refactor: clarify logging for parallel WAL archiving (#113)

Differentiate between the WAL archived and the ones pre-archived by the
parallel workers.

Signed-off-by: Francesco Canovai <[email protected]>
Signed-off-by: Armando Ruocco <[email protected]>
Co-authored-by: Armando Ruocco <[email protected]>

Author: fcanovai

pkg/walarchive/cmd.go

@@ -109,34 +109,43 @@ func (archiver *BarmanArchiver) ArchiveList(
 	for idx := range walNames {
 		waitGroup.Add(1)
 		go func(walIndex int) {
-			walStatus := &result[walIndex]
-			walStatus.WalName = walNames[walIndex]
-			walStatus.StartTime = time.Now()
-			walStatus.Err = archiver.Archive(ctx, walNames[walIndex], options)
-			walStatus.EndTime = time.Now()
-			if walStatus.Err == nil && walIndex != 0 {
-				walStatus.Err = archiver.Touch(walNames[walIndex])
+			defer waitGroup.Done()
+
+			result[walIndex] = WALArchiverResult{
+				WalName:   walNames[walIndex],
+				StartTime: time.Now(),
+				Err:       archiver.Archive(ctx, walNames[walIndex], options),
+				EndTime:   time.Now(),
 			}
+			walStatus := &result[walIndex]
+
+			walContextLog := contextLog.WithValues(
+				"walName", walStatus.WalName,
+				"startTime", walStatus.StartTime,
+				"endTime", walStatus.EndTime,
+				"elapsedWalTime", walStatus.EndTime.Sub(walStatus.StartTime),
+			)
 
-			elapsedWalTime := walStatus.EndTime.Sub(walStatus.StartTime)
 			if walStatus.Err != nil {
-				contextLog.Warning(
+				walContextLog.Warning(
 					"Failed archiving WAL: PostgreSQL will retry",
-					"walName", walStatus.WalName,
-					"startTime", walStatus.StartTime,
-					"endTime", walStatus.EndTime,
-					"elapsedWalTime", elapsedWalTime,
 					"error", walStatus.Err)
-			} else {
-				contextLog.Info(
-					"Archived WAL file",
-					"walName", walStatus.WalName,
-					"startTime", walStatus.StartTime,
-					"endTime", walStatus.EndTime,
-					"elapsedWalTime", elapsedWalTime)
+				return
+			}
+
+			if walIndex == 0 {
+				walContextLog.Info("Archived WAL file")
+				return
+			}
+
+			if err := archiver.Touch(walNames[walIndex]); err != nil {
+				walContextLog.Warning(
+					"WAL file pre-archived, but it could not be added to the spool. PostgreSQL will retry",
+					"error", err)
+				return
 			}
 
-			waitGroup.Done()
+			walContextLog.Info("Pre-archived WAL file (parallel)")
 		}(idx)
 	}