use on_error callback in Sources.ResolveDatabases()

Author: pashagolub

internal/cmdopts/cmdsource.go

@@ -99,7 +99,7 @@ func (cmd *SourceResolveCommand) Execute(args []string) error {
 			}
 		}
 	}
-	conns, err := foundSources.ResolveDatabases()
+	conns, err := foundSources.ResolveDatabases(nil)
 	if err != nil {
 		return err
 	}

internal/reaper/reaper.go

@@ -408,19 +408,10 @@ func (r *Reaper) LoadSources(ctx context.Context) (err error) {
 		// filter out disabled sources and sources with group not in the list of groups to monitor
 		return !s.IsEnabled || len(r.Sources.Groups) > 0 && !slices.Contains(r.Sources.Groups, s.Group)
 	})
-	newSrcs, err = srcs.ResolveDatabases()
-	if err != nil {
+
+	if newSrcs, err = srcs.ResolveDatabases(r.WriteInstanceDown); err != nil {
+		// discover dtabases for continuous monitoring sources
 		r.logger.WithError(err).Error("could not resolve databases from sources")
-		for _, s := range srcs {
-			if s.Kind != sources.SourcePostgresContinuous && s.Kind != sources.SourcePatroni {
-				continue
-			}
-			if !slices.ContainsFunc(newSrcs, func(sc *sources.SourceConn) bool {
-				return sc.Name == s.Name || strings.HasPrefix(sc.Name, s.Name+"_")
-			}) {
-				r.WriteInstanceDown(s.Name)
-			}
-		}
 	}
 
 	for i, newMD := range newSrcs {

internal/sources/resolver.go

@@ -28,7 +28,7 @@ import (
 
 // ResolveDatabases() updates list of monitored objects from continuous monitoring sources, e.g. patroni.
 // Each source is resolved concurrently so that a slow or unreachable source does not block the others.
-func (srcs Sources) ResolveDatabases() (_ SourceConns, err error) {
+func (srcs Sources) ResolveDatabases(onError func(string)) (_ SourceConns, err error) {
 	type result struct {
 		dbs SourceConns
 		err error
@@ -45,6 +45,9 @@ func (srcs Sources) ResolveDatabases() (_ SourceConns, err error) {
 	resolvedDbs := make(SourceConns, 0, len(srcs))
 	for i, res := range results {
 		if res.err != nil {
+			if onError != nil {
+				onError(srcs[i].Name)
+			}
 			logger.WithField("source", srcs[i].Name).WithError(res.err).Error("could not resolve databases from source")
 			err = errors.Join(err, res.err)
 		}