Apache HttpClient 4.5 cross host redirect - apache-httpclient-4.x

Question

Here is my scenario
I am calling a url from HOSTA
http://www.hosta.com/something
This is redirecting me to the HOSTB url
http://www.hostb.com/something
This is response code which I gets from url a
http-outgoing-5 << HTTP/1.1 302 Moved Temporarily
http-outgoing-5 << Location: www.hostb.com/something
Redirecting to www.hostb.com/something
http-outgoing-10 >> Host: hosta.com
In the last line I see the host header is set to HOSTA which is wrong.
Here is the code I am using
This is how connection is created
private PoolingHttpClientConnectionManager cm = new PoolingHttpClientConnectionManager();
HttpClientBuilder builder= HttpClients.custom();
builder.setMaxConnPerRoute(50)
.setConnectionManager(cm)
.setConnectionTimeToLive(timeout, TimeUnit.MILLISECONDS)
.setDefaultCookieStore(cookieStore)
.setRedirectStrategy(new LaxRedirectStrategy())
.setDefaultSocketConfig(socketConfig)
.setServiceUnavailableRetryStrategy(retryStrategy)
.setKeepAliveStrategy(keepAliveStrategy)
.setRetryHandler(myRetryHandler);
Method to call the request
HttpPost post = new HttpPost(url);
post.setHeader("User-Agent", USER_AGENT);
post.setHeader("Cache-Control", "max-age=0");
post.setHeader("Connection", "keep-alive");
post.setHeader("Content-Type", "application/x-www-form-urlencoded");
post.setHeader("Upgrade-Insecure-Requests", "1");
post.setConfig(requestConfig);
if (origin != null) {
post.setHeader("Origin", origin);
}
if (host != null) {
post.setHeader("Host", host);
}
if (referer != null) {
post.setHeader("Referer", referer);
}
//some more code
I am using the automatic redirection (using LaxDirectStrategy) which are working fine. But in this particular case I am getting issue.
is there any way to update the HOST header in case of cross host redirect or automatic redirection can be stopped for one particular request?

Answer 1

I used the RequestConfig to disable/enable the redirection for particular request.
By Default I have redirection enabled.Whenever I wanted it to disable I used
RequestConfig requestConfig = RequestConfig.custom()
.setRedirectsEnabled(false).build();//disable redirect
HttpPost post = new HttpPost(url);
post.setConfig(requestConfig);//poass the request config to request

Answer 2

I faced similar issue with HttpClient 4.5.9 (and 4.5.13 too). It turned out that I was inadvertently writing the Host header.
HttpClient keeps the Host header if it is already defined in a request.
From Oleg Kalnichevski :
One ought not mess with HTTP transport headers such as 'Host' (...) and let HttpClient generate the appropriate header values instead.(...) As far as the 'Host' header is concerned HttpClient simply does not overwrite the existing value assuming that the user knows better.
Oleg
Reference: in case of a redirect a wrong host param is set to http header