Commit Graph

17 Commits

Author SHA1 Message Date
Daniel Nephin 20f7a72792 stream: remove bufferItem.NextLink
Both NextLink and NextNoBlock had the same logic, with slightly
different return values. By adding a bool return value (similar to map
lookups) we can remove the duplicate method.
2021-06-07 17:04:46 -04:00
Daniel Nephin a29b848e3b stream: fix a snapshot cache bug
Previously a snapshot created as part of a resumse-stream request could have incorrectly
cached the newSnapshotToFollow event. This would cause clients to error because they
received an unexpected framing event.
2021-02-16 12:52:23 -05:00
Daniel Nephin e4a78c977d stream: document that Payload must be immutable
If they are sent to EventPublisher.Publish.

Also document that PayloadEvents is expected to come from a subscription and that it is
not immutable.
2020-11-06 13:00:33 -05:00
Daniel Nephin b57c7afcbb stream: include the namespace in the snap cache key
Otherwise the wrong snapshot could be returned when the same key is used in different namespaces
2020-10-30 14:34:04 -04:00
Daniel Nephin 61ce0964a4 stream: remove Event.Key
Makes Payload a type with FilterByKey so that Payloads can implement
filtering by key. With this approach we don't need to expose a Namespace
field on Event, and we don't need to invest micro formats or require a
bunch of code to be aware of exactly how the key field is encoded.
2020-10-28 16:48:04 -04:00
Daniel Nephin f857aef4a8 submatview: add a test for handling of NewSnapshotToFollow
Also add some godoc
Rename some vars and functions
Fix a data race in the new cache test for entry closing.
2020-10-06 13:22:02 -04:00
Daniel Nephin 9c5181c897 stream: full test coverage for EventPublisher.Subscribe 2020-10-02 13:46:24 -04:00
Daniel Nephin 0769f54fe1 stream: refactor to support change in framing events
Removing EndOfEmptySnapshot, add NewSnapshotToFollow
2020-10-02 13:41:31 -04:00
Daniel Nephin d192b0a080 stream: move goroutine out of New
This change will make it easier to manage goroutine lifecycle from the caller.

Also expose EventPublisher from state.Store
2020-09-28 18:40:10 -04:00
Daniel Nephin 81cc3daf69 stream: have SnapshotFunc accept a non-pointer SubscribeRequest
The value is not expected to be modified. Passing a value makes that explicit.
2020-09-03 16:54:02 -04:00
Daniel Nephin decba06b7d stream: close all subs when EventProcessor is shutdown. 2020-07-22 19:04:10 -04:00
Daniel Nephin a2f8605c66 stream: Add forceClose and refactor subscription filtering
Move the subscription context to Next. context.Context should generally
never be stored in a struct because it makes that struct only valid
while the context is valid. This is rarely obvious from the caller.
Adds a forceClosed channel in place of the old context, and uses the new
context as a way for the caller to stop the Subscription blocking.

Remove some recursion out of bufferImte.Next. The caller is already looping so we can continue
in that loop instead of recursing. This ensures currentItem is updated immediately (which probably
does not matter in practice), and also removes the chance that we overflow the stack.

NextNoBlock and FollowAfter do not need to handle bufferItem.Err, the caller already
handles it.

Moves filter to a method to simplify Next, and more explicitly separate filtering from looping.

Also improve some godoc

Only unwrap itemBuffer.Err when necessary
2020-07-14 15:57:47 -04:00
Daniel Nephin 2595436f62 stream: Improve docstrings
Also rename ResumeStrema to EndOfEmptySnapshot to be more consistent with other framing events

Co-authored-by: Paul Banks <banks@banksco.de>
2020-07-14 15:57:47 -04:00
Daniel Nephin 16a2b3fafc stream: change Topic to an interface
Consumers of the package can decide on which type to use for the Topic. In the future we may
use a gRPC type for the topic.
2020-07-14 15:57:47 -04:00
Daniel Nephin aa571bd0ce state: Move change processing out of EventPublisher
EventPublisher was receiving TopicHandlers, which had a couple of
problems:

- ChangeProcessors were being grouped by Topic, but they completely
  ignored the topic and were performed on every change
- ChangeProcessors required EventPublisher to be aware of database
  changes

By moving ChangeProcesors out of EventPublisher, and having Publish
accept events instead of changes, EventPublisher no longer needs to
be aware of these things.

Handlers is now only SnapshotHandlers, which are still mapped by Topic.

Also allows us to remove the small 'db' package that had only two types.
They can now be unexported types in state.
2020-07-14 15:57:47 -04:00
Daniel Nephin e1305fe80c stream: unexport identifiers
Now that EventPublisher is part of stream a lot of the internals can be hidden
2020-07-14 15:57:47 -04:00
Daniel Nephin 9e37894778 stream: Move EventPublisher to stream package
The EventPublisher is the central hub of the PubSub system. It is toughly coupled with much of
stream. Some stream internals were exported exclusively for EventPublisher.

The two Subscribe cases (with or without index) were also awkwardly split between two packages. By
moving EventPublisher into stream they are now both in the same package (although still in different files).
2020-07-14 15:57:47 -04:00
Renamed from agent/consul/state/event_publisher.go (Browse further)