[Web runtime] Add HTTP SSE action support

[minggangw]

No description provided.

[Copilot]

🟡 Changes recommended

Several unresolved HTTP action correctness, reliability, and discoverability issues remain.

Once you've addressed the issues Copilot identified, you can request another Copilot review.

Pull request overview

Adds HTTP Server-Sent Events support for action goals, including routing, client handling, tests, documentation, and CLI capability reporting.

Changes:

• Adds HTTP action SSE streaming for feedback and results.
• Updates the web client and TypeScript declarations.
• Adds integration coverage and CLI support reporting.

File summaries

File	Findings
web/index.d.ts	No findings.
web/client.js	Moderate: generate unique action handle IDs and reject undefined terminal results. Nit: update outdated HTTP action transport documentation.
test/test-web-action.js	No findings.
lib/runtime/transports/http.js	Moderate: map unavailable actions to 503, buffer feedback before acceptance, and add action-stream heartbeats. Nit: include action routes in the OpenAPI document.
bin/rclnodejs-web.js	No findings.

Review details

Suppressed comments (3)

lib/runtime/transports/http.js:36

• The dispatcher emits code: 'action_unavailable' when an exposed action server is unavailable, but this new mapping omits it, so HttpActionConnection falls through to HTTP 500. Map this backend-unavailable case to 503 so HTTP clients can distinguish it from an internal action failure.

  goal_rejected: 409,
  action_failed: 500,
  unknown_goal_id: 400,

lib/runtime/transports/http.js:425

• feedback can arrive before _handleActionGoalResponse() sends the {ok:true} acknowledgement—the WebSocket client explicitly registers goals before sending to handle this race. This path writes that feedback immediately, so the HTTP stream can violate the documented accepted → feedback order and clients waiting for accepted can miss it; buffer feedback until the acceptance frame is emitted.

    // Feedback delivery — zero or more, only while streaming.
    if (frame.event === 'feedback') {
      this._ensureStream();
      this._writeEvent('feedback', frame.payload);

lib/runtime/transports/http.js:468

• Unlike HttpSseConnection, this action stream has no heartbeat after the accepted event. A long-running goal that emits no feedback can therefore be closed by an idle proxy or client, causing _pumpActionStream to reject with connection_lost while the server continues the goal (HTTP disconnects do not cancel it). Reuse the configured SSE keep-alive behavior for action streams or provide an equivalent action heartbeat.

    this.res.writeHead(200, {
      'content-type': 'text/event-stream; charset=utf-8',
      'cache-control': 'no-cache, no-transform',
      connection: 'keep-alive',
      'x-accel-buffering': 'no',

• Files reviewed: 3/5 changed files
• Comments generated: 4
• Review effort level: Lite

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[coveralls]

coverage: 90.994% (+0.07%) from 90.924% — minggangw:fix-1579-http-sse into RobotWebTools:develop

[Copilot]

🟡 Changes recommended

In-flight client streams cannot be closed, and server streams lack configured heartbeats.

Once you've addressed the issues Copilot identified, you can request another Copilot review.

Review details

• Files reviewed: 5/7 changed files
• Comments generated: 2
• Review effort level: Balanced