feat: Configure Prometheus endpoint via Helm chart (#4562)

Signed-off-by: zyzzmohit <mohitray949@gmail.com>

Author: zyzzmohit

backend/cmd/headlamp.go

@@ -97,6 +97,7 @@ const (
 type clientConfig struct {
 	Clusters                []Cluster `json:"clusters"`
 	IsDynamicClusterEnabled bool      `json:"isDynamicClusterEnabled"`
+	PrometheusEndpoint      string    `json:"prometheusEndpoint"`
 }
 
 type OauthConfig struct {
@@ -1749,7 +1750,7 @@ func parseClusterFromKubeConfig(kubeConfigs []string) ([]Cluster, []error) {
 func (c *HeadlampConfig) getConfig(w http.ResponseWriter, r *http.Request) {
 	w.Header().Set("Content-Type", "application/json")
 
-	clientConfig := clientConfig{c.getClusters(), c.EnableDynamicClusters}
+	clientConfig := clientConfig{c.getClusters(), c.EnableDynamicClusters, c.PrometheusEndpoint}
 
 	if err := json.NewEncoder(w).Encode(&clientConfig); err != nil {
 		logger.Log(logger.LevelError, nil, err, "encoding config")

backend/cmd/server.go

@@ -100,6 +100,7 @@ func buildHeadlampCFG(conf *config.Config, kubeConfigStore kubeconfig.ContextSto
 		ProxyURLs:             strings.Split(conf.ProxyURLs, ","),
 		TLSCertPath:           conf.TLSCertPath,
 		TLSKeyPath:            conf.TLSKeyPath,
+		PrometheusEndpoint:    *conf.PrometheusEndpoint,
 	}
 }
 

backend/cmd/stateless.go

@@ -178,7 +178,7 @@ func (c *HeadlampConfig) parseKubeConfig(w http.ResponseWriter, r *http.Request)
 		return
 	}
 
-	clientConfig := clientConfig{contexts, c.EnableDynamicClusters}
+	clientConfig := clientConfig{contexts, c.EnableDynamicClusters, c.PrometheusEndpoint}
 
 	if err := json.NewEncoder(w).Encode(&clientConfig); err != nil {
 		logger.Log(logger.LevelError, nil, err, "encoding config")

backend/pkg/config/config.go

@@ -83,6 +83,7 @@ type Config struct {
 	// TLS config
 	TLSCertPath string `koanf:"tls-cert-path"`
 	TLSKeyPath  string `koanf:"tls-key-path"`
+	PrometheusEndpoint *string `koanf:"prometheus-endpoint"`
 }
 
 func (c *Config) Validate() error {
@@ -434,6 +435,7 @@ func addGeneralFlags(f *flag.FlagSet) {
 	f.Uint("port", defaultPort, "Port to listen from")
 	f.String("proxy-urls", "", "Allow proxy requests to specified URLs")
 	f.Bool("enable-helm", false, "Enable Helm operations")
+	f.String("prometheus-endpoint", "", "Prometheus endpoint for the cluster")
 }
 
 func addOIDCFlags(f *flag.FlagSet) {

charts/headlamp/templates/deployment.yaml

@@ -316,6 +316,9 @@ spec:
             {{- with .Values.config.baseURL }}
             - "-base-url={{ . }}"
             {{- end }}
+            {{- with .Values.config.prometheus.endpoint }}
+            - "-prometheus-endpoint={{ . }}"
+            {{- end }}
             {{- with .Values.config.tlsCertPath }}
             - "-tls-cert-path={{ . }}"
             {{- end }}

charts/headlamp/values.yaml

@@ -36,6 +36,9 @@ config:
   inClusterContextName: "main"
   # -- base url path at which headlamp should run
   baseURL: ""
+  prometheus:
+    # -- Prometheus endpoint for the cluster
+    endpoint: ""
   oidc:
     # Option 1:
     # @param config.oidc.secret - OIDC secret configuration
@@ -159,8 +162,7 @@ podLabels: {}
 hostUsers: true
 
 # -- Headlamp pod's Security Context
-podSecurityContext:
-  {}
+podSecurityContext: {}
   # fsGroup: 2000
 
 # -- Headlamp containers Security Context
@@ -182,7 +184,6 @@ securityContext:
 #     drop:
 #       - ALL
 
-
 service:
   # -- Annotations to add to the service
   annotations: {}
@@ -209,8 +210,7 @@ persistentVolumeClaim:
   # -- Enable Persistent Volume Claim
   enabled: false
   # -- Annotations to add to the persistent volume claim (if enabled)
-  annotations:
-    {}
+  annotations: {}
   # -- accessModes for the persistent volume claim, eg: ReadWriteOnce, ReadOnlyMany, ReadWriteMany etc.
   accessModes: []
   # -- size of the persistent volume claim, eg: 10Gi. Required if enabled is true.
@@ -226,8 +226,7 @@ ingress:
   # -- Enable ingress controller resource
   enabled: false
   # -- Annotations for Ingress resource
-  annotations:
-    {}
+  annotations: {}
     # kubernetes.io/tls-acme: "true"
 
