mod rewrite - Apache / mod_rewrite: Change TLD, but keep subdomain, protocol and query-string -

i thoroughly searched stackoverflow , found 100 mod_rewrite-questions, not covered...strange seems pretty common.

my problem: have web-application on master-domain (mywebapp.com). have additional country-specific tlds (eg .ch) i'd redirect on .com-domain. nothing special far. other criteria:

requirements

• the protocol should left unchanged
• the query-string should left unchanged
• the subdomain-part should left unchanged tenants identified those
• only exchange tld!

examples

so put examples how should be:

• http:// demo.mywebapp.ch -> http:// demo.mywebapp.com
• http:// other.mywebapp.ch/user/profile -> http:// other.mywebapp.com/user/profile
• https:// third.mywebapp.ch/about -> https:// third.mywebapp.com/about

(spaces in urls intentional prevent stackoverflow generating links)

and on. need replace tld in protocol-generic manner. of course nice if rule-set seo-conform (301).

additional information / details

the domains set point same webserver/ip have root-access upon. server managed ispconfig, ii can edit vhosts manually well.

thanks in advance!

cheers, pascal

i think following trick:

rewriteengine on rewritebase /  rewritecond %{http_host} !.*\.com rewritecond %{https} ^on rewritecond %{http_host} (?:([^.]+)\.)?mywebapp\..* rewriterule ^.* https://%1mywebapp.com%{request_uri} [r=302,l] #removed double slash  rewritecond %{http_host} !.*\.com rewritecond %{https} !^on rewritecond %{http_host} (?:([^.]+)\.)?mywebapp\..* rewriterule ^.* http://%1mywebapp.com%{request_uri} [r=302,l] #removed double slash 

here's it's saying:

1. create rewriterule only if %{http_host} not contain .com
2. check protocol , continue if https
3. run regex check if subdomain exists , store subdomain if (referenced $1)
4. manually force .com, preceed subdomain, concatenate %{request_uri} , redirect (i left 302 temporary redirect can play needed. go 301 until 100% ready)

edit: duplicated rule set handle protocol issue. apparently can last backreference. meaning when protocol https, overwrite subdomain stored in %1 backreference. having ruleset either protocol, circumvent issue. not prettiest way, should job done.