OpenTelemetry socket.io Instrumentation for Node.js


This module provides automatic instrumentation for socket.io.

Installation

``
npm install --save opentelemetry-instrumentation-socket.io
`

Usage

For further automatic instrumentation instruction see the @opentelemetry/instrumentation package.

`js
const { NodeTracerProvider } = require('@opentelemetry/sdk-trace-node');
const { registerInstrumentations } = require('@opentelemetry/instrumentation');
const { SocketIoInstrumentation } = require('opentelemetry-instrumentation-socket.io');

registerInstrumentations({
tracerProvider,
instrumentations: [
new SocketIoInstrumentation({
// see under for available configuration
})
]
});
`

$3

socket.io instrumentation has few options available to choose from. You can set the following:

| Options | Type | Description |
| -------------- | -------------------------------------- | ----------------------------------------------------------------------------------------------- |
| emitHook | SocketIoHookFunction | hook for adding custom attributes before socket.io emits the event |
| emitIgnoreEventList | string[] | names of emitted events to ignore tracing for |
| onHook | SocketIoHookFunction | hook for adding custom attributes before the event listener (callback) is invoked |
| onIgnoreEventList | string[] | names of listened events to ignore tracing for |
| traceReserved | boolean | set to true if you want to trace socket.io reserved events (see https://socket.io/docs/v4/emit-cheatsheet/#Reserved-events) |
| filterHttpTransport| HttpTransportInstrumentationConfig | set if you want to filter out the HTTP traces when using HTTP polling as the transport (see below)

#### HttpTransportInstrumentationConfig
If you use opentelemetry-instrumentation-socket.io alongside instrumentation-http, socket.io might use HTTP polling as the transport method. Therefore, you will see an HTTP span created as the parent of the socket.io span.
To filter out those spans; we use HttpTransportInstrumentationConfig.

HttpTransportInstrumentationConfig has a few options available to choose from. You can set the following:

| Options | Type | Description |
| -------------- | -------------------------------------- | ----------------------------------------------------------------------------------------------- |
| httpInstrumentation| HttpInstrumentation | the instance of HttpInstrumentation you pass to registerInstrumentations|
| socketPath | string | the socket.io endpoint path (defaults to /socket.io/`) |
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This extension (and many others) was developed by Aspecto with ❤️