With dozens of microservices running on multiple production regions, getting to a point where any error log can be immediately identified and resolved feels like a distant dream. As an observability company, we at Coralogix are pedantic when it comes to any issue in one of our environments. That’s why we are using an internal Coralogix account to monitor our development and production environments.

Nest.js is a scalable and efficient server-side Node.js framework built with TypeScript. Nest.js was created to provide a structural design pattern to the Node.js development world. It was inspired by Angular.js and uses Express.js under the hood. Nest.js is compatible with the majority of Express.js middleware. In this tutorial, I will lead you through building a RESTful API with Nest.js. The tutorial will familiarize you with the fundamental principles and building blocks of Nest.js.

Maintaining an endpoint, especially a customer-facing one, requires constant monitoring, whether using REST or GraphQL. As the industry has looked for solutions to build a more adaptive endpoint technology, it is also a must to monitor these endpoints. GraphQL and REST are two different technologies that allow user-facing clients to link to databases and platform logic. Both GraphQL and REST include monitoring techniques.

gRPC is a remote procedure call framework that has been widely adopted among cloud native applications. It is an attractive choice for engineers needing more capabilities than what REST APIs provide. However, observability and testing tools for gRPC are few and far between. Because of this, triaging or understanding application behavior is potentially time-consuming and overly burdensome.

Modern-day applications aim to cover a wide range of users’ needs in a flexible and scalable manner. The software development landscape is moving at a fast pace, and the competition is so fierce that a business simply can’t afford to offer a low-quality product. Thorough testing of both functional and non-functional aspects of a software application has become an essential step in the software development process. It ensures that users get the best version of your product.

In this blog post we’ll help answer the age old question, “What does this service talk to and what does it say?” We’ll see how to inspect inbound and outbound REST API calls to see what calls are being made and what incoming traffic causes a reaction. This can be pretty handy when you’re taking over maintenance of an existing service, or if your code just isn’t behaving the way you expect.

We've found a pattern to mock external client libraries while keeping code simple, reducing the number of injection spots and ensuring all the code down a callstack uses the same mock client. Establishing patterns like these is what makes test suites great, and improves developer productivity when writing tests. Here's how it works.