dart-sdk/pkg/dds
Danny Tuppeny 7a6352a9b1 [dds/dap] Ensure DAP always responds to initialize() before sending initializedEvent
Changes to support DAP in DDS introduced a subtle bug where we could send the `InitializedEvent` before the response to the `Initialize` request because `sendResponse` used a `Completer` and would delay adding the response to the stream until the next iteration of the task queue.

Although there were comments stating this order must be preserved, there were no tests that verified this and it breaks VS Code (https://github.com/dart-lang/sdk/issues/52222).

I've added tests for this, and changed how this works slightly so instead of using a `Completer` we pass in a "responseWriter" function that must write the response to the stream synchronously.

Since the DDS path isn't using events yet and it would require a little more refactoring, I've used a Completer there and added a TODO.

Fixes https://github.com/dart-lang/sdk/issues/52222.

Change-Id: I1832126f5015b466c721dbda192da4b8a5d83b62
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/300601
Reviewed-by: Ben Konyi <bkonyi@google.com>
Commit-Queue: Ben Konyi <bkonyi@google.com>
2023-05-02 18:35:26 +00:00
..
bin Reland "[ Service / DDS ] Remove VM service polling logic, add --enable-service-fallback-port support to DDS" 2022-03-15 18:14:42 +00:00
example Reland "[ package:dds ] Add null safety support" 2021-05-24 16:59:23 +00:00
lib [dds/dap] Ensure DAP always responds to initialize() before sending initializedEvent 2023-05-02 18:35:26 +00:00
test [dds/dap] Ensure DAP always responds to initialize() before sending initializedEvent 2023-05-02 18:35:26 +00:00
tool [pkg/dds] use package:lints/recommended.yaml 2023-02-21 18:30:23 +00:00
.gitignore
analysis_options.yaml [pkg/dds] use package:lints/recommended.yaml 2023-02-21 18:30:23 +00:00
CHANGELOG.md [dds/dap] Don't throw if isolates exit while trying to resume them 2023-05-01 14:43:51 +00:00
dds_protocol.md [dds/dap] Forward toolEvents on to the DAP client 2023-01-13 17:49:12 +00:00
LICENSE Update LICENSE 2021-04-07 10:28:38 +00:00
OWNERS [infra] Add OWNERS to the Dart SDK 2022-02-14 14:06:34 +00:00
pubspec.yaml [dds/dap] Don't throw if isolates exit while trying to resume them 2023-05-01 14:43:51 +00:00
README.md Fix typos 2022-07-12 19:35:22 +00:00

pub package package publisher

A package used to spawn the Dart Developer Service (DDS), which is used to communicate with a Dart VM Service instance and provide extended functionality to the core VM Service Protocol.

Functionality

Existing VM Service clients can issue both HTTP, websocket, and SSE requests to a running DDS instance as if it were an instance of the VM Service itself. If a request corresponds to an RPC defined in the VM Service Protocol, DDS will forward the request and return the response from the VM Service. Requests corresponding to an RPC defined in the DDS Protocol will be handled directly by the DDS instance.

SSE Support

For certain web clients it may be preferable or required to communicate with DDS using server-sent events (SSE). DDS has an SSE handler listening for requests on /$debugHandler.

SSE and package:vm_service example

import 'package:sse/sse.dart';
import 'package:vm_service/vm_service.dart';

void main() {
  // Establish connection with DDS using SSE.
  final ddsChannel = SseClient('${ddsUri}\$debugHandler');

  // Wait for ddsChannel to be established
  await ddsChannel.onOpen.first;

  // Initialize VmService using the sink and stream from ddsChannel.
  final vmService = VmService(
    ddsChannel.stream,
    (e) => ddsChannel.sink.add(e),
  );

  // You're ready to query DDS and the VM service!
  print(await vmService.getVersion());
}