Cron jobs are a nice way to automatically run scheduled tasks. The cron service in Linux systems is the typical approach when scheduling commands on the operating system. {{outline}} Testing a Cron Job Recently the certbot from Let’s Encrypt didn’t automatically renew SSL certificates anymore. We used a …

JavaScript has built-in methods to generate a single, random number. You can leverage this feature to create your own method generating a random number in a range between two other numbers. {{outline}} Random Integer Between X and Y (Exclusive Y) Let’s say you want to generate an integer in …

When working with arrays of data, you may need to run an asynchronous operation on each item. The Promise.all() method provides a convenient interface to run a list of promises in parallel, but it has some limitations. Using Promise.all() may overload the available resources, especially when reaching out …

The recent tutorials in this series on JSON web tokens introduced a handful of code changes. For example, you switched the packages creating JWTs from jsonwebtoken to node-jose to support encrypted and nested tokens. A downside of this switch: the JWT-related claims were added jsonwebtoken automatically when creating a new …

Sometimes you need to remove duplicate values from an array in JavaScript. Actually, it’s straightforward in modern JavaScript to quickly create an array of unique values using the Set data structure. {{outline}} JavaScript Array With Unique Values This is a welcoming use-case for the Set data structure. JavaScript introduced …

The recent tutorials in this JSON web token series walked you through the process of encrypted tokens. Creating an encrypted JSON web token has the benefit that nobody can access the content except the holder of the secret key or key pair. In the previous tutorial, you created an encrypted …

You’re naturally in the needs of handy utilities when working with JavaScript handling arrays. Modern JavaScript frameworks —especially the frontend frameworks— abstract most of the DOM interaction. You’re focusing on the actual logic and implement the data handling. When implementing the logic, a handy utility related to JavaScript …

Implementing signatures and encryption for JSON web tokens can be complex due to the cryptographic handling. Up to this point in this tutorial series, you implemented both features on top of existing libraries. A downside of the previous tutorials: when introducing encrypted tokens, you removed the signature of a JWT. …