#cron #cron-expression #job #scheduler #schedule #function

cron-job

A cronjob implementation using the cron scheduler

4 releases

0.1.4 Nov 2, 2023
0.1.2 Jun 6, 2023
0.1.1 Jun 6, 2023
0.1.0 Mar 14, 2023

#7 in #cron-expression

MIT license

11KB
83 lines

cron-job crates.io crates.io docs

The cron-job library lets you create cronjobs. This is basically an implementation of the cron library.

Getting started

Add this to your project:

[dependencies]
cron_job = "0.1.3"

Examples

You can schedule your own functions as jobs.

extern crate cron_job;
use cron_job::CronJob;

fn main() {
    // Create CronJob
    let mut cron = CronJob::default();
    // Add the function
    cron.new_job("* * * * * *", run_on_cron);
    // Start job
    cron.start();
}

// The function to be executed.
fn run_on_cron() {
    println!("Executed function");
}

Multiple functions with different cron expression can also be added.

extern crate cron_job;
use cron_job::CronJob;

fn main() {
    // Create CronJob
    let mut cron = CronJob::default();
    // Add the function to be run every second
    cron.new_job("* * * * * *", run_every_second);
    // Add the function to be run every 5 seconds
    cron.new_job("*/5 * * * * *", run_every_five_seconds);
    // Start jobs
    cron.start();
}

// The function to be executed every second.
fn run_every_second() {
    println!("1 second");
}

// The function to be executed every 5 seconds.
fn run_every_five_seconds() {
    println!("5 seconds");
}

Running jobs implementing Job trait

Since the function used as job cannot have any parameters, the Job trait is available to be implemented to structs. This way if any parameter needs to be passed to the function, can be passed as the struct property.

extern crate cron_job;
use cron_job::CronJob;

fn main() {
    // Create HelloJob
    let helloJob = HelloJob{ name: "John" };
    // Create CronJob
    let mut cron = CronJob::default();
    // Say hello every second
    cron.new_job("* * * * * *", helloJob);
    // Start jobs
    cron.start();
}

// The job to be executed
struct HelloJob {
    name: String
}

impl Job for HelloJob {
    fn run(&self) {
        println!("Hello, {}!", self.name);
    }
}

Functions and job can also be mixed together.

extern crate cron_job;
use cron_job::CronJob;

fn main() {
    // Create HelloJob
    let helloJob = HelloJob{ name: "John" };
    // Create CronJob
    let mut cron = CronJob::default();
    // Run function every second
    cron.new_job("* * * * * *", run_every_second);
    // Say hello every second
    cron.new_job("* * * * * *", helloJob);
    // Start jobs
    cron.start();
}
// The function to be executed every second.
fn run_every_second() {
    println!("1 second");
}

// The job to be executed
struct HelloJob {
    name: String
}

// Very important, implement the Job trait and its functions.
impl Job for HelloJob {
    fn run(&self) {
        println!("Hello, {}!", self.name);
    }
}

Dependencies

~2–8.5MB
~47K SLoC