[Cloud Connect] Use Display Name to register cluster (#47440)

This overrides the cluster name submitted to the Cloud Connected
API with the `cluster.metadata.display_name` setting -- if set --
with the proper precendence of transient, then persistent setting.

For any existing registration, this will overwrite the old name
with the new name upon restart.

Author: pickypg

changelog/fragments/1762213574-cc-cluster-name.yaml

@@ -0,0 +1,19 @@
+# REQUIRED
+# - bug-fix: fixes a problem in a previous version
+kind: bug-fix
+summary: "[Cloud Connect] Use cluster.metadata.display_name as cluster name if set"
+component: metricbeat
+
+# AUTOMATED
+# OPTIONAL to manually add other PR URLs
+# PR URL: A link the PR that added the changeset.
+# If not present is automatically filled by the tooling finding the PR where this changelog fragment has been added.
+# NOTE: the tooling supports backports, so it's able to fill the original PR number instead of the backport PR number.
+# Please provide it if you are adding a fragment for a different PR.
+# pr: https://github.com/owner/repo/1234
+
+# AUTOMATED
+# OPTIONAL to manually add other issue URLs
+# Issue URL; optional; the GitHub issue related to this changeset (either closes or is part of).
+# If not present is automatically filled by the tooling with the issue linked to the PR number.
+# issue: https://github.com/owner/repo/1234

x-pack/metricbeat/module/autoops_es/metricset/register.go

@@ -18,10 +18,25 @@ import (
 )
 
 const (
-	licensePath   = "/_license"
-	licensePathV7 = "/_license?accept_enterprise"
+	clusterSettingsPath = "/_cluster/settings?filter_path=**.cluster.metadata.display_name"
+	licensePath         = "/_license"
+	licensePathV7       = "/_license?accept_enterprise"
 )
 
+type clusterSettingsResponse struct {
+	Persistent clusterSettingsDisplayName `json:"persistent"`
+	Transient  clusterSettingsDisplayName `json:"transient"`
+}
+
+// Partial structure to extract the cluster display name from the cluster settings API response.
+type clusterSettingsDisplayName struct {
+	Cluster struct {
+		Metadata struct {
+			DisplayName string `json:"display_name"`
+		} `json:"metadata"`
+	} `json:"cluster"`
+}
+
 // License information returned from `GET /_license`, contained within the "license" object.
 type license struct {
 	UID    string `json:"uid"`
@@ -75,20 +90,38 @@ func maybeRegisterCloudConnectedCluster(m *elasticsearch.MetricSet, getClusterIn
 	cloudApiKey, err := getCloudConnectedModeApiKey(m)
 
 	if err != nil {
-		return fmt.Errorf("failed to get Cloud Connected Mode API key: %w", err)
+		return fmt.Errorf("failed to get Cloud Connected API Key: %w", err)
 	} else if cloudApiKey == "" {
 		// if there is no Cloud API Key configured, then there is no request to make
 		return nil
 	}
 
-	m.Logger().Debugf("Attempting to get cluster info for Cloud Connected Mode...")
+	m.Logger().Debugf("Attempting to get cluster info for Cloud Connected...")
 	clusterInfo, err := getClusterInfo(m)
 
 	if err != nil {
 		return fmt.Errorf("failed to load cluster info: %w", err)
 	}
 
-	m.Logger().Debugf("Attempting to fetch license for Cloud Connected Mode...")
+	m.Logger().Debugf("Attempting to fetch cluster settings for Cloud Connected...")
+	clusterSettings, err := utils.FetchAPIData[clusterSettingsResponse](m, clusterSettingsPath)
+
+	if err != nil {
+		// Log the error, but do not fail the registration - we can continue with the existing cluster name
+		// Note: You can restart the agent to re-fetch the name later if needed
+		m.Logger().Warnf("Ignoring failure to fetch cluster settings for Cloud Connected: %v", err)
+		// prefer transient setting over persistent setting
+	} else if clusterSettings.Transient.Cluster.Metadata.DisplayName != "" {
+		m.Logger().Debugf("Using transient cluster display name %s for Cloud Connected in place of cluster name %s", clusterSettings.Transient.Cluster.Metadata.DisplayName, clusterInfo.ClusterName)
+
+		clusterInfo.ClusterName = clusterSettings.Transient.Cluster.Metadata.DisplayName
+	} else if clusterSettings.Persistent.Cluster.Metadata.DisplayName != "" {
+		m.Logger().Debugf("Using persistent cluster display name %s for Cloud Connected in place of cluster name %s", clusterSettings.Persistent.Cluster.Metadata.DisplayName, clusterInfo.ClusterName)
+
+		clusterInfo.ClusterName = clusterSettings.Persistent.Cluster.Metadata.DisplayName
+	}
+
+	m.Logger().Debugf("Attempting to fetch license for Cloud Connected...")
 	versionedLicensePath := licensePath
 
 	// TODO: Drop support for this when we drop support for 7.17
@@ -107,7 +140,7 @@ func maybeRegisterCloudConnectedCluster(m *elasticsearch.MetricSet, getClusterIn
 		return fmt.Errorf("cluster license type is not supported: %s", licenseWrapper.License.Type)
 	}
 
-	m.Logger().Debugf("Successfully fetched license for Cloud Connected Mode: UUID=%s License=%s", clusterInfo.ClusterID, licenseWrapper.License.UID)
+	m.Logger().Debugf("Successfully fetched license for Cloud Connected: UUID=%s License=%s", clusterInfo.ClusterID, licenseWrapper.License.UID)
 
 	return registerCloudConnectedCluster(cloudApiKey, clusterInfo, &licenseWrapper.License, m.Logger())
 }
@@ -128,14 +161,14 @@ func registerCloudConnectedCluster(cloudApiKey string, clusterInfo *utils.Cluste
 	})
 
 	if err != nil {
-		return fmt.Errorf("failed to serialize payload for Cloud Connected Mode: %w", err)
+		return fmt.Errorf("failed to serialize payload for Cloud Connected: %w", err)
 	}
 
 	requestURL := getCloudConnectedModeAPIURL() + "/api/v1/cloud-connected/clusters"
 	req, err := http.NewRequestWithContext(context.Background(), "POST", requestURL, bytes.NewBuffer(jsonData))
 
 	if err != nil {
-		return fmt.Errorf("failed to create HTTP request for Cloud Connected Mode: %w", err)
+		return fmt.Errorf("failed to create HTTP request for Cloud Connected: %w", err)
 	}
 
 	req.Header.Set("Accept", "application/json")
@@ -146,9 +179,9 @@ func registerCloudConnectedCluster(cloudApiKey string, clusterInfo *utils.Cluste
 
 	if err == nil {
 		utils.SetResourceID(data.ID)
-		logger.Infof("Registered cluster %s for Cloud Connected Mode: %s", clusterInfo.ClusterID, data.ID)
+		logger.Infof("Registered cluster %s for Cloud Connected: %s", clusterInfo.ClusterID, data.ID)
 		return nil
 	}
 
-	return fmt.Errorf("failed to register for Cloud Connected Mode: %w", err)
+	return fmt.Errorf("failed to register for Cloud Connected: %w", err)
 }