Support query parameters in metrics embeds

https://gitlab.com/gitlab-org/gitlab-ce/issues/62971

Adds support for embedding specific charts from the
metrics dashboard. Expected parameters are dashboard,
title, group, and y_label.

2 files changed, 36 insertions, 13 deletions

diff --git a/lib/banzai/filter/inline_metrics_filter.rb b/lib/banzai/filter/inline_metrics_filter.rb
index 0120cc37d6f..c5a328c21b2 100644
--- a/lib/banzai/filter/inline_metrics_filter.rb
+++ b/lib/banzai/filter/inline_metrics_filter.rb
@@ -15,17 +15,6 @@ module Banzai
         )
       end
 
-      # Endpoint FE should hit to collect the appropriate
-      # chart information
-      def metrics_dashboard_url(params)
-        Gitlab::Metrics::Dashboard::Url.build_dashboard_url(
-          params['namespace'],
-          params['project'],
-          params['environment'],
-          embedded: true
-        )
-      end
-
       # Search params for selecting metrics links. A few
       # simple checks is enough to boost performance without
       # the cost of doing a full regex match.
@@ -38,6 +27,28 @@ module Banzai
       def link_pattern
         Gitlab::Metrics::Dashboard::Url.regex
       end
+
+      private
+
+      # Endpoint FE should hit to collect the appropriate
+      # chart information
+      def metrics_dashboard_url(params)
+        Gitlab::Metrics::Dashboard::Url.build_dashboard_url(
+          params['namespace'],
+          params['project'],
+          params['environment'],
+          embedded: true,
+          **query_params(params['url'])
+        )
+      end
+
+      # Parses query params out from full url string into hash.
+      #
+      # Ex) 'https://<root>/<project>/<environment>/metrics?title=Title&group=Group'
+      #       --> { title: 'Title', group: 'Group' }
+      def query_params(url)
+        Gitlab::Metrics::Dashboard::Url.parse_query(url)
+      end
     end
   end
 end
diff --git a/lib/gitlab/metrics/dashboard/url.rb b/lib/gitlab/metrics/dashboard/url.rb
index b197e7ca86b..94f8b2e02b1 100644
--- a/lib/gitlab/metrics/dashboard/url.rb
+++ b/lib/gitlab/metrics/dashboard/url.rb
@@ -21,14 +21,26 @@ module Gitlab
                 \/(?<environment>\d+)
                 \/metrics
                 (?<query>
-                  \?[a-z0-9_=-]+
-                  (&[a-z0-9_=-]+)*
+                  \?[a-zA-Z0-9%.()+_=-]+
+                  (&[a-zA-Z0-9%.()+_=-]+)*
                 )?
                 (?<anchor>\#[a-z0-9_-]+)?
               )
             }x
           end
 
+          # Parses query params out from full url string into hash.
+          #
+          # Ex) 'https://<root>/<project>/<environment>/metrics?title=Title&group=Group'
+          #       --> { title: 'Title', group: 'Group' }
+          def parse_query(url)
+            query_string = URI.parse(url).query.to_s
+
+            CGI.parse(query_string)
+              .transform_values { |value| value.first }
+              .symbolize_keys
+          end
+
           # Builds a metrics dashboard url based on the passed in arguments
           def build_dashboard_url(*args)
             Gitlab::Routing.url_helpers.metrics_dashboard_namespace_project_environment_url(*args)