org.glassfish.jersey.server.internal.JsonWithPaddingInterceptor Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of jersey-server Show documentation
Show all versions of jersey-server Show documentation
Jersey core server implementation
/*
* Copyright (c) 2012, 2018 Oracle and/or its affiliates. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v. 2.0, which is available at
* http://www.eclipse.org/legal/epl-2.0.
*
* This Source Code may also be made available under the following Secondary
* Licenses when the conditions for such availability set forth in the
* Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
* version 2 with the GNU Classpath Exception, which is available at
* https://www.gnu.org/software/classpath/license.html.
*
* SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
*/
package org.glassfish.jersey.server.internal;
import java.io.IOException;
import java.lang.annotation.Annotation;
import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.stream.Collectors;
import javax.ws.rs.WebApplicationException;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.MultivaluedMap;
import javax.ws.rs.core.UriInfo;
import javax.ws.rs.ext.InterceptorContext;
import javax.ws.rs.ext.WriterInterceptor;
import javax.ws.rs.ext.WriterInterceptorContext;
import javax.annotation.Priority;
import javax.inject.Inject;
import javax.inject.Provider;
import org.glassfish.jersey.JerseyPriorities;
import org.glassfish.jersey.message.MessageUtils;
import org.glassfish.jersey.server.ContainerRequest;
import org.glassfish.jersey.server.JSONP;
/**
* A {@link WriterInterceptor} implementation for JSONP format. This interceptor wraps a JSON stream obtained by a underlying
* JSON provider into a callback function that can be defined by the {@link JSONP} annotation.
*
* @author Michal Gajdos
* @see JSONP
*/
@Priority(JerseyPriorities.POST_ENTITY_CODER)
// this interceptor has to run after content encoders (e.g. gzip/deflate), otherwise the added content (padding with the callback
// method call would not be encoded.
public class JsonWithPaddingInterceptor implements WriterInterceptor {
private static final Map> JAVASCRIPT_TYPES;
static {
JAVASCRIPT_TYPES = new HashMap<>(2);
JAVASCRIPT_TYPES.put("application", Arrays.asList("x-javascript", "ecmascript", "javascript")
.stream().collect(Collectors.toSet()));
JAVASCRIPT_TYPES.put("text", Arrays.asList("javascript", "x-javascript", "ecmascript", "jscript")
.stream().collect(Collectors.toSet()));
}
@Inject
private Provider containerRequestProvider;
@Override
public void aroundWriteTo(final WriterInterceptorContext context) throws IOException, WebApplicationException {
final boolean isJavascript = isJavascript(context.getMediaType());
final JSONP jsonp = getJsonpAnnotation(context);
final boolean wrapIntoCallback = isJavascript && jsonp != null;
if (wrapIntoCallback) {
context.setMediaType(MediaType.APPLICATION_JSON_TYPE);
context.getOutputStream().write(getCallbackName(jsonp).getBytes(MessageUtils.getCharset(context.getMediaType())));
context.getOutputStream().write('(');
}
context.proceed();
if (wrapIntoCallback) {
context.getOutputStream().write(')');
}
}
/**
* Returns a flag whether the given {@link MediaType media type} belongs to the group of JavaScript media types.
*
* @param mediaType media type to check.
* @return {@code true} if the given media type is a JavaScript type, {@code false} otherwise (or if the media type is
* {@code null}}
*/
private boolean isJavascript(final MediaType mediaType) {
if (mediaType == null) {
return false;
}
final Set subtypes = JAVASCRIPT_TYPES.get(mediaType.getType());
return subtypes != null && subtypes.contains(mediaType.getSubtype());
}
/**
* Returns a JavaScript callback name to wrap the JSON entity into. The callback name is determined from the {@link JSONP}
* annotation.
*
* @param jsonp {@link JSONP} annotation to determine the callback name from.
* @return a JavaScript callback name.
*/
private String getCallbackName(final JSONP jsonp) {
String callback = jsonp.callback();
if (!"".equals(jsonp.queryParam())) {
final ContainerRequest containerRequest = containerRequestProvider.get();
final UriInfo uriInfo = containerRequest.getUriInfo();
final MultivaluedMap queryParameters = uriInfo.getQueryParameters();
final List queryParameter = queryParameters.get(jsonp.queryParam());
callback = (queryParameter != null && !queryParameter.isEmpty()) ? queryParameter.get(0) : callback;
}
return callback;
}
/**
* Returns a {@link JSONP} annotation of the resource method responsible for handling the current request.
*
* @param context an {@link InterceptorContext interceptor context} to obtain the annotation from.
* @return {@link JSONP} annotation or {@code null} if the resource method is not annotated with this annotation.
* @see javax.ws.rs.ext.InterceptorContext#getAnnotations()
*/
private JSONP getJsonpAnnotation(final InterceptorContext context) {
final Annotation[] annotations = context.getAnnotations();
if (annotations != null && annotations.length > 0) {
for (final Annotation annotation : annotations) {
if (annotation instanceof JSONP) {
return (JSONP) annotation;
}
}
}
return null;
}
}