MockMVC in Action!

Marc Nuri

MockMVC

Main entry point for server-side Spring MVC test support
Presentation
- Test pyramid
- The Beer CRUD
- Configuration types
- Aspect oriented / Code coverage
- Examples
  - Spring Boot (1 / 2) - Spring MVC 4 - Web
  - Spring Boot 2 - Spring MVC 5 - Webflux / Project reactor
  - Bonus - Introducing WebTestClient

Pyramid of testing and MockMVC

Pyramid of testing: Unit, Integration, E2E

Beer CRUD

Östia kölsch beer bottle

MockMVC Configuration types

@WebMvcTest annotation

MockMvcBuilders.webAppContextSetup(WebApplicationContext.class);

MockMvcBuilders.standaloneSetup(...);

100% Code Coverage

@PutMapping( path = "/{externalId}", headers = {"Special-Header=XML Babel"}, consumes = MediaType.APPLICATION_JSON_UTF8_VALUE, produces = MediaType.APPLICATION_XML_VALUE) @ResponseStatus(HttpStatus.OK) public Beer updateBeerAsXML( @PathVariable("externalId") String externalId, @Validated @RequestBody Beer beer) { return beerService.updateBeer(externalId, beer); }

@Test public void updateBeerAsXML_validBeer_shouldReturnUpdatedBeer(){ beerResource.updateBeerAsXML("OST.01", new Beer()); verify(mockBeerService, times(1)) .updateBeer(Mockito.eq("OST.01"), Mockito.any(Beer.class)); }

@PutMapping( path = "/{externalId}", headers = {"Special-Header=XML Babel"}, consumes = MediaType.APPLICATION_JSON_UTF8_VALUE, produces = MediaType.APPLICATION_XML_VALUE) @ResponseStatus(HttpStatus.OK) public Beer updateBeerAsXML( @PathVariable("externalId") String externalId, @Validated @RequestBody Beer beer) { return beerService.updateBeer(externalId, beer); }

@PutMapping( path = "/{externalId}", headers = {"Special-Header=XML Babel"}, consumes = MediaType.APPLICATION_JSON_UTF8_VALUE, produces = MediaType.APPLICATION_XML_VALUE) @ResponseStatus(HttpStatus.OK) public Beer updateBeerAsXML( @PathVariable("externalId") String externalId, @Validated @RequestBody Beer beer) { return beerService.updateBeer(externalId, beer); }

Advantages of MockMVC - What can you test

Contract compliance
Content negotiation headers
Response codes
JSON serialization/deserialization
Availability of request/response headers
Validation
Exception handling
Corner cases and configurations

Let's get Reactive

Project Reactor

Q & A

Thank you!

github.com/manusa/presentations-mock-mvc-in-action

@MarcNuri

blog.marcnuri.com