submap

B-tree map for pub/sub services.

Create a new subscription map

let mut smap: SubMap<Client> = SubMap::new();

where "Client" is a pub/sub client type, which is usually either a channel or a structure which contains a channel or locked socket or anything else, required to work with the client.

The client type MUST provide traits Hash, Eq and Clone.

Separators and wildcards

SubMap supports the following masks:

• this/is/a/topic - single topic subscription
• this/?/a/topic - all topics which match the pattern (2nd chunk - any value)
• this/is/* - all subtopics of "this/is"
• * - all topics

Service symbols can be changed. E.g. let us create a subscription map with MQTT-style wildcards (+ for ? and # for *) but with the dot as the subtopic separator:

let mut smap: SubMap<Client> =
    SubMap::new().separator('.').match_any("+").wildcard("#");

Note that "/topic/x", "topic/x" and "topic//x" are 3 different topics. If any kind of normalization is required, it should be done manually, before calling SubMap functions.

Usage

All clients must be registered in the map, before they can subscribe/unsubscribe. Use "register_client" function for this.

When "unregister_client" is called, it also automatically unsubscribes the client from all the subscribed topics.

Cargo crate

https://crates.io/crates/submap