In this guide we will see how you can catch errors and send them to the Application Monitoring / Error Tracking Software you want.
::: tip
In this example we will use [Sentry](https://sentry.io).
:::
## Create a middleware
A [middleware](../concepts/middlewares.md) will be used in order to catch the errors which will then be sent to Sentry.
- Create a `./middlewares/sentry/index.js` file.
**Path —** `./middlewares/sentry/index.js`
```js
module.exports = strapi => {
return {
initialize() {
strapi.app.use(async (ctx, next) => {
await next();
});
},
};
};
```
## Handle errors
Here is the [Node.js client documentation](https://docs.sentry.io/platforms/node/).
Install it with `yarn add @sentry/node` or `npm install @sentry/node --save`.
- Now add the logic that will catch errors.
**Path —** `./middlewares/sentry/index.js`
```js
const Sentry = require('@sentry/node');
Sentry.init({
dsn: 'https://<key>@sentry.io/<project>',
environment: strapi.config.environment,
});
module.exports = strapi => {
return {
initialize() {
strapi.app.use(async (ctx, next) => {
try {
await next();
} catch (error) {
Sentry.captureException(error);
throw error;
}
});
},
};
};
```
::: warning
It's important to call `throw(error);` to avoid stopping the middleware stack. If you don't re-throw the error, it won't be handled by the Strapi's error formatter and the api will never respond to the client.
To ensure that your middleware catches all errors including those in other middleware, it needs to be added at the beginning of the stack but after the `boom` middleware.
After, the sentry middleware captures and rethrows the error, boom will return an appropriate HTTP response to the client.
