First time post here. Using : Tomcat 8.0.26 JDK1.8.0 update 51 Apache MyFaces 2.2.8. Maven build of webapp war file Chrome 45.0.2454.101 m 64 bit Windows 7 64 bit
Trying to rewrite the entire request body in a filter using a http request wrapper. Not entirely sure if this is the right approach or even possible but researching similar examples it seems this approach should work. Created a simple test case with a one page test app, expecting the index.xhtml page's text value of "Welcome" to be replaced with the text "NEW TEXT HERE" found in the filter code, but I only get "Welcome" back when the page is rendered in the browser. Below is what I have in the index page, the filter and the web.xml and the pom.xml. The reason I can see is that the getInputStream() or getReader() calls are never called by the FacesServlet in the extended HttpServletRequestWrapper. I did override the getParameter function to put some simple debug output in there to ensure the wrapped request was actually used, so I know it's definitely getting into this class but not calling the methods that would return it the new body content. I even tried to re-read the entire request in the getParametersMap() from examples I found on the web, but this didn't seen to do the job either. It seems that the request body is somehow cached somewhere / somehow and not changable? Thanks in advance for any insight on this. index page code (index.xhtml) : --------------------------------------------------------------------------------- <!DOCTYPE html> <html lang="en" xmlns="http://www.w3.org/1999/xhtml"; xmlns:jsf="http://xmlns.jcp.org/jsf"; xmlns:h="http://xmlns.jcp.org/jsf/html";> <head jsf:id="head"> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/> <title>Test Webapp</title> </head> <body jsf:id="body"> <div><h1>Welcome</h1></div> </body> </html> Filter code : -------------------------------------------------------------------------- package com.testwebapp.reqrewrite.filter; import java.io.BufferedReader; import java.io.ByteArrayInputStream; import java.io.IOException; import java.io.InputStreamReader; import javax.servlet.Filter; import javax.servlet.FilterChain; import javax.servlet.FilterConfig; import javax.servlet.ReadListener; import javax.servlet.ServletException; import javax.servlet.ServletInputStream; import javax.servlet.ServletRequest; import javax.servlet.ServletResponse; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletRequestWrapper; public class RewriteBodyTestFilter implements Filter { public void init(FilterConfig filterConfig) throws ServletException { return; } public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException { String newReqBody = new String("<div><h1>NEW TEXT HERE</h1></div>"); HttpServletRequest req = (HttpServletRequest)request; RewriteBodyRequestWrapper rewriteBodyRequestWrapper = new RewriteBodyRequestWrapper(req, newReqBody); chain.doFilter(rewriteBodyRequestWrapper, response); } public void destroy() { return; } class RewriteBodyRequestWrapper extends HttpServletRequestWrapper { private byte[] buffer; public RewriteBodyRequestWrapper(HttpServletRequest req, String reqBody) throws IOException { super(req); System.out.println("entering RewriteBodyRequestWrapper() constructor"); this.buffer = reqBody.getBytes(); } @Override public ServletInputStream getInputStream() { System.out.println("entering RewriteBodyRequestWrapper().getInputStream()"); try { ByteArrayInputStream bais = new ByteArrayInputStream(buffer); BufferedServletInputStream bsis = new BufferedServletInputStream(bais); return bsis; } catch (Exception ex) { ex.printStackTrace(); throw new RuntimeException(ex); } } @Override public BufferedReader getReader() { System.out.println("entering RewriteBodyRequestWrapper().getReader()"); InputStreamReader isr = new InputStreamReader(getInputStream()); return new BufferedReader(isr); } } class BufferedServletInputStream extends ServletInputStream { ByteArrayInputStream bais; public BufferedServletInputStream(ByteArrayInputStream bais) { this.bais = bais; } @Override public int available() { return bais.available(); } @Override public boolean isFinished() { return bais.available() == 0; } @Override public boolean isReady() { return true; } @Override public void setReadListener(ReadListener readListener) { return; } @Override public int read() { return bais.read(); } @Override public int read(byte[] buf) { return this.read(buf, 0, buf.length); } @Override public int read(byte[] buf, int off, int len) { return bais.read(buf, off, len); } } } web.xml code: -------------------------------------------------------------------------------------------------- <?xml version="1.0" encoding="ISO-8859-1"?> <web-app xmlns="http://java.sun.com/xml/ns/j2ee"; xmlns:xsi=" http://www.w3.org/2001/XMLSchema-instance"; xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"; metadata-complete="true" version="3.0"> <display-name>Test Webapp Req Rewrite</display-name> <!-- Change to "Production" when you are ready to deploy --> <context-param> <param-name>javax.faces.PROJECT_STAGE</param-name> <param-value>Development</param-value> </context-param> <!-- JSF mapping --> <servlet> <servlet-name>FacesServlet</servlet-name> <servlet-class>javax.faces.webapp.FacesServlet</servlet-class> <load-on-startup>1</load-on-startup> </servlet> <!-- Map these files with JSF --> <servlet-mapping> <servlet-name>FacesServlet</servlet-name> <url-pattern>/faces/*</url-pattern> </servlet-mapping> <!-- Session timeout --> <session-config> <session-timeout>30</session-timeout> </session-config> <!-- Welcome page --> <welcome-file-list> <welcome-file>faces/index.xhtml</welcome-file> </welcome-file-list> <!-- Filters --> <filter> <filter-name>RewriteBodyTestFilter</filter-name> <filter-class>com.testwebapp.reqrewrite.filter.RewriteBodyTestFilter </filter-class> </filter> <!-- Filter mappings / chain ordering --> <filter-mapping> <filter-name>RewriteBodyTestFilter</filter-name> <servlet-name>FacesServlet</servlet-name> <dispatcher>REQUEST</dispatcher> <dispatcher>FORWARD</dispatcher> </filter-mapping> </web-app> pom.xml : ------------------------------------------------------------------------------------- <project xmlns="http://maven.apache.org/POM/4.0.0"; xmlns:xsi=" http://www.w3.org/2001/XMLSchema-instance"; xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd";> <modelVersion>4.0.0</modelVersion> <groupId>com.testwebapp.reqrewrite</groupId> <artifactId>reqrewrite</artifactId> <packaging>war</packaging> <version>1.0-SNAPSHOT</version> <name>reqrewrite Maven Webapp</name> <url>http://maven.apache.org</url> <dependencies> <dependency> <groupId>javax.servlet</groupId> <artifactId>javax.servlet-api</artifactId> <version>3.1.0</version> <scope>provided</scope> </dependency> <dependency> <groupId>org.apache.myfaces.core</groupId> <artifactId>myfaces-api</artifactId> <version>2.2.8</version> </dependency> <dependency> <groupId>org.apache.myfaces.core</groupId> <artifactId>myfaces-impl</artifactId> <version>2.2.8</version> </dependency> </dependencies> <build> <finalName>reqrewrite</finalName> </build> </project>
