Unit testing a JAX-RS Web Service?

Question

I'm currently looking for ways to create automated tests for a JAX-RS (Java API for RESTful Web Services) based web service.

I basically need a way to send it certain inputs and verify that I get the expected responses. I'd prefer to do this via JUnit, but I'm not sure how that can be achieved.

What approach do you use to test your web-services?

Update: As entzik pointed out, decoupling the web service from the business logic allows me to unit test the business logic. However, I also want to test for the correct HTTP status codes etc.

Answer 1

You probably wrote some java code that implements your business logic and then you have generated the web services end point for it.

An important thing to do is to independently test your business logic. Since it's pure java code you can do that with regular JUnit tests.

Now, since the web services part is just an end point, what you want to make sure is that the generated plumbing (stubs, etc) are in sync with your java code. you can do that by writing JUnit tests that invoke the generated web service java clients. This will let you know when you change your java signatures without updating the web services stuff.

If your web services plumbing is automatically generated by your build system at every build, then it may not be necessary to test the end points (assuming it's all properly generated). Depends on your level of paranoia.

Answer 2

I use Apache's HTTPClient (http://hc.apache.org/) to call Restful Services. The HTTP Client library allows you to easily perform get, post or whatever other operation you need. If your service uses JAXB for xml binding, you can create a JAXBContext to serialize and deserialize inputs and outputs from the HTTP request.

Answer 3

Jersey comes with a great RESTful client API that makes writing unit tests really easy. See the unit tests in the examples that ship with Jersey. We use this approach to test the REST support in Apache Camel, if you are interested the test cases are here

Answer 4

You can find an example here: http://blog.tmro.net/2009/03/unit-test-jax-rs-using-java-6-and-junit.html Cheers

Answer 5

Though its too late from the date of posting the question, thought this might be useful for others who have a similar question. Jersey comes with a test framework called the Jersey Test Framework which allows you to test your RESTful Web Service, including the response status codes. You can use it to run your tests on lightweight containers like Grizzly, HTTPServer and/or EmbeddedGlassFish. Also, the framework could be used to run your tests on a regular web container like GlassFish or Tomcat.

Answer 6

An important thing to do is to independently test your business logic

I certainly would not assume that the person who wrote the JAX-RS code and is looking to unit test the interface is somehow, for some bizarre, inexplicable reason, oblivious to the notion that he or she can unit testing other parts of the program, including business logic classes. It's hardly helpful to state the obvious and the point was repeatedly made that the responses need to be tested, too.

Both Jersey and RESTEasy have client applications and in the case of RESTEasy you can use the same annoations (even factor out annotated interface and use on the client and server side of your tests).

REST not what this service can do for you; REST what you can do for this service.