mirror of
https://github.com/vector-im/element-web.git
synced 2024-11-24 17:38:40 +08:00
c05c429803
Co-authored-by: github-merge-queue <118344674+github-merge-queue@users.noreply.github.com> Co-authored-by: github-merge-queue <github-merge-queue@users.noreply.github.com> Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com> Co-authored-by: Florian Duros <florian.duros@ormaz.fr> Co-authored-by: Kim Brose <kim.brose@nordeck.net> Co-authored-by: Florian Duros <florianduros@element.io> Co-authored-by: R Midhun Suresh <hi@midhun.dev> Co-authored-by: dbkr <986903+dbkr@users.noreply.github.com> Co-authored-by: ElementRobot <releases@riot.im> Co-authored-by: dbkr <dbkr@users.noreply.github.com> Co-authored-by: David Baker <dbkr@users.noreply.github.com> Co-authored-by: Michael Telatynski <7t3chguy@gmail.com> Co-authored-by: Richard van der Hoff <1389908+richvdh@users.noreply.github.com> Co-authored-by: David Langley <davidl@element.io> Co-authored-by: Michael Weimann <michaelw@matrix.org> Co-authored-by: Timshel <Timshel@users.noreply.github.com> Co-authored-by: Sahil Silare <32628578+sahil9001@users.noreply.github.com> Co-authored-by: Will Hunt <will@half-shot.uk> Co-authored-by: Hubert Chathi <hubert@uhoreg.ca> Co-authored-by: Andrew Ferrazzutti <andrewf@element.io> Co-authored-by: Robin <robin@robin.town> Co-authored-by: Tulir Asokan <tulir@maunium.net>
39 lines
2.1 KiB
Markdown
39 lines
2.1 KiB
Markdown
# Local echo (developer docs)
|
|
|
|
The React SDK provides some local echo functionality to allow for components to do something
|
|
quickly and fall back when it fails. This is all available in the `local-echo` directory within
|
|
`stores`.
|
|
|
|
Echo is handled in EchoChambers, with `GenericEchoChamber` being the base implementation for all
|
|
chambers. The `EchoChamber` class is provided as semantic access to a `GenericEchoChamber`
|
|
implementation, such as the `RoomEchoChamber` (which handles echoable details of a room).
|
|
|
|
Anything that can be locally echoed will be provided by the `GenericEchoChamber` implementation.
|
|
The echo chamber will also need to deal with external changes, and has full control over whether
|
|
or not something has successfully been echoed.
|
|
|
|
An `EchoContext` is provided to echo chambers (usually with a matching type: `RoomEchoContext`
|
|
gets provided to a `RoomEchoChamber` for example) with details about their intended area of
|
|
effect, as well as manage `EchoTransaction`s. An `EchoTransaction` is simply a unit of work that
|
|
needs to be locally echoed.
|
|
|
|
The `EchoStore` manages echo chamber instances, builds contexts, and is generally less semantically
|
|
accessible than the `EchoChamber` class. For separation of concerns, and to try and keep things
|
|
tidy, this is an intentional design decision.
|
|
|
|
**Note**: The local echo stack uses a "whenable" pattern, which is similar to thenables and
|
|
`EventEmitter`. Whenables are ways of actioning a changing condition without having to deal
|
|
with listeners being torn down. Once the reference count of the Whenable causes garbage collection,
|
|
the Whenable's listeners will also be torn down. This is accelerated by the `IDestroyable` interface
|
|
usage.
|
|
|
|
## Audit functionality
|
|
|
|
The UI supports a "Server isn't responding" dialog which includes a partial audit log-like
|
|
structure to it. This is partially the reason for added complexity of `EchoTransaction`s
|
|
and `EchoContext`s - this information feeds the UI states which then provide direct retry
|
|
mechanisms.
|
|
|
|
The `EchoStore` is responsible for ensuring that the appropriate non-urgent toast (lower left)
|
|
is set up, where the dialog then drives through the contexts and transactions.
|