Update HTTP request and response snippets to honour charset of content

Closes gh-126

spring-restdocs-core/src/main/java/org/springframework/restdocs/http/HttpRequestSnippet.java

@@ -16,6 +16,7 @@
 
 package org.springframework.restdocs.http;
 
+import java.io.IOException;
 import java.io.PrintWriter;
 import java.io.StringWriter;
 import java.util.ArrayList;
@@ -30,6 +31,7 @@ import org.springframework.http.MediaType;
 import org.springframework.restdocs.operation.Operation;
 import org.springframework.restdocs.operation.OperationRequest;
 import org.springframework.restdocs.operation.OperationRequestPart;
+import org.springframework.restdocs.snippet.ModelCreationException;
 import org.springframework.restdocs.snippet.Snippet;
 import org.springframework.restdocs.snippet.TemplatedSnippet;
 import org.springframework.util.StringUtils;
@@ -107,8 +109,7 @@ public class HttpRequestSnippet extends TemplatedSnippet {
 		StringWriter httpRequest = new StringWriter();
 		PrintWriter writer = new PrintWriter(httpRequest);
 		if (request.getContent().length > 0) {
-			writer.println();
-			writer.print(new String(request.getContent()));
+			writer.print(requestBody(request));
 		}
 		else if (isPutOrPost(request)) {
 			if (request.getParts().isEmpty()) {
@@ -125,6 +126,16 @@ public class HttpRequestSnippet extends TemplatedSnippet {
 		return httpRequest.toString();
 	}
 
+	private String requestBody(OperationRequest request) {
+		try {
+			String content = request.getContentAsString();
+			return content.isEmpty() ? content : String.format("%n%s", content);
+		}
+		catch (IOException e) {
+			throw new ModelCreationException("Failed to create response body.", e);
+		}
+	}
+
 	private boolean isPutOrPost(OperationRequest request) {
 		return HttpMethod.PUT.equals(request.getMethod())
 				|| HttpMethod.POST.equals(request.getMethod());

spring-restdocs-core/src/main/java/org/springframework/restdocs/http/HttpResponseSnippet.java

@@ -16,6 +16,7 @@
 
 package org.springframework.restdocs.http;
 
+import java.io.IOException;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
@@ -25,6 +26,7 @@ import java.util.Map.Entry;
 import org.springframework.http.HttpStatus;
 import org.springframework.restdocs.operation.Operation;
 import org.springframework.restdocs.operation.OperationResponse;
+import org.springframework.restdocs.snippet.ModelCreationException;
 import org.springframework.restdocs.snippet.Snippet;
 import org.springframework.restdocs.snippet.TemplatedSnippet;
 
@@ -59,16 +61,23 @@ public class HttpResponseSnippet extends TemplatedSnippet {
 		OperationResponse response = operation.getResponse();
 		HttpStatus status = response.getStatus();
 		Map<String, Object> model = new HashMap<String, Object>();
-		model.put(
-				"responseBody",
-				response.getContent().length > 0 ? String.format("%n%s", new String(
-						response.getContent())) : "");
+		model.put("responseBody", responseBody(response));
 		model.put("statusCode", status.value());
 		model.put("statusReason", status.getReasonPhrase());
 		model.put("headers", headers(response));
 		return model;
 	}
 
+	private String responseBody(OperationResponse response) {
+		try {
+			String content = response.getContentAsString();
+			return content.isEmpty() ? content : String.format("%n%s", content);
+		}
+		catch (IOException e) {
+			throw new ModelCreationException("Failed to create response body.", e);
+		}
+	}
+
 	private List<Map<String, String>> headers(OperationResponse response) {
 		List<Map<String, String>> headers = new ArrayList<>();
 		for (Entry<String, List<String>> header : response.getHeaders().entrySet()) {

spring-restdocs-core/src/main/java/org/springframework/restdocs/operation/OperationRequest.java

@@ -16,6 +16,7 @@
 
 package org.springframework.restdocs.operation;
 
+import java.io.IOException;
 import java.net.URI;
 import java.util.Collection;
 
@@ -38,6 +39,14 @@ public interface OperationRequest {
 	 */
 	byte[] getContent();
 
+	/**
+	 * Returns the contents as string of the request. If the request has no content an empty string
+	 * is returned
+	 * @return the contents as string, never {@code null}
+	 * @throws IOException if an input or output exception occurred
+	 */
+	String getContentAsString() throws IOException;
+
 	/**
 	 * Returns the headers that were included in the request.
 	 *

spring-restdocs-core/src/main/java/org/springframework/restdocs/operation/OperationResponse.java

@@ -16,6 +16,8 @@
 
 package org.springframework.restdocs.operation;
 
+import java.io.IOException;
+
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.HttpStatus;
 
@@ -49,4 +51,12 @@ public interface OperationResponse {
 	 * @return the contents, never {@code null}
 	 */
 	byte[] getContent();
+
+	/**
+	 * Returns the contents as string of the response. If the response has no content an empty string
+	 * is returned
+	 * @return the contents as string, never {@code null}
+	 * @throws IOException if an input or output exception occurred
+	 */
+	String getContentAsString() throws IOException;
 }

spring-restdocs-core/src/main/java/org/springframework/restdocs/operation/StandardOperationRequest.java

@@ -16,6 +16,7 @@
 
 package org.springframework.restdocs.operation;
 
+import java.io.UnsupportedEncodingException;
 import java.net.URI;
 import java.util.Arrays;
 import java.util.Collection;
@@ -23,6 +24,7 @@ import java.util.Collections;
 
