Fix bugs in rerunning jobs (#29955)

Fix #28761
Fix #27884
Fix #28093

## Changes

### Rerun all jobs
When rerun all jobs, status of the jobs with `needs` will be set to
`blocked` instead of `waiting`. Therefore, these jobs will not run until
the required jobs are completed.

### Rerun a single job
When a single job is rerun, its dependents should also be rerun, just
like GitHub does
(https://github.com/go-gitea/gitea/issues/28761#issuecomment-2008620820).
In this case, only the specified job will be set to `waiting`, its
dependents will be set to `blocked` to wait the job.

### Show warning if every job has `needs`
If every job in a workflow has `needs`, all jobs will be blocked and no
job can be run. So I add a warning message.

<img
src="https://github.com/go-gitea/gitea/assets/15528715/88f43511-2360-465d-be96-ee92b57ff67b"
width="480px" />

5 files changed, 117 insertions, 6 deletions

diff --git a/options/locale/locale_en-US.ini b/options/locale/locale_en-US.ini
index 3383bc0bcc..4c52c4eeed 100644
--- a/options/locale/locale_en-US.ini
+++ b/options/locale/locale_en-US.ini
@@ -3626,6 +3626,7 @@ runs.scheduled = Scheduled
 runs.pushed_by = pushed by
 runs.invalid_workflow_helper = Workflow config file is invalid. Please check your config file: %s
 runs.no_matching_online_runner_helper = No matching online runner with label: %s
+runs.no_job_without_needs = The workflow must contain at least one job without dependencies.
 runs.actor = Actor
 runs.status = Status
 runs.actors_no_select = All actors
diff --git a/routers/web/repo/actions/actions.go b/routers/web/repo/actions/actions.go
index f27329aa0f..6059ad1414 100644
--- a/routers/web/repo/actions/actions.go
+++ b/routers/web/repo/actions/actions.go
@@ -104,8 +104,13 @@ func List(ctx *context.Context) {
 				workflows = append(workflows, workflow)
 				continue
 			}
-			// Check whether have matching runner
+			// The workflow must contain at least one job without "needs". Otherwise, a deadlock will occur and no jobs will be able to run.
+			hasJobWithoutNeeds := false
+			// Check whether have matching runner and a job without "needs"
 			for _, j := range wf.Jobs {
+				if !hasJobWithoutNeeds && len(j.Needs()) == 0 {
+					hasJobWithoutNeeds = true
+				}
 				runsOnList := j.RunsOn()
 				for _, ro := range runsOnList {
 					if strings.Contains(ro, "${{") {
@@ -123,6 +128,9 @@ func List(ctx *context.Context) {
 					break
 				}
 			}
+			if !hasJobWithoutNeeds {
+				workflow.ErrMsg = ctx.Locale.TrString("actions.runs.no_job_without_needs")
+			}
 			workflows = append(workflows, workflow)
 		}
 	}
diff --git a/routers/web/repo/actions/view.go b/routers/web/repo/actions/view.go
index 3f8030e40d..41989589be 100644
--- a/routers/web/repo/actions/view.go
+++ b/routers/web/repo/actions/view.go
@@ -303,12 +303,25 @@ func Rerun(ctx *context_module.Context) {
 		return
 	}
 
-	if jobIndexStr != "" {
-		jobs = []*actions_model.ActionRunJob{job}
+	if jobIndexStr == "" { // rerun all jobs
+		for _, j := range jobs {
+			// if the job has needs, it should be set to "blocked" status to wait for other jobs
+			shouldBlock := len(j.Needs) > 0
+			if err := rerunJob(ctx, j, shouldBlock); err != nil {
+				ctx.Error(http.StatusInternalServerError, err.Error())
+				return
+			}
+		}
+		ctx.JSON(http.StatusOK, struct{}{})
+		return
 	}
 
