devtools: Add support for one-way protocol messages#43230
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Signed-off-by: Brent Schroeter <contact@brentsch.com>
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Example of a one-way message type in the Firefox spec, for reference: https://github.com/mozilla-firefox/firefox/blob/a86d8293217bbdc69abd541c9c7f8a4c6e227a8c/devtools/shared/specs/watcher.js#L28 |
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@eerii Another small stepping stone on the way to fixing navigation for the devtools inspector panel. |
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Great! This gets rid of some of the warnings when closing DevTools.
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| /// Like `reply`, but it doesn't check if it is a valid reply. | ||
| /// Sometimes the client breaks the rules and expects an out of form message. | ||
| pub fn reply_unchecked<T: Serialize>( |
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I'll make a followup to remove reply_unchecked, as it no longer needs to be separate from reply. We can use write_json_packet followed by mark_handled. As far as I can tell this is only used in frame::getEnvironment.
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`reply_unchecked` was added in #42007 since `getEnvironment` from the frame actor has a `type` field but it already counts as a final reply, unlike every other message like it. Since it is only used there, we can revert the `reply_unchecked` change and use the new `mark_handled` instead. Depends on: #43230 Testing: DevTools tests Signed-off-by: eri <eri@igalia.com>
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Some Remote Debugging Protocol message types are specified as `oneway`, meaning that they expect no reply. Sending anything—including an error—in response to these messages throws the devtools client and actor out of sync. As noted in the `ClientRequest` docstring, most client messages expect exactly one reply, so `ClientRequest::handle()` includes a fail-safe that automatically sends an error message if none of the `reply()`, `reply_unchecked()`, or `reply_final()` methods have been called. This change introduces an additional method, `ClientRequest::mark_handled()`, which allows the actor handling the request to disarm the fail-safe without sending a reply over the wire, and it adds handling logic for 3 one-way message types that are frequently emitted by the Firefox Toolbox. Testing: This change introduces no new tests. Unless we take the unusual step of enumerating all supported one-way message types and validating each, automated tests provide little assurance of correctness. Meaningfully testing this feature would be cumbersome, and it would likely hamper future development more than it would help. Signed-off-by: Brent Schroeter <contact@brentsch.com> (cherry picked from commit 69a1f99)
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…#43236) `reply_unchecked` was added in servo#42007 since `getEnvironment` from the frame actor has a `type` field but it already counts as a final reply, unlike every other message like it. Since it is only used there, we can revert the `reply_unchecked` change and use the new `mark_handled` instead. Depends on: servo#43230 Testing: DevTools tests Signed-off-by: eri <eri@igalia.com> (cherry picked from commit 5c30339)
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Some Remote Debugging Protocol message types are specified as
oneway, meaning that they expect no reply. Sending anything—including an error—in response to these messages throws the devtools client and actor out of sync.As noted in the
ClientRequestdocstring, most client messages expect exactly one reply, soClientRequest::handle()includes a fail-safe that automatically sends an error message if none of thereply(),reply_unchecked(), orreply_final()methods have been called.This change introduces an additional method,
ClientRequest::mark_handled(), which allows the actor handling the request to disarm the fail-safe without sending a reply over the wire, and it adds handling logic for 3 one-way message types that are frequently emitted by the Firefox Toolbox.Testing: This change introduces no new tests. Unless we take the unusual step of enumerating all supported one-way message types and validating each, automated tests provide little assurance of correctness. Meaningfully testing this feature would be cumbersome, and it would likely hamper future development more than it would help.