Commit Graph

8 Commits

Author SHA1 Message Date
Daniel Nephin e802689bbe stream: fix overallocation in filter
And add tests
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 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 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 c778d61b6a stream.Subscription unexport fields and additiona docstrings 2020-07-14 15:57:46 -04:00
Daniel Nephin 02bc5a26e4 EventPublisher: Make Unsubscribe a function on Subscription
It is critical that Unsubscribe be called with the same pointer to a
SubscriptionRequest that was used to create the Subscription. The
docstring made that clear, but it sill allowed a caler to get it wrong by
creating a new SubscriptionRequest.

By hiding this detail from the caller, and only exposing an Unsubscribe
method, it should be impossible to fail to Unsubscribe.

Also update some godoc strings.
2020-07-14 15:57:46 -04:00
Daniel Nephin 2e45bbbb3e stream: Use local types for Event Topic SubscriptionRequest 2020-07-14 15:57:45 -04:00
Daniel Nephin 526fb53f85 Add streaming package with Subscription and Snapshot components.
The remaining files from 7965767de0bd62ab07669b85d6879bd5f815d157

Co-authored-by: Paul Banks <banks@banksco.de>
2020-07-14 15:57:44 -04:00