feat: operations IDs are ordered by operation timestamp

internal/oplog/oplog.go

@@ -57,7 +57,10 @@ func NewOpLog(databasePath string) (*OpLog, error) {
 		return nil, fmt.Errorf("error opening database: %s", err)
 	}
 
-	o := &OpLog{db: db}
+	o := &OpLog{
+		db: db,
+	}
+	o.nextId.Store(1)
 
 	if err := db.Update(func(tx *bolt.Tx) error {
 		// Create the buckets if they don't exist
@@ -194,15 +197,15 @@ func (o *OpLog) getOperationHelper(b *bolt.Bucket, id int64) (*v1.Operation, err
 
 func (o *OpLog) addOperationHelper(tx *bolt.Tx, op *v1.Operation) error {
 	b := tx.Bucket(OpLogBucket)
-
 	if op.Id == 0 {
-		// Create a unique ID sorted based on the start time in milliseconds and
-		// a counter to ensure uniqueness in the case of multiple operations
-		// starting at the same time.
-		op.Id = op.UnixTimeStartMs<<20 | (o.nextId.Add(1) & (1<<20 - 1))
-		if op.Id < 0 {
-			return fmt.Errorf("overflow in operation ID generation")
+		seq, err := b.NextSequence()
+		if err != nil {
+			return fmt.Errorf("error getting next sequence: %w", err)
 		}
+		if op.UnixTimeStartMs == 0 {
+			return fmt.Errorf("operation must have a start time")
+		}
+		op.Id = op.UnixTimeStartMs<<20 | int64(seq&(1<<20-1))
 	}
 
 	op.SnapshotId = NormalizeSnapshotId(op.SnapshotId)

internal/orchestrator/tasks.go

@@ -47,6 +47,21 @@ func (t *ScheduledBackupTask) Name() string {
 }
 
 func (t *ScheduledBackupTask) Next(now time.Time) *time.Time {
+	if ops, err := t.orchestrator.OpLog.GetByPlan(t.plan.Id, indexutil.CollectLastN(10)); err == nil {
+		var lastBackupOp *v1.Operation
+		for _, op := range ops {
+			if _, ok := op.Op.(*v1.Operation_OperationBackup); ok {
+				lastBackupOp = op
+			}
+		}
+
+		if lastBackupOp != nil {
+			now = time.Unix(0, lastBackupOp.UnixTimeEndMs*int64(time.Millisecond))
+		}
+	} else {
+		zap.S().Errorf("error getting last operation for plan %q when computing backup schedule: %v", t.plan.Id, err)
+	}
+
 	next := t.schedule.Next(now)
 	return &next
 }
@@ -174,6 +189,7 @@ func indexSnapshotsHelper(ctx context.Context, orchestrator *Orchestrator, plan
 			UnixTimeStartMs: snapshotProto.UnixTimeMs,
 			UnixTimeEndMs:   snapshotProto.UnixTimeMs,
 			Status:          v1.OperationStatus_STATUS_SUCCESS,
+			SnapshotId:      snapshotProto.Id,
 			Op: &v1.Operation_OperationIndexSnapshot{
 				OperationIndexSnapshot: &v1.OperationIndexSnapshot{
 					Snapshot: snapshotProto,
@@ -196,15 +212,6 @@ func indexSnapshotsHelper(ctx context.Context, orchestrator *Orchestrator, plan
 	return err
 }
 
-func containsSnapshotOperation(ops []*v1.Operation) bool {
-	for _, op := range ops {
-		if _, ok := op.Op.(*v1.Operation_OperationIndexSnapshot); ok {
-			return true
-		}
-	}
-	return false
-}
-
 // WithOperation is a utility that creates an operation to track the function's execution.
 // timestamps are automatically added and the status is automatically updated if an error occurs.
 func WithOperation(oplog *oplog.OpLog, op *v1.Operation, do func() error) error {
@@ -233,3 +240,12 @@ func curTimeMillis() int64 {
 	t := time.Now()
 	return t.Unix()*1000 + int64(t.Nanosecond()/1000000)
 }
+
+func containsSnapshotOperation(ops []*v1.Operation) bool {
+	for _, op := range ops {
+		if _, ok := op.Op.(*v1.Operation_OperationIndexSnapshot); ok {
+			return true
+		}
+	}
+	return false
+}

proto/v1/operations.proto

@@ -12,13 +12,18 @@ message OperationList {
 
 message Operation {
   int64 id = 1;
-  string repo_id = 2; // repo id if associated with a repo (always true)
-  string plan_id = 3; // plan id if associated with a plan (always true)
-  string snapshot_id = 8; // snapshot id if associated with a snapshot.
+  // repo id if associated with a repo (always true)
+  string repo_id = 2; 
+  // plan id if associated with a plan (always true)
+  string plan_id = 3; 
+  // snapshot id if associated with a snapshot.
+  string snapshot_id = 8; 
   OperationStatus status = 4;
-  int64 unix_time_start_ms = 5;
+  // unix time in milliseconds of the operation's creation (ID is derived from this)
+  int64 unix_time_start_ms = 5; 
   int64 unix_time_end_ms = 6;
-  string display_message = 7; // human readable context message (if any)
+  // human readable context message, typically an error message.
+  string display_message = 7; 
 
   oneof op {
     OperationBackup operation_backup = 100;

webui/src/components/OperationList.tsx

@@ -100,17 +100,17 @@ export const OperationRow = ({
     color = "blue";
   }
 
+  let opType = "Message";
+  if (operation.operationBackup) {
+    opType = "Backup";
+  } else if (operation.operationIndexSnapshot) {
+    opType = "Snapshot";
+  }
+
   if (
     operation.displayMessage &&
     operation.status === OperationStatus.STATUS_ERROR
   ) {
-    let opType = "Message";
-    if (operation.operationBackup) {
-      opType = "Backup";
-    } else if (operation.operationIndexSnapshot) {
-      opType = "Snapshot";
-    }
-
     return (
       <List.Item>
         <List.Item.Meta