Can I rewrite a URL, adding query params and preserve the form data?

Question

I have a rule like:

RewriteCond %{HTTP_HOST}:%{QUERY_STRING} ^(\w+)\.t(.*)\.(\w+)?\.sprawk\.com:(.*)$
RewriteRule ^(.*) /api/translateHtmlPublic?tl=%1&su=%2&p=$1&q=%4 [B,PT,L]

which works great for GET requests.

However, for POST requests, the q parameter is null (which I expected) but inside my Java servlet, both the HttpServletRequest.getReader() and HttpServletRequest.getInputStream() give no data.

Using Firefox Live headers, I see that I am sending:

POST /uid/contactSend.cfm HTTP/1.1
Host: fr.t51940.local.sprawk.com
Connection: keep-alive
Referer: http://fr.t51940.local.sprawk.com/uid/contact.cfm?country=137
Cache-Control: max-age=0
Content-Type: application/x-www-form-urlencoded
Content-Length: 146
userName=Nic&queryCountry=Libya&queryCode=137&userEmail=n.cottrell%40idea.int&Comment=Just+testing&captcha=Quotas&Submit=--+Envoyer+Commentaire+--

I know that the servlet is receiving it as a POST since the doPost method is triggered. I understand that Apache 2.x should automatically preserve POST data during a simple rewrite, but maybe the addition of parameters is wiping the content data?

Update: I just realised (by dumping out all parameters) that the userName, queryCountry, queryCode parameters are getting correct values via the request.getParameter(String) method. The problem is that I need to be able to separate the original form parameter names from the ones I introduction in the RewriteRule.

Answer 1

1. The parameters of a POST are in the body, not the header. You can rewrite the URL as much as you like without affecting them.

2. The body of a POST request whose content type is application/x-www-form-urlencoded consists only of parameters that are retrieved via request.getParameter(). Reading the body via request.getInputStream() and request.getReader() will deliver nothing. (Servlet Specification 3, #3.1.1)

3. According to Servlet Specifcation #3, the parameters you add to the URL should be retrievable via getParameter() .

4. There is no way to distinguish POST parameters in the body from URL parameters in the header. There is probably therefore something wrong with your solution, or your problem.