How to use VndErrorJsonRenderer in grails unit test - unit-testing

Question

I'm writing controller unit tests and I'd like to test json result when creation fails.
How can I register VndErrorJsonRenderer in unit test ? I tried simply defineBeans in setup() but it doesn't work :(
import com.vividsolutions.jts.geom.Coordinate
import grails.transaction.Transactional
import org.codehaus.groovy.grails.web.servlet.mvc.GrailsParameterMap
import static org.springframework.http.HttpStatus.CREATED
import static org.springframework.http.HttpStatus.NO_CONTENT
#Transactional(readOnly = true)
class UserController {
static namespace = "v1"
static allowedMethods = [profile: 'GET', create: "POST", update: "PUT", delete: "DELETE"]
static responseFormats = ['json', 'vnd.error+json']
def springSecurityService
def geometryFactory
/**
* Saves a resource
*/
#Transactional
def create() {
User instance = createResource(params)
instance.validate()
if (instance.hasErrors()) {
respond instance.errors, view: 'create' // STATUS CODE 422
return
}
instance.save flush: true
respond instance, [status: CREATED]
}
protected User createResource(GrailsParameterMap params) {
Double x = params.double("location.x", 0)
Double y = params.double("location.y", 0)
User user = new User()
bindData(user, params, [include: ['username', 'password', 'profile.*']])
if (x > 0 && y > 0)
user.location = geometryFactory.createPoint(new Coordinate(x, y))
else
user.location = null
user.roles = []
user.roles.add(Role.findByAuthority(Role.ROLE_USER))
return user
}
}
And my test :
#Before
void setup() {
defineBeans {
vndJsonErrorRenderer(VndErrorJsonRenderer)
}
}
void "Test the create action with a non unique username"() {
User.metaClass.encodePassword = {
"aaa"
}
// Create first user
assertNotNull getValidUser().save(flush: true)
when: "The create action is executed with a username already used"
def user = getValidUser()
controller.request.addHeader("Accept", "application/vnd.error+json,application/json")
controller.request.contentType = "application/json"
controller.request.content = JsonMapperUtil.mapAsJson(user)?.getBytes()
controller.create()
then: "The response status is UNPROCESSABLE_ENTITY and the username unique error is returned"
println response.text
response.status == UNPROCESSABLE_ENTITY.value
def json = JSON.parse(response.text)
assertNull "VND format not returned", json.errors
}
I'm using grails 2.3.6 with restful controller.
Thanks

Answer 1

In the case you are showing where you depend on respond it would be best to test this more as an integration test so all components that may interact with respond are all wired for you.
In a unit test for what ever beans are needed in the class under test I find it easiest to directly set them on the class under test.