Files
tuwunel/src/service/service.rs
2025-09-23 05:16:29 +00:00

56 lines
2.0 KiB
Rust

use std::{any::Any, fmt::Write, sync::Arc};
use async_trait::async_trait;
use tuwunel_core::{Result, Server, utils::string::SplitInfallible};
use tuwunel_database::Database;
use crate::services::OnceServices;
/// Abstract interface for a Service
#[async_trait]
pub(crate) trait Service: Any + Send + Sync {
/// Implement the construction of the service instance. Services are
/// generally singletons so expect this to only be called once for a
/// service type. Note that it may be called again after a server reload,
/// but the prior instance will have been dropped first. Failure will
/// shutdown the server with an error.
fn build(args: &Args<'_>) -> Result<Arc<impl Service>>
where
Self: Sized;
/// Implement the service's worker loop. The service manager spawns a
/// task and calls this function after all services have been built.
async fn worker(self: Arc<Self>) -> Result { Ok(()) }
/// Interrupt the service. This is sent to initiate a graceful shutdown.
/// The service worker should return from its work loop.
async fn interrupt(&self) {}
/// Clear any caches or similar runtime state.
async fn clear_cache(&self) {}
/// Memory usage report in a markdown string.
async fn memory_usage(&self, _out: &mut (dyn Write + Send)) -> Result { Ok(()) }
/// Return the name of the service.
/// i.e. `crate::service::make_name(std::module_path!())`
fn name(&self) -> &str;
/// Return true if the service worker opts out of the tokio cooperative
/// budgeting. This can reduce tail latency at the risk of event loop
/// starvation.
fn unconstrained(&self) -> bool { false }
}
/// Args are passed to `Service::build` when a service is constructed. This
/// allows for arguments to change with limited impact to the many services.
pub(crate) struct Args<'a> {
pub(crate) server: &'a Arc<Server>,
pub(crate) db: &'a Arc<Database>,
pub(crate) services: &'a Arc<OnceServices>,
}
/// Utility for service implementations; see Service::name() in the trait.
#[inline]
pub(crate) fn make_name(module_path: &str) -> &str { module_path.split_once_infallible("::").1 }