commit 6de68d541ab3c5ccdda58539266283b2077461fc
author Ben Konyi <bkonyi@google.com> Sun Jan 17 23:08:18 2021 +0000
committer commit-bot@chromium.org <commit-bot@chromium.org> Sun Jan 17 23:08:18 2021 +0000
tree e745476f2d4c304f5273d3627ec82d6f978a9879
parent 5e66c2b1a1efa890aef04f7c583ee74cc68f9c51

[ package:dds ] Fix issue where handling a StateError due to a VM
service connection loss could result in a null JSON RPC response.

This would cause package:vm_service to throw a NoSuchMethodError as it
currently assumes it will never receive a null result in a JSON RPC
response.

Related to https://github.com/flutter/flutter/issues/74051.

Change-Id: I86c1c9f7e46e34519f32dfed589c6b31aed39d7f
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/179800
Reviewed-by: Zach Anderson <zra@google.com>
Commit-Queue: Ben Konyi <bkonyi@google.com>

pkg/dds/CHANGELOG.md

diff --git a/pkg/dds/CHANGELOG.md b/pkg/dds/CHANGELOG.md
index 80420e2..13e8fca 100644
--- a/pkg/dds/CHANGELOG.md
+++ b/pkg/dds/CHANGELOG.md
@@ -1,3 +1,7 @@
+# 1.7.2
+- Fixed issue where a null JSON RPC result could be sent if the VM service
+  disconnected with a request in flight (see https://github.com/flutter/flutter/issues/74051).
+
 # 1.7.1
 - Fixed issue where DartDevelopmentServiceException could have a null message.
 

pkg/dds/lib/src/client.dart

diff --git a/pkg/dds/lib/src/client.dart b/pkg/dds/lib/src/client.dart
index f8018f9..7b64867 100644
--- a/pkg/dds/lib/src/client.dart
+++ b/pkg/dds/lib/src/client.dart
@@ -266,12 +266,14 @@
     // Unless otherwise specified, the request is forwarded to the VM service.
     // NOTE: This must be the last fallback registered.
     _clientPeer.registerFallback((parameters) async {
-      try {
-        return await _vmServicePeer.sendRequest(
-            parameters.method, parameters.value);
-      } on StateError {
-        await dds.shutdown();
-      }
+      // If _vmServicePeer closes in the middle of a request, this will throw
+      // a StateError that will be forwarded to the requesting client.
+      // Listeners in dds_impl.dart will handle shutting down the DDS, so
+      // we don't try and handle the error here.
+      return await _vmServicePeer.sendRequest(
+        parameters.method,
+        parameters.value,
+      );
     });
   }
 

pkg/dds/pubspec.yaml

diff --git a/pkg/dds/pubspec.yaml b/pkg/dds/pubspec.yaml
index a7fff90..6e69aa5 100644
--- a/pkg/dds/pubspec.yaml
+++ b/pkg/dds/pubspec.yaml
@@ -3,7 +3,7 @@
   A library used to spawn the Dart Developer Service, used to communicate with
   a Dart VM Service instance.
 
-version: 1.7.1
+version: 1.7.2
 
 homepage: https://github.com/dart-lang/sdk/tree/master/pkg/dds
 

pkg/dds/test/handles_client_disconnect_state_error_test.dart

diff --git a/pkg/dds/test/handles_client_disconnect_state_error_test.dart b/pkg/dds/test/handles_client_disconnect_state_error_test.dart
index 0b93db4..7499a52 100644
--- a/pkg/dds/test/handles_client_disconnect_state_error_test.dart
+++ b/pkg/dds/test/handles_client_disconnect_state_error_test.dart
@@ -29,6 +29,9 @@
         completer.completeError(
           StateError('The client closed with pending request "foo".'),
         );
+        doneCompleter.completeError(
+          StateError('The client closed with pending request "foo".'),
+        );
         break;
       default:
         completer.complete(await super.sendRequest(method, args));
@@ -83,8 +86,8 @@
     // unexpectedly.
     try {
       await client.sendRequest('foo');
-    } on StateError {
-      // This state error is expected. This test is ensuring that DDS exits
+    } on json_rpc.RpcException {
+      // This RPC exception is expected. This test is ensuring that DDS exits
       // gracefully even if the VM service disappears.
     }