/*
* Copyright 2002-2014 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.web.servlet.support;
import javax.servlet.http.HttpServletRequest;
import org.springframework.util.Assert;
import org.springframework.util.StringUtils;
import org.springframework.web.context.request.RequestAttributes;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;
import org.springframework.web.util.UriComponentsBuilder;
import org.springframework.web.util.UrlPathHelper;
import org.springframework.web.util.WebUtils;
/**
* A UriComponentsBuilder that extracts information from an HttpServletRequest.
*
* @author Rossen Stoyanchev
* @since 3.1
*/
public class ServletUriComponentsBuilder extends UriComponentsBuilder {
private String servletRequestURI;
/**
* Default constructor. Protected to prevent direct instantiation.
*
* @see #fromContextPath(HttpServletRequest)
* @see #fromServletMapping(HttpServletRequest)
* @see #fromRequest(HttpServletRequest)
* @see #fromCurrentContextPath()
* @see #fromCurrentServletMapping()
* @see #fromCurrentRequest()
*/
protected ServletUriComponentsBuilder() {
}
/**
* Prepare a builder from the host, port, scheme, and context path of
* an HttpServletRequest.
*/
public static ServletUriComponentsBuilder fromContextPath(HttpServletRequest request) {
ServletUriComponentsBuilder builder = fromRequest(request);
builder.replacePath(request.getContextPath());
builder.replaceQuery(null);
return builder;
}
/**
* Prepare a builder from the host, port, scheme, context path, and
* servlet mapping of an HttpServletRequest. The results may vary depending
* on the type of servlet mapping used.
*
* <p>If the servlet is mapped by name, e.g. {@code "/main/*"}, the path
* will end with "/main". If the servlet is mapped otherwise, e.g.
* {@code "/"} or {@code "*.do"}, the result will be the same as
* if calling {@link #fromContextPath(HttpServletRequest)}.
*/
public static ServletUriComponentsBuilder fromServletMapping(HttpServletRequest request) {
ServletUriComponentsBuilder builder = fromContextPath(request);
if (StringUtils.hasText(new UrlPathHelper().getPathWithinServletMapping(request))) {
builder.path(request.getServletPath());
}
return builder;
}
/**
* Prepare a builder from the host, port, scheme, and path of
* an HttpServletRequest.
*/
public static ServletUriComponentsBuilder fromRequestUri(HttpServletRequest request) {
ServletUriComponentsBuilder builder = fromRequest(request);
builder.pathFromRequest(request);
builder.replaceQuery(null);
return builder;
}
/**
* Prepare a builder by copying the scheme, host, port, path, and
* query string of an HttpServletRequest.
*/
public static ServletUriComponentsBuilder fromRequest(HttpServletRequest request) {
String scheme = request.getScheme();
String host = request.getServerName();
int port = request.getServerPort();
String hostHeader = request.getHeader("X-Forwarded-Host");
if (StringUtils.hasText(hostHeader)) {
String[] hosts = StringUtils.commaDelimitedListToStringArray(hostHeader);
String hostToUse = hosts[0];
if (hostToUse.contains(":")) {
String[] hostAndPort = StringUtils.split(hostToUse, ":");
host = hostAndPort[0];
port = Integer.parseInt(hostAndPort[1]);
}
else {
host = hostToUse;
port = -1;
}
}
String portHeader = request.getHeader("X-Forwarded-Port");
if (StringUtils.hasText(portHeader)) {
port = Integer.parseInt(portHeader);
}
String protocolHeader = request.getHeader("X-Forwarded-Proto");
if (StringUtils.hasText(protocolHeader)) {
scheme = protocolHeader;
}
ServletUriComponentsBuilder builder = new ServletUriComponentsBuilder();
builder.scheme(scheme);
builder.host(host);
if (scheme.equals("http") && port != 80 || scheme.equals("https") && port != 443) {
builder.port(port);
}
builder.pathFromRequest(request);
builder.query(request.getQueryString());
return builder;
}
/**
* Same as {@link #fromContextPath(HttpServletRequest)} except the
* request is obtained through {@link RequestContextHolder}.
*/
public static ServletUriComponentsBuilder fromCurrentContextPath() {
return fromContextPath(getCurrentRequest());
}
/**
* Same as {@link #fromServletMapping(HttpServletRequest)} except the
* request is obtained through {@link RequestContextHolder}.
*/
public static ServletUriComponentsBuilder fromCurrentServletMapping() {
return fromServletMapping(getCurrentRequest());
}
/**
* Same as {@link #fromRequestUri(HttpServletRequest)} except the
* request is obtained through {@link RequestContextHolder}.
*/
public static ServletUriComponentsBuilder fromCurrentRequestUri() {
return fromRequestUri(getCurrentRequest());
}
/**
* Same as {@link #fromRequest(HttpServletRequest)} except the
* request is obtained through {@link RequestContextHolder}.
*/
public static ServletUriComponentsBuilder fromCurrentRequest() {
return fromRequest(getCurrentRequest());
}
/**
* Obtain the request through {@link RequestContextHolder}.
*/
protected static HttpServletRequest getCurrentRequest() {
RequestAttributes requestAttributes = RequestContextHolder.getRequestAttributes();
Assert.state(requestAttributes != null, "Could not find current request via RequestContextHolder");
Assert.isInstanceOf(ServletRequestAttributes.class, requestAttributes);
HttpServletRequest servletRequest = ((ServletRequestAttributes) requestAttributes).getRequest();
Assert.state(servletRequest != null, "Could not find current HttpServletRequest");
return servletRequest;
}
private void pathFromRequest(HttpServletRequest request) {
this.servletRequestURI = request.getRequestURI();
replacePath(request.getRequestURI());
}
/**
* Removes any path extension from the {@link HttpServletRequest#getRequestURI()
* requestURI}. This method must be invoked before any calls to {@link #path(String)}
* or {@link #pathSegment(String...)}.
* <pre>
* // GET http://foo.com/rest/books/6.json
*
* ServletUriComponentsBuilder builder = ServletUriComponentsBuilder.fromRequestUri(this.request);
* String ext = builder.removePathExtension();
* String uri = builder.path("/pages/1.{ext}").buildAndExpand(ext).toUriString();
*
* assertEquals("http://foo.com/rest/books/6/pages/1.json", result);
* </pre>
* @return the removed path extension for possible re-use, or {@code null}
* @since 4.0
*/
public String removePathExtension() {
String extension = null;
if (this.servletRequestURI != null) {
String filename = WebUtils.extractFullFilenameFromUrlPath(this.servletRequestURI);
extension = StringUtils.getFilenameExtension(filename);
if (!StringUtils.isEmpty(extension)) {
int end = this.servletRequestURI.length() - (extension.length() + 1);
replacePath(this.servletRequestURI.substring(0, end));
}
this.servletRequestURI = null;
}
return extension;
}
}