support multipart/form-data requests (#168)

Author: tangiel

endpoints-framework/build.gradle

@@ -96,6 +96,7 @@ dependencies {
     exclude group: 'com.google.guava', module: 'guava-jdk5'
   }
   compile group: 'com.google.code.findbugs', name: 'jsr305', version: findbugsVersion
+  compile group: 'commons-fileupload', name: 'commons-fileupload', version: fileUploadVersion
   compile group: 'io.swagger', name: 'swagger-models', version: swaggerVersion
   compile group: 'io.swagger', name: 'swagger-core', version: swaggerVersion
   compile group: 'org.slf4j', name: 'slf4j-nop', version: slf4jVersion

endpoints-framework/src/main/java/com/google/api/server/spi/request/RestServletRequestParamReader.java

@@ -31,9 +31,13 @@
 import com.fasterxml.jackson.databind.node.ArrayNode;
 import com.fasterxml.jackson.databind.node.ObjectNode;
 
+import org.apache.commons.fileupload.FileItemIterator;
+import org.apache.commons.fileupload.FileItemStream;
+import org.apache.commons.fileupload.FileUploadException;
+import org.apache.commons.fileupload.servlet.ServletFileUpload;
+
 import java.io.IOException;
 import java.lang.reflect.InvocationTargetException;
-import java.util.Collection;
 import java.util.Enumeration;
 import java.util.List;
 import java.util.Map;
@@ -83,13 +87,35 @@ public Object[] read() throws ServiceException {
         return new Object[0];
       }
       HttpServletRequest servletRequest = endpointsContext.getRequest();
-      String requestBody = IoUtil.readRequestBody(servletRequest);
-      logger.log(Level.FINE, "requestBody=" + requestBody);
-      // Unlike the Lily protocol, which essentially always requires a JSON body to exist (due to
-      // path and query parameters being injected into the body), bodies are optional here, so we
-      // create an empty body and inject named parameters to make deserialize work.
-      JsonNode node = Strings.isEmptyOrWhitespace(requestBody) ? objectReader.createObjectNode()
-          : objectReader.readTree(requestBody);
+      JsonNode node;
+      // multipart/form-data requests can be used for requests which have no resource body. In
+      // this case, each part represents a named parameter instead.
+      if (ServletFileUpload.isMultipartContent(servletRequest)) {
+        try {
+          ServletFileUpload upload = new ServletFileUpload();
+          FileItemIterator iter = upload.getItemIterator(servletRequest);
+          ObjectNode obj = (ObjectNode) objectReader.createObjectNode();
+          while (iter.hasNext()) {
+            FileItemStream item = iter.next();
+            if (item.isFormField()) {
+              obj.put(item.getFieldName(), IoUtil.readStream(item.openStream()));
+            } else {
+              throw new BadRequestException("unable to parse multipart form field");
+            }
+          }
+          node = obj;
+        } catch (FileUploadException e) {
+          throw new BadRequestException("unable to parse multipart request", e);
+        }
+      } else {
+        String requestBody = IoUtil.readRequestBody(servletRequest);
+        logger.log(Level.FINE, "requestBody=" + requestBody);
+        // Unlike the Lily protocol, which essentially always requires a JSON body to exist (due to
+        // path and query parameters being injected into the body), bodies are optional here, so we
+        // create an empty body and inject named parameters to make deserialize work.
+        node = Strings.isEmptyOrWhitespace(requestBody) ? objectReader.createObjectNode()
+            : objectReader.readTree(requestBody);
+      }
       if (!node.isObject()) {
         throw new BadRequestException("expected a JSON object body");
       }

endpoints-framework/src/test/java/com/google/api/server/spi/request/RestServletRequestParamReaderTest.java

@@ -204,6 +204,31 @@ public void arrayPathParam() throws Exception {
         .containsExactly(ImmutableList.of("4", "3", "2", "1"));
   }
 
+  @Test
+  public void multipartFormData() throws Exception {
+    endpointMethod = EndpointMethod.create(TestApi.class,
+        TestApi.class.getMethod("testFormData", String.class, Integer.class));
+    methodConfig = apiConfig.getApiClassConfig().getMethods().get(endpointMethod);
+    request.setContentType("multipart/form-data; boundary=----test");
+    request.setMethod("POST");
+    String requestContent =
+        "------test\r\n" +
+        "Content-Disposition: form-data; name=\"foo\"\r\n\r\n" +
+        "test\r\n" +
+        "------test\r\n" +
+        "Content-Disposition: form-data; name=\"bar\"\r\n\r\n" +
+        "1234\r\n" +
+        "------test--\r\n";
+    request.setContent(requestContent.getBytes(StandardCharsets.UTF_8));
+    RestServletRequestParamReader reader = createReader(ImmutableMap.<String, String>of());
+
+    Object[] params = reader.read();
+
+    assertThat(params).hasLength(endpointMethod.getParameterClasses().length);
+    assertThat(params).asList()
+        .containsExactly("test", 1234);
+  }
+
   private RestServletRequestParamReader createReader(Map<String, String> rawPathParameters) {
     EndpointsContext endpointsContext =
         new EndpointsContext("GET", "/", request, new MockHttpServletResponse(), true);
@@ -243,6 +268,15 @@ public void test(
         path = "testArrayPathParam/{values}")
     public void testArrayPathParam(@Named("values") ArrayList<String> values) {
     }
+
+    @ApiMethod(
+        name = "testFormData",
+        httpMethod = HttpMethod.POST,
+        path = "testFormData")
+    public void testFormData(
+        @Nullable @Named("foo") String foo,
+        @Nullable @Named("bar") Integer bar) {
+    }
   }
 
   private static byte[] compress(byte[] bytes) {

gradle.properties

@@ -11,6 +11,7 @@ jacksonVersion=2.9.6
 gradleAppenginePluginVersion=1.9.59
 appengineVersion=1.9.60
 apiclientVersion=1.23.0
+fileUploadVersion=1.3.3
 findbugsVersion=3.0.1
 swaggerVersion=1.5.9
 slf4jVersion=1.7.21