Migrating a site from a staging environment to production

Thank you very much for your response on this, agentrickard. I have something mostly up and running at this point though I ran into an issue - when I implemented hook_domainload and altered $domain['path'], it did not seem to do anything to the links. However, if I change $domain['subdomain'], the links on the subdomains with different sources do change appropriately (though I'm guessing that may be a somewhat harsher option to implement?).

Ah, that makes perfect sense :) Thank you very much!

I wrote out what you described and it looks to work perfectly. I'm posting the code here if it might be useful to others (the name of the module could use work but I tried to make it flexible enough for others to get potential use out of it):

domain_access_alias_redirect.info:

; $Id $
name = "Domain Alias Redirect"
description = "Provide domain redirection to an alias - useful for development/stage switches"
core = 6.x
package = Domain Access
dependencies[] = domain
dependencies[] = domain_alias

domain_access_alias_redirect.install:

<?php

/**
 * Implementation of hook_install().
 */
function domain_access_alias_redirect_install() {
  $domain_weight = max(0, db_result(db_query("SELECT weight FROM {system} WHERE name='domain'")));
  db_query("UPDATE {system} SET weight = %d WHERE name='domain_access_alias_redirect'", $domain_weight + 1);
}

/**
 * Implementation of hook_uninstall().
 */
function domain_access_alias_redirect_uninstall() {
  db_query("DELETE FROM {variable} WHERE name LIKE 'domain-access-alias-redirect-path%%'");
}

domain_access_alias_redirect.module:

<?php

/**
 * @file
 * Domain Access Alias Redirect primary module file
 * This module will let the user decide if a particular url is what will be used
 * instead of the main site domain.
 * This makes it useful for site migrations when you may want content to have a
 * staging domain url until move to a production site whereby you can then
 * change it to use the primary domain record, change to another alias, or uninstall
 * the module for core domain access functionality.
 */


/**
 * Implementation of hook_menu()
 */
function domain_access_alias_redirect_menu() {
  $items = array();
  
  $items['admin/build/domain/alias/redirect/path'] = array(
    'title' => 'Edit domain path',
    'description' => 'Alter the path of the domain - useful for content migration towards another domain.',
    'type' => MENU_LOCAL_TASK,
    'access arguments' => array('administer domains'),
    'page callback' => 'drupal_get_form',
    'page arguments' => array('domain_access_alias_redirect_path_form'),
    'file' => 'domain_access_alias_redirect.admin.inc',
  );
  
  return $items;
}

/**
 * Implementation of hook_domainload().
 */
function domain_access_alias_redirect_domainload(&$domain) {
  $new_domain_path = variable_get('domain-access-alias-redirect-path-'. $domain['domain_id'], $subdomain);
  // Save the original subdomain in case there are any issues
  $domain['original_subdomain'] = $subdomain;
  $domain['original_path'] = $domain['path'];
  if ($new_domain_path !== $domain['subdomain']) {
    if ($domain['path']) {
      $domain['path'] = str_replace($domain['subdomain'], $new_domain_path, $domain['path']);
    }
  }
}

domain_access_alias_redirect.admin.inc:

<?php

/**
 * Form to select the path generated for a particular site.
 */
function domain_access_alias_redirect_path_form($form_state) {
  $form = array();
  // Get list of domains.
  $domains = domain_domains();
  
  foreach ($domains as $domain_key => $domain) {
    $subdomain = ($domain['original_subdomain']) ? $domain['original_subdomain'] : $domain['subdomain'];
    $domain_paths = array($subdomain => $subdomain);
    foreach($domain['aliases'] as $domain_alias) {
      $domain_paths[$domain_alias['pattern']] = $domain_alias['pattern'];
    }
    $form['domain-access-alias-redirect-path-'. $domain['domain_id']] = array(
      '#type' => 'select',
      '#title' => t('Alias redirect for @subdomain', array('@subdomain' => $subdomain)),
      '#options' => $domain_paths,
      '#default_value' => variable_get('domain-access-alias-redirect-path-'. $domain['domain_id'], $subdomain),
    );
  }
  
  return system_settings_form($form);
}

Unless I missed something in the domain alias module, this one allows you to switch to using one of the aliases (changes the path for a domain) you create for the site (so if I have a site domain.com with the alias dev.domain.com and stage.domain.com, you can configure the module to use the dev.domain.com aliss the links on the other subdomains will come up as dev.domain.com). Its just building on top of what domain alias provides.