--- title: "Using Your Existing OpenTelemetry Setup" description: "Learn how to use your existing custom OpenTelemetry setup with Sentry." url: https://docs.sentry.io/platforms/javascript/guides/aws-lambda/opentelemetry/custom-setup/ --- # Using Your Existing OpenTelemetry Setup | Sentry for AWS Lambda Use this guide when you already have a completely custom OpenTelemetry setup or when you intend to add a custom OpenTelemetry setup next to the Sentry SDK. Setting `skipOpenTelemetrySetup: true` disables the Sentry SDK's automatic OpenTelemetry configuration, **requiring** you to perform the setup manually. For example, to ensure errors are correctly associated with their scope, you must add the `SentryContextManager` to your OpenTelemetry setup. You can find details on the required manual setup further down on this page. If you are looking to simply add individual OpenTelemetry instrumentation to your Sentry setup, you should read [Adding Additional OpenTelemetry Instrumentation](https://docs.sentry.io/platforms/javascript/guides/aws-lambda/opentelemetry/using-opentelemetry-apis.md#adding-additional-opentelemetry-instrumentation) instead. To use an existing OpenTelemetry setup, set `skipOpenTelemetrySetup: true` in your `init({})` config, then set up all the components that Sentry needs yourself. Finish by installing `@sentry/opentelemetry` and adding the following: ```javascript const Sentry = require("@sentry/node"); const { SentrySpanProcessor, SentryPropagator, SentrySampler, } = require("@sentry/opentelemetry"); const { NodeTracerProvider } = require("@opentelemetry/sdk-trace-node"); const sentryClient = Sentry.init({ dsn: "___DSN___", skipOpenTelemetrySetup: true, // The SentrySampler will use this to determine which traces to sample tracesSampleRate: 1.0, }); // Note: This could be BasicTracerProvider or any other provider depending on // how you are using the OpenTelemetry SDK const provider = new NodeTracerProvider({ // Ensure the correct subset of traces is sent to Sentry // This also ensures trace propagation works as expected sampler: sentryClient ? new SentrySampler(sentryClient) : undefined, spanProcessors: [ // Ensure spans are correctly linked & sent to Sentry new SentrySpanProcessor(), // Add additional processors here ], }); provider.register({ // Ensure trace propagation works // This relies on the SentrySampler for correct propagation propagator: new SentryPropagator(), // Ensure context & request isolation are correctly managed contextManager: new Sentry.SentryContextManager(), }); // Validate that the setup is correct Sentry.validateOpenTelemetrySetup(); ``` Make sure that all [Required OpenTelemetry Instrumentation](https://docs.sentry.io/platforms/javascript/guides/aws-lambda/opentelemetry/custom-setup.md#required-instrumentation) is set up correctly. Otherwise, the Sentry SDK may not work as expected. ## [Using Sentry for Error Monitoring Only](https://docs.sentry.io/platforms/javascript/guides/aws-lambda/opentelemetry/custom-setup.md#using-sentry-for-error-monitoring-only) If you have a custom OpenTelemetry setup and only want to use Sentry for error monitoring, you can skip adding the `SentrySpanProcessor`. You'll still need to add the `SentryContextManager`, `SentryPropagator`, and `SentrySampler` to your setup even if you don't want to send any tracing data to Sentry. Read on to learn why this is needed. In order for the Sentry SDK to work as expected, and for it to be in sync with OpenTelemetry, we need a few components to be in place. **Components needed for Sentry to work correctly:** * **SentryContextManager**: Ensures that the OpenTelemetry context is in sync with Sentry, for example to correctly isolate data between simultaneous requests. * **SentrySampler**: Ensures that the Sentry `tracesSampleRate` is respected. Even if you don't use Sentry for tracing, you'll still need this in order for trace propagation to work as expected. Read [Using a Custom Sampler](https://docs.sentry.io/platforms/javascript/guides/aws-lambda/opentelemetry/custom-setup.md#using-a-custom-sampler) if you want to use a custom sampler. * **SentryPropagator**: Ensures