Access-Control-Allow-Origin: * in tomcat

问题:

I want to set a default http header in my tomcat container -

Access-Control-Allow-Origin: *

From various different links on stackoverslow and from google, most have pointed to a resource. This again says same on how to do it. I have replicated the same, but still the header is not shown. This is what I have done: 1) Copied cors.jar file in /lib folder of tomcat 2) Inserted this text in web.xml

<filter>
    <filter-name>CORS</filter-name>
    <filter-class>com.thetransactioncompany.cors.CORSFilter</filter-class>
    <init-param>
     <param-name>cors.allowOrigin</param-name>
        <param-value>*</param-value>
    </init-param>
    <init-param>
     <param-name>cors.supportedMethods</param-name>
        <param-value>GET, POST, HEAD, PUT, DELETE</param-value>
    </init-param>
    <init-param>
     <param-name>cors.supportedHeaders</param-name>
        <param-value>Content-Type, Last-Modified</param-value>
    </init-param>
    <init-param>
        <param-name>cors.exposedHeaders</param-name>
        <param-value>Set-Cookie</param-value>
    </init-param>
    <init-param>
        <param-name>cors.supportsCredentials</param-name>
        <param-value>true</param-value>
    </init-param>
</filter>

<filter-mapping>
    <filter-name>CORS</filter-name>
    <url-pattern>/*</url-pattern>
</filter-mapping>

It doesn't work and I am helpless. My tomcat version is -6.0.6. Please help.

回答1:

At the time of writing this, the current version of Tomcat 7 (7.0.41) has a built-in CORS filter http://tomcat.apache.org/tomcat-7.0-doc/config/filter.html#CORS_Filter

回答2:

The issue arose because of not including jar file as part of the project. I was just including it in tomcat lib. Using the below in web.xml works now:

<filter>
    <filter-name>springSecurityFilterChain</filter-name>
    <filter-class>
        org.springframework.web.filter.DelegatingFilterProxy
    </filter-class>
</filter>

 <filter-mapping>
    <filter-name>springSecurityFilterChain</filter-name>
    <url-pattern>/*</url-pattern>
</filter-mapping>

<filter>
    <filter-name>CORS</filter-name>
    <filter-class>com.thetransactioncompany.cors.CORSFilter</filter-class>

    <init-param>
        <param-name>cors.allowOrigin</param-name>
        <param-value>*</param-value>
    </init-param>
    <init-param>
        <param-name>cors.supportsCredentials</param-name>
        <param-value>false</param-value>
    </init-param>
    <init-param>
        <param-name>cors.supportedHeaders</param-name>
        <param-value>accept, authorization, origin</param-value>
    </init-param>
    <init-param>
        <param-name>cors.supportedMethods</param-name>
        <param-value>GET, POST, HEAD, OPTIONS</param-value>
    </init-param>
</filter>


<filter-mapping>
    <filter-name>CORS</filter-name>
    <url-pattern>/*</url-pattern>
</filter-mapping>

And the below in your project dependency:

<dependency>
    <groupId>com.thetransactioncompany</groupId>
    <artifactId>cors-filter</artifactId>
    <version>1.3.2</version>
</dependency>

回答3:

Change this:

<init-param>
    <param-name>cors.supportedHeaders</param-name>
    <param-value>Content-Type, Last-Modified</param-value>
</init-param>

To this

<init-param>
    <param-name>cors.supportedHeaders</param-name>
    <param-value>Accept, Origin, X-Requested-With, Content-Type, Last-Modified</param-value>
</init-param>

I had to do this to get anything to work.

回答4:

Please check your web.xml again. You might be making some silly mistake. As my application is working fine with the same init-param configuration...

Please copy paste the web.xml, if the problem still persists.

回答5:

Try this.

1.write a custom filter

    package com.dtd.util;

    import javax.servlet.*;
    import javax.servlet.http.HttpServletResponse;
    import java.io.IOException;

    public class CORSFilter implements Filter {

        @Override
        public void init(FilterConfig filterConfig) throws ServletException {

        }

        @Override
        public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
            HttpServletResponse httpResponse = (HttpServletResponse) servletResponse;
            httpResponse.addHeader("Access-Control-Allow-Origin", "*");
            filterChain.doFilter(servletRequest, servletResponse);
        }

        @Override
        public void destroy() {

        }
    }

2.add to web.xml

<filter>
    <filter-name>CorsFilter</filter-name>
    <filter-class>com.dtd.util.CORSFilter</filter-class>
</filter>

<filter-mapping>
    <filter-name>CorsFilter</filter-name>
    <url-pattern>/*</url-pattern>
 </filter-mapping>

回答6:

I had to restart the browser after changing the ip address (laptop wireless DHCP) which was my "cross-host" I was referring to in my web app, which resolved the issue.

Also make sure all the cors headers being added by your browser/host are accepted/allowed by including then in the cors.allowed.headers