Simple multi-thread Pub Sub server in Rust.
I wanted to learn how to use Polling from smol with a thread pool.
To subscribe, send a message starting with +, the first word after + will be used as the channel to be subscribed.
$ +somechannel
If you send more words, those will be considered a first message.
$ +somechannel Subscribed and a first message!
To send a message without subscribing, use :
$ :somechannel Some message to all somechannel subscribers.
To unsubscribe use -
$ -somechannel
It's also possible to send a last message while unsubscribing:
$ -somechannel And a last message.
When you are subscribed to a channel, you also receive the key in the first word of the message. This way clients can react properly.
$ somechannel Some message to this channel.
With Rust installed, just run:
cargo run
In unix consoles you can connect with nc as client:
$ nc 127.0.0.1 1984
But any TcpStream stream from your favorite language will do.
I learned a lot, but the architecture is flawed.
If you want this same API without problems check out the improved atomsub.
Right now, reading and writing is handled independently, so you can read and write at the same time safely. But It turns out that while the thread pool has the connection queued, that connection can't be used for the same operation until that job is done. So, on super fast events (milliseconds) you can loose information.
Like trying to write super fast twice in a row, or reading twice super fast from a client.