Implements a PubSub HTTP server that manages a collection of in-memory WebSocket clients that subscribe, and a publish endpoint that will deliver a message to all subscribed HTTP WebSocket clients.
TestPubSub is an integration test that will start a PubSub server and spawn concurrent subscribers and publishers to ensure the expected number of messages are received.
$ go test -race -v -count 1 .
...
[PUBSUB SERVER]: 2020/03/19 01:08:21 publish to [count=50] subscribers: [Publisher: 24] Message [4]
...
[PUBSUB CLIENT: 127.0.0.1:49333]: 2020/03/19 01:08:21 client received message: [Publisher: 48] Message [4]
--- PASS: TestPubSub (1.41s)
PASS
ok github.com/dougnukem/pubsub 1.554s
Commands can be run directly from checked out repo, or via:
$ go get github.com/dougnukem/pubsub
# Assuming $GOPATH/bin is in your $PATH
$ pubsub server -help
Usage of server:
-addr string
pubsub server address to listen on (default ":8080")
server - starts an HTTP server that listens for WebSocket clients to subscribe and messages to be published
$ pubsub server -addr=":8080"
[PUBSUB SERVER]: 2020/03/19 01:36:03 listening on: :8080
[PUBSUB SERVER]: 2020/03/19 01:36:10 new subscriber [count=1]: 127.0.0.1:55127
[PUBSUB SERVER]: 2020/03/19 01:36:18 publish to [count=1] subscribers: Hello there
[PUBSUB SERVER]: 2020/03/19 01:37:55 new subscriber [count=2]: 127.0.0.1:55218
Endpoints:
/subscribe- WebSocket endpoint for a client to subscribe and be delivered published messages/publish- HTTP POST endpoint for messages to be published and sent to all subscribed WebSocket clients
$ pubsub client
[PUBSUB CLIENT: 127.0.0.1:55127]: 2020/03/19 01:36:10 subscribed waiting for published messages
[PUBSUB CLIENT: 127.0.0.1:55127]: 2020/03/19 01:36:18 client received message: Hello there
$ pubsub publish -message="Hello there"
[PUBSUB PUBLISHER]: 2020/03/19 01:39:14 Published message[Hello there] to [:8080]