What is @opentelemetry/sdk-node?
The @opentelemetry/sdk-node package is part of the OpenTelemetry project, which aims to provide a set of APIs, libraries, agents, and instrumentation to provide observability for applications. Specifically, the @opentelemetry/sdk-node package is designed for Node.js applications and allows developers to collect traces and metrics, and export them to various observability backends for analysis. This helps in monitoring applications, understanding performance bottlenecks, and troubleshooting issues.
What are @opentelemetry/sdk-node's main functionalities?
Tracing
This feature allows the collection of trace data, which represents the lifecycle of a request through the system. The code sample initializes a tracer provider, sets up a span processor with a Jaeger exporter, and registers the provider. This setup enables the tracing of operations and requests, facilitating the monitoring and debugging of distributed systems.
const { NodeTracerProvider } = require('@opentelemetry/sdk-node');
const { SimpleSpanProcessor } = require('@opentelemetry/tracing');
const { JaegerExporter } = require('@opentelemetry/exporter-jaeger');
const provider = new NodeTracerProvider();
provider.addSpanProcessor(new SimpleSpanProcessor(new JaegerExporter()));
provider.register();
Metrics
This feature enables the collection and export of metrics data, such as counters, gauges, and histograms. The code sample demonstrates how to set up a MeterProvider with a Prometheus exporter, which collects metrics data and makes it available for scraping by Prometheus at a specified port. This is useful for monitoring application performance and resource usage.
const { MeterProvider } = require('@opentelemetry/sdk-node');
const { PrometheusExporter } = require('@opentelemetry/exporter-prometheus');
const meterProvider = new MeterProvider({
exporter: new PrometheusExporter({ port: 9464 }),
interval: 1000
});
meterProvider.start();
Other packages similar to @opentelemetry/sdk-node
jaeger-client
Jaeger-client is a Node.js library for reporting tracing data to Jaeger, a distributed tracing system. While it is focused specifically on integration with Jaeger, @opentelemetry/sdk-node provides a more flexible approach, allowing for the export of traces to multiple backends, not just Jaeger.
prom-client
Prom-client is a Node.js client library for Prometheus metrics. It is similar to the metrics functionality provided by @opentelemetry/sdk-node but is dedicated solely to Prometheus metrics collection and exposition. In contrast, @opentelemetry/sdk-node supports multiple metrics backends and integrates with the broader OpenTelemetry ecosystem for observability.
OpenTelemetry SDK for Node.js
This package provides the full OpenTelemetry SDK for Node.js including tracing and metrics.
Quick Start
To get started you need to install @opentelemetry/sdk-node
, a metrics and/or tracing exporter, and any appropriate plugins for the node modules used by your application.
Installation
$
$ npm install @opentelemetry/sdk-node
$
$ npm install \
@opentelemetry/exporter-jaeger \
@opentelemetry/exporter-prometheus
@opentelemetry/plugin-http
$
$ npm install @opentelemetry/plugins-node-core-and-contrib
Note: this example is for Node.js. See examples/tracer-web for a browser example.
Initialize the SDK
Before any other module in your application is loaded, you must initialize the SDK.
If you fail to initialize the SDK or initialize it too late, no-op implementations will be provided to any library which acquires a tracer or meter from the API.
This example uses Jaeger and Prometheus, but exporters exist for other tracing backends.
const opentelemetry = require("@opentelemetry/sdk-node");
const { JaegerExporter } = require("@opentelemetry/exporter-jaeger");
const { PrometheusExporter } = require("@opentelemetry/exporter-prometheus");
const jaegerExporter = new JaegerExporter({
serviceName: 'my-service',
});
const prometheusExporter = new PrometheusExporter({ startServer: true });
const sdk = new opentelemetry.NodeSDK({
traceExporter: jaegerExporter,
metricExporter: prometheusExporter,
});
sdk
.start()
.then(() => {
})
const process = require("process");
process.on("SIGTERM", () => {
sdk.shutdown()
.then(
() => console.log("SDK shut down successfully"),
(err) => console.log("Error shutting down SDK", err),
)
.finally(() => process.exit(0))
});
Configuration
Below is a full list of configuration options which may be passed into the NodeSDK
constructor;
autoDetectResources
Detect resources automatically from the environment using the default resource detectors. Default true
.
contextManager
Use a custom context manager. Default: AsyncHooksContextManager
textMapPropagator
Use a custom propagator. Default: CompositePropagator using W3C Trace Context and Baggage
metricProcessor
Use a custom processor for metrics. Default: UngroupedProcessor
metricExporter
Configure a metric exporter. If an exporter is not configured, the metrics SDK will not be initialized and registered.
metricInterval
Configure an interval for metrics export in ms. Default: 60,000 (60 seconds)
plugins
Configure plugins. By default, all plugins which are installed and in the Default Plugins List will be enabled.
resource
Configure a resource. Resources may also be detected by using the autoDetectResources
method of the SDK.
sampler
Configure a custom sampler. By default all traces will be sampled.
spanProcessor
traceExporter
Configure a trace exporter. If an exporter OR span processor is not configured, the tracing SDK will not be initialized and registered. If an exporter is configured, it will be used with a BatchSpanProcessor.
traceParams
Configure tracing parameters. These are the same trace parameters used to configure a tracer.
Useful links
License
Apache 2.0 - See LICENSE for more information.