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.HttpMethod;
+import org.springframework.http.MediaType;
 
 /**
  * Standard implementation of {@link OperationRequest}.
@@ -33,6 +35,8 @@ public class StandardOperationRequest implements OperationRequest {
 
 	private byte[] content;
 
+	private String characterEncoding;
+
 	private HttpHeaders headers;
 
 	private HttpMethod method;
@@ -60,6 +64,7 @@ public class StandardOperationRequest implements OperationRequest {
 		this.uri = uri;
 		this.method = method;
 		this.content = content;
+		this.characterEncoding = detectCharsetFromContentTypeHeader(headers);
 		this.headers = headers;
 		this.parameters = parameters;
 		this.parts = parts;
@@ -69,6 +74,17 @@ public class StandardOperationRequest implements OperationRequest {
 	public byte[] getContent() {
 		return Arrays.copyOf(this.content, this.content.length);
 	}
+	
+	@Override
+	public String getContentAsString() throws UnsupportedEncodingException {
+		if (content.length > 0) {
+			return characterEncoding != null ?
+					new String(content, characterEncoding) : new String(content);
+		}
+		else {
+			return "";
+		}
+	}
 
 	@Override
 	public HttpHeaders getHeaders() {
@@ -95,4 +111,14 @@ public class StandardOperationRequest implements OperationRequest {
 		return this.uri;
 	}
 
+	private String detectCharsetFromContentTypeHeader(HttpHeaders headers) {
+		if (headers == null) {
+			return null;
+		}
+		MediaType contentType = headers.getContentType();
+		if (contentType == null) {
+			return null;
+		}
+		return contentType.getParameter("charset");
+	}
 }

spring-restdocs-core/src/main/java/org/springframework/restdocs/operation/StandardOperationResponse.java

@@ -16,8 +16,11 @@
 
 package org.springframework.restdocs.operation;
 
+import java.io.UnsupportedEncodingException;
+
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.HttpStatus;
+import org.springframework.http.MediaType;
 
 /**
  * Standard implementation of {@link OperationResponse}.
@@ -32,6 +35,8 @@ public class StandardOperationResponse implements OperationResponse {
 
 	private final byte[] content;
 
+	private String characterEncoding;
+
 	/**
 	 * Creates a new response with the given {@code status}, {@code headers}, and
 	 * {@code content}.
@@ -45,6 +50,7 @@ public class StandardOperationResponse implements OperationResponse {
 		this.status = status;
 		this.headers = headers;
 		this.content = content;
+		this.characterEncoding = detectCharsetFromContentTypeHeader(headers);
 	}
 
 	@Override
@@ -62,4 +68,25 @@ public class StandardOperationResponse implements OperationResponse {
 		return this.content;
 	}
 
+	@Override
+	public String getContentAsString() throws UnsupportedEncodingException {
+		if (content.length > 0) {
+			return characterEncoding != null ?
+					new String(content, characterEncoding) : new String(content);
+		}
+		else {
+			return "";
+		}
+	}
+
+	private String detectCharsetFromContentTypeHeader(HttpHeaders headers) {
+		if (headers == null) {
+			return null;
+		}
+		MediaType contentType = headers.getContentType();
+		if (contentType == null) {
+			return null;
+		}
+		return contentType.getParameter("charset");
+	}
 }

spring-restdocs-core/src/test/java/org/springframework/restdocs/http/HttpRequestSnippetTests.java

@@ -84,7 +84,23 @@ public class HttpRequestSnippetTests {
 				.request("http://localhost/foo").method("POST").content("Hello, world")
 				.build());
 	}
+	
+	@Test
+	public void postRequestWithCharset() throws IOException {
+		this.snippet.expectHttpRequest("post-request-with-charset").withContents(
+				httpRequest(POST, "/foo")
+				.header(HttpHeaders.HOST, "localhost")
+				.header("Content-Type", "text/plain;charset=UTF-8").content(
+						"こんにちわ, 世界")); // Hello, World in japanese.
 
+		new HttpRequestSnippet().document(new OperationBuilder(
+				"post-request-with-charset", this.snippet.getOutputDirectory())
+				.request("http://localhost/foo").method("POST")
+				.header("Content-Type", "text/plain;charset=UTF-8")
+				.content("こんにちわ, 世界")
+				.build());
+	}
+	
 	@Test
 	public void postRequestWithParameter() throws IOException {
 		this.snippet.expectHttpRequest("post-request-with-parameter").withContents(

spring-restdocs-core/src/test/java/org/springframework/restdocs/http/HttpResponseSnippetTests.java

@@ -84,7 +84,15 @@ public class HttpResponseSnippetTests {
 		new HttpResponseSnippet().document(new OperationBuilder("response-with-content",
 				this.snippet.getOutputDirectory()).response().content("content").build());
 	}
-
+	
+	@Test
+	public void responseWithCharset() throws IOException {
+		this.snippet.expectHttpResponse("response-with-charset").withContents(
+				httpResponse(OK).header("Content-Type", "text/plain;charset=UTF-8").content("コンテンツ"));
+		new HttpResponseSnippet().document(new OperationBuilder("response-with-charset",
+				this.snippet.getOutputDirectory()).response().header("Content-Type", "text/plain;charset=UTF-8").content("コンテンツ").build());
+	}
+	
 	@Test
 	public void responseWithCustomSnippetAttributes() throws IOException {
 		this.snippet.expectHttpResponse("response-with-snippet-attributes").withContents(