dipeshdulal / event-scheduling

Golang Event Scheduling Sample Using Postgresql Database as persisting layer.

Database Based Event Scheduling

Example that demonstrates super basic database based event scheduling.

To run this example;

• Copy .env.example to .env and update postgres database dsn.
• Run go run .

Basically,

• When we want to schedule a job, we add to database

scheduler.Schedule("SendEmail", "mail: [e-mail]", time.Now().Add(1*time.Minute)) 

• Another go routine is always looking for jobs to execute (that has time expired) in the given interval.

scheduler.CheckEventsInInterval(ctx, time.Minute)

Output looks like;

2021/01/16 11:58:49 💾 Seeding database with table...
2021/01/16 11:58:49 🚀 Scheduling event SendEmail to run at 2021-01-16 11:59:49.344904505 +0545 +0545 m=+60.004623549
2021/01/16 11:58:49 🚀 Scheduling event PayBills to run at 2021-01-16 12:00:49.34773798 +0545 +0545 m=+120.007457039
2021/01/16 11:59:49 ⏰ Ticks Received...
2021/01/16 11:59:49 📨 Sending email with data:  mail: [e-mail]
2021/01/16 12:00:49 ⏰ Ticks Received...
2021/01/16 12:01:49 ⏰ Ticks Received...
2021/01/16 12:01:49 💲 Pay me a bill:  paybills: $4,000 bill
2021/01/16 12:02:49 ⏰ Ticks Received...
2021/01/16 12:03:49 ⏰ Ticks Received...
^C2021/01/16 12:03:57 
❌ Interrupt received closing...