You do not require to use proxy methods, you can directly test the APIs. There are several tests for the APIs, tests to check whether the API can afford the load, tests to check the standards of the HTTP being followed, and much more.
Before I dive into the performance testing, if you need to send a request to the REST API and just test it, consider using an API debugging tool, such as
Postman[
^]. Postman will enable you to enter the URLs of the APIs, pass the data or the states, and then communicate. Latest versions of Postman even let you write automation tasks for the APIs, which I yet have not tried or tested.
It is up to you, what you want to do. But however, in the modern time of cloud computing, we can also expect that you will be consuming an online API (
since you do not make a mention of what API you want to test). In which case,
If you own the API: Then you can use any of the runtime testing library or tool and run the tests to check how it performs. Debugging is a separate thing, you can do the debugging internally as well. I am talking about tests, like load testing etc. There are several of tools for that.
For example,
GitHub - alexfernandez/loadtest: Runs a load test on the selected URL. Easy to extend minimally for your own ends.[
^]
Apache JMeter - Apache JMeter™[
^]
You can then test the APIs for these things. It depends on your language/runtime selection.
If you do not own the API: Then chances are that you only need to test your own application, and verify that it does what your business logic requires from it. For example on Azure APIs, you need to use your own keys in order to test the APIs of their services.
In this case, you need to check with the documentation, as to what does the documentation suggests. :-)