Test-Driving JavaScript Applications

Design the Database Connection

The app.js file will call a connect function to set the database connection on application start. The rest of the code may call a get function to get the connection. The close function will help to close the database connection. The application may not have a use for the close function during normal execution—the connection is created on start-up and is kept throughout the execution. However, we’ll still design this function because it will be needed to ensure the connections in the connection pool are closed properly during testing. Let’s design those functions, test first, starting with the get function. In the test list, the first test says the get function will return null by default. Let’s write the ...