Allow streaming of multipart requests in Zuul proxy

docs/src/main/asciidoc/spring-cloud-netflix.adoc

@@ -860,6 +860,37 @@ An application with the `@EnableZuulProxy` could act as a standalone
 server if you set a default route ("/"), for example `zuul.route.home:
 /` would route all traffic (i.e. "/**") to the "home" service.
 
+=== Uploading Files through Zuul
+
+If you `@EnableZuulProxy` you can use the proxy paths to
+upload files and it should just work as long as the files
+are small. For large files there is an alternative path 
+which bypasses the Spring `DispatcherServlet` (to 
+avoid multipart processing) in "/zuul/*". I.e. if
+`zuul.routes.customers=/customers/**` then you can 
+POST large files to "/zuul/customers/*". The servlet
+path is externalized via `zuul.servletPath`. Extremely
+large files will also require elevated timeout settings
+if the proxy route takes you through a Ribbon load
+balancer, e.g.
+
+.application.yml
+[source,yaml]
+----
+hystrix.command.default.execution.isolation.thread.timeoutInMilliseconds: 60000
+ribbon:
+  ConnectTimeout: 3000
+  ReadTimeout: 60000
+----
+
+Note that for streaming to work with large files, you need to use chunked encoding in the request (which some browsers
+do not do by default). E.g. on the command line:
+
+----
+$ curl -v -H "Transfer-Encoding: chunked" \
+    -F "file=@mylarge.iso" localhost:9999/zuul/simple/file
+----
+
 === Plain Embedded Zuul
 
 You can also run a Zuul server without the proxying, or switch on parts of the proxying platform selectively, if you

spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/zuul/ZuulConfiguration.java

@@ -20,6 +20,7 @@ import java.util.Map;
 
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
+import org.springframework.boot.context.embedded.ServletRegistrationBean;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
 import org.springframework.cloud.context.scope.refresh.RefreshScopeRefreshedEvent;
 import org.springframework.cloud.netflix.zuul.filters.RouteLocator;
@@ -73,6 +74,12 @@ public class ZuulConfiguration {
 		return new ZuulRefreshListener();
 	}
 
+	@Bean
+	public ServletRegistrationBean zuulServlet() {
+		return new ServletRegistrationBean(new ZuulServlet(),
+				this.zuulProperties.getServletPattern());
+	}
+
 	// pre filters
 
 	@Bean

spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/zuul/filters/ZuulProperties.java

@@ -51,6 +51,8 @@ public class ZuulProperties {
 
 	private List<String> ignoredServices = new ArrayList<String>();
 
+	private String servletPath = "/zuul";
+
 	@PostConstruct
 	public void init() {
 		for (Entry<String, ZuulRoute> entry : this.routes.entrySet()) {
@@ -132,4 +134,15 @@ public class ZuulProperties {
 
 	}
 
+	public String getServletPattern() {
+		String path = this.servletPath;
+		if (!path.startsWith("/")) {
+			path = "/" + path;
+		}
+		if (!path.contains("*")) {
+			path = path.endsWith("/") ? (path + "*") : (path + "/*");
+		}
+		return path;
+	}
+
 }

spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/zuul/filters/pre/FormBodyWrapperFilter.java

@@ -37,6 +37,7 @@ import org.springframework.util.MultiValueMap;
 import org.springframework.util.ReflectionUtils;
 import org.springframework.web.multipart.MultipartFile;
 import org.springframework.web.multipart.MultipartRequest;
+import org.springframework.web.servlet.DispatcherServlet;
 
 import com.netflix.zuul.ZuulFilter;
 import com.netflix.zuul.context.RequestContext;
@@ -76,17 +77,23 @@ public class FormBodyWrapperFilter extends ZuulFilter {
 		if (contentType == null) {
 			return false;
 		}
-		// Only use this filter for form data
+		// Only use this filter for form data and only for multipart data in a
+		// DispatcherServlet handler
 		try {
 			MediaType mediaType = MediaType.valueOf(contentType);
 			return MediaType.APPLICATION_FORM_URLENCODED.includes(mediaType)
-					|| MediaType.MULTIPART_FORM_DATA.includes(mediaType);
+					|| (isDispatcherServletRequest(request) && MediaType.MULTIPART_FORM_DATA
+							.includes(mediaType));
 		}
 		catch (InvalidMediaTypeException ex) {
 			return false;
 		}
 	}
 