   # -- Additional labels to add to the Ingress resource
@@ -240,8 +239,7 @@ ingress:
 
   # -- Hostname(s) for the Ingress resource
   # Please refer to https://kubernetes.io/docs/reference/kubernetes-api/service-resources/ingress-v1/#IngressSpec for more information.
-  hosts:
-    []
+  hosts: []
     # - host: chart-example.local
     #   paths:
     #   - path: /
@@ -286,8 +284,7 @@ httpRoute:
   #         port: 80
 
 # -- CPU/Memory resource requests/limits
-resources:
-  {}
+resources: {}
   # We usually recommend not to specify default resources and to leave this as a conscious
   # choice for the user. This also increases chances charts run on environments with little
   # resources, such as Minikube. If you do want to specify resources, uncomment the following
@@ -351,8 +348,7 @@ pluginsManager:
   #     cpu: "1000m"
   #     memory: "4096Mi"
   # If omitted, the plugin manager will inherit the global securityContext
-  securityContext:
-    {}
+  securityContext: {}
     # runAsUser: 1001
     # runAsNonRoot: true
     # allowPrivilegeEscalation: false

frontend/src/components/App/Layout.tsx

@@ -32,6 +32,7 @@ import { useCluster, useClustersConf } from '../../lib/k8s';
 import { request } from '../../lib/k8s/api/v1/clusterRequests';
 import { Cluster } from '../../lib/k8s/cluster';
 import { getSavedNamespaces } from '../../lib/storage';
+import { setPluginConfig } from '../../plugin/pluginConfigSlice';
 import { setConfig } from '../../redux/configSlice';
 import { ConfigState } from '../../redux/configSlice';
 import { setNamespaceFilter } from '../../redux/filterSlice';
@@ -178,6 +179,39 @@ const fetchConfig = (dispatch: Dispatch<UnknownAction>) => {
       fetchStatelessClusterKubeConfigs(dispatch);
     }
 
+    if (config?.prometheusEndpoint) {
+      const currentPluginConfigs: { [key: string]: any } = store.getState().pluginConfigs || {};
+      const prometheusConfig = currentPluginConfigs['prometheus'] || {};
+      const newPrometheusConfig: { [key: string]: any } = { ...prometheusConfig };
+      let hasChanges = false;
+
+      Object.keys(clustersToConfig).forEach(clusterName => {
+        const currentClusterConfig = prometheusConfig[clusterName] || {};
+        if (
+          currentClusterConfig.address !== config.prometheusEndpoint ||
+          !currentClusterConfig.isMetricsEnabled ||
+          currentClusterConfig.autoDetect !== false
+        ) {
+          newPrometheusConfig[clusterName] = {
+            ...currentClusterConfig,
+            isMetricsEnabled: true,
+            address: config.prometheusEndpoint,
+            autoDetect: false,
+          };
+          hasChanges = true;
+        }
+      });
+
+      if (hasChanges) {
+        dispatch(
+          setPluginConfig({
+            configKey: 'prometheus',
+            payload: newPrometheusConfig,
+          })
+        );
+      }
+    }
+
     return configToStore;
   });
 };

frontend/src/redux/configSlice.ts

@@ -19,6 +19,7 @@ import { createSlice } from '@reduxjs/toolkit';
 import type { Cluster } from '../lib/k8s/cluster';
 
 export interface ConfigState {
+  prometheusEndpoint?: string;
   /**
    * Clusters is a map of cluster names to cluster objects.
    * Null indicates that the clusters have not been loaded yet.
@@ -89,8 +90,14 @@ const configSlice = createSlice({
      * @param state - The current state.
      * @param action - The payload action containing the config.
      */
-    setConfig(state, action: PayloadAction<{ clusters: ConfigState['clusters'] }>) {
+    setConfig(
+      state,
+      action: PayloadAction<{ clusters: ConfigState['clusters']; prometheusEndpoint?: string }>
+    ) {
       state.clusters = action.payload.clusters;
+      if (action.payload.prometheusEndpoint) {
+        state.prometheusEndpoint = action.payload.prometheusEndpoint;
+      }
     },
     /**
      * Save the config. To both the store, and localStorage.