@ethanresnick/instrumentation-ioredis

OpenTelemetry ioredis Instrumentation for Node.js

This module provides automatic instrumentation for the ioredis module, which may be loaded using the @opentelemetry/sdk-trace-node package and is included in the @opentelemetry/auto-instrumentations-node bundle.

If total installation size is not constrained, it is recommended to use the @opentelemetry/auto-instrumentations-node bundle with @opentelemetry/sdk-node for the most seamless instrumentation experience.

Compatible with OpenTelemetry JS API and SDK 1.0+.

Installation

npm install --save @opentelemetry/instrumentation-ioredis

Supported Versions

• >=2.0.0 <6

Usage

To load a specific instrumentation (ioredis in this case), specify it in the registerInstrumentations's configuration

const { NodeTracerProvider } = require('@opentelemetry/sdk-trace-node');
const {
  IORedisInstrumentation,
} = require('@opentelemetry/instrumentation-ioredis');
const { registerInstrumentations } = require('@opentelemetry/instrumentation');

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

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

IORedis Instrumentation Options

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

Options	Type	Description
dbStatementSerializer	DbStatementSerializer	IORedis instrumentation will serialize db.statement using the specified function.
requestHook	RedisRequestCustomAttributeFunction (function)	Function for adding custom attributes on db request. Receives params: span, { moduleVersion, cmdName, cmdArgs }
responseHook	RedisResponseCustomAttributeFunction (function)	Function for adding custom attributes on db response
requireParentSpan	boolean	Require parent to create ioredis span, default when unset is true

Custom db.statement Serializer

The instrumentation serializes the command into a Span attribute called db.statement. The standard serialization format attempts to be as informative as possible while avoiding the export of potentially sensitive data. The number of serialized arguments depends on the specific command, see the configuration list in @opentelemetry/redis-common.

It is also possible to define a custom serialization function. The function will receive the command name and arguments and must return a string.

Here is a simple example to serialize the command name skipping arguments:

const { IORedisInstrumentation } = require('@opentelemetry/instrumentation-ioredis');

const ioredisInstrumentation = new IORedisInstrumentation({
  dbStatementSerializer: function (cmdName, cmdArgs) {
    return cmdName;
  },
});

Using requestHook

Instrumentation user can configure a custom "hook" function which will be called on every request with the relevant span and request information. User can then set custom attributes on the span or run any instrumentation-extension logic per request.

Here is a simple example that adds a span attribute of ioredis instrumented version on each request:

const { IORedisInstrumentation } = require('@opentelemetry/instrumentation-ioredis');

const ioredisInstrumentation = new IORedisInstrumentation({
requestHook: function (
    span: Span,
    requestInfo: IORedisRequestHookInformation
  ) {
    if (requestInfo.moduleVersion) {
      span.setAttribute(
        'instrumented_library.version',
        requestInfo.moduleVersion
      );
    }
  }
});

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.