apalis-mysql

Background task processing in rust using apalis and mysql

Features

• Reliable job queue using MySql as the backend.
• Multiple storage types: standard polling and trigger based storages.
• Custom codecs for serializing/deserializing job arguments as bytes.
• Heartbeat and orphaned job re-enqueueing for robust task processing.
• Integration with apalis workers and middleware.
• Observability: Monitor and manage tasks using apalis-board.

Storage Types

• [MySqlStorage]: Standard polling-based storage.
• [SharedMySqlStorage]: Shared storage for multiple job types, reuses the connection.

The naming is designed to clearly indicate the storage mechanism and its capabilities, but under the hood the result is the MySqlStorage struct with different configurations.

Setting up

You need a working MySql server setup. Here is a quick command using docker.

docker run -d --name test-mysql -e MYSQL_ROOT_PASSWORD=strong_password -p 3306:3306 mysql

Examples

Basic Worker Example

use apalis_mysql::*;
use futures::stream::{self, StreamExt};
use apalis::prelude::*;
use std::time::Duration;

#[tokio::main]
async fn main() {
    let pool = MySqlPool::connect(env!("DATABASE_URL")).await.unwrap();
    MySqlStorage::setup(&pool).await.unwrap();
    let mut backend = MySqlStorage::new(&pool);

    let mut start = 0;
    let mut items = stream::repeat_with(move || {
        start += 1;
        let task = Task::builder(start)
            .run_after(Duration::from_secs(1))
            .priority(1)
            .build();
        task
    })
    .take(10);
    backend.push_all(&mut items).await.unwrap();

    async fn send_reminder(item: usize, wrk: WorkerContext) -> Result<(), BoxDynError> {
        Ok(())
    }

    let worker = WorkerBuilder::new("worker-1")
        .backend(backend)
        .build(send_reminder);
    worker.run().await.unwrap();
}

Workflow Example

use apalis_mysql::*;
use apalis::prelude::*;
use std::time::Duration;
use apalis_workflow::*;

#[tokio::main]
async fn main() {
    let workflow = Workflow::new("odd-numbers-workflow")
        .and_then(|a: usize| async move {
            Ok::<_, BoxDynError>((0..=a).collect::<Vec<_>>())
        })
        .filter_map(|x| async move {
            if x % 2 != 0 { Some(x) } else { None }
        })
        .filter_map(|x| async move {
            if x % 3 != 0 { Some(x) } else { None }
        })
        .filter_map(|x| async move {
            if x % 5 != 0 { Some(x) } else { None }
        })
        .delay_for(Duration::from_millis(1000))
        .and_then(|a: Vec<usize>| async move {
            println!("Sum: {}", a.iter().sum::<usize>());
            Ok::<(), BoxDynError>(())
        });

    let pool = MySqlPool::connect(env!("DATABASE_URL")).await.unwrap();
    MySqlStorage::setup(&pool).await.unwrap();
    let mut backend = MySqlStorage::new_in_queue(&pool, "test-workflow");

    backend.push_start(100usize).await.unwrap();

    let worker = WorkerBuilder::new("rango-tango")
        .backend(backend)
        .on_event(|ctx, ev| {
            println!("On Event = {:?}", ev);
            if matches!(ev, Event::Error(_)) {
                ctx.stop().unwrap();
            }
        })
        .build(workflow);

    worker.run().await.unwrap();
}

Shared Example

This shows an example of multiple backends using the same connection. This can improve performance if you have many types of jobs.

use apalis_mysql::*;
use futures::stream;
use apalis::prelude::*;
use std::time::Duration;

#[tokio::main]
async fn main() {
    let pool = MySqlPool::connect(env!("DATABASE_URL"))
        .await
        .unwrap();
    let mut store = SharedMySqlStorage::new(pool);

    let mut map_store = store.make_shared().unwrap();

    let mut int_store = store.make_shared().unwrap();

    map_store
        .push_stream(&mut stream::iter(vec![HashMap::<String, String>::new()]))
        .await
        .unwrap();
    int_store.push(99).await.unwrap();

    async fn send_reminder<T, I>(
        _: T,
        task_id: TaskId<I>,
        wrk: WorkerContext,
    ) -> Result<(), BoxDynError> {
        tokio::time::sleep(Duration::from_secs(2)).await;
        wrk.stop().unwrap();
        Ok(())
    }

    let int_worker = WorkerBuilder::new("rango-tango-2")
        .backend(int_store)
        .build(send_reminder);
    let map_worker = WorkerBuilder::new("rango-tango-1")
        .backend(map_store)
        .build(send_reminder);
    tokio::try_join!(int_worker.run(), map_worker.run()).unwrap();
}

Observability

You can track your jobs using apalis-board.

License

Licensed under either of Apache License, Version 2.0 or MIT license at your option.