title: Dynamic query parameters for the authorization request
body: <p>Hello I want to configure <code>apache2</code> server to redirect unauthorized user to my provider login page such as <code>google</code>, <code>gluu</code> and etc.. I'm using <code>mod_auth_openidc</code> and the below code snippet my <code>default-ssl.conf</code> file</p>
  
  <pre><code>&lt;IfModule mod_ssl.c&gt;
      &lt;VirtualHost _default_:8443&gt;
          OIDCProviderMetadataURL https://&lt;my_provider&gt;/.well-known/openid-configuration
          OIDCClientID &lt;client_code&gt;
          OIDCClientSecret &lt;client_secret&gt;
          OIDCRedirectURI https://&lt;my_site&gt;:8443/cgi-bin/
          #OIDCAuthRequestParams acr_values=auth_request_params
          OIDCResponseType code
          OIDCScope "openid profile email"
          OIDCSSLValidateServer Off
          OIDCCryptoPassphrase 123456
          OIDCPassClaimsAs environment
          OIDCClaimPrefix USERINFO_
          OIDCPassIDTokenAs payload
          &lt;Location "/"&gt;
              Require valid-user
              AuthType openid-connect
          &lt;/Location&gt;
  
  
          ServerAdmin webmaster@localhost
  
          DocumentRoot /var/www/html
  
          ErrorLog ${APACHE_LOG_DIR}/error.log
          CustomLog ${APACHE_LOG_DIR}/access.log combined
  
          SSLEngine on
  
          SSLCertificateFile /etc/apache2/ssl/apache.crt
          SSLCertificateKeyFile /etc/apache2/ssl/apache.key
  
          &lt;FilesMatch "\.(cgi|shtml|phtml|php)$"&gt;
                  SSLOptions +StdEnvVars
          &lt;/FilesMatch&gt;
          &lt;Directory /usr/lib/cgi-bin&gt;
                  SSLOptions +StdEnvVars
          &lt;/Directory&gt;
      &lt;/VirtualHost&gt;
  &lt;/IfModule&gt;
  </code></pre>
  
  <p>Now with this configuration eveything is ok. When I enter my site apache redirect me to the OP login page. I have 3 kind of authentication mechanism  and my provider decided which login page must be loading depend on <code>acr_values</code> and for display language from <code>ui_locales</code> param from the request. To do this I should pass this params to auth requset url. But with <code>mod_auth_openidc</code> I could not do. I can set <code>OIDCAuthRequestParams</code> statically but this not solve my problem because the login mechanism and language depend on user's choice. </p>
  
  <p>I read <a href="https://github.com/pingidentity/mod_auth_openidc/wiki#13-how-can-i-add-custom-parameters-to-the-authorization-request" rel="nofollow noreferrer">this documentation</a> and use the below link. But it does not work. I don't know may be I misunderstand something.</p>
  
  <blockquote>
    <p>[my_site]?target_link_uri=[my_site/mypage.html]&amp;iss=[my_provider]&amp;auth_request_params=[urlencoded-query-string]</p>
  </blockquote>
  
  <p>Is that wrong? How can I pass dynamic <code>acr_values</code> and <code>ui_locales</code> so that apache generate the auth request with these query parameters</p>