Add Prometheus metrics to track reCAPTCHA success/failuressh-add-captcha-prometheus-counters

2 files changed, 32 insertions, 1 deletions

diff --git a/app/controllers/sessions_controller.rb b/app/controllers/sessions_controller.rb
index 7aa277b3614..f8483221965 100644
--- a/app/controllers/sessions_controller.rb
+++ b/app/controllers/sessions_controller.rb
@@ -62,7 +62,11 @@ class SessionsController < Devise::SessionsController
     return unless captcha_enabled?
     return unless Gitlab::Recaptcha.load_configurations!
 
-    unless verify_recaptcha
+    if verify_recaptcha
+      increment_successful_login_captcha_counter
+    else
+      increment_failed_login_captcha_counter
+
       self.resource = resource_class.new
       flash[:alert] = 'There was an error with the reCAPTCHA. Please solve the reCAPTCHA again.'
       flash.delete :recaptcha_error
@@ -71,6 +75,20 @@ class SessionsController < Devise::SessionsController
     end
   end
 
+  def increment_failed_login_captcha_counter
+    Gitlab::Metrics.counter(
+      :failed_login_captcha_total,
+      'Number of failed CAPTCHA attempts for logins'
+    ).increment
+  end
+
+  def increment_successful_login_captcha_counter
+    Gitlab::Metrics.counter(
+      :successful_login_captcha_total,
+      'Number of successful CAPTCHA attempts for logins'
+    ).increment
+  end
+
   def log_failed_login
     Gitlab::AppLogger.info("Failed Login: username=#{user_params[:login]} ip=#{request.remote_ip}")
   end
diff --git a/spec/controllers/sessions_controller_spec.rb b/spec/controllers/sessions_controller_spec.rb
index cdec26bd421..aa2f6c0f6f6 100644
--- a/spec/controllers/sessions_controller_spec.rb
+++ b/spec/controllers/sessions_controller_spec.rb
@@ -93,6 +93,12 @@ describe SessionsController do
         it 'displays an error when the reCAPTCHA is not solved' do
           # Without this, `verify_recaptcha` arbitraily returns true in test env
           Recaptcha.configuration.skip_verify_env.delete('test')
+          counter = double(:counter)
+
+          expect(counter).to receive(:increment)
+          expect(Gitlab::Metrics).to receive(:counter)
+                                      .with(:failed_login_captcha_total,
+                                            'Number of failed CAPTCHA attempts for logins').and_return(counter)
 
           post(:create, user: user_params)
 
@@ -104,6 +110,13 @@ describe SessionsController do
         it 'successfully logs in a user when reCAPTCHA is solved' do
           # Avoid test ordering issue and ensure `verify_recaptcha` returns true
           Recaptcha.configuration.skip_verify_env << 'test'
+          counter = double(:counter)
+
+          expect(counter).to receive(:increment)
+          expect(Gitlab::Metrics).to receive(:counter)
+                                      .with(:successful_login_captcha_total,
+                                            'Number of successful CAPTCHA attempts for logins').and_return(counter)
+          expect(Gitlab::Metrics).to receive(:counter).and_call_original
 
           post(:create, user: user_params)