enhance: log task, job and run identifiers when a task starts (#1257)

Replace the `task N repo is ...` line with a structured `task started` entry carrying `task_id`, `job_id`, `run_id`, `run_number`, `repository` and the workflow's `job` key, so external supervisors can match runner activity to the job in Gitea. `job_id` is read from the runtime token's claims, tokens and secrets are never logged.

Closes https://gitea.com/gitea/runner/issues/752

---------

Co-authored-by: silverwind <[email protected]>
Co-authored-by: silverwind <[email protected]>
Reviewed-on: https://gitea.com/gitea/runner/pulls/1257
Reviewed-by: silverwind <[email protected]>

internal/app/run/runner.go

@@ -7,6 +7,7 @@ import (
 	"bytes"
 	"cmp"
 	"context"
+	"encoding/base64"
 	"encoding/json/v2"
 	"errors"
 	"fmt"
@@ -424,6 +425,10 @@ func (r *Runner) run(ctx context.Context, task *runnerv1.Task, reporter *report.
 	if err != nil {
 		return err
 	}
+	log.WithFields(taskLogFields(task, jobID)).
+		WithField("actions_url", r.getDefaultActionsURL(task)).
+		WithField("address", r.client.Address()).
+		Info("task started")
 
 	plan, err := model.CombineWorkflowPlanner(workflow).PlanJob(jobID)
 	if err != nil {
@@ -464,10 +469,6 @@ func (r *Runner) run(ctx context.Context, task *runnerv1.Task, reporter *report.
 	}
 	telemetry.AddJobEnv(ctx, envs)
 
-	log.Infof("task %v repo is %v %v %v", task.Id, taskContext["repository"].GetStringValue(),
-		r.getDefaultActionsURL(task),
-		r.client.Address())
-
 	preset := model.GithubContextFromMap(task.Context.AsMap())
 	if t := task.Secrets["GITEA_TOKEN"]; t != "" {
 		preset.Token = t
@@ -896,3 +897,22 @@ func (r *Runner) detectIsolatedCacheContainer() string {
 	}
 	return cacheContainer
 }
+
+func taskLogFields(task *runnerv1.Task, job string) log.Fields {
+	taskContext := task.GetContext().GetFields()
+	fields := log.Fields{
+		"task_id":    task.Id,
+		"job":        job,
+		"repository": taskContext["repository"].GetStringValue(),
+		"run_id":     taskContext["run_id"].GetStringValue(),
+		"run_number": taskContext["run_number"].GetStringValue(),
+	}
+	if parts := strings.Split(taskContext["gitea_runtime_token"].GetStringValue(), "."); len(parts) == 3 {
+		var claims struct{ JobID int64 } // Gitea's actionsClaims fields are untagged, so the claim key is "JobID"
+		payload, err := base64.RawURLEncoding.DecodeString(parts[1])
+		if err == nil && json.Unmarshal(payload, &claims) == nil && claims.JobID > 0 {
+			fields["job_id"] = claims.JobID
+		}
+	}
+	return fields
+}