twilight-cache-inmemory

twilight-cache-inmemory is an in-process-memory cache for the twilight-rs ecosystem. It's responsible for processing events and caching things like guilds, channels, users, and voice states.

Statistics

Statistics can be an important debugging tool for determining how large a cache is or determining whether a cache has an expected amount of resources within it. An interface for retrieving statistics about the amount of a resource within the cache as a whole or on a guild-level can be retrieved via InMemoryCache::stats.

Features

By default no feature is enabled.

permission-calculator

The permission-calculator feature flag will bring in support for the PermissionCalculator; an API for calculating permissions through it is exposed via InMemoryCache::permissions. Support for calculating the permissions of a member on a root guild-level and in a guild channel is included.

Refer to the permission module for more documentation.

Examples

Update a cache with events that come in through the gateway:

use std::{env, error::Error};
use twilight_cache_inmemory::DefaultInMemoryCache;
use twilight_gateway::{EventTypeFlags, Intents, Shard, ShardId, StreamExt as _};

#[tokio::main]
async fn main() -> Result<(), Box<dyn Error>> {
    // Initialize the tracing subscriber.
    tracing_subscriber::fmt::init();

    let token = env::var("DISCORD_TOKEN")?;
    let mut shard = Shard::new(ShardId::ONE, token, Intents::GUILD_MESSAGES);

    // Create a cache, caching up to 10 messages per channel:
    let cache = DefaultInMemoryCache::builder().message_cache_size(10).build();

    while let Some(item) = shard.next_event(EventTypeFlags::all()).await {
        let Ok(event) = item else {
            tracing::warn!(source = ?item.unwrap_err(), "error receiving event");

            continue;
        };

        // Update the cache with the event.
        cache.update(&event);
    }

    Ok(())
}

License

All first-party crates are licensed under ISC