REST-Assured: going deeper

In my previous post I described the basic REST-Assured usage – the lightweight framework for testing RESTful services. Despite the fact that described range of functionalities would be enough in most cases,REST-Assured has a lot more to offer. In this post I would like to bring some more advanced examples of the framework usage.


I recommend you also my other posts about REST-Assured and building microservice’s test automation frameworks:

Object Mapping

Sending request’s body as string is easy and straightforward, but it can be inconvenient in the case of more complex operations on request / response properties. Proven solution for this is a good-known serialization of request/response body to objects. REST-Assured supports object mapping to (and from) JSON and XML. For JSON you need either to have Jackson or Gson in your classpath and for XML you need JAXB. Here is an example of request object serialization using Jackson libary. Our object represents the following class:

If we have either Jackson or Gson in out classpath, we can create new UserDto object, and send it as a body to REST-Assured method:

What happend here is we’re creating new UserDto object, and after passing it to body() method, Jackson/Gson serialize it to following json:

  JSON Schema Validation Main idea behind JSON Schema Validation is to compare response correctness with declared schema. Assume that you have the following response (this example is from my wiremock’s post):

What we want to do is to perform structural validation, comparing your response with schema declared in your project. First things first, we have to add JSON-schema dependency to our project. In case of gradle it whould be:

testCompile group: ‘com.jayway.restassured’, name: ‘json-schema-validator’, version: ‘2.5.0’

Second, declare schema definition in json file. Below you can see simple example for checking presence of response properties and types:

Last thing is to add static import to class, where you want call JsonSchemaValidator methods (obviously you can avoid star import by providing specific method name):

import static com.jayway.restassured.module.jsv.JsonSchemaValidator.*;

After it’s done, you can call JsonSchemaValidator inside your REST-Assured methods:

After calling /user/{id} method, REST-Assured invokes json schema’s matchesJsonSchemaInClasspath() method, witch compares response against schema definition previously declared in project.

Complex Response Validation

Since REST-Assured is written in Groovy, it takes advantage of Groovy’s sytax. One of the coolest thing in groovy is it’s collection API. You can check all the groovy collection’s interface details here. For the REST-Assured part, let’s assume that we have a following response body:

Our task would be to check, if object which price is greater than 18.00 has title equals to “Sabbath Bloody Sabbath”. Let’s see the code for that:

Continue reading

If you want to continue reading and expand your knowledge in area of  REST and microservices, I recommend you these books:

  • Building Microservices – one of the most important books for me, everything you want to know about microservices is here
  • RESTful Web APIs – another great book about REST architecture. Lots of practical knowledge about designing and consuming RESTful APIs


In this short post my goal was to introduce you with some more advanced REST-Assured examples. Of course you can limit your test only to simple flow described in my previous post and that’s perfectly fine, but I strongly encourage you to expand your test with examples from this post. Remember, that those are only few of my favourites, for more – check framework’s documentation.