Init commit of jobs output/error message peek project.

src/frontend/apiserver/backend/convert_pure.go

@@ -3,6 +3,7 @@ package backend
 import (
 	"apiserver/models"
 	"encoding/json"
+	"fmt"
 	"time"
 )
 
@@ -76,6 +77,33 @@ func IsArrayJob(id uint64) bool {
 	return extractIDTag(id) == tagJobArray
 }
 
+// FormatJobID formats a packed 64-bit job ID as a human-readable string,
+// matching the C fmt_jobid() output in src/lib/utils.c.
+//   - Regular job:  "{cluster}-{apiserver}-{timestamp}-{sequence}"
+//   - Array child:  "{cluster}-{apiserver}-{timestamp}-{base}[{idx}]"
+func FormatJobID(uniqueJobID int64) string {
+	id := uint64(uniqueJobID)
+	clusterID := extractBits(id, clusterIDShift, nClusterIDBits)
+	apiserverID := extractBits(id, apiserverIDShift, nApiserverIDBits)
+	timestamp := extractBits(id, timestampShift, nTimestampBits)
+
+	if extractIDTag(id) == tagJobArray {
+		arrayBase := extractBits(id, sequenceHighShift, nSequenceBits-nArrayIdxBits) << uint(sequenceHighShift)
+		arrayIdx := extractBits(id, 0, nArrayIdxBits)
+		return fmt.Sprintf("%d-%d-%d-%d[%d]",
+			clusterID, apiserverID, timestamp, arrayBase, arrayIdx)
+	}
+	sequence := extractBits(id, 0, nSequenceBits)
+	return fmt.Sprintf("%d-%d-%d-%d",
+		clusterID, apiserverID, timestamp, sequence)
+}
+
+// WorkerDefaultOutputPath returns the output file path the worker uses by default
+// for the given job ID and task index, matching uv_proc.c make_job_output_path().
+func WorkerDefaultOutputPath(uniqueJobID int64, taskIdx int) string {
+	return fmt.Sprintf("/tmp/job_%s_task%d.out", FormatJobID(uniqueJobID), taskIdx)
+}
+
 // rawStartInfo mirrors the C job_startinfo_t fields used by the Go model.
 type rawStartInfo struct {
 	cmdline    string