# Error while trying to add Paytm Oauth using discourse-oauth2-basic plugin **URL:** \ **Category:** SSO\ **Tags:** oauth2\ **Created:** [April 12, 2023, 4:38am UTC](https://meta.discourse.org/t/error-while-trying-to-add-paytm-oauth-using-discourse-oauth2-basic-plugin/261407 "2023-04-12T04:38:04Z")\ **Posts on this page:** 1\ **Showing post:** 3
**Author:** ![sebix1](https://avatars.discourse-cdn.com/v4/letter/s/bcef8e/32.png) [@sebix1](https://meta.discourse.org/u/sebix1)\ **Post date:** [June 7, 2023, 6:04pm UTC](https://meta.discourse.org/t/error-while-trying-to-add-paytm-oauth-using-discourse-oauth2-basic-plugin/261407/3 "2023-06-07T18:04:55Z")
I experience the same error using [GitLab.com](http://GitLab.com) as oauth provider with the [discourse-oauth2-basic](https://github.com/discourse/discourse-oauth2-basic) plugin (version 0.3). The authentication at [gitlab.com](http://gitlab.com) succeeds, then I get back to discourse with the correct Redirect URI: [http://example.com/auth/oauth2\_basic/callback?code=...&state=](http://example.com/auth/oauth2_basic/callback?code=...&state=)… The error is ```plaintext NoMethodError (undefined method `downcase' for nil:NilClass) lib/final_destination/ssrf_detector.rb:81:in `block in host_bypasses_checks?' lib/final_destination/ssrf_detector.rb:81:in `any?' lib/final ``` and the traceback ```plaintext lib/final_destination/ssrf_detector.rb:81:in `block in host_bypasses_checks?' lib/final_destination/ssrf_detector.rb:81:in `any?' lib/final_destination/ssrf_detector.rb:81:in `host_bypasses_checks?' lib/final_destination/ssrf_detector.rb:100:in `lookup_and_filter_ips' lib/final_destination/http.rb:13:in `connect' /usr/local/lib/ruby/3.2.0/net/http.rb:1248:in `do_start' /usr/local/lib/ruby/3.2.0/net/http.rb:1237:in `start' faraday-net_http (3.0.2) lib/faraday/adapter/net_http.rb:112:in `request_with_wrapped_block' faraday-net_http (3.0.2) lib/faraday/adapter/net_http.rb:102:in `perform_request' faraday-net_http (3.0.2) lib/faraday/adapter/net_http.rb:66:in `block in call' faraday (2.7.5) lib/faraday/adapter.rb:45:in `connection' faraday-net_http (3.0.2) lib/faraday/adapter/net_http.rb:65:in `call' faraday (2.7.5) lib/faraday/rack_builder.rb:153:in `build_response' faraday (2.7.5) lib/faraday/connection.rb:444:in `run_request' plugins/discourse-oauth2-basic/plugin.rb:231:in `fetch_user_details' plugins/discourse-oauth2-basic/plugin.rb:278:in `after_authenticate' app/controllers/users/omniauth_callbacks_controller.rb:37:in `complete' actionpack (7.0.4.3) lib/action_controller/metal/basic_implicit_render.rb:6:in `send_action' actionpack (7.0.4.3) lib/abstract_controller/base.rb:215:in `process_action' actionpack (7.0.4.3) lib/action_controller/metal/rendering.rb:53:in `process_action' actionpack (7.0.4.3) lib/abstract_controller/callbacks.rb:234:in `block in process_action' activesupport (7.0.4.3) lib/active_support/callbacks.rb:118:in `block in run_callbacks' app/controllers/application_controller.rb:418:in `block in with_resolved_locale' i18n (1.14.1) lib/i18n.rb:322:in `with_locale' app/controllers/application_controller.rb:418:in `with_resolved_locale' activesupport (7.0.4.3) lib/active_support/callbacks.rb:127:in `block in run_callbacks' activesupport (7.0.4.3) lib/active_support/callbacks.rb:138:in `run_callbacks' actionpack (7.0.4.3) lib/abstract_controller/callbacks.rb:233:in `process_action' actionpack (7.0.4.3) lib/action_controller/metal/rescue.rb:22:in `process_action' actionpack (7.0.4.3) lib/action_controller/metal/instrumentation.rb:67:in `block in process_action' activesupport (7.0.4.3) lib/active_support/notifications.rb:206:in `block in instrument' activesupport (7.0.4.3) lib/active_support/notifications/instrumenter.rb:24:in `instrument' activesupport (7.0.4.3) lib/active_support/notifications.rb:206:in `instrument' actionpack (7.0.4.3) lib/action_controller/metal/instrumentation.rb:66:in `process_action' actionpack (7.0.4.3) lib/action_controller/metal/params_wrapper.rb:259:in `process_action' activerecord (7.0.4.3) lib/active_record/railties/controller_runtime.rb:27:in `process_action' actionpack (7.0.4.3) lib/abstract_controller/base.rb:151:in `process' actionview (7.0.4.3) lib/action_view/rendering.rb:39:in `process' rack-mini-profiler (3.1.0) lib/mini_profiler/profiling_methods.rb:85:in `block in profile_method' actionpack (7.0.4.3) lib/action_controller/metal.rb:188:in `dispatch' actionpack (7.0.4.3) lib/action_controller/metal.rb:251:in `dispatch' actionpack (7.0.4.3) lib/action_dispatch/routing/route_set.rb:49:in `dispatch' actionpack (7.0.4.3) lib/action_dispatch/routing/route_set.rb:32:in `serve' actionpack (7.0.4.3) lib/action_dispatch/journey/router.rb:50:in `block in serve' actionpack (7.0.4.3) lib/action_dispatch/journey/router.rb:32:in `each' actionpack (7.0.4.3) lib/action_dispatch/journey/router.rb:32:in `serve' actionpack (7.0.4.3) lib/action_dispatch/routing/route_set.rb:852:in `call' omniauth (1.9.2) lib/omniauth/strategy.rb:192:in `call!' omniauth (1.9.2) lib/omniauth/strategy.rb:169:in `call' omniauth (1.9.2) lib/omniauth/strategy.rb:420:in `call_app!' omniauth (1.9.2) lib/omniauth/strategy.rb:373:in `callback_phase' omniauth-oauth2 (1.7.3) lib/omniauth/strategies/oauth2.rb:93:in `callback_phase' omniauth (1.9.2) lib/omniauth/strategy.rb:238:in `callback_call' omniauth (1.9.2) lib/omniauth/strategy.rb:189:in `call!' omniauth (1.9.2) lib/omniauth/strategy.rb:169:in `call' omniauth (1.9.2) lib/omniauth/strategy.rb:192:in `call!' omniauth (1.9.2) lib/omniauth/strategy.rb:169:in `call' omniauth (1.9.2) lib/omniauth/strategy.rb:192:in `call!' omniauth (1.9.2) lib/omniauth/strategy.rb:169:in `call' omniauth (1.9.2) lib/omniauth/strategy.rb:192:in `call!' omniauth (1.9.2) lib/omniauth/strategy.rb:169:in `call' omniauth (1.9.2) lib/omniauth/strategy.rb:192:in `call!' omniauth (1.9.2) lib/omniauth/strategy.rb:169:in `call' omniauth (1.9.2) lib/omniauth/strategy.rb:192:in `call!' omniauth (1.9.2) lib/omniauth/strategy.rb:169:in `call' omniauth (1.9.2) lib/omniauth/builder.rb:45:in `call' lib/middleware/omniauth_bypass_middleware.rb:53:in `call' rack (2.2.7) lib/rack/tempfile_reaper.rb:15:in `call' rack (2.2.7) lib/rack/conditional_get.rb:27:in `call' rack (2.2.7) lib/rack/head.rb:12:in `call' actionpack (7.0.4.3) lib/action_dispatch/http/permissions_policy.rb:38:in `call' lib/content_security_policy/middleware.rb:12:in `call' lib/middleware/anonymous_cache.rb:369:in `call' rack (2.2.7) lib/rack/session/abstract/id.rb:266:in `context' rack (2.2.7) lib/rack/session/abstract/id.rb:260:in `call' actionpack (7.0.4.3) lib/action_dispatch/middleware/cookies.rb:704:in `call' actionpack (7.0.4.3) lib/action_dispatch/middleware/callbacks.rb:27:in `block in call' activesupport (7.0.4.3) lib/active_support/callbacks.rb:99:in `run_callbacks' actionpack (7.0.4.3) lib/action_dispatch/middleware/callbacks.rb:26:in `call' actionpack (7.0.4.3) lib/action_dispatch/middleware/debug_exceptions.rb:28:in `call' actionpack (7.0.4.3) lib/action_dispatch/middleware/show_exceptions.rb:26:in `call' logster (2.12.2) lib/logster/middleware/reporter.rb:43:in `call' railties (7.0.4.3) lib/rails/rack/logger.rb:40:in `call_app' railties (7.0.4.3) lib/rails/rack/logger.rb:27:in `call' config/initializers/100-quiet_logger.rb:20:in `call' config/initializers/100-silence_logger.rb:29:in `call' actionpack (7.0.4.3) lib/action_dispatch/middleware/remote_ip.rb:93:in `call' actionpack (7.0.4.3) lib/action_dispatch/middleware/request_id.rb:26:in `call' lib/middleware/enforce_hostname.rb:24:in `call' rack (2.2.7) lib/rack/method_override.rb:24:in `call' actionpack (7.0.4.3) lib/action_dispatch/middleware/executor.rb:14:in `call' rack (2.2.7) lib/rack/sendfile.rb:110:in `call' actionpack (7.0.4.3) lib/action_dispatch/middleware/host_authorization.rb:131:in `call' rack-mini-profiler (3.1.0) lib/mini_profiler.rb:260:in `call' message_bus (4.3.2) lib/message_bus/rack/middleware.rb:60:in `call' lib/middleware/request_tracker.rb:228:in `call' railties (7.0.4.3) lib/rails/engine.rb:530:in `call' railties (7.0.4.3) lib/rails/railtie.rb:226:in `public_send' railties (7.0.4.3) lib/rails/railtie.rb:226:in `method_missing' rack (2.2.7) lib/rack/urlmap.rb:74:in `block in call' rack (2.2.7) lib/rack/urlmap.rb:58:in `each' rack (2.2.7) lib/rack/urlmap.rb:58:in `call' unicorn (6.1.0) lib/unicorn/http_server.rb:634:in `process_client' unicorn (6.1.0) lib/unicorn/http_server.rb:739:in `worker_loop' unicorn (6.1.0) lib/unicorn/http_server.rb:547:in `spawn_missing_workers' unicorn (6.1.0) lib/unicorn/http_server.rb:143:in `start' unicorn (6.1.0) bin/unicorn:128:in `' vendor/bundle/ruby/3.2.0/bin/unicorn:25:in `load' vendor/bundle/ruby/3.2.0/bin/unicorn:25:in `
' ``` Any hint is appreciated --- _[View the full topic](https://meta.discourse.org/t/error-while-trying-to-add-paytm-oauth-using-discourse-oauth2-basic-plugin/261407)._