that trace propagation works correctly. * [Required Instrumentation](https://docs.sentry.io/platforms/javascript/guides/aws-lambda/opentelemetry/custom-setup.md#required-instrumentation): Ensures that trace propagation works correctly. **Additional components needed to also use Sentry for tracing:** * **SentrySpanProcessor**: Ensures that spans are correctly sent to Sentry. Trace propagation is needed for Sentry to automatically connect services together. (For example, if you want to connect the frontend and backend, or different backend services.) This makes it possible to see related errors across services. [Learn more about Trace Propagation.](https://docs.sentry.io/platforms/javascript/guides/aws-lambda/tracing/trace-propagation.md) The following code snippet shows how to set up Sentry for error monitoring only: ```javascript import * as Sentry from "@sentry/node"; import { SentryPropagator, SentrySampler } from "@sentry/opentelemetry"; import { NodeTracerProvider } from "@opentelemetry/sdk-trace-node"; import { BatchSpanProcessor } from "@opentelemetry/sdk-trace-base"; import { OTLPTraceExporter } from "@opentelemetry/exporter-otlp-http"; import { registerInstrumentations } from "@opentelemetry/instrumentation"; const sentryClient = Sentry.init({ dsn: "___DSN___", // Skipping the OpenTelemetry setup automatically disables emitting spans in the httpIntegration with `spans: false` skipOpenTelemetrySetup: true, // Important: We do not define a tracesSampleRate here at all! // This leads to tracing being disabled }); // Create and configure e.g. NodeTracerProvider const provider = new NodeTracerProvider({ // This ensures trace propagation works as expected sampler: sentryClient ? new SentrySampler(sentryClient) : undefined, }); provider.addSpanProcessor( new BatchSpanProcessor( new OTLPTraceExporter({ url: "http://OTLP-ENDPOINT.com/api", }), ), ); // Initialize the provider provider.register({ propagator: new SentryPropagator(), contextManager: new Sentry.SentryContextManager(), }); registerInstrumentations({ instrumentations: [ // Add OTEL instrumentation here ], }); ``` ## [Required Instrumentation](https://docs.sentry.io/platforms/javascript/guides/aws-lambda/opentelemetry/custom-setup.md#required-instrumentation) By default, Sentry will register OpenTelemetry instrumentation to automatically capture spans for traces spanning incoming and outgoing HTTP requests, DB queries, and more. If tracing is not enabled (no `tracesSampleRate` is defined in the SDK configuration), only a minimal amount of OpenTelemetry instrumentation will be registered. This includes the following: * A Sentry-specific HTTP instrumentation that handles request isolation and trace propagation. This can work in parallel with [@opentelemetry/instrumentation-http](https://www.npmjs.com/package/@opentelemetry/instrumentation-http), if you register it. * [nativeNodeFetchIntegration](https://docs.sentry.io/platforms/javascript/guides/aws-lambda/configuration/integrations/nodefetch.md) registers [opentelemetry-instrumentation-fetch-node](https://www.npmjs.com/package/opentelemetry-instrumentation-fetch-node) which is needed for trace propagation. These are needed to make sure that trace propagation works correctly. If you want to add your own http/node-fetch instrumentation, you have to follow the following steps: ### [Custom HTTP Instrumentation](https://docs.sentry.io/platforms/javascript/guides/aws-lambda/opentelemetry/custom-setup.md#custom-http-instrumentation) Available since: `v8.35.0` You can add your own `@opentelemetry/instrumentation-http` instance in your OpenTelemetry setup. However, in this case, you need to disable span creation in Sentry's `httpIntegration`. You can also set `tracePropagation: false` to prevent Sentry from injecting trace headers, letting your OpenTelemetry setup handle propagation instead: ```javascript const sentryClient = Sentry.init({ dsn: "___DSN___", skipOpenTelemetrySetup: true, integrations: [ Sentry.httpIntegration({ spans: false, tracePropagation: false }), ], }); ``` It's important that `httpIntegration` is still registered this way to ensure that the Sentry SDK