Initial Commit

packages/communication/emails/delivery-tracking/tests/setup/polyfills.ts

@@ -0,0 +1,36 @@
+/**
+ * Test setup for `@suaveplan/delivery-tracking`.
+ *
+ * Installs a real in-memory OpenTelemetry `MeterProvider` BEFORE any
+ * source module imports — `metrics.getMeter()` therefore binds to this
+ * provider, so `flushTestMetrics()` returns the exact counter snapshots
+ * the production code emitted.
+ */
+import { metrics } from "@opentelemetry/api";
+import {
+    AggregationTemporality,
+    InMemoryMetricExporter,
+    MeterProvider,
+    PeriodicExportingMetricReader,
+} from "@opentelemetry/sdk-metrics";
+
+export const testInMemoryMetricExporter = new InMemoryMetricExporter(
+    AggregationTemporality.DELTA
+);
+
+const reader = new PeriodicExportingMetricReader({
+    exporter: testInMemoryMetricExporter,
+    exportIntervalMillis: 60_000,
+});
+
+export const testMeterProvider = new MeterProvider({ readers: [reader] });
+metrics.setGlobalMeterProvider(testMeterProvider);
+
+export async function flushTestMetrics(): Promise<
+    ReturnType<typeof testInMemoryMetricExporter.getMetrics>
+> {
+    await testMeterProvider.forceFlush();
+    const collected = testInMemoryMetricExporter.getMetrics();
+    testInMemoryMetricExporter.reset();
+    return collected;
+}