
+                                )
+        self.assertEqual(res.status_code, 200)
+        respdata = 'Gravatar image for %s' % self.username
+        self.assertTrue(respdata in res.data.decode('utf8'))
+
+    def tearDown(self):
+        pass
+
+    @classmethod
+    def tearDownClass(cls):
+        """
+        We need to again login the test client as soon as test scenarios
+        finishes.
+        """
+        cls.tester.logout()
+        app_config.AUTHENTICATION_SOURCES = [INTERNAL]
+        app_config.PGADMIN_EXTERNAL_AUTH_SOURCE = INTERNAL
+        utils.login_tester_account(cls.tester)