I use curl in my tests for the Apache httpd server. I like end-to-end testing and curl is not only the most common HTTP client outside of browsers, it is also very versatile. Since https is now used for everything, tests should use that too. This blog describes how to do a setup for that and how to use curl in this case, so that a full TLS validation is done and all is pretty close to what the usage in a production setup would be.