Allow setting credentials as lambda

lib/temporal/configuration.rb

@@ -15,7 +15,8 @@ class Configuration
     Execution = Struct.new(:namespace, :task_queue, :timeouts, :headers, :search_attributes, keyword_init: true)
 
     attr_reader :timeouts, :error_handlers
-    attr_accessor :connection_type, :converter, :use_error_serialization_v2, :host, :port, :credentials, :identity,
+    attr_writer :credentials
+    attr_accessor :connection_type, :converter, :use_error_serialization_v2, :host, :port, :identity,
                   :logger, :metrics_adapter, :namespace, :task_queue, :headers, :search_attributes, :header_propagators,
                   :payload_codec
 
@@ -100,6 +101,12 @@ def timeouts=(new_timeouts)
       @timeouts = DEFAULT_TIMEOUTS.merge(new_timeouts)
     end
 
+    def credentials
+      return @credentials.call if @credentials.is_a?(Proc)
+
+      @credentials
+    end
+
     def for_connection
       Connection.new(
         type: connection_type,

spec/unit/lib/temporal/configuration_spec.rb

@@ -61,5 +61,19 @@ def inject!(_); end
       subject.identity = new_identity
       expect(subject.for_connection).to have_attributes(identity: new_identity)
     end
+
+    it 'default credentials' do
+      expect(subject.for_connection).to have_attributes(credentials: :this_channel_is_insecure)
+    end
+
+    it 'override credentials' do
+      subject.credentials = :test_credentials
+      expect(subject.for_connection).to have_attributes(credentials: :test_credentials)
+    end
+
+    it 'override credentials with lambda' do
+      subject.credentials = -> { :test_credentials }
+      expect(subject.for_connection).to have_attributes(credentials: :test_credentials)
+    end
   end
-end
+end