+	private boolean isDispatcherServletRequest(HttpServletRequest request) {
+		return request.getAttribute(DispatcherServlet.WEB_APPLICATION_CONTEXT_ATTRIBUTE) != null;
+	}
+
 	@Override
 	public Object run() {
 		RequestContext ctx = RequestContext.getCurrentContext();

spring-cloud-netflix-core/src/test/java/org/springframework/cloud/netflix/zuul/FormZuulProxyApplicationTests.java

@@ -34,6 +34,7 @@ import org.springframework.boot.test.IntegrationTest;
 import org.springframework.boot.test.SpringApplicationConfiguration;
 import org.springframework.boot.test.TestRestTemplate;
 import org.springframework.cloud.netflix.ribbon.RibbonClient;
+import org.springframework.cloud.netflix.ribbon.RibbonClients;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.http.HttpEntity;
@@ -137,7 +138,9 @@ public class FormZuulProxyApplicationTests {
 @EnableAutoConfiguration
 @RestController
 @EnableZuulProxy
-@RibbonClient(name = "simple", configuration = FormRibbonClientConfiguration.class)
+@RibbonClients({
+		@RibbonClient(name = "simple", configuration = FormRibbonClientConfiguration.class),
+		@RibbonClient(name = "psimple", configuration = FormRibbonClientConfiguration.class) })
 @Slf4j
 class FormZuulProxyApplication {
 
@@ -211,8 +214,10 @@ class FormZuulProxyApplication {
 
 	public static void main(String[] args) {
 		new SpringApplicationBuilder(FormZuulProxyApplication.class).properties(
-				"zuul.routes.simple:/simple/**", "multipart.maxFileSize:4096MB",
-				"multipart.maxRequestSize:4096MB").run(args);
+				"zuul.routes.simple:/simple/**",
+				"zuul.routes.direct.url:http://localhost:9999",
+				"multipart.maxFileSize:4096MB", "multipart.maxRequestSize:4096MB").run(
+				args);
 	}
 
 }

spring-cloud-netflix-core/src/test/java/org/springframework/cloud/netflix/zuul/FormZuulServletProxyApplicationTests.java

