dashboard/app: add handler for config migration

updateBugReporting adds missing reporting stages to bugs in a single namespace.
Use with care. There is no undo.
This can be used to migrate datastore to a new config with more reporting stages.
This functionality is intentionally not connected to any handler.
Before invoking it is recommented to stop all connected instances just in case.

2 files changed, 78 insertions, 8 deletions

diff --git a/dashboard/app/admin.go b/dashboard/app/admin.go
index db122297a..ce14a067c 100644
--- a/dashboard/app/admin.go
+++ b/dashboard/app/admin.go
@@ -80,8 +80,6 @@ func dropNamespace(c context.Context, w http.ResponseWriter, r *http.Request) er
 	return nil
 }
 
-var _ = dropNamespace // prevent warnings about dead code
-
 func dropNamespaceReportingState(c context.Context, w http.ResponseWriter, ns string, dryRun bool) error {
 	tx := func(c context.Context) error {
 		state, err := loadReportingState(c)
@@ -121,3 +119,70 @@ func dropEntities(c context.Context, keys []*datastore.Key, dryRun bool) error {
 	}
 	return nil
 }
+
+// updateBugReporting adds missing reporting stages to bugs in a single namespace.
+// Use with care. There is no undo.
+// This can be used to migrate datastore to a new config with more reporting stages.
+// This functionality is intentionally not connected to any handler.
+// Before invoking it is recommended to stop all connected instances just in case.
+func updateBugReporting(c context.Context, w http.ResponseWriter, r *http.Request) error {
+	if accessLevel(c, r) != AccessAdmin {
+		return fmt.Errorf("admin only")
+	}
+	ns := r.FormValue("ns")
+	if ns == "" {
+		return fmt.Errorf("no ns parameter")
+	}
+	var bugs []*Bug
+	keys, err := datastore.NewQuery("Bug").
+		Filter("Namespace=", ns).
+		GetAll(c, &bugs)
+	if err != nil {
+		return err
+	}
+	log.Warningf(c, "fetched %v bugs for namespce %v", len(bugs), ns)
+	cfg := config.Namespaces[ns]
+	var batchKeys []*datastore.Key
+	const batchSize = 20
+	for i, bug := range bugs {
+		if len(bug.Reporting) >= len(cfg.Reporting) {
+			continue
+		}
+		batchKeys = append(batchKeys, keys[i])
+		if len(batchKeys) == batchSize {
+			if err := updateBugReportingBatch(c, cfg, batchKeys); err != nil {
+				return err
+			}
+			batchKeys = nil
+		}
+	}
+	if len(batchKeys) != 0 {
+		if err := updateBugReportingBatch(c, cfg, batchKeys); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func updateBugReportingBatch(c context.Context, cfg *Config, keys []*datastore.Key) error {
+	tx := func(c context.Context) error {
+		bugs := make([]*Bug, len(keys))
+		if err := datastore.GetMulti(c, keys, bugs); err != nil {
+			return err
+		}
+		for _, bug := range bugs {
+			createBugReporting(bug, cfg)
+		}
+		_, err := datastore.PutMulti(c, keys, bugs)
+		return err
+	}
+	err := datastore.RunInTransaction(c, tx, &datastore.TransactionOptions{XG: true})
+	log.Warningf(c, "updated %v bugs: %v", len(keys), err)
+	return err
+}
+
+// Prevent warnings about dead code.
+var (
+	_ = dropNamespace
+	_ = updateBugReporting
+)
diff --git a/dashboard/app/api.go b/dashboard/app/api.go
index 32cab3871..1f4fea5dd 100644
--- a/dashboard/app/api.go
+++ b/dashboard/app/api.go
@@ -988,12 +988,7 @@ func createBugForCrash(c context.Context, ns string, req *dashapi.Crash) (*Bug,
 					FirstTime:  now,
 					LastTime:   now,
 				}
-				for _, rep := range config.Namespaces[ns].Reporting {
-					bug.Reporting = append(bug.Reporting, BugReporting{
-						Name: rep.Name,
-						ID:   bugReportingHash(bugHash, rep.Name),
-					})
-				}
+				createBugReporting(bug, config.Namespaces[ns])
 				if bugKey, err = datastore.Put(c, bugKey, bug); err != nil {
 					return fmt.Errorf("failed to put new bug: %v", err)
 				}
@@ -1018,6 +1013,16 @@ func createBugForCrash(c context.Context, ns string, req *dashapi.Crash) (*Bug,
 	return bug, bugKey, nil
 }
 
+func createBugReporting(bug *Bug, cfg *Config) {
+	for len(bug.Reporting) < len(cfg.Reporting) {
+		rep := &cfg.Reporting[len(bug.Reporting)]
+		bug.Reporting = append(bug.Reporting, BugReporting{
+			Name: rep.Name,
+			ID:   bugReportingHash(bug.keyHash(), rep.Name),
+		})
+	}
+}
+
 func isActiveBug(c context.Context, bug *Bug) (bool, error) {
 	if bug == nil {
 		return false, nil