Let’s start by setting up error reporting in React. To do so, we’ll be using Sentry. Sentry is a great service for reporting and debugging errors. And it comes with a very generous free tier.

In this chapter we’ll sign up for a free Sentry account and configure it in our React app. And in the coming chapters we’ll be reporting the various frontend errors to it.

Let’s get started.

Create a Sentry Account

Head over to Sentry and hit Get Started.

Sentry landing page

Then enter your info and hit Create Your Account.

Sentry create an account

Next hit Create project.

Sentry hit create project

For the type of project, select React.

Sentry select React project

Give your project a name.

Sentry name React project

And that’s it. Scroll down and copy the Sentry.init line.

Sentry init code snippet

Install Sentry

Change indicator Now head over to the React frontend/ directory and install Sentry.

$  pnpm add @sentry/react --save

We are going to be using Sentry across our app. So it makes sense to keep all the Sentry related code in one place.

Change indicator Add the following to the top of your src/lib/errorLib.ts.

import * as Sentry from "@sentry/react";
import config from "../config";

export interface ErrorInfoType {
  [key: string | symbol]: string;

const isLocal = process.env.NODE_ENV === "development";

export function initSentry() {
  if (isLocal) {

  Sentry.init({ dsn: config.SENTRY_DSN });

export function logError(error: unknown, errorInfo: ErrorInfoType | null = null) {
  if (isLocal) {

  Sentry.withScope((scope) => {
    errorInfo && scope.setExtras(errorInfo);

Change indicator Add the SENTRY_DSN below the const config = { line in frontend/src/config.ts.

SENTRY_DSN: "https://your-dsn-id-here@sentry.io/123456",

Make sure to replace https://your-dsn-id-here@sentry.io/123456 with the line we copied from the Sentry dashboard above.

We are using the isLocal flag to conditionally enable Sentry because we don’t want to report errors when we are developing locally. Even though we all know that we rarely ever make mistakes while developing…

The logError method is what we are going to call when we want to report an error to Sentry. It takes:

  • An Error object in error.
  • And, an object with key-value pairs of additional info in errorInfo.

Next, let’s initialize our app with Sentry.

Change indicator Add the following to the end of the imports in src/index.tsx.

import { initSentry } from "./lib/errorLib";


Now we are ready to start reporting errors in our React app! Let’s start with the API errors.