@azure/core-tracing

What is @azure/core-tracing?

The @azure/core-tracing package provides a common interface for adding tracing to Azure SDKs. It allows developers to collect detailed information about operations performed by Azure SDKs, making it easier to diagnose issues and optimize performance. The package is built on OpenTelemetry, a set of APIs, libraries, agents, and instrumentation that provide observability for applications.

What are @azure/core-tracing's main functionalities?

Creating and managing spans

This feature allows developers to create and manage spans, which represent individual operations. Spans can be nested to represent complex operations composed of multiple steps. The code sample demonstrates how to create a tracing client, start a new span, and then end the span.

const { createTracingClient } = require('@azure/core-tracing');
const tracingClient = createTracingClient({
  namespace: 'Microsoft.Azure',
  packageName: 'AzureExample',
  packageVersion: '1.0.0'
});

// Start a new span
cost span = tracingClient.startSpan('myOperation');

// End the span
span.end();

Integrating with Azure SDKs

This feature demonstrates how to integrate the @azure/core-tracing package with other Azure SDKs, such as Azure Storage Blobs. By passing a tracing client to the SDK's client constructor, developers can automatically collect tracing information for operations performed by the SDK.

const { DefaultAzureCredential } = require('@azure/identity');
const { BlobServiceClient } = require('@azure/storage-blob');
const { createTracingClient } = require('@azure/core-tracing');

const tracingClient = createTracingClient({
  namespace: 'Microsoft.Azure',
  packageName: 'Azure.Storage.Blobs',
  packageVersion: '12.0.0'
});

const blobServiceClient = new BlobServiceClient(
  'https://<my-storage-account>.blob.core.windows.net/',
  new DefaultAzureCredential(),
  {
    tracingOptions: { tracingClient }
  }
);

Other packages similar to @azure/core-tracing

jaeger-client

Jaeger client is a distributed tracing system that can be used to monitor and troubleshoot transactions in complex distributed systems. While it provides similar functionality to @azure/core-tracing in terms of tracing operations, Jaeger is a standalone system with its own backend and UI for visualizing traces, making it more suited for end-to-end tracing across multiple services and platforms.

README

Azure Core tracing library for JavaScript

This is the core tracing library that provides low-level interfaces and helper methods for tracing in Azure SDK JavaScript libraries which work in the browser and Node.js.

Getting started

Installation

Install this library using npm as follows

npm install @azure/core-tracing

Key Concepts

The @azure/core-tracing package supports enabling tracing for Azure SDK packages, using an OpenTelemetry Tracer. If you are using OpenCensus instead, we provide an OpenCensusTracerWrapper that allows you to convert an OpenCensus Tracer into an OpenTelemetry Tracer.

By default, all libraries log with a NoOpTracer that takes no action. To change this, you have to use setTracer to set a new default Tracer.

Examples

Example 1 - Setting an OpenTelemetry Tracer

const opentelemetry = require("@opentelemetry/core");
const { BasicTracer, SimpleSpanProcessor } = require("@opentelemetry/tracing");
const { ZipkinExporter } = require("@opentelemetry/exporter-zipkin");
const { setTracer } = require("@azure/core-tracing");

const exporter = new ZipkinExporter({
  serviceName: "azure-tracing-sample"
});
const tracer = new BasicTracer();
tracer.addSpanProcessor(new SimpleSpanProcessor(exporter));

opentelemetry.initGlobalTracer(tracer);

const rootSpan = opentelemetry.getTracer().startSpan("root");

// Call some client library methods and pass rootSpan via tracingOptions.

rootSpan.end();
exporter.shutdown();

Example 2 - Setting an OpenCensus Tracer

const tracing = require("@opencensus/nodejs");
const { ZipkinTraceExporter } = require("@opencensus/exporter-zipkin");
const {
  setTracer,
  OpenCensusTracerWrapper,
  OpenCensusSpanWrapper
} = require("@azure/core-tracing");

const tracer = tracing.start({ samplingRate: 1 }).tracer;

tracer.registerSpanEventListener(
  new ZipkinTraceExporter({
    serviceName: "azure-tracing-sample",
    bufferTimeout: 2
  })
);
setTracer(new OpenCensusTracerWrapper(tracer));
tracer.startRootSpan({ name: "root" }, async (rootSpanEx) => {
  const rootSpan = new OpenCensusSpanWrapper(rootSpanEx);
  // Call some client library methods and pass rootSpan via tracingOptions.
  rootSpanEx.end(); // rootSpan.end() should work as well
});

Example 3 - Passing parent Spans to library operations

// Given a BlobClient from @azure/storage-blob
const result = await blobClient.download(undefined, undefined, {
  tracingOptions: {
    spanOptions: { parent: rootSpan }
  }
});

Contributing

If you'd like to contribute to this library, please read the contributing guide to learn more about how to build and test the code.