OpenTelemetry Node SDK

[![NPM Published Version][npm-img]][npm-url]
[![Apache License][license-image]][license-image]

This module provides automated instrumentation and tracing for Node.js applications.

For manual instrumentation see the
@opentelemetry/sdk-trace-base package.

Note: Much of OpenTelemetry JS documentation is written assuming the compiled application is run as CommonJS.
For more details on ECMAScript Modules vs CommonJS, refer to esm-support.

How auto instrumentation works

This package exposes a NodeTracerProvider.
For loading instrumentations please use registerInstrumentations function from opentelemetry-instrumentation

OpenTelemetry comes with a growing number of instrumentation plugins for well known modules (see supported modules) and an API to create custom instrumentation (see the instrumentation developer guide).

> Please note: This module does not bundle any plugins. They need to be installed separately.

This is done by wrapping all tracing-relevant functions.

This instrumentation code will automatically

- extract a trace-context identifier from inbound requests to allow distributed tracing (if applicable)
- make sure that this current trace-context is propagated while the transaction traverses an application (see [context document in @opentelemetry/api][def-context] for an in-depth explanation)
- add this trace-context identifier to outbound requests to allow continuing the distributed trace on the next hop (if applicable)
- create and end spans

Creating custom spans on top of auto-instrumentation

Additionally to automated instrumentation, NodeTracerProvider exposes the same API as @opentelemetry/sdk-trace-base, allowing creating custom spans if needed.

Installation

``bash
npm install --save @opentelemetry/api
npm install --save @opentelemetry/sdk-trace-node

Install instrumentation plugins

npm install --save @opentelemetry/instrumentation-http

and for example one additional

npm install --save @opentelemetry/instrumentation-graphql
`

Usage

The following code will configure the NodeTracerProvider to instrument http
(and any other installed supported
modules)
using @opentelemetry/plugin-http.

`javascript
const { registerInstrumentations } = require('@opentelemetry/instrumentation');
const { NodeTracerProvider } = require('@opentelemetry/sdk-trace-node');

// Create and configure NodeTracerProvider
const provider = new NodeTracerProvider();

// Initialize the provider
provider.register();

// register and load instrumentation and old plugins - old plugins will be loaded automatically as previously
// but instrumentations needs to be added
registerInstrumentations({
});

// Your application code - http will automatically be instrumented if
// @opentelemetry/plugin-http is present
const http = require('http');
`

Instrumentation configuration

In the following example:

- the express instrumentation is enabled
- the http instrumentation has a custom config for a requestHook

`javascript
const { registerInstrumentations } = require('@opentelemetry/instrumentation');
const { HttpInstrumentation } = require('@opentelemetry/instrumentation-http');
const { ExpressInstrumentation } = require('@opentelemetry/instrumentation-express');

const provider = new NodeTracerProvider();
provider.register();

// register and load instrumentation and old plugins - old plugins will be loaded automatically as previously
// but instrumentations needs to be added
registerInstrumentations({
instrumentations: [
new ExpressInstrumentation(),
new HttpInstrumentation({
requestHook: (span, request) => {
span.setAttribute("custom request hook attribute", "request");
},
}),
],
});


``

Examples

See how to automatically instrument http and gRPC / grpc-js using node-sdk.

Useful links

- For more information on OpenTelemetry, visit:
- For more about OpenTelemetry JavaScript:
- For help or feedback on this project, join us in [GitHub Discussions][discussions-url]

License

Apache 2.0 - See [LICENSE][license-url] for more information.

[discussions-url]: https://github.com/open-telemetry/opentelemetry-js/discussions
[license-url]: https://github.com/open-telemetry/opentelemetry-js/blob/main/LICENSE
[license-image]: https://img.shields.io/badge/license-Apache_2.0-green.svg?style=flat
[def-context]: https://github.com/open-telemetry/opentelemetry-js/blob/main/doc/context.md
[npm-url]: https://www.npmjs.com/package/@opentelemetry/sdk-trace-node
[npm-img]: https://badge.fury.io/js/%40opentelemetry%2Fsdk-trace-node.svg