Express in different environments
In a software release process, we designate systems for development, UAT, staging, production, and so on for different stages of product release. Technically, these contexts of application execution are called environments.
It is very common that we want our software to execute differently on different environments. For example, in a development environment, we would like to see a very verbose detail about any error our software might encounter, but we might not want to do so in the production environment. Express has a very simple mechanism to let us do that. Let's find out how it works.
Express' app.get('env') method returns the current environment of the app. Based on this value, you can configure your app to use different middlewares, Node modules, and so on; effectively changing the behavior of the app based on the environment.
Before we go about configuring our app based on its environment, let's find out how app.get('env') works.
When an Express app starts...
