Cleanup Prometheus detection (#4316)

src/main/prometheus/helm.ts

@@ -29,7 +29,7 @@ export class PrometheusHelm extends PrometheusLens {
   readonly rateAccuracy: string = "5m";
   readonly isConfigurable: boolean = true;
 
-  public async getPrometheusService(client: CoreV1Api): Promise<PrometheusService | undefined> {
-    return this.getFirstNamespacedServer(client, "app=prometheus,component=server,heritage=Helm");
+  public async getPrometheusService(client: CoreV1Api): Promise<PrometheusService> {
+    return this.getFirstNamespacedService(client, "app=prometheus,component=server,heritage=Helm");
   }
 }

src/main/prometheus/lens.ts

@@ -21,7 +21,6 @@
 
 import { PrometheusProvider, PrometheusService } from "./provider-registry";
 import type { CoreV1Api } from "@kubernetes/client-node";
-import logger from "../logger";
 import { inspect } from "util";
 
 export class PrometheusLens extends PrometheusProvider {
@@ -30,22 +29,8 @@ export class PrometheusLens extends PrometheusProvider {
   readonly rateAccuracy: string = "1m";
   readonly isConfigurable: boolean = false;
 
-  public async getPrometheusService(client: CoreV1Api): Promise<PrometheusService | undefined> {
-    try {
-      const resp = await client.readNamespacedService("prometheus", "lens-metrics");
-      const service = resp.body;
-
-      return {
-        id: this.id,
-        namespace: service.metadata.namespace,
-        service: service.metadata.name,
-        port: service.spec.ports[0].port,
-      };
-    } catch(error) {
-      logger.warn(`PrometheusLens: failed to list services: ${error.response.body.message}`);
-
-      return undefined;
-    }
+  public getPrometheusService(client: CoreV1Api): Promise<PrometheusService> {
+    return this.getNamespacedService(client, "prometheus", "lens-metrics");
   }
 
   public getQuery(opts: Record<string, string>, queryName: string): string {

src/main/prometheus/operator.ts

@@ -29,8 +29,8 @@ export class PrometheusOperator extends PrometheusProvider {
   readonly name: string = "Prometheus Operator";
   readonly isConfigurable: boolean = true;
 
-  public async getPrometheusService(client: CoreV1Api): Promise<PrometheusService | undefined> {
-    return this.getFirstNamespacedServer(client, "operated-prometheus=true", "self-monitor=true");
+  public async getPrometheusService(client: CoreV1Api): Promise<PrometheusService> {
+    return this.getFirstNamespacedService(client, "operated-prometheus=true", "self-monitor=true");
   }
 
   public getQuery(opts: Record<string, string>, queryName: string): string {

src/main/prometheus/provider-registry.ts

@@ -20,8 +20,8 @@
  */
 
 import type { CoreV1Api } from "@kubernetes/client-node";
+import { inspect } from "util";
 import { Singleton } from "../../common/utils";
-import logger from "../logger";
 
 export type PrometheusService = {
   id: string;
@@ -43,7 +43,7 @@ export abstract class PrometheusProvider {
     return `sum(rate(nginx_ingress_controller_bytes_sent_sum{ingress="${ingress}",namespace="${namespace}",status=~"${statuses}"}[${this.rateAccuracy}])) by (ingress, namespace)`;
   }
 
-  protected async getFirstNamespacedServer(client: CoreV1Api, ...selectors: string[]): Promise<PrometheusService | undefined> {
+  protected async getFirstNamespacedService(client: CoreV1Api, ...selectors: string[]): Promise<PrometheusService> {
     try {
       for (const selector of selectors) {
         const { body: { items: [service] }} = await client.listServiceForAllNamespaces(null, null, null, selector);
@@ -58,10 +58,26 @@ export abstract class PrometheusProvider {
         }
       }
     } catch (error) {
-      logger.warn(`${this.name}: failed to list services: ${error.toString()}`);
+      throw new Error(`Failed to list services for Prometheus${this.name} in all namespaces: ${error.response.body.message}`);
     }
 
-    return undefined;
+    throw new Error(`No service found for Prometheus${this.name} from any namespace`);
+  }
+
+  protected async getNamespacedService(client: CoreV1Api, name: string, namespace: string): Promise<PrometheusService> {
+    try {
+      const resp = await client.readNamespacedService(name, namespace);
+      const service = resp.body;
+
+      return {
+        id: this.id,
+        namespace: service.metadata.namespace,
+        service: service.metadata.name,
+        port: service.spec.ports[0].port,
+      };
+    } catch(error) {
+      throw new Error(`Failed to list services for Prometheus${this.name} in namespace=${inspect(namespace, false, undefined, false)}: ${error.response.body.message}`);
+    }
   }
 }
 

src/main/prometheus/stacklight.ts

@@ -21,7 +21,6 @@
 
 import { PrometheusProvider, PrometheusService } from "./provider-registry";
 import type { CoreV1Api } from "@kubernetes/client-node";
-import logger from "../logger";
 import { inspect } from "util";
 
 export class PrometheusStacklight extends PrometheusProvider {
@@ -30,22 +29,8 @@ export class PrometheusStacklight extends PrometheusProvider {
   readonly rateAccuracy: string = "1m";
   readonly isConfigurable: boolean = true;
 
-  public async getPrometheusService(client: CoreV1Api): Promise<PrometheusService | undefined> {
-    try {
-      const resp = await client.readNamespacedService("prometheus-server", "stacklight");
-      const service = resp.body;
-
-      return {
-        id: this.id,
-        namespace: service.metadata.namespace,
-        service: service.metadata.name,
-        port: service.spec.ports[0].port,
-      };
-    } catch(error) {
-      logger.warn(`PrometheusLens: failed to list services: ${error.response.body.message}`);
-
-      return undefined;
-    }
+  public getPrometheusService(client: CoreV1Api): Promise<PrometheusService> {
+    return this.getNamespacedService(client, "prometheus-server", "stacklight");
   }
 
   public getQuery(opts: Record<string, string>, queryName: string): string {