DiscoveryConfig Status: update even when no resources are found (#49588…

…) (#50331)

* DiscoveryConfig Status: update even when no resources are found

The DiscoveryService was not updating the DiscoveryConfigStatus when its
matchers didn't discovered any resource.

This would lead the user to think that there the DiscoveryConfig was not
being processed, when in fact it was.

* rename to FilterMapUnique

* rename to DiscoveryConfigName and GetDiscoveryConfigName

* fix var name

lib/srv/discovery/common/interfaces.go

@@ -36,10 +36,10 @@ type Fetcher interface {
 	// IntegrationName identifies the integration name whose credentials were used to fetch the resources.
 	// Might be empty when the fetcher is using ambient credentials.
 	IntegrationName() string
-	// DiscoveryConfigName is the name of the discovery config which originated the resource.
+	// GetDiscoveryConfigName is the name of the discovery config which originated the resource.
 	// Might be empty when the fetcher is using static matchers:
 	// ie teleport.yaml/discovery_service.<cloud>.<matcher>
-	DiscoveryConfigName() string
+	GetDiscoveryConfigName() string
 	// Cloud returns the cloud the fetcher is operating.
 	Cloud() string
 }

lib/srv/discovery/common/watcher.go

@@ -177,9 +177,9 @@ func (w *Watcher) fetchAndSend() {
 				// Add the integration name to the static labels for each resource.
 				fetcherLabels[types.TeleportInternalDiscoveryIntegrationName] = lFetcher.IntegrationName()
 			}
-			if lFetcher.DiscoveryConfigName() != "" {
+			if lFetcher.GetDiscoveryConfigName() != "" {
 				// Add the discovery config name to the static labels of each resource.
-				fetcherLabels[types.TeleportInternalDiscoveryConfigName] = lFetcher.DiscoveryConfigName()
+				fetcherLabels[types.TeleportInternalDiscoveryConfigName] = lFetcher.GetDiscoveryConfigName()
 			}
 
 			if w.cfg.DiscoveryGroup != "" {

lib/srv/discovery/common/watcher_test.go

@@ -178,7 +178,7 @@ func (m *mockFetcher) IntegrationName() string {
 	return ""
 }
 
-func (m *mockFetcher) DiscoveryConfigName() string {
+func (m *mockFetcher) GetDiscoveryConfigName() string {
 	return ""
 }
 func (m *mockFetcher) Cloud() string {

lib/srv/discovery/database_watcher.go

@@ -30,6 +30,7 @@ import (
 	"github.com/gravitational/teleport/lib/services"
 	"github.com/gravitational/teleport/lib/srv/discovery/common"
 	"github.com/gravitational/teleport/lib/utils"
+	"github.com/gravitational/teleport/lib/utils/slices"
 )
 
 const databaseEventPrefix = "db/"
@@ -74,6 +75,14 @@ func (s *Server) startDatabaseWatchers() error {
 			Origin:         types.OriginCloud,
 			Clock:          s.clock,
 			PreFetchHookFn: func() {
+				discoveryConfigs := slices.FilterMapUnique(
+					s.getAllDatabaseFetchers(),
+					func(f common.Fetcher) (s string, include bool) {
+						return f.GetDiscoveryConfigName(), f.GetDiscoveryConfigName() != ""
+					},
+				)
+				s.updateDiscoveryConfigStatus(discoveryConfigs...)
+
 				s.awsRDSResourcesStatus.reset()
 			},
 		},
@@ -99,7 +108,7 @@ func (s *Server) startDatabaseWatchers() error {
 
 					resourceGroup := awsResourceGroupFromLabels(db.GetStaticLabels())
 					resourcesFoundByGroup[resourceGroup] += 1
-					discoveryConfigsChanged[resourceGroup.discoveryConfig] = struct{}{}
+					discoveryConfigsChanged[resourceGroup.discoveryConfigName] = struct{}{}
 
 					dbs = append(dbs, db)
 				}