Tomcat: getHeader("Host") vs. getServerName()
httprequest, java, tomcat
Solution
You need to ensure that `httpd` passes the `Host` header provided by the client to Tomcat. The easiest way (assuming you are using `mod_proxy_http` - you didn't say) is with the following:
ProxyPreserveHost On
Problem
I've got a Tomcat app that is being served up from multiple domains. Previous developers built a method to return the application URL (see below). In the method they request the server name (`request.getServerName()`) which, appropriately, returns the ServerName from the httpd.conf file. However, I don't want that. What I want is the host name that the browser sent the request to, i.e. whichever domain the browser is accessing the application from. I tried `getHeader("Host")`, but that is still returning the ServerName set in the httpd.conf file. Instead of `request.getServerName()`, what should I use to get the server name that the browser sent the request to? For example: - ServerName in httpd.conf: www.myserver.net - User accesses Tomcat app on www.yourserver.net I need to return www.yourserver.net NOT www.myserver.net. The `request.getServerName()` call only seems to return www.myserver.net ``` /** * Convenience method to get the application's URL based on request * variables. * * @param request the current request * @return URL to application */ public static String getAppURL(HttpServletRequest request) { StringBuffer url = new StringBuffer(); int port = request.getServerPort(); if (port < 0) { port = 80; // Work around java.net.URL bug } String scheme = request.getScheme(); url.append(scheme); url.append("://"); url.append(request.getServerName()); if (("http".equals(scheme) && (port != 80)) || ("https".equals(scheme) && (port != 443))) { url.append(':'); url.append(port); } url.append(request.getContextPath()); return url.toString(); } ``` Thanks in advance!