feat: allow pacts to be published using the old API by setting the en…

…vironment variable PACT_BROKER_FEATURES=publish_pacts_using_old_api

lib/pact_broker/client/publish_pacts.rb

@@ -28,7 +28,7 @@ def initialize pact_broker_base_url, pact_file_paths, consumer_version_params, o
 
       def call
         validate
-        if index_resource.can?("pb:publish-contracts")
+        if !force_use_old_api? && index_resource.can?("pb:publish-contracts")
           publish_pacts
           PactBroker::Client::CommandResult.new(success?, message)
         else
@@ -40,6 +40,10 @@ def call
 
       attr_reader :pact_broker_base_url, :pact_file_paths, :consumer_version_params, :consumer_version_number, :branch, :tags, :build_url, :options, :pact_broker_client_options, :response_entities
 
+      def force_use_old_api?
+        ENV.fetch("PACT_BROKER_FEATURES", "").include?("publish_pacts_using_old_api")
+      end
+
       def request_body_for(consumer_name)
         {
           pacticipantName: consumer_name,