can correctly isolate requests, for example when capturing errors. ### [Custom Node Fetch Instrumentation](https://docs.sentry.io/platforms/javascript/guides/aws-lambda/opentelemetry/custom-setup.md#custom-node-fetch-instrumentation) If tracing is disabled, the Node Fetch instrumentation will not emit any spans. In this scenario, it will only inject sentry-specific trace propagation headers. You are free to add your own Node Fetch instrumentation on top of this which may emit spans as you like. If your OpenTelemetry setup already handles trace propagation for fetch requests, you can set `tracePropagation: false` to prevent Sentry from injecting duplicate trace headers: ```javascript const sentryClient = Sentry.init({ dsn: "___DSN___", skipOpenTelemetrySetup: true, integrations: [ Sentry.nativeNodeFetchIntegration({ tracePropagation: false }), ], }); ``` ## [Using a Custom Sampler](https://docs.sentry.io/platforms/javascript/guides/aws-lambda/opentelemetry/custom-setup.md#using-a-custom-sampler) While you can use your own sampler, we recommend that you use the `SentrySampler`. This will ensure that the correct subset of traces will be sent to Sentry, based on your `tracesSampleRate`. It will also ensure that all other Sentry features like trace propagation work as expected. If you do need to use your own sampler, make sure to wrap your `SamplingResult` with our `wrapSamplingDecision` method like in the example below: ```javascript import * as Sentry from "@sentry/node"; import { wrapSamplingDecision } from "@sentry/opentelemetry"; import { NodeTracerProvider } from "@opentelemetry/sdk-trace-node"; // implements Sampler from "@opentelemetry/sdk-trace-node" class CustomSampler { shouldSample( context, _traceId, _spanName, _spanKind, attributes, _links, ) { const decision = yourDecisionLogic(); // wrap the result return wrapSamplingDecision({ decision, context, spanAttributes: attributes, }); } toString() { return CustomSampler.name; } } const sentryClient = Sentry.init({ dsn: "___DSN___", skipOpenTelemetrySetup: true, // By defining any sample rate, // tracing integrations will be added by default // omit this if you do not want any performance integrations to be added tracesSampleRate: 0, }); const provider = new NodeTracerProvider({ sampler: new CustomSampler(), }); // ...rest of your setup // Validate that the setup is correct Sentry.validateOpenTelemetrySetup(); ``` ## [ESM Loaders](https://docs.sentry.io/platforms/javascript/guides/aws-lambda/opentelemetry/custom-setup.md#esm-loaders) If your application is running in ESM (`import`/`export` syntax), OpenTelemetry requires you to set up *ESM loader hooks*. The Sentry SDK will automatically register ESM loader hooks by default. However, if you have your own OpenTelemetry setup, it is recommended to configure the Sentry SDK to not register these hooks and instead register them yourself. You can do so by setting `registerEsmLoaderHooks` to `false` and [setting up ESM loader hooks](https://github.com/open-telemetry/opentelemetry-js/blob/main/doc/esm-support.md#instrumentation-hook-required-for-esm): ```javascript Sentry.init({ dsn: "___DSN___", skipOpenTelemetrySetup: true, registerEsmLoaderHooks: false, }); ``` ##### Why is it recommended to register loader hooks yourself? It is recommended registering your own ESM loader hooks when you have a complete custom OpenTelemetry setup, first and foremost because it makes the most sense architecturally. You likely went through the effort to set up OpenTelemetry by itself and now you want to add Sentry to your application without messing with your OpenTelemetry setup. Additionally, there are a few pitfalls that can very simply be avoided by registering your own hooks: * Registering loader hooks multiple times might result in duplicated spans being created. [More details.](https://github.com/getsentry/sentry-javascript/issues/14065#issuecomment-2435546961) * OpenTelemetry instrumentation in ESM is very sensitive as to *when* it is added relative to *when* the loader hooks are registered. The control over this should stay with the owner of the OpenTelemetry setup and not the Sentry SDK.