Moved the prometheus metrics port from an env variable to the collected powersync config

Author: Rentacookie

modules/module-mongodb/test/src/env.ts

@@ -7,5 +7,5 @@ export const env = utils.collectEnvironmentVariables({
   CI: utils.type.boolean.default('false'),
   SLOW_TESTS: utils.type.boolean.default('false'),
   TEST_MONGO_STORAGE: utils.type.boolean.default('true'),
-  TEST_POSTGRES_STORAGE: utils.type.boolean.default('false')
+  TEST_POSTGRES_STORAGE: utils.type.boolean.default('true')
 });

packages/service-core/src/metrics/open-telemetry/util.ts

@@ -1,11 +1,11 @@
 import { MeterProvider, MetricReader, PeriodicExportingMetricReader } from '@opentelemetry/sdk-metrics';
-import { env } from '../../util/env.js';
 import { PrometheusExporter } from '@opentelemetry/exporter-prometheus';
 import { OTLPMetricExporter } from '@opentelemetry/exporter-metrics-otlp-http';
 import { Resource } from '@opentelemetry/resources';
 import { ServiceContext } from '../../system/ServiceContext.js';
 import { OpenTelemetryMetricsFactory } from './OpenTelemetryMetricsFactory.js';
 import { MetricsFactory } from '../metrics-interfaces.js';
+import { logger } from '@powersync/lib-services-framework';
 
 export interface RuntimeMetadata {
   [key: string]: string | number | undefined;
@@ -15,12 +15,18 @@ export function createOpenTelemetryMetricsFactory(context: ServiceContext): Metr
   const { configuration, lifeCycleEngine, storageEngine } = context;
   const configuredExporters: MetricReader[] = [];
 
-  if (env.METRICS_PORT) {
-    const prometheusExporter = new PrometheusExporter({ port: env.METRICS_PORT, preventServerStart: true });
+  if (configuration.telemetry.prometheus_port) {
+    const prometheusExporter = new PrometheusExporter({
+      port: configuration.telemetry.prometheus_port,
+      preventServerStart: true
+    });
     configuredExporters.push(prometheusExporter);
 
     lifeCycleEngine.withLifecycle(prometheusExporter, {
-      start: () => prometheusExporter.startServer()
+      start: async () => {
+        await prometheusExporter.startServer();
+        logger.info(`Prometheus metric export enabled on port:${configuration.telemetry.prometheus_port}`);
+      }
     });
   }
 

packages/service-core/src/util/config/compound-config-collector.ts

@@ -154,6 +154,7 @@ export class CompoundConfigCollector {
       metadata: baseConfig.metadata ?? {},
       migrations: baseConfig.migrations,
       telemetry: {
+        prometheus_port: baseConfig.telemetry?.prometheus_port,
         disable_telemetry_sharing: baseConfig.telemetry?.disable_telemetry_sharing ?? false,
         internal_service_endpoint:
           baseConfig.telemetry?.internal_service_endpoint ?? 'https://pulse.journeyapps.com/v1/metrics'

packages/service-core/src/util/config/types.ts

@@ -55,6 +55,7 @@ export type ResolvedPowerSyncConfig = {
   };
 
   telemetry: {
+    prometheus_port?: number;
     disable_telemetry_sharing: boolean;
     internal_service_endpoint: string;
   };

packages/service-core/src/util/env.ts

@@ -19,10 +19,6 @@ export const env = utils.collectEnvironmentVariables({
    * Runner to be started in this process
    */
   PS_RUNNER_TYPE: utils.type.string.default(ServiceRunner.UNIFIED),
-  /**
-   * Port for metrics
-   */
-  METRICS_PORT: utils.type.number.optional(),
 
   NODE_ENV: utils.type.string.optional()
 });

packages/types/src/config/PowerSyncConfig.ts

@@ -104,7 +104,7 @@ export type StrictJwk = t.Decoded<typeof jwk>;
 
 export const BaseStorageConfig = t.object({
   type: t.string,
-  // Maximum number of conncetions to the storage database, per process.
+  // Maximum number of connections to the storage database, per process.
   // Defaults to 8.
   max_pool_size: t.number.optional()
 });
@@ -200,6 +200,8 @@ export const powerSyncConfig = t.object({
 
   telemetry: t
     .object({
+      // When set, metrics will be available on this port for scraping by Prometheus.
+      prometheus_port: portCodec.optional(),
       disable_telemetry_sharing: t.boolean,
       internal_service_endpoint: t.string.optional()
     })