[Feature] Enable additional metrics endpoints

.changeset/dull-bananas-reflect.md

@@ -0,0 +1,7 @@
+---
+'@powersync/service-core': minor
+'@powersync/service-types': minor
+'@powersync/service-image': minor
+---
+
+Added the ability to specify additional metrics export endpoints.

packages/service-core/src/metrics/Metrics.ts

@@ -8,11 +8,13 @@ import * as storage from '../storage/storage-index.js';
 import { CorePowerSyncSystem } from '../system/CorePowerSyncSystem.js';
 import { Resource } from '@opentelemetry/resources';
 import { logger } from '@powersync/lib-services-framework';
+import { configFile } from '@powersync/service-types';
 
 export interface MetricsOptions {
   disable_telemetry_sharing: boolean;
   powersync_instance_id: string;
   internal_metrics_endpoint: string;
+  additional_endpoints?: configFile.AdditionalMetricsEndpoint[];
 }
 
 export class Metrics {
@@ -175,6 +177,19 @@ Anonymous telemetry is currently: ${options.disable_telemetry_sharing ? 'disable
       configuredExporters.push(periodicExporter);
     }
 
+    // Create extra exporters for any additionally configured metric endpoints
+    for (const endpoint of options.additional_endpoints ?? []) {
+      logger.info(`Exporting metrics to endpoint: ${endpoint}`);
+      const additionalEndpointExporter = new PeriodicExportingMetricReader({
+        exporter: new OTLPMetricExporter({
+          url: endpoint.url
+        }),
+        exportIntervalMillis: endpoint.export_interval_ms ?? 1000 * 60 * 5 // 5 Minutes
+      });
+
+      configuredExporters.push(additionalEndpointExporter);
+    }
+
     const meterProvider = new MeterProvider({
       resource: new Resource({
         ['service']: 'PowerSync',

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

@@ -122,7 +122,8 @@ export class CompoundConfigCollector {
       telemetry: {
         disable_telemetry_sharing: baseConfig.telemetry?.disable_telemetry_sharing ?? false,
         internal_service_endpoint:
-          baseConfig.telemetry?.internal_service_endpoint ?? 'https://pulse.journeyapps.com/v1/metrics'
+          baseConfig.telemetry?.internal_service_endpoint ?? 'https://pulse.journeyapps.com/v1/metrics',
+        additional_endpoints: baseConfig?.telemetry?.additional_endpoints
       },
       slot_name_prefix: connections[0]?.slot_name_prefix ?? 'powersync_'
     };

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

@@ -59,6 +59,7 @@ export type ResolvedPowerSyncConfig = {
   telemetry: {
     disable_telemetry_sharing: boolean;
     internal_service_endpoint: string;
+    additional_endpoints?: configFile.AdditionalMetricsEndpoint[];
   };
 
   /** Prefix for postgres replication slot names. May eventually be connection-specific. */

packages/types/src/config/PowerSyncConfig.ts

@@ -92,6 +92,16 @@ export const storageConfig = t.object({
 
 export type StorageConfig = t.Decoded<typeof storageConfig>;
 
+/**
+ * An additional OTLP metrics endpoint
+ */
+export const AdditionalMetricsEndpoint = t.object({
+  url: t.string,
+  export_interval_ms: t.number.optional()
+});
+
+export type AdditionalMetricsEndpoint = t.Decoded<typeof AdditionalMetricsEndpoint>;
+
 export const powerSyncConfig = t.object({
   replication: t
     .object({
@@ -145,7 +155,8 @@ export const powerSyncConfig = t.object({
   telemetry: t
     .object({
       disable_telemetry_sharing: t.boolean,
-      internal_service_endpoint: t.string.optional()
+      internal_service_endpoint: t.string.optional(),
+      additional_endpoints: t.array(AdditionalMetricsEndpoint).optional()
     })
     .optional()
 });

service/src/system/PowerSyncSystem.ts

@@ -44,7 +44,8 @@ export class PowerSyncSystem extends system.CorePowerSyncSystem {
         await Metrics.initialise({
           powersync_instance_id: instanceId,
           disable_telemetry_sharing: config.telemetry.disable_telemetry_sharing,
-          internal_metrics_endpoint: config.telemetry.internal_service_endpoint
+          internal_metrics_endpoint: config.telemetry.internal_service_endpoint,
+          additional_endpoints: config.telemetry.additional_endpoints
         });
       },
       async stop() {