-	for _, j := range jobs {
-		if err := rerunJob(ctx, j); err != nil {
+	rerunJobs := actions_service.GetAllRerunJobs(job, jobs)
+
+	for _, j := range rerunJobs {
+		// jobs other than the specified one should be set to "blocked" status
+		shouldBlock := j.JobID != job.JobID
+		if err := rerunJob(ctx, j, shouldBlock); err != nil {
 			ctx.Error(http.StatusInternalServerError, err.Error())
 			return
 		}
@@ -317,7 +330,7 @@ func Rerun(ctx *context_module.Context) {
 	ctx.JSON(http.StatusOK, struct{}{})
 }
 
-func rerunJob(ctx *context_module.Context, job *actions_model.ActionRunJob) error {
+func rerunJob(ctx *context_module.Context, job *actions_model.ActionRunJob, shouldBlock bool) error {
 	status := job.Status
 	if !status.IsDone() {
 		return nil
@@ -325,6 +338,9 @@ func rerunJob(ctx *context_module.Context, job *actions_model.ActionRunJob) erro
 
 	job.TaskID = 0
 	job.Status = actions_model.StatusWaiting
+	if shouldBlock {
+		job.Status = actions_model.StatusBlocked
+	}
 	job.Started = 0
 	job.Stopped = 0
 
diff --git a/services/actions/rerun.go b/services/actions/rerun.go
new file mode 100644
index 0000000000..60f6650905
--- /dev/null
+++ b/services/actions/rerun.go
@@ -0,0 +1,38 @@
+// Copyright 2024 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package actions
+
+import (
+	actions_model "code.gitea.io/gitea/models/actions"
+	"code.gitea.io/gitea/modules/container"
+)
+
+// GetAllRerunJobs get all jobs that need to be rerun when job should be rerun
+func GetAllRerunJobs(job *actions_model.ActionRunJob, allJobs []*actions_model.ActionRunJob) []*actions_model.ActionRunJob {
+	rerunJobs := []*actions_model.ActionRunJob{job}
+	rerunJobsIDSet := make(container.Set[string])
+	rerunJobsIDSet.Add(job.JobID)
+
+	for {
+		found := false
+		for _, j := range allJobs {
+			if rerunJobsIDSet.Contains(j.JobID) {
+				continue
+			}
+			for _, need := range j.Needs {
+				if rerunJobsIDSet.Contains(need) {
+					found = true
+					rerunJobs = append(rerunJobs, j)
+					rerunJobsIDSet.Add(j.JobID)
+					break
+				}
+			}
+		}
+		if !found {
+			break
+		}
+	}
+
+	return rerunJobs
+}
diff --git a/services/actions/rerun_test.go b/services/actions/rerun_test.go
new file mode 100644
index 0000000000..a98de7b788
--- /dev/null
+++ b/services/actions/rerun_test.go
@@ -0,0 +1,48 @@
+// Copyright 2024 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package actions
+
+import (
+	"testing"
+
+	actions_model "code.gitea.io/gitea/models/actions"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestGetAllRerunJobs(t *testing.T) {
+	job1 := &actions_model.ActionRunJob{JobID: "job1"}
+	job2 := &actions_model.ActionRunJob{JobID: "job2", Needs: []string{"job1"}}
+	job3 := &actions_model.ActionRunJob{JobID: "job3", Needs: []string{"job2"}}
+	job4 := &actions_model.ActionRunJob{JobID: "job4", Needs: []string{"job2", "job3"}}
+
+	jobs := []*actions_model.ActionRunJob{job1, job2, job3, job4}
+
+	testCases := []struct {
+		job       *actions_model.ActionRunJob
+		rerunJobs []*actions_model.ActionRunJob
+	}{
+		{
+			job1,
+			[]*actions_model.ActionRunJob{job1, job2, job3, job4},
+		},
+		{
+			job2,
+			[]*actions_model.ActionRunJob{job2, job3, job4},
+		},
+		{
+			job3,
+			[]*actions_model.ActionRunJob{job3, job4},
+		},
+		{
+			job4,
+			[]*actions_model.ActionRunJob{job4},
+		},
+	}
+
+	for _, tc := range testCases {
+		rerunJobs := GetAllRerunJobs(tc.job, jobs)
+		assert.ElementsMatch(t, tc.rerunJobs, rerunJobs)
+	}
+}