WebTestClient throws IllegalArgumentException for invalid Parameters [SPR-17363]

[spring-projects-issues]

Peter Luttrell opened SPR-17363 and commented

Experienced with Spring 5.1.0 RELEASE that is included with SpringBoot 2.1.0.M4.

With the following controller: 

@RestController
class SimpleController {

  @PostMapping(
      path = "/test",
      params = "p",
      consumes = MediaType.APPLICATION_JSON_UTF8_VALUE
  )
  Mono<Simple> test(@RequestBody Simple simple) {
    return Mono.just(simple);
  }

  @Data
  @NoArgsConstructor
  @AllArgsConstructor
  private static class Simple {
    private Long num;
  }

}

And the following tests:

@ExtendWith({RestDocumentationExtension.class, SpringExtension.class})
@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)
@AutoConfigureWebTestClient
class DocTests {

  @Autowired
  protected WebTestClient webTestClient;

  @BeforeEach
  void setUp(ApplicationContext applicationContext, RestDocumentationContextProvider restDocumentation) {
    this.webTestClient = WebTestClient.bindToApplicationContext(applicationContext)
        .configureClient()
        .filter(documentationConfiguration(restDocumentation))
        .build();
  }

  private static final String BODY = "{\"num\":123}";

  @Test
  void springErrorGenerator() {
    webTestClient.post()
        .uri("/test")
        .contentType(MediaType.APPLICATION_JSON_UTF8)
        .syncBody(BODY)
        .exchange()
        .expectStatus().isBadRequest()
        .expectHeader().contentType(MediaType.APPLICATION_JSON_UTF8)
        .expectBody()
        .consumeWith(document("spring-error"));
  }

  @Test
  void demonstrateOk() {
    webTestClient.post()
        .uri(uriBuilder -> uriBuilder.path("/test").queryParam("p", "test").build())
        .contentType(MediaType.APPLICATION_JSON_UTF8)
        .syncBody(BODY)
        .exchange()
        .expectStatus().isOk();
  }

}

I'm experiencing the following exception:

java.lang.IllegalArgumentException: Request body incomplete.java.lang.IllegalArgumentException: Request body incomplete.
 at org.springframework.util.Assert.isTrue(Assert.java:118) at org.springframework.test.web.reactive.server.ExchangeResult.getRequestBodyContent(ExchangeResult.java:149) at org.springframework.restdocs.webtestclient.WebTestClientRequestConverter.convert(WebTestClientRequestConverter.java:73) at org.springframework.restdocs.webtestclient.WebTestClientRequestConverter.convert(WebTestClientRequestConverter.java:60) at org.springframework.restdocs.generate.RestDocumentationGenerator.handle(RestDocumentationGenerator.java:199) at org.springframework.restdocs.webtestclient.WebTestClientRestDocumentation.lambda$document$0(WebTestClientRestDocumentation.java:81) at org.springframework.test.web.reactive.server.DefaultWebTestClient$DefaultBodyContentSpec.lambda$consumeWith$3(DefaultWebTestClient.java:540) at org.springframework.test.web.reactive.server.ExchangeResult.assertWithDiagnostics(ExchangeResult.java:194) at org.springframework.test.web.reactive.server.DefaultWebTestClient$DefaultBodyContentSpec.consumeWith(DefaultWebTestClient.java:540) at example.DocTests.springErrorGenerator(DocTests.java:50) at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.base/java.lang.reflect.Method.invoke(Method.java:566) at org.junit.platform.commons.util.ReflectionUtils.invokeMethod(ReflectionUtils.java:515) at org.junit.jupiter.engine.execution.ExecutableInvoker.invoke(ExecutableInvoker.java:115) at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$invokeTestMethod$6(TestMethodTestDescriptor.java:171) at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:72) at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.invokeTestMethod(TestMethodTestDescriptor.java:167) at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:114) at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:59) at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:105) at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:72) at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:95) at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:71) at java.base/java.util.ArrayList.forEach(ArrayList.java:1540) at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38) at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:110) at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:72) at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:95) at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:71) at java.base/java.util.ArrayList.forEach(ArrayList.java:1540) at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38) at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:110) at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:72) at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:95) at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:71) at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.submit(SameThreadHierarchicalTestExecutorService.java:32) at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor.execute(HierarchicalTestExecutor.java:57) at org.junit.platform.engine.support.hierarchical.HierarchicalTestEngine.execute(HierarchicalTestEngine.java:51) at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:220) at org.junit.platform.launcher.core.DefaultLauncher.lambda$execute$6(DefaultLauncher.java:188) at org.junit.platform.launcher.core.DefaultLauncher.withInterceptedStreams(DefaultLauncher.java:202) at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:181) at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:128) at com.intellij.junit5.JUnit5IdeaTestRunner.startRunnerWithArgs(JUnit5IdeaTestRunner.java:74) at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47) at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242) at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)

Note that with request body is the same for both and is valid. The 'springErrorGenerator' test generates the error. Note that with this test, I am attempting to capture using Spring Rest Docs the Spring response body when the required URL parameter is missing, such as can be displayed by making a test call such as this: 

$ echo '{"num":2}' | http POST localhost:8080/test
HTTP/1.1 400 Bad Request
Content-Length: 175
Content-Type: application/json;charset=UTF-8

{
    "error": "Bad Request",
    "message": "Unsatisfied query parameter conditions: [[p]], actual parameters: {}",
    "path": "/test",
    "status": 400,
    "timestamp": "2018-10-11T07:11:47.206+0000"
}

 

 

---

Affects: 5.1 GA

Referenced from: commits 8df0bc8, c567e65

[spring-projects-issues]

Rossen Stoyanchev commented

This is an issue indeed since the test uses a mock server request connected directly to the client-side request body Flux, and the 400 occurs before the request body is read.