Improve handling of the Content-Length header

Previously, some MockMvc-specific logic would add a Content-Length
header to every request that had content. This led to the curl request
snippet containing a -H option for the Content-Length header. This is
unnecessary as curl will automatically generate a Content-Length
header based on the data that's being sent to the server. A secondary
problem was the inconsistent automatic addition of a Content-Length
header; the header was not automatically added to responses.

This commit remove the MockMvc-specific logic in favour of some new
logic in the core project to automatically add a Content-Length header
to both requests and responses. The curl request snippet has been
updated to supress the header in favour of curl's automatic
generation.

Closes gh-111

spring-restdocs-mockmvc/src/test/java/org/springframework/restdocs/mockmvc/MockMvcOperationRequestFactoryTests.java

@@ -157,7 +157,8 @@ public class MockMvcOperationRequestFactoryTests {
 		OperationRequestPart part = request.getParts().iterator().next();
 		assertThat(part.getName(), is(equalTo("file")));
 		assertThat(part.getSubmittedFileName(), is(nullValue()));
-		assertThat(part.getHeaders().isEmpty(), is(true));
+		assertThat(part.getHeaders().size(), is(1));
+		assertThat(part.getHeaders().getContentLength(), is(4L));
 		assertThat(part.getContent(), is(equalTo(new byte[] { 1, 2, 3, 4 })));
 	}
 

spring-restdocs-mockmvc/src/test/java/org/springframework/restdocs/mockmvc/MockMvcRestDocumentationIntegrationTests.java

@@ -79,6 +79,7 @@ import static org.springframework.restdocs.test.SnippetMatchers.codeBlock;
 import static org.springframework.restdocs.test.SnippetMatchers.httpRequest;
 import static org.springframework.restdocs.test.SnippetMatchers.httpResponse;
 import static org.springframework.restdocs.test.SnippetMatchers.snippet;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post;
 import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
 
 /**
@@ -120,6 +121,21 @@ public class MockMvcRestDocumentationIntegrationTests {
 				"http-request.adoc", "http-response.adoc", "curl-request.adoc");
 	}
 
+	@Test
+	public void curlSnippetWithContent() throws Exception {
+		MockMvc mockMvc = MockMvcBuilders.webAppContextSetup(this.context)
+				.apply(documentationConfiguration(this.restDocumentation)).build();
+
+		mockMvc.perform(post("/").accept(MediaType.APPLICATION_JSON).content("content"))
+				.andExpect(status().isOk()).andDo(document("curl-snippet-with-content"));
+		assertThat(new File(
+				"build/generated-snippets/curl-snippet-with-content/curl-request.adoc"),
+				is(snippet().withContents(
+						codeBlock("bash").content(
+								"$ curl " + "'http://localhost:8080/' -i -X POST "
+										+ "-H 'Accept: application/json' -d 'content'"))));
+	}
+
 	@Test
 	public void linksSnippet() throws Exception {
 		MockMvc mockMvc = MockMvcBuilders.webAppContextSetup(this.context)
@@ -298,24 +314,27 @@ public class MockMvcRestDocumentationIntegrationTests {
 								removeHeaders("a"),
 								replacePattern(pattern, "\"<<beta>>\""))));
 
+		String original = "{\"a\":\"alpha\",\"links\":[{\"rel\":\"rel\","
+				+ "\"href\":\"href\"}]}";
 		assertThat(
 				new File("build/generated-snippets/original-response/http-response.adoc"),
 				is(snippet().withContents(
 						httpResponse(HttpStatus.OK)
 								.header("a", "alpha")
 								.header("Content-Type", "application/json")
-								.content(
-										"{\"a\":\"alpha\",\"links\":[{\"rel\":\"rel\","
-												+ "\"href\":\"href\"}]}"))));
+								.header(HttpHeaders.CONTENT_LENGTH,
+										original.getBytes().length).content(original))));
+		String prettyPrinted = String.format("{%n  \"a\" : \"<<beta>>\",%n  \"links\" : "
+				+ "[ {%n    \"rel\" : \"rel\",%n    \"href\" : \"...\"%n  } ]%n}");
 		assertThat(
 				new File(
 						"build/generated-snippets/preprocessed-response/http-response.adoc"),
 				is(snippet().withContents(
-						httpResponse(HttpStatus.OK).header("Content-Type",
-								"application/json").content(
-								String.format("{%n  \"a\" : \"<<beta>>\",%n  \"links\" :"
-										+ " [ {%n    \"rel\" : \"rel\",%n    \"href\" :"
-										+ " \"...\"%n  } ]%n}")))));
+						httpResponse(HttpStatus.OK)
+								.header("Content-Type", "application/json")
+								.header(HttpHeaders.CONTENT_LENGTH,
+										prettyPrinted.getBytes().length)
+								.content(prettyPrinted))));
 	}
 
 	@Test

spring-restdocs-mockmvc/src/test/java/org/springframework/restdocs/mockmvc/RestDocumentationConfigurerTests.java

@@ -27,7 +27,6 @@ import org.springframework.test.web.servlet.request.RequestPostProcessor;
 import org.springframework.web.context.request.RequestContextHolder;
 import org.springframework.web.context.request.ServletRequestAttributes;
 
-import static org.hamcrest.CoreMatchers.equalTo;
 import static org.hamcrest.CoreMatchers.is;
 import static org.hamcrest.CoreMatchers.nullValue;
 import static org.junit.Assert.assertEquals;
@@ -94,17 +93,6 @@ public class RestDocumentationConfigurerTests {
 		assertThat(this.request.getHeader("Content-Length"), is(nullValue()));
 	}
 
-	@Test
-	public void contentLengthHeaderIsSetWhenRequestHasContent() {
-		RequestPostProcessor postProcessor = new RestDocumentationMockMvcConfigurer(
-				this.restDocumentation).beforeMockMvcCreated(null, null);
-		byte[] content = "Hello, world".getBytes();
-		this.request.setContent(content);
-		postProcessor.postProcessRequest(this.request);
-		assertThat(this.request.getHeader("Content-Length"),
-				is(equalTo(Integer.toString(content.length))));
-	}
-
 	private void assertUriConfiguration(String scheme, String host, int port) {
 		assertEquals(scheme, this.request.getScheme());
 		assertEquals(host, this.request.getServerName());