+/*
+ * Copyright 2013-2015 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.cloud.netflix.zuul;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.Arrays;
+import java.util.Map;
+
+import lombok.extern.slf4j.Slf4j;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.boot.actuate.trace.InMemoryTraceRepository;
+import org.springframework.boot.actuate.trace.TraceRepository;
+import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
+import org.springframework.boot.builder.SpringApplicationBuilder;
+import org.springframework.boot.test.IntegrationTest;
+import org.springframework.boot.test.SpringApplicationConfiguration;
+import org.springframework.boot.test.TestRestTemplate;
+import org.springframework.cloud.netflix.ribbon.RibbonClient;
+import org.springframework.cloud.netflix.ribbon.RibbonClients;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.http.HttpEntity;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpMethod;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.MediaType;
+import org.springframework.http.ResponseEntity;
+import org.springframework.test.annotation.DirtiesContext;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+import org.springframework.test.context.web.WebAppConfiguration;
+import org.springframework.util.LinkedMultiValueMap;
+import org.springframework.util.MultiValueMap;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestMethod;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.RestController;
+import org.springframework.web.multipart.MultipartFile;
+
+import com.netflix.appinfo.EurekaInstanceConfig;
+import com.netflix.loadbalancer.BaseLoadBalancer;
+import com.netflix.loadbalancer.ILoadBalancer;
+import com.netflix.loadbalancer.Server;
+import com.netflix.zuul.ZuulFilter;
+
+import static org.junit.Assert.assertEquals;
+
+@RunWith(SpringJUnit4ClassRunner.class)
+@SpringApplicationConfiguration(classes = FormZuulServletProxyApplication.class)
+@WebAppConfiguration
+@IntegrationTest({ "server.port:0", "zuul.routes.simple:/zuul/simple/**" })
+@DirtiesContext
+public class FormZuulServletProxyApplicationTests {
+
+	@Value("${local.server.port}")
+	private int port;
+
+	@Test
+	public void postWithForm() {
+		MultiValueMap<String, String> form = new LinkedMultiValueMap<String, String>();
+		form.set("foo", "bar");
+		HttpHeaders headers = new HttpHeaders();
+		headers.setContentType(MediaType.APPLICATION_FORM_URLENCODED);
+		ResponseEntity<String> result = new TestRestTemplate().exchange(
+				"http://localhost:" + this.port + "/zuul/simple/form", HttpMethod.POST,
+				new HttpEntity<MultiValueMap<String, String>>(form, headers),
+				String.class);
+		assertEquals(HttpStatus.OK, result.getStatusCode());
+		assertEquals("Posted! {foo=[bar]}", result.getBody());
+	}
+
+	@Test
+	public void postWithMultipartForm() {
+		MultiValueMap<String, String> form = new LinkedMultiValueMap<String, String>();
+		form.set("foo", "bar");
+		HttpHeaders headers = new HttpHeaders();
+		headers.setContentType(MediaType.MULTIPART_FORM_DATA);
+		ResponseEntity<String> result = new TestRestTemplate().exchange(
+				"http://localhost:" + this.port + "/zuul/simple/form", HttpMethod.POST,
+				new HttpEntity<MultiValueMap<String, String>>(form, headers),
+				String.class);
+		assertEquals(HttpStatus.OK, result.getStatusCode());
+		assertEquals("Posted! {foo=[bar]}", result.getBody());
+	}
+
+	@Test
+	public void postWithMultipartFile() {
+		MultiValueMap<String, Object> form = new LinkedMultiValueMap<String, Object>();
+		HttpHeaders part = new HttpHeaders();
+		part.setContentType(MediaType.TEXT_PLAIN);
+		part.setContentDispositionFormData("file", "foo.txt");
+		form.set("foo", new HttpEntity<byte[]>("bar".getBytes(), part));
+		HttpHeaders headers = new HttpHeaders();
+		headers.setContentType(MediaType.MULTIPART_FORM_DATA);
+		ResponseEntity<String> result = new TestRestTemplate().exchange(
+				"http://localhost:" + this.port + "/zuul/simple/file", HttpMethod.POST,
+				new HttpEntity<MultiValueMap<String, Object>>(form, headers),
+				String.class);
+		assertEquals(HttpStatus.OK, result.getStatusCode());
+		assertEquals("Posted! bar", result.getBody());
+	}
+
+	@Test
+	public void postWithUTF8Form() {
+		MultiValueMap<String, String> form = new LinkedMultiValueMap<String, String>();
+		form.set("foo", "bar");
+		HttpHeaders headers = new HttpHeaders();
+		headers.setContentType(MediaType
+				.valueOf(MediaType.APPLICATION_FORM_URLENCODED_VALUE + "; charset=UTF-8"));
+		ResponseEntity<String> result = new TestRestTemplate().exchange(
+				"http://localhost:" + this.port + "/zuul/simple/form", HttpMethod.POST,
+				new HttpEntity<MultiValueMap<String, String>>(form, headers),
+				String.class);
+		assertEquals(HttpStatus.OK, result.getStatusCode());
+		assertEquals("Posted! {foo=[bar]}", result.getBody());
+	}
+}
+
+// Don't use @SpringBootApplication because we don't want to component scan
+@Configuration
+@EnableAutoConfiguration
+@RestController
+@EnableZuulProxy
+@RibbonClients(@RibbonClient(name = "simple", configuration = ServletFormRibbonClientConfiguration.class))
+@Slf4j
+class FormZuulServletProxyApplication {
+
+	@RequestMapping(value = "/form", method = RequestMethod.POST)
+	public String accept(@RequestParam MultiValueMap<String, String> form)
+			throws IOException {
+		return "Posted! " + form;
+	}
+
+	// TODO: Why does this not work if you add @RequestParam as above?
+	@RequestMapping(value = "/file", method = RequestMethod.POST)
+	public String file(@RequestParam(required = false) MultipartFile file)
+			throws IOException {
+		byte[] bytes = new byte[0];
+		if (file != null) {
+			if (file.getSize() > 1024) {
+				bytes = new byte[1024];
+				InputStream inputStream = file.getInputStream();
+				inputStream.read(bytes);
+				byte[] buffer = new byte[1024 * 1024 * 10];
+				while (inputStream.read(buffer) >= 0) {
+					log.info("Read more bytes");
+				}
+			}
+			else {
+				bytes = file.getBytes();
+			}
+		}
+		return "Posted! " + new String(bytes);
+	}
+
+	@Bean
+	public ZuulFilter sampleFilter() {
+		return new ZuulFilter() {
+
+			@Override
+			public String filterType() {
+				return "pre";
+			}
+
+			@Override
+			public boolean shouldFilter() {
+				return true;
+			}
+
+			@Override
+			public Object run() {
+				return null;
+			}
+
+			@Override
+			public int filterOrder() {
+				return 0;
+			}
+
+		};
+	}
+
+	@Bean
+	public TraceRepository traceRepository() {
+		return new InMemoryTraceRepository() {
+			@Override
+			public void add(Map<String, Object> map) {
+				if (map.containsKey("body")) {
+					map.get("body");
+				}
+				super.add(map);
+			}
+		};
+	}
+
+	public static void main(String[] args) {
+		new SpringApplicationBuilder(FormZuulProxyApplication.class).properties(
+				"zuul.routes.simple:/zuul/simple/**",
+				"zuul.routes.direct.url:http://localhost:9999",
+				"zuul.routes.direct.path:/zuul/direct/**",
+				"multipart.maxFileSize:4096MB", "multipart.maxRequestSize:4096MB").run(
+				args);
+	}
+
+}
+
+// Load balancer with fixed server list for "simple" pointing to localhost
+@Configuration
+class ServletFormRibbonClientConfiguration {
+
+	@Bean
+	public ILoadBalancer ribbonLoadBalancer(EurekaInstanceConfig instance) {
+		BaseLoadBalancer balancer = new BaseLoadBalancer();
+		balancer.setServersList(Arrays.asList(new Server("localhost", instance
+				.getNonSecurePort())));
+		// balancer.setServersList(Arrays.asList(new Server("localhost", 8000)));
+		return balancer;
+	}
+
+}

