.htaccess

Options +FollowSymLinks
IndexIgnore */*
RewriteEngine on

# Если запрос начинается с /admin, то заменяем на /backend/web/
RewriteCond %{REQUEST_URI} ^/admin
RewriteRule ^admin\/?(.*) /backend/web/$1
 
# Добавляем другой запрос /frontend/web/$1
RewriteCond %{REQUEST_URI} !^/(frontend/web|backend/web|admin)
RewriteRule (.*) /frontend/web/$1
 
# Если frontend запрос
RewriteCond %{REQUEST_URI} ^/frontend/web
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /frontend/web/index.php
 
# Если backend запрос
RewriteCond %{REQUEST_URI} ^/backend/web
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /backend/web/index.php

Header add Access-Control-Allow-Origin "*"
Header add Access-Control-Allow-Headers "origin, x-requested-with, content-type"
Header add Access-Control-Allow-Methods "PUT, GET, POST, DELETE, OPTIONS"

#Added a rewrite to respond with a 200 SUCCESS on every OPTIONS request.
#RewriteEngine On
#RewriteCond %{REQUEST_METHOD} OPTIONS
#RewriteRule ^(.*)$ $1 [R=200,L]