Javascript OpenTelemetry Instrumentation

This document contains instructions on how to set up OpenTelemetry instrumentation in your Javascript applications and view your application traces in SigNoz.

npm install --save @opentelemetry/api
npm install --save @opentelemetry/auto-instrumentations-node

export OTEL_TRACES_EXPORTER="otlp"
export OTEL_EXPORTER_OTLP_ENDPOINT="ingest.<region>.signoz.cloud:443"
export OTEL_NODE_RESOURCE_DETECTORS="env,host,os"
export OTEL_SERVICE_NAME="<APP_NAME>"
export OTEL_EXPORTER_OTLP_HEADERS="signoz-ingestion-key=<your-ingestion-key>"
export NODE_OPTIONS="--require @opentelemetry/auto-instrumentations-node/register"
<your_run_command>

npm install --save @opentelemetry/api@^1.6.0
npm install --save @opentelemetry/sdk-node@^0.45.0
npm install --save @opentelemetry/auto-instrumentations-node@^0.39.4
npm install --save @opentelemetry/exporter-trace-otlp-http@^0.45.0

// tracing.js
'use strict'
const process = require('process')
const opentelemetry = require('@opentelemetry/sdk-node')
const { getNodeAutoInstrumentations } = require('@opentelemetry/auto-instrumentations-node')
const { OTLPTraceExporter } = require('@opentelemetry/exporter-trace-otlp-http')
const { Resource } = require('@opentelemetry/resources')
const { SemanticResourceAttributes } = require('@opentelemetry/semantic-conventions')

// do not set headers in exporterOptions, the OTel spec recommends setting headers through ENV variables
// https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/protocol/exporter.md#specifying-headers-via-environment-variables

// highlight-start
const exporterOptions = {
  url: 'https://ingest.<region>.signoz.cloud:443/v1/traces',
}
// highlight-end

const traceExporter = new OTLPTraceExporter(exporterOptions)
const sdk = new opentelemetry.NodeSDK({
  traceExporter,
  instrumentations: [getNodeAutoInstrumentations()],
  resource: new Resource({
    // highlight-next-line
    [SemanticResourceAttributes.SERVICE_NAME]: 'node_app',
  }),
})

// initialize the SDK and register with the OpenTelemetry API
// this enables the API to record telemetry
sdk.start()

// gracefully shut down the SDK on process exit
process.on('SIGTERM', () => {
  sdk
    .shutdown()
    .then(() => console.log('Tracing terminated'))
    .catch((error) => console.log('Error terminating tracing', error))
    .finally(() => process.exit(0))
})

OTEL_EXPORTER_OTLP_HEADERS="signoz-ingestion-key=<your-ingestion-key>" node -r ./tracing.js app.js

npm install --save @opentelemetry/api
npm install --save @opentelemetry/auto-instrumentations-node

export OTEL_TRACES_EXPORTER="otlp"
export OTEL_EXPORTER_OTLP_ENDPOINT="http://localhost:4318/v1/traces"
export OTEL_NODE_RESOURCE_DETECTORS="env,host,os"
export OTEL_SERVICE_NAME="<APP_NAME>"
export NODE_OPTIONS="--require @opentelemetry/auto-instrumentations-node/register"
<your_run_command>

npm install --save @opentelemetry/api@^1.6.0
npm install --save @opentelemetry/sdk-node@^0.45.0
npm install --save @opentelemetry/auto-instrumentations-node@^0.39.4
npm install --save @opentelemetry/exporter-trace-otlp-http@^0.45.0

// tracing.js
'use strict'
const process = require('process')
const opentelemetry = require('@opentelemetry/sdk-node')
const { getNodeAutoInstrumentations } = require('@opentelemetry/auto-instrumentations-node')
const { OTLPTraceExporter } = require('@opentelemetry/exporter-trace-otlp-http')
const { Resource } = require('@opentelemetry/resources')
const { SemanticResourceAttributes } = require('@opentelemetry/semantic-conventions')

const exporterOptions = {
  url: process.env.OTEL_EXPORTER_OTLP_ENDPOINT || 'http://localhost:4318/v1/traces',
}

const traceExporter = new OTLPTraceExporter(exporterOptions)
const sdk = new opentelemetry.NodeSDK({
  traceExporter,
  instrumentations: [getNodeAutoInstrumentations()],
  resource: new Resource({
    // highlight-next-line
    [SemanticResourceAttributes.SERVICE_NAME]: 'node_app',
  }),
})

// initialize the SDK and register with the OpenTelemetry API
// this enables the API to record telemetry
sdk.start()

// gracefully shut down the SDK on process exit
process.on('SIGTERM', () => {
  sdk
    .shutdown()
    .then(() => console.log('Tracing terminated'))
    .catch((error) => console.log('Error terminating tracing', error))
    .finally(() => process.exit(0))
})

node -r ./tracing.js app.js

Validating instrumentation by checking for traces

With your application running, you can verify that you’ve instrumented your application with OpenTelemetry correctly by confirming that tracing data is being reported to SigNoz.

To do this, you need to ensure that your application generates some data. Applications will not produce traces unless they are being interacted with, and OpenTelemetry will often buffer data before sending. So you need to interact with your application and wait for some time to see your tracing data in SigNoz.

Validate your traces in SigNoz:

1. Trigger an action in your app that generates a web request. Hit the endpoint a number of times to generate some data. Then, wait for some time.
2. In SigNoz, open the Services tab. Hit the Refresh button on the top right corner, and your application should appear in the list of Applications.
3. Go to the Traces tab, and apply relevant filters to see your application’s traces.

