Merge pull request #8102 from apolcyn/failed_credentials_error_message

surface more exception info for call creds errors

src/ruby/ext/grpc/rb_call_credentials.c

@@ -86,19 +86,16 @@ static VALUE grpc_rb_call_credentials_callback_rescue(VALUE args,
       rb_funcall(exception_object, rb_intern("backtrace"), 0),
       rb_intern("join"),
       1, rb_str_new2("\n\tfrom "));
-  VALUE rb_exception_info = rb_funcall(exception_object, rb_intern("to_s"), 0);
-  const char *exception_classname = rb_obj_classname(exception_object);
+  VALUE rb_exception_info = rb_funcall(exception_object, rb_intern("inspect"), 0);
   (void)args;
-  gpr_log(GPR_INFO, "Call credentials callback failed: %s: %s\n%s",
-          exception_classname, StringValueCStr(rb_exception_info),
+  gpr_log(GPR_INFO, "Call credentials callback failed: %s\n%s",
+          StringValueCStr(rb_exception_info),
           StringValueCStr(backtrace));
   rb_hash_aset(result, rb_str_new2("metadata"), Qnil);
-  /* Currently only gives the exception class name. It should be possible get
-     more details */
   rb_hash_aset(result, rb_str_new2("status"),
-               INT2NUM(GRPC_STATUS_PERMISSION_DENIED));
+               INT2NUM(GRPC_STATUS_UNAUTHENTICATED));
   rb_hash_aset(result, rb_str_new2("details"),
-               rb_str_new2(exception_classname));
+               rb_exception_info);
   return result;
 }
 

src/ruby/spec/generic/client_stub_spec.rb

@@ -168,23 +168,61 @@ describe 'ClientStub' do
         expect(&blk).to raise_error(GRPC::BadStatus)
         th.join
       end
+
+      it 'should receive UNAUTHENTICATED if call credentials plugin fails' do
+        server_port = create_secure_test_server
+        th = run_request_response(@sent_msg, @resp, @pass)
+
+        certs = load_test_certs
+        secure_channel_creds = GRPC::Core::ChannelCredentials.new(
+          certs[0], nil, nil)
+        secure_stub_opts = {
+          channel_args: {
+            GRPC::Core::Channel::SSL_TARGET => 'foo.test.google.fr'
+          }
+        }
+        stub = GRPC::ClientStub.new("localhost:#{server_port}",
+                                    secure_channel_creds, **secure_stub_opts)
+
+        error_message = 'Failing call credentials callback'
+        failing_auth = proc do
+          fail error_message
+        end
+        creds = GRPC::Core::CallCredentials.new(failing_auth)
+
+        error_occured = false
+        begin
+          get_response(stub, credentials: creds)
+        rescue GRPC::BadStatus => e
+          error_occured = true
+          expect(e.code).to eq(GRPC::Core::StatusCodes::UNAUTHENTICATED)
+          expect(e.details.include?(error_message)).to be true
+        end
+        expect(error_occured).to eq(true)
+
+        # Kill the server thread so tests can complete
+        th.kill
+      end
     end
 
     describe 'without a call operation' do
-      def get_response(stub)
+      def get_response(stub, credentials: nil)
+        puts credentials.inspect
         stub.request_response(@method, @sent_msg, noop, noop,
-                              metadata: { k1: 'v1', k2: 'v2' })
+                              metadata: { k1: 'v1', k2: 'v2' },
+                              credentials: credentials)
       end
 
       it_behaves_like 'request response'
     end
 
     describe 'via a call operation' do
-      def get_response(stub)
+      def get_response(stub, credentials: nil)
         op = stub.request_response(@method, @sent_msg, noop, noop,
                                    return_op: true,
                                    metadata: { k1: 'v1', k2: 'v2' },
-                                   deadline: from_relative_time(2))
+                                   deadline: from_relative_time(2),
+                                   credentials: credentials)
         expect(op).to be_a(GRPC::ActiveCall::Operation)
         op.execute
       end
@@ -441,6 +479,15 @@ describe 'ClientStub' do
     end
   end
 
+  def create_secure_test_server
+    certs = load_test_certs
+    secure_credentials = GRPC::Core::ServerCredentials.new(
+      nil, [{ private_key: certs[1], cert_chain: certs[2] }], false)
+
+    @server = GRPC::Core::Server.new(nil)
+    @server.add_http2_port('0.0.0.0:0', secure_credentials)
+  end
+
   def create_test_server
     @server = GRPC::Core::Server.new(nil)
     @server.add_http2_port('0.0.0.0:0', :this_port_is_insecure)