[BUG] - job.NextRub and job.LastRun not immediately available inside the job when the job begins

[daviesluke]

Describe the bug

When a job begins and a call is made to the NextRun or LastRun function inside the job function being executed then if it is requested too quickly within the job code then get the error -> "gocron: job not found"

To Reproduce

Steps to reproduce the behavior:

Here is some test code to reproduce the data

package main

import (
	"fmt"
	"sync"
	"time"

	"github.com/go-co-op/gocron/v2"
)

var job gocron.Job

func runJob() {
	fmt.Printf("Job %s starting\n", job.ID())

	// Get nextrun time
	if nextRun, err := job.NextRun(); err != nil {
		fmt.Printf("Error getting NextRun -> %v\n", err)
	} else {
		fmt.Printf("Got NextRun first time -> %v\n", nextRun)
	}

	time.Sleep(100 * time.Millisecond)

	if nextRun, err := job.NextRun(); err != nil {
		fmt.Printf("Error getting NextRun -> %v\n", err)
	} else {
		fmt.Printf("Got NextRun second time -> %v\n", nextRun)
	}
	fmt.Printf("Job %s complete\n", job.ID())
}

func main() {
	fmt.Println("Creating the scheduler")

	newSched, _ := gocron.NewScheduler()

	job, _ = newSched.NewJob(
		gocron.DurationJob(10*time.Second),
		gocron.NewTask(runJob),
	)

	fmt.Printf("Job %s created\n", job.ID())

	newSched.Start()

	fmt.Println("Scheduler Started")

	// Waiting forever - interrupt to quit
	wg := &sync.WaitGroup{}
	wg.Add(1)
	wg.Wait()

	// Not necessary just for documentation
	newSched.Shutdown()
}

This is the output received

Creating the scheduler
Job 263bf685-fb4d-4155-b9b2-a6314a4c2cf5 created
Scheduler Started
Job 263bf685-fb4d-4155-b9b2-a6314a4c2cf5 starting
Error getting NextRun -> gocron: job not found
Got NextRun second time -> 2024-03-12 15:12:48.750701944 +0000 GMT
Job 263bf685-fb4d-4155-b9b2-a6314a4c2cf5 complete
Job 263bf685-fb4d-4155-b9b2-a6314a4c2cf5 starting
Error getting NextRun -> gocron: job not found
Got NextRun second time -> 2024-03-12 15:12:58.750701944 +0000 GMT
Job 263bf685-fb4d-4155-b9b2-a6314a4c2cf5 complete
^C

Version

V2.5.2

Expected behavior

Expected to be able to examine NextRun and LastRun output immediately on job start

Additional context

None

[JohnRoesler]

Hey @daviesluke i'm not able to reproduce this. Running the same code you provided:

I get

Creating the scheduler
Job 2f6f1077-940c-4279-95a8-72993c1ff0e6 created
Scheduler Started
Job 2f6f1077-940c-4279-95a8-72993c1ff0e6 starting
Got NextRun first time -> 2024-03-13 21:17:30.576713
Got NextRun second time -> 2024-03-13 21:17:30.576713
Job 2f6f1077-940c-4279-95a8-72993c1ff0e6 complete

[daviesluke]

Yes I also receive intermittent results

[oracle@orabox test_nextrun]$ ./test_nextrun
Creating the scheduler
Job bb40a041-602b-4e12-a158-288638d1c0a1 created
Scheduler Started
Job bb40a041-602b-4e12-a158-288638d1c0a1 starting
Got NextRun first time -> 2024-03-15 10:29:15.79272006 +0000 GMT
Got NextRun second time -> 2024-03-15 10:29:15.79272006 +0000 GMT
Job bb40a041-602b-4e12-a158-288638d1c0a1 complete
^C
[oracle@orabox test_nextrun]$ ./test_nextrun
Creating the scheduler
Job e19c12dc-dd9b-40de-97d5-ac5217a0b8d2 created
Scheduler Started
Job e19c12dc-dd9b-40de-97d5-ac5217a0b8d2 starting
Error getting NextRun -> gocron: job not found
Got NextRun second time -> 2024-03-15 10:29:30.795880785 +0000 GMT
Job e19c12dc-dd9b-40de-97d5-ac5217a0b8d2 complete
^C
[oracle@orabox test_nextrun]$ ./test_nextrun
Creating the scheduler
Job 31e77aac-c091-4601-98e8-bc91a4b68d81 created
Scheduler Started
Job 31e77aac-c091-4601-98e8-bc91a4b68d81 starting
Error getting NextRun -> gocron: job not found
Got NextRun second time -> 2024-03-15 10:29:56.283641162 +0000 GMT
Job 31e77aac-c091-4601-98e8-bc91a4b68d81 complete
Job 31e77aac-c091-4601-98e8-bc91a4b68d81 starting
Error getting NextRun -> gocron: job not found
Got NextRun second time -> 2024-03-15 10:30:06.283641162 +0000 GMT
Job 31e77aac-c091-4601-98e8-bc91a4b68d81 complete
Job 31e77aac-c091-4601-98e8-bc91a4b68d81 starting
Got NextRun first time -> 2024-03-15 10:30:16.283641162 +0000 GMT
Got NextRun second time -> 2024-03-15 10:30:16.283641162 +0000 GMT
Job 31e77aac-c091-4601-98e8-bc91a4b68d81 complete
^C

[JohnRoesler]

I believe this is solved by #699