Node.js error tracking installation

Install the PostHog Node SDK using the package manager of your choice:

npm install posthog-node --save

In your app, set your project API key before making any calls.

import { PostHog } from 'posthog-node'

const client = new PostHog(
    '<ph_project_api_key>',
    { host: 'https://us.i.posthog.com' }
)

await client.shutdown() 

You can find your project API key and instance address in the project settings page in PostHog.

Note: As a rule of thumb, we do not recommend hardcoding API keys. Setting it as an environment variable is preferred.

Before proceeding, confirm that you can capture events with PostHog using client.capture('test_event').

Note: A minimum SDK version of v4.5.2 is required, but we recommend keeping up to date with the latest version to ensure you have all of error tracking's features.

You can enable exception autocapture when initializing the PostHog client to automatically capture uncaught exceptions and unhandled rejections in your Node app.

import { PostHog } from 'posthog-node'

const client = new PostHog(
    '<ph_project_api_key>',
    { host: 'https://us.i.posthog.com', enableExceptionAutocapture: true }
)

If you are using the Express framework, you will need to import and call setupExpressErrorHandler with your PostHog client and Express app. This is because Express handles uncaught exceptions internally meaning exception autocapture will not work by default.

import express from 'express'
import { PostHog, setupExpressErrorHandler } from 'posthog-node'

const app = express()
const posthog = new PostHog(PH_API_KEY)

setupExpressErrorHandler(posthog, app)

Note: Error tracking requires access the file system to process stack traces. Some providers, like Cloudflare Workers, do not support Node.js runtime APIs by default and need to be included as per their documentation.

If you need to manually capture exceptions, you can do so by calling the captureException method:

posthog.captureException(e, 'user_distinct_id', additionalProperties)

This is helpful if you've built your own error handling logic or want to capture exceptions normally handled by the framework.

Before proceeding, let's make sure exception events are being captured and sent to PostHog. You should see events appear in the activity feed.

Great, you're capturing exceptions! If you serve minified bundles, the next step is to upload source maps to generate accurate stack traces.

Let's continue to the next section.