1 files changed, 38 insertions, 0 deletions
diff --git a/app/models/clusters/concerns/elasticsearch_client.rb b/app/models/clusters/concerns/elasticsearch_client.rb
new file mode 100644
index 00000000000..7b0b6bdae02
--- /dev/null
+++ b/app/models/clusters/concerns/elasticsearch_client.rb
@@ -0,0 +1,38 @@
+# frozen_string_literal: true
+
+module Clusters
+  module Concerns
+    module ElasticsearchClient
+      include ::Gitlab::Utils::StrongMemoize
+
+      ELASTICSEARCH_PORT = 9200
+      ELASTICSEARCH_NAMESPACE = 'gitlab-managed-apps'
+
+      def elasticsearch_client(timeout: nil)
+        strong_memoize(:elasticsearch_client) do
+          kube_client = cluster&.kubeclient&.core_client
+          next unless kube_client
+
+          proxy_url = kube_client.proxy_url('service', service_name, ELASTICSEARCH_PORT, ELASTICSEARCH_NAMESPACE)
+
+          Elasticsearch::Client.new(url: proxy_url) do |faraday|
+            # ensures headers containing auth data are appended to original client options
+            faraday.headers.merge!(kube_client.headers)
+            # ensure TLS certs are properly verified
+            faraday.ssl[:verify] = kube_client.ssl_options[:verify_ssl]
+            faraday.ssl[:cert_store] = kube_client.ssl_options[:cert_store]
+            faraday.options.timeout = timeout unless timeout.nil?
+          end
+
+        rescue Kubeclient::HttpError => error
+          # If users have mistakenly set parameters or removed the depended clusters,
+          # `proxy_url` could raise an exception because gitlab can not communicate with the cluster.
+          # We check for a nil client in downstream use and behaviour is equivalent to an empty state
+          log_exception(error, :failed_to_create_elasticsearch_client)
+
+          nil
+        end
+      end
+    end
+  end
+end