You might see other dummy applications if you’re using SigNoz for the first time. You can remove it by following the docs here.

If you don't see your application reported in the list of services, try our troubleshooting guide.

Troubleshooting your installation

Set an environment variable to run the OpenTelemetry launcher in debug mode, where it logs details about the configuration and emitted spans:

export OTEL_LOG_LEVEL=debug

The output may be very verbose with some benign errors. Early in the console output, look for logs about the configuration. Next, look for lines like the ones below, which are emitted when spans are emitted to SigNoz.

{
  "traceId": "985b66d592a1299f7d12ebca56ca1fe3",
  "parentId": "8d62a70aa335a227",
  "name": "bar",
  "id": "17ada85c3d55376a",
  "kind": 0,
  "timestamp": 1685674607399000,
  "duration": 299,
  "attributes": {},
  "status": { "code": 0 },
  "events": []
}
{
  "traceId": "985b66d592a1299f7d12ebca56ca1fe3",
  "name": "foo",
  "id": "8d62a70aa335a227",
  "kind": 0,
  "timestamp": 1585130342183948,
  "duration": 315,
  "attributes": {
    "name": "value"
  },
  "status": { "code": 0 },
  "events": [
    {
      "name": "event in foo",
      "time": [1585130342, 184213041]
    }
  ]
}

Running short applications (Lambda/Serverless/etc) If your application exits quickly after startup, you may need to explicitly shutdown the tracer to ensure that all spans are flushed:

opentelemetry.trace.getTracer('your_tracer_name').getActiveSpanProcessor().shutdown()

Sample Javascript App

• We have included a sample applications at:
  • Sample React App Github Repo
  • Sample NodeJs App Github Repo
  • Sample Distributed Tracing NodeJs App Github Repo

Further Reading

• Nodejs Performance Monitoring
• Implementing Distributed Tracing in a Nodejs application

Frequently Asked Questions

1. How to find what to use in IP of SigNoz if I have installed SigNoz in Kubernetes cluster?

   Based on where you have installed your application and where you have installed SigNoz, you need to find the right value for this. Please use this grid to find the value you should use for IP of SigNoz

2. I am sending data from my application to SigNoz, but I don't see any events or graphs in the SigNoz dashboard. What should I do?

   This could be because of one of the following reasons:

   1. Your application is generating telemetry data, but not able to connect with SigNoz installation

      Please use this troubleshooting guide to find if your application is able to access SigNoz installation and send data to it.

   2. Your application is not actually generating telemetry data

      Please check if the application is generating telemetry data first. You can use Console Exporter to just print your telemetry data in console first. Join our Slack Community if you need help on how to export your telemetry data in console

   3. Your SigNoz installation is not running or behind a firewall

      Please double check if the pods in SigNoz installation are running fine. docker ps or kubectl get pods -n platform are your friends for this.

What Cloud Endpoint Should I Use?

The primary method for sending data to SigNoz Cloud is through OTLP exporters. You can either send the data directly from your application using the exporters available in SDKs/language agents or send the data to a collector agent, which batches/enriches telemetry and sends it to the Cloud.

My Collector Sends Data to SigNoz Cloud

Using gRPC Exporter

The endpoint should be ingest.{region}.signoz.cloud:443, where {region} should be replaced with in, us, or eu. Note that the exporter endpoint doesn't require a scheme for the gRPC exporter in the collector.

# Sample config with `us` region
exporters:
    otlp:
        endpoint: "ingest.us.signoz.cloud:443"
        tls:
            insecure: false
        headers:
            "signoz-ingestion-key": "<SIGNOZ_INGESTION_KEY>"

Using HTTP Exporter

The endpoint should be https://ingest.{region}.signoz.cloud:443, where {region} should be replaced with in, us, or eu. Note that the endpoint includes the scheme https for the HTTP exporter in the collector.

# Sample config with `us` region
exporters:
    otlphttp:
        endpoint: "https://ingest.us.signoz.cloud:443"
        tls:
            insecure: false
        headers:
            "signoz-ingestion-key": "<SIGNOZ_INGESTION_KEY>"

My Application Sends Data to SigNoz Cloud

The endpoint should be configured either with environment variables or in the SDK setup code.

Using Environment Variables

Using gRPC Exporter

Examples with us region

• OTEL_EXPORTER_OTLP_PROTOCOL=grpc OTEL_EXPORTER_OTLP_ENDPOINT=https://ingest.us.signoz.cloud:443 OTEL_EXPORTER_OTLP_HEADERS=signoz-ingestion-key=<SIGNOZ_INGESTION_KEY>

Using HTTP Exporter

• OTEL_EXPORTER_OTLP_PROTOCOL=http/protobuf OTEL_EXPORTER_OTLP_ENDPOINT=https://ingest.us.signoz.cloud:443 OTEL_EXPORTER_OTLP_HEADERS=signoz-ingestion-key=<SIGNOZ_INGESTION_KEY>

Configuring Endpoint in Code

Please refer to the agent documentation.

Sending Data from a Third-Party Service

The endpoint configuration here depends on the export protocol supported by the third-party service. They may support either gRPC, HTTP, or both. Generally, you will need to adjust the host and port. The host address should be ingest.{region}.signoz.cloud:443, where {region} should be replaced with in, us, or eu, and port 443 should be used.