OpenTelemetry Fetch Instrumentation for web

Note: This is an experimental package under active development. New releases may include breaking changes.

This module provides auto instrumentation for web using fetch. (Note: This instrumentation does not instrument Node.js' fetch. See @opentelemetry/instrumentation-undici for that.)

Installation

npm install --save @opentelemetry/instrumentation-fetch

Usage

import {
  ConsoleSpanExporter,
  SimpleSpanProcessor,
  WebTracerProvider,
} from '@opentelemetry/sdk-trace-web';
import { FetchInstrumentation } from '@opentelemetry/instrumentation-fetch';
import { ZoneContextManager } from '@opentelemetry/context-zone';
import { registerInstrumentations } from '@opentelemetry/instrumentation';

const provider = new WebTracerProvider({
  spanProcessors: [new SimpleSpanProcessor(new ConsoleSpanExporter())]
});

provider.register({
  contextManager: new ZoneContextManager(),
});

registerInstrumentations({
  instrumentations: [new FetchInstrumentation()],
});

// or plugin can be also initialised separately and then set the tracer provider or meter provider
const fetchInstrumentation = new FetchInstrumentation();
const provider = new WebTracerProvider({
  spanProcessors: [new SimpleSpanProcessor(new ConsoleSpanExporter())]
});
provider.register({
  contextManager: new ZoneContextManager(),
});
fetchInstrumentation.setTracerProvider(provider);

// and some test

fetch('http://localhost:8090/fetch.js');

Example Screenshots

See examples/tracer-web/fetch for a short example.

Fetch Instrumentation options

Fetch instrumentation plugin has few options available to choose from. You can set the following:

| Options | Type | Description | | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | ------------------------------ | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | applyCustomAttributesOnSpan | FetchCustomAttributeFunction | Function for adding custom attributes | | requestHook | FetchRequestHookFunction | Function for adding custom attributes or headers before the request is handled | | ignoreNetworkEvents | boolean | Disable network events being added as span events (network events are added by default) | | measureRequestSize | boolean | Measure outgoing request length (outgoing request length is not measured by default) |

Semantic Conventions

The instrumentation-fetch versions v0.220.0 and later emit the stable v1.23.0+ semantic conventions.

Span attributes:

| v1.23.0 semconv | Notes | | ---------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | http.request.method | HTTP request method. With v1.23.0 semconv http.request.method_original may also be included. | | url.full | Full HTTP request URL | | server.address and server.port | The hostname and port of the request URL | | http.response.status_code | HTTP response status code | | http.request.body.size | This is only added if measureRequestSize is true. | | error.type | The response status (as a string), if the response status was >=400. |

Useful links

• For more information on OpenTelemetry, visit: https://opentelemetry.io/
• For more about OpenTelemetry JavaScript: https://github.com/open-telemetry/opentelemetry-js
• For help or feedback on this project, join us in GitHub Discussions

License

Apache 2.0 - See LICENSE for more information.