spring-cloud-netflix-core/src/test/resources/application.yml

@@ -14,6 +14,10 @@ eureka:
     fetchRegistry: false
 #error:
 #  path: /myerror
+hystrix.command.default.execution.isolation.thread.timeoutInMilliseconds: 60000
+ribbon:
+  ConnectTimeout: 3000
+  ReadTimeout: 60000
 management:
   context-path: /admin
 endpoints:

spring-cloud-netflix-core/src/test/resources/static/index.html

@@ -4,7 +4,19 @@
 		action="/simple/file">
 		File to upload: <input type="file" name="file"><br /> Name: <input
 			type="text" name="name"><br /> <br /> <input type="submit"
-			value="Upload"> Press here to upload the file via proxy!
+			value="Upload"> Press here to upload the file via ribbon proxy!
+	</form>
+	<form method="POST" enctype="multipart/form-data"
+		action="/direct/file">
+		File to upload: <input type="file" name="file"><br /> Name: <input
+			type="text" name="name"><br /> <br /> <input type="submit"
+			value="Upload"> Press here to upload the file via direct proxy!
+	</form>
+	<form method="POST" enctype="multipart/form-data"
+		action="/proxy/direct/file">
+		File to upload: <input type="file" name="file"><br /> Name: <input
+			type="text" name="name"><br /> <br /> <input type="submit"
+			value="Upload"> Press here to upload the file via proxy servlet!
 	</form>
 	<form method="POST" enctype="multipart/form-data"
 		action="/file">