Basic Example

package main

import (
    "context"
    "fmt"
    "github.com/gogf/gf/v2/os/gctx"
    "github.com/gogf/gf/v2/os/gtime"
    "github.com/gogf/gf/v2/os/gtimer"
    "time"
)

func main() {
    var (
        ctx = gctx.New()
        now = time.Now()
    )
    gtimer.AddTimes(ctx, time.Second, 10, func(ctx context.Context) {
        fmt.Println(gtime.Now(), time.Duration(time.Now().UnixNano()-now.UnixNano()))
        now = time.Now()
    })

    select {}
}

After execution, the output is:

2021-05-27 13:28:19 1.004516s
2021-05-27 13:28:20 997.262ms
2021-05-27 13:28:21 999.972ms
2021-05-27 13:28:22 1.00112s
2021-05-27 13:28:23 998.773ms
2021-05-27 13:28:24 999.957ms
2021-05-27 13:28:25 1.002468s
2021-05-27 13:28:26 997.468ms
2021-05-27 13:28:27 999.981ms
2021-05-27 13:28:28 1.002504s

Singleton Task

package main

import (
    "context"
    "github.com/gogf/gf/v2/os/gctx"
    "github.com/gogf/gf/v2/os/glog"
    "github.com/gogf/gf/v2/os/gtimer"
    "time"
)

func main() {
    var (
        ctx      = gctx.New()
        interval = time.Second
    )

    gtimer.AddSingleton(ctx, interval, func(ctx context.Context) {
        glog.Print(ctx, "doing")
        time.Sleep(5 * time.Second)
    })

    select {}
}

After execution, the output is:

2021-11-14 11:50:42.192 {189cwi9mo40cfp73guzhugo100tnuedg} doing
2021-11-14 11:50:48.190 {189cwi9mo40cfp73guzhugo100tnuedg} doing
2021-11-14 11:50:54.192 {189cwi9mo40cfp73guzhugo100tnuedg} doing
2021-11-14 11:51:00.189 {189cwi9mo40cfp73guzhugo100tnuedg} doing
...

Delayed Task

Delayed tasks refer to scheduled tasks that take effect after a specified time. We can create delayed tasks using DelayAdd* related methods.

package main

import (
    "context"
    "fmt"
    "github.com/gogf/gf/v2/os/gctx"
    "github.com/gogf/gf/v2/os/gtime"
    "github.com/gogf/gf/v2/os/gtimer"
    "time"
)

func main() {
    var (
        ctx      = gctx.New()
        delay    = time.Second
        interval = time.Second
    )
    fmt.Println("Start:", gtime.Now())
    gtimer.DelayAdd(
        ctx,
        delay,
        interval,
        func(ctx context.Context) {
            fmt.Println("Running:", gtime.Now())
        },
    )
    select {}
}

After execution, the terminal output is:

Start: 2021-05-27 13:26:02
Running: 2021-05-27 13:26:04
Running: 2021-05-27 13:26:05
Running: 2021-05-27 13:26:06
Running: 2021-05-27 13:26:07
Running: 2021-05-27 13:26:08
Running: 2021-05-27 13:26:09
Running: 2021-05-27 13:26:10
Running: 2021-05-27 13:26:11
...

SetTimeout and SetInterval

These two methods are common scheduling methods from JavaScript. SetTimeout is used to create a scheduled task that executes only once. However, you can achieve infinite interval execution through recursive calls to SetTimeout. SetInterval is used to create scheduled tasks that execute at intervals without exiting.

package main

import (
    "context"
    "fmt"
    "github.com/gogf/gf/v2/os/gctx"
    "github.com/gogf/gf/v2/os/gtime"
    "github.com/gogf/gf/v2/os/gtimer"
    "time"
)

func main() {
    var (
        ctx      = gctx.New()
        timeout  = time.Second
        interval = time.Second
    )
    gtimer.SetTimeout(ctx, timeout, func(ctx context.Context) {
        fmt.Println("SetTimeout:", gtime.Now())
    })
    gtimer.SetInterval(ctx, interval, func(ctx context.Context) {
        fmt.Println("SetInterval:", gtime.Now())
    })
    select {}
}

After execution, the terminal output is:

SetInterval: 2021-05-27 13:20:50
SetTimeout: 2021-05-27 13:20:50
SetInterval: 2021-05-27 13:20:51
SetInterval: 2021-05-27 13:20:52
SetInterval: 2021-05-27 13:20:53
SetInterval: 2021-05-27 13:20:54
SetInterval: 2021-05-27 13:20:55
SetInterval: 2021-05-27 13:20:56
SetInterval: 2021-05-27 13:20:57
SetInterval: 2021-05-27 13:20:58
...

Exit Method to Exit

We can use the Exit method in scheduled tasks to forcefully exit the continuation of the task, which will then be removed from the scheduler.

package main

import (
    "context"
    "fmt"
    "github.com/gogf/gf/v2/os/gctx"
    "github.com/gogf/gf/v2/os/gtime"
    "github.com/gogf/gf/v2/os/gtimer"
    "time"
)

func main() {
    var (
        ctx = gctx.New()
    )
    gtimer.SetInterval(ctx, time.Second, func(ctx context.Context) {
        fmt.Println("exit:", gtime.Now())
        gtimer.Exit()
    })
    select {}
}

After execution, the terminal output is:

exit: 2021-05-27 13:31:24