htaccess redirect root to subdirectory but allow index.php in root AND query strings to function

Question

I had a question similar to this, and it was answered. However, the answer led to another concept and now I have the following question. (User "anubhava" was able to answer the original question.)

Let me explain, our situation is this:

We are launching a new website using Joomla, however, we wanted all of the old website's in-bound links to continue to function (as we have a lot of content in WordPress on the old website). So, using htaccess, we were able to have all requests to the primary domain name redirect to a sub-directory with the new Joomla website in it. [So as an example, requests for www.example.com get redirected to www.example.com/PORTALsite due to the htaccess code, which is what we want.]

Further, this code also allows for requests to the Home page of the old WordPress website to still function (the old website we are replacing). [So as an example, www.example.com/index.php will still function and load the old WordPress site, which is what we want.]

Only if the request is for the domain name alone (www.example.com) will it redirect to the new Joomla website's Home page (located at www.example.com/PORTALsite/), but if the request is for the old website's Home page (located at www.example.com/index.php) it will allow this and load the old WordPress website.

Here's the htaccess code:

RewriteEngine on
RewriteCond %{THE_REQUEST} ^[A-Z]{3,}\s/+[\s?]
RewriteRule ^$ /PORTALsite [R=301,L]

HOWEVER, my problem now is this : There are many in-bound links where the old WordPress website's index.php page is omitted and only a query string is attached (indicating a Page name on the old website via WordPress). However, because the code above sees this as a call just to the primary domain name alone (as it "ignores" the query string) it also redirects this to the new Joomla website. We do not want this to happen ! Any help, please?

Example of what the problem is now :

1. (not a problem) requests for the primary domain name are successfully redirected to the new Jooma website, thus www.example.com will redirect to www.example.com/PORTALsite, as we want and as it should.

2. (not a problem) www.example.com/index.php successfully loads the old WordPress website's Home page though, as we want and as it should.

3. however this is the problem : in-bound links that have no file name but include a query string, such as www.example.com/?page_id=56 are also getting redirected to the new Joomla website (for example, www.example.com/PORTALsite/?page_id=56) AND WE DO NOT WANT THIS TO HAPPEN.

   we want www.example.com/?page_id=56 to redirect to www.example.com/index.php?page_id=56 and load the content from the old WordPress site. how do I make this happen based upon the htaccess code above?

Thanks in advance for any help!

Answer 1

RewriteEngine on
# Match requests for /
RewriteCond %{THE_REQUEST} ^[A-Z]{3,}\s/+[\s?]
# Don't match requests for page_id=n
RewriteCond %{QUERY_STRING} !page_id=[0-9]+
# Redirect to /PORTALsite
RewriteRule ^$ /PORTALsite [R=301,L]