NodeJS Adapter

The NodeJS adapter tracks errors in your NodeJS application and reports them to the Log Owl service. Precise details help you tracking down and fixing the root cause.

Usage

Install the adapter with npm i --save @logowl/adapter-nodejs or yarn add @logowl/adapter-nodejs.

const logowl = require('@logowl/adapter-nodejs');

Configuration

Require the adapter at the top of your server and pass the configuration to the init function. The following options are available.

Ticket

The ticket is the only mandatory information. Each service has an unique ticket and all events sent with this ticket will be attached to the corresponding service.

const logowl = require('@logowl/adapter-nodejs');
logowl.init({ ticket: '2ATNP1AD70' });

Badges

Badges contain individual information that will be attached to the reported error. A badge must be of type string. The key of the badge can have up to 100 characters while the value can have up to 200 characters. If these limits are exceeded, the event will not be processed.

logowl.init({
ticket: '2ATNP1AD70',
badges: {
cluster: 'EU',
serverId: process.env.SERVER_ID
}
});

Endpoint

Set the endpoint property to connect to your individual Log Owl instance at a given address. Please notice that the endpoint property will be preferred to the instance property.

logowl.init({
endpoint: 'https://logowl.example.com',
ticket: '2ATNP1AD70'
});

Verifying setup

To test if everything works you can just try to execute an undefined function like so.

logowl.init({
instance: 'demo',
ticket: '2ATNP1AD70'
});
test();

Middleware

If you are using Express, you can also add the Log Owl middleware at the end of your routes.

app.use(logowl.errorHandler);

The middleware will send all errors to Log Owl before passing them to the next middleware.

Emit errors manually

You can also emit errors manually by passing an error instance to the emitError method. This is handy for building your own error handling logic.

try {
const result = 10 * number;
} catch (error) {
logowl.emitError(error);
}

On the fly badges

You can also add dynamic badges to a specific error if you want to provide additional information. This can be useful if you, for example, want to identify the user, who is affected by the error.

try {
const result = 10 * number;
} catch (error) {
logowl.emitError(error, { user: req.user.id });
}