Merge branch 'qa-112-prefer-env-credentials-for-gcloud' into 'master'

Auto DevOps QA: Prefer gcloud credentials from env

See merge request gitlab-org/gitlab-ce!20338

qa/qa/runtime/env.rb

@@ -62,6 +62,10 @@ module QA
       def gcloud_zone
         ENV.fetch('GCLOUD_ZONE')
       end
+
+      def has_gcloud_credentials?
+        %w[GCLOUD_ACCOUNT_KEY GCLOUD_ACCOUNT_EMAIL].none? { |var| ENV[var].to_s.empty? }
+      end
     end
   end
 end

qa/qa/service/kubernetes_cluster.rb

@@ -50,11 +50,15 @@ module QA
       end
 
       def login_if_not_already_logged_in
-        account = `gcloud auth list --filter=status:ACTIVE --format="value(account)"`
-        if account.empty?
+        if Runtime::Env.has_gcloud_credentials?
           attempt_login_with_env_vars
         else
-          puts "gcloud account found. Using: #{account} for creating K8s cluster."
+          account = `gcloud auth list --filter=status:ACTIVE --format="value(account)"`
+          if account.empty?
+            raise "Failed to login to gcloud. No credentials provided in environment and no credentials found locally."
+          else
+            puts "gcloud account found. Using: #{account} for creating K8s cluster."
+          end
         end
       end