Accept all media types in StringDecodere

This commit adds the "*/*" media type in the list of compatible media
types for the StringDecoder. This allows this decoder to decoder
payloads of any media type as long as the target type is String.

Fixes #87

spring-web-reactive/src/main/java/org/springframework/core/codec/support/StringDecoder.java

@@ -25,6 +25,7 @@ import reactor.core.publisher.Flux;
 import org.springframework.core.ResolvableType;
 import org.springframework.core.io.buffer.DataBuffer;
 import org.springframework.util.MimeType;
+import org.springframework.util.MimeTypeUtils;
 
 /**
  * Decode from a bytes stream to a String stream.
@@ -63,7 +64,7 @@ public class StringDecoder extends AbstractDecoder<String> {
 	 * and decode a single consolidated String or re-emit items as they are provided
 	 */
 	public StringDecoder(boolean reduceToSingleBuffer) {
-		super(new MimeType("text", "*", DEFAULT_CHARSET));
+		super(new MimeType("text", "*", DEFAULT_CHARSET), MimeTypeUtils.ALL);
 		this.reduceToSingleBuffer = reduceToSingleBuffer;
 	}
 

spring-web-reactive/src/test/java/org/springframework/core/codec/support/StringDecoderTests.java

@@ -48,8 +48,9 @@ public class StringDecoderTests extends AbstractAllocatingTestCase {
 	public void canDecode() {
 		assertTrue(decoder.canDecode(ResolvableType.forClass(String.class), MediaType.TEXT_PLAIN));
 		assertTrue(decoder.canDecode(ResolvableType.forClass(String.class), MediaType.TEXT_HTML));
+		assertTrue(decoder.canDecode(ResolvableType.forClass(String.class), MediaType.APPLICATION_JSON));
 		assertFalse(decoder.canDecode(ResolvableType.forClass(Integer.class), MediaType.TEXT_PLAIN));
-		assertFalse(decoder.canDecode(ResolvableType.forClass(String.class), MediaType.APPLICATION_JSON));
+		assertFalse(decoder.canDecode(ResolvableType.forClass(Pojo.class), MediaType.APPLICATION_JSON));
 	}
 
 	@Test

spring-web-reactive/src/test/java/org/springframework/web/client/reactive/WebClientIntegrationTests.java

@@ -130,6 +130,28 @@ public class WebClientIntegrationTests {
 		assertEquals("text/plain", request.getHeader(HttpHeaders.ACCEPT));
 	}
 
+	@Test
+	public void shouldGetJsonAsMonoOfString() throws Exception {
+
+		HttpUrl baseUrl = server.url("/json");
+		String content = "{\"bar\":\"barbar\",\"foo\":\"foofoo\"}";
+		this.server.enqueue(new MockResponse().setHeader("Content-Type", "application/json")
+				.setBody(content));
+
+		Mono<String> result = this.webClient
+				.perform(get(baseUrl.toString())
+						.accept(MediaType.APPLICATION_JSON))
+				.extract(body(String.class));
+
+		TestSubscriber<String> ts = new TestSubscriber();
+		result.subscribe(ts);
+		ts.awaitAndAssertNextValues(content).assertComplete();
+		RecordedRequest request = server.takeRequest();
+		assertEquals(1, server.getRequestCount());
+		assertEquals("/json", request.getPath());
+		assertEquals("application/json", request.getHeader(HttpHeaders.ACCEPT));
+	}
+
 	@Test
 	public void shouldGetJsonAsMonoOfPojo() throws Exception {