Anybody who has worked with me for more than five minutes know that I have two basic categories of test tools that I gravitate toward: proxies and command line tools.
Proxies are great because they give you valuable insight in to the network requests your application is making that aren't usually visible from within the app. Command line tools are great for lots of reasons, mainly because junior developers and less tech savvy people on the team will think you are some sort of super hacker wizard if they walk by and see you frantically typing in a terminal window.
But it's not alwasy obvious how to get your terminal to send network traffic to a proxy.
These days I use Postman as my API test tool of choice. It's a solid tool for testing and includes a commmand line runner (Newman). When using the GUI, it's really easy to see the requests and responses. When running Newman from the command line, not so much.
So how do you configure CLIs to use a local proxy? Turns out you just need to set the
environment variable. And when you're done you can
unset it. (Examples below use the default port for Charles Proxy).