Mono repo -> Master (#22553)

Combines the following repositories into one:

https://github.com/mattermost/mattermost-server
https://github.com/mattermost/mattermost-webapp
https://github.com/mattermost/focalboard
https://github.com/mattermost/mattermost-plugin-playbooks

server/channels/app/platform/cluster_discovery.go

@@ -0,0 +1,77 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package platform
+
+import (
+	"time"
+
+	"github.com/mattermost/mattermost-server/v6/model"
+	"github.com/mattermost/mattermost-server/v6/server/platform/shared/mlog"
+)
+
+const (
+	DiscoveryServiceWritePing = 60 * time.Second
+)
+
+type ClusterDiscoveryService struct {
+	model.ClusterDiscovery
+	platform *PlatformService
+	stop     chan bool
+}
+
+func (cds *ClusterDiscoveryService) Start() {
+	err := cds.platform.Store.ClusterDiscovery().Cleanup()
+	if err != nil {
+		mlog.Warn("ClusterDiscoveryService failed to cleanup the outdated cluster discovery information", mlog.Err(err))
+	}
+
+	exists, err := cds.platform.Store.ClusterDiscovery().Exists(&cds.ClusterDiscovery)
+	if err != nil {
+		mlog.Warn("ClusterDiscoveryService failed to check if row exists", mlog.String("ClusterDiscoveryID", cds.ClusterDiscovery.Id), mlog.Err(err))
+	} else if exists {
+		if _, err := cds.platform.Store.ClusterDiscovery().Delete(&cds.ClusterDiscovery); err != nil {
+			mlog.Warn("ClusterDiscoveryService failed to start clean", mlog.String("ClusterDiscoveryID", cds.ClusterDiscovery.Id), mlog.Err(err))
+		}
+	}
+
+	if err := cds.platform.Store.ClusterDiscovery().Save(&cds.ClusterDiscovery); err != nil {
+		mlog.Error("ClusterDiscoveryService failed to save", mlog.String("ClusterDiscoveryID", cds.ClusterDiscovery.Id), mlog.Err(err))
+		return
+	}
+
+	go func() {
+		mlog.Debug("ClusterDiscoveryService ping writer started", mlog.String("ClusterDiscoveryID", cds.ClusterDiscovery.Id))
+		ticker := time.NewTicker(DiscoveryServiceWritePing)
+		defer func() {
+			ticker.Stop()
+			if _, err := cds.platform.Store.ClusterDiscovery().Delete(&cds.ClusterDiscovery); err != nil {
+				mlog.Warn("ClusterDiscoveryService failed to cleanup", mlog.String("ClusterDiscoveryID", cds.ClusterDiscovery.Id), mlog.Err(err))
+			}
+			mlog.Debug("ClusterDiscoveryService ping writer stopped", mlog.String("ClusterDiscoveryID", cds.ClusterDiscovery.Id))
+		}()
+
+		for {
+			select {
+			case <-ticker.C:
+				if err := cds.platform.Store.ClusterDiscovery().SetLastPingAt(&cds.ClusterDiscovery); err != nil {
+					mlog.Error("ClusterDiscoveryService failed to write ping", mlog.String("ClusterDiscoveryID", cds.ClusterDiscovery.Id), mlog.Err(err))
+				}
+			case <-cds.stop:
+				return
+			}
+		}
+	}()
+}
+
+func (cds *ClusterDiscoveryService) Stop() {
+	cds.stop <- true
+}
+
+func (ps *PlatformService) GetClusterId() string {
+	if ps.Cluster() == nil {
+		return ""
+	}
+
+	return ps.Cluster().GetClusterId()
+}