chore(actions): support cron schedule task (#26655)

Replace #22751 

1. only support the default branch in the repository setting.
2. autoload schedule data from the schedule table after starting the
service.
3. support specific syntax like `@yearly`, `@monthly`, `@weekly`,
`@daily`, `@hourly`

## How to use

See the [GitHub Actions
document](https://docs.github.com/en/actions/using-workflows/events-that-trigger-workflows#schedule)
for getting more detailed information.

```yaml
on:
  schedule:
    - cron: '30 5 * * 1,3'
    - cron: '30 5 * * 2,4'

jobs:
  test_schedule:
    runs-on: ubuntu-latest
    steps:
      - name: Not on Monday or Wednesday
        if: github.event.schedule != '30 5 * * 1,3'
        run: echo "This step will be skipped on Monday and Wednesday"
      - name: Every time
        run: echo "This step will always run"
```

Signed-off-by: Bo-Yi.Wu <appleboy.tw@gmail.com>

---------


Co-authored-by: Jason Song <i@wolfogre.com>
Co-authored-by: techknowlogick <techknowlogick@gitea.io>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>

services/actions/schedule_tasks.go

@@ -0,0 +1,135 @@
+// Copyright 2023 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package actions
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	actions_model "code.gitea.io/gitea/models/actions"
+	"code.gitea.io/gitea/models/db"
+	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/modules/timeutil"
+	webhook_module "code.gitea.io/gitea/modules/webhook"
+
+	"github.com/nektos/act/pkg/jobparser"
+)
+
+// StartScheduleTasks start the task
+func StartScheduleTasks(ctx context.Context) error {
+	return startTasks(ctx)
+}
+
+// startTasks retrieves specifications in pages, creates a schedule task for each specification,
+// and updates the specification's next run time and previous run time.
+// The function returns an error if there's an issue with finding or updating the specifications.
+func startTasks(ctx context.Context) error {
+	// Set the page size
+	pageSize := 50
+
+	// Retrieve specs in pages until all specs have been retrieved
+	now := time.Now()
+	for page := 1; ; page++ {
+		// Retrieve the specs for the current page
+		specs, _, err := actions_model.FindSpecs(ctx, actions_model.FindSpecOptions{
+			ListOptions: db.ListOptions{
+				Page:     page,
+				PageSize: pageSize,
+			},
+			Next: now.Unix(),
+		})
+		if err != nil {
+			return fmt.Errorf("find specs: %w", err)
+		}
+
+		// Loop through each spec and create a schedule task for it
+		for _, row := range specs {
+			// cancel running jobs if the event is push
+			if row.Schedule.Event == webhook_module.HookEventPush {
+				// cancel running jobs of the same workflow
+				if err := actions_model.CancelRunningJobs(
+					ctx,
+					row.RepoID,
+					row.Schedule.Ref,
+					row.Schedule.WorkflowID,
+				); err != nil {
+					log.Error("CancelRunningJobs: %v", err)
+				}
+			}
+
+			if err := CreateScheduleTask(ctx, row.Schedule); err != nil {
+				log.Error("CreateScheduleTask: %v", err)
+				return err
+			}
+
+			// Parse the spec
+			schedule, err := row.Parse()
+			if err != nil {
+				log.Error("Parse: %v", err)
+				return err
+			}
+
+			// Update the spec's next run time and previous run time
+			row.Prev = row.Next
+			row.Next = timeutil.TimeStamp(schedule.Next(now.Add(1 * time.Minute)).Unix())
+			if err := actions_model.UpdateScheduleSpec(ctx, row, "prev", "next"); err != nil {
+				log.Error("UpdateScheduleSpec: %v", err)
+				return err
+			}
+		}
+
+		// Stop if all specs have been retrieved
+		if len(specs) < pageSize {
+			break
+		}
+	}
+
+	return nil
+}
+
+// CreateScheduleTask creates a scheduled task from a cron action schedule.
+// It creates an action run based on the schedule, inserts it into the database, and creates commit statuses for each job.
+func CreateScheduleTask(ctx context.Context, cron *actions_model.ActionSchedule) error {
+	// Create a new action run based on the schedule
+	run := &actions_model.ActionRun{
+		Title:         cron.Title,
+		RepoID:        cron.RepoID,
+		OwnerID:       cron.OwnerID,
+		WorkflowID:    cron.WorkflowID,
+		TriggerUserID: cron.TriggerUserID,
+		Ref:           cron.Ref,
+		CommitSHA:     cron.CommitSHA,
+		Event:         cron.Event,
+		EventPayload:  cron.EventPayload,
+		Status:        actions_model.StatusWaiting,
+	}
+
+	// Parse the workflow specification from the cron schedule
+	workflows, err := jobparser.Parse(cron.Content)
+	if err != nil {
+		return err
+	}
+
+	// Insert the action run and its associated jobs into the database
+	if err := actions_model.InsertRun(ctx, run, workflows); err != nil {
+		return err
+	}
+
+	// Retrieve the jobs for the newly created action run
+	jobs, _, err := actions_model.FindRunJobs(ctx, actions_model.FindRunJobOptions{RunID: run.ID})
+	if err != nil {
+		return err
+	}
+
+	// Create commit statuses for each job
+	for _, job := range jobs {
+		if err := createCommitStatus(ctx, job); err != nil {
+			return err
+		}
+	}
+
+	// Return nil if no errors occurred
+	return nil
+}