feat(cloudflare): Allow interop with OpenTelemetry emitted spans

Author: mydea

packages/cloudflare/package.json

@@ -49,7 +49,8 @@
     "access": "public"
   },
   "dependencies": {
-    "@sentry/core": "9.31.0"
+    "@sentry/core": "9.31.0",
+    "@opentelemetry/api": "^1.9.0"
   },
   "peerDependencies": {
     "@cloudflare/workers-types": "^4.x"

packages/cloudflare/src/opentelemetry/tracer.ts

@@ -0,0 +1,69 @@
+import type { Context, Span, SpanOptions, Tracer, TracerProvider } from '@opentelemetry/api';
+import { trace } from '@opentelemetry/api';
+import { startInactiveSpan, startSpan } from '@sentry/core';
+
+/**
+ * Set up a mock OTEL tracer to allow inter-op with OpenTelemetry emitted spans.
+ * This is not perfect but handles easy/common use cases.
+ */
+export function setupOpenTelemetryTracer(): void {
+  trace.setGlobalTracerProvider(new SentryCloudflareTraceProvider());
+}
+
+class SentryCloudflareTraceProvider implements TracerProvider {
+  private readonly _tracers: Map<string, Tracer> = new Map();
+
+  public getTracer(name: string, version?: string, options?: { schemaUrl?: string }): Tracer {
+    const key = `${name}@${version || ''}:${options?.schemaUrl || ''}`;
+    if (!this._tracers.has(key)) {
+      this._tracers.set(key, new SentryCloudflareTracer());
+    }
+
+    // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+    return this._tracers.get(key)!;
+  }
+}
+
+class SentryCloudflareTracer implements Tracer {
+  public startSpan(name: string, options?: SpanOptions): Span {
+    return startInactiveSpan({ name, ...options });
+  }
+
+  /**
+   * NOTE: This does not handle `context` being passed in. It will always put spans on the current scope.
+   */
+  public startActiveSpan<F extends (span: Span) => unknown>(name: string, fn: F): ReturnType<F>;
+  public startActiveSpan<F extends (span: Span) => unknown>(name: string, options: SpanOptions, fn: F): ReturnType<F>;
+  public startActiveSpan<F extends (span: Span) => unknown>(
+    name: string,
+    options: SpanOptions,
+    context: Context,
+    fn: F,
+  ): ReturnType<F>;
+  public startActiveSpan<F extends (span: Span) => unknown>(
+    name: string,
+    options: unknown,
+    context?: unknown,
+    fn?: F,
+  ): ReturnType<F> {
+    const opts = typeof options === 'object' && options !== null ? options : {};
+
+    const spanOpts = {
+      name,
+      ...opts,
+    };
+
+    const callback = (
+      typeof options === 'function'
+        ? options
+        : typeof context === 'function'
+          ? context
+          : typeof fn === 'function'
+            ? fn
+            : // eslint-disable-next-line @typescript-eslint/no-empty-function
+              () => {}
+    ) as F;
+
+    return startSpan(spanOpts, callback) as ReturnType<F>;
+  }
+}

packages/cloudflare/src/sdk.ts

@@ -13,6 +13,7 @@ import {
 import type { CloudflareClientOptions, CloudflareOptions } from './client';
 import { CloudflareClient } from './client';
 import { fetchIntegration } from './integrations/fetch';
+import { setupOpenTelemetryTracer } from './opentelemetry/tracer';
 import { makeCloudflareTransport } from './transport';
 import { defaultStackParser } from './vendor/stacktrace';
 
@@ -50,5 +51,7 @@ export function init(options: CloudflareOptions): CloudflareClient | undefined {
     transport: options.transport || makeCloudflareTransport,
   };
 
+  setupOpenTelemetryTracer();
+
   return initAndBind(CloudflareClient, clientOptions) as CloudflareClient;
 }