php: add proxy module

web/documentserver-example/php/composer.json

@@ -12,6 +12,7 @@
             "Example\\Common\\": "src/common/",
             "Example\\Configuration\\" : "src/configuration/",
             "Example\\Helpers\\" : "src/helpers/",
+            "Example\\Proxy\\": "src/proxy/",
             "Example\\Views\\" : "src/views/"
         }
     }

web/documentserver-example/php/src/proxy/ProxyManager.php

@@ -0,0 +1,63 @@
+<?php
+//
+// (c) Copyright Ascensio System SIA 2023
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+namespace Example\Proxy;
+
+use Example\Common\URL;
+use Example\Configuration\ConfigurationManager;
+
+class ProxyManager
+{
+    public ConfigurationManager $configManager;
+
+    public function __construct(ConfigurationManager $configManager)
+    {
+        $this->configManager = $configManager;
+    }
+
+    public function resolveURL(URL $url): URL
+    {
+        if (!$this->referPublicURL($url)) {
+            return $url;
+        }
+        return $this->redirectPublicURL($url);
+    }
+
+    private function referPublicURL(URL $url): bool
+    {
+        $public_url = $this->configManager->document_server_public_url();
+        return
+            $url->scheme() == $public_url->scheme() &&
+            $url->host() == $public_url->host() &&
+            $url->port() == $public_url->port();
+    }
+
+    private function redirectPublicURL(URL $url): URL
+    {
+        $private_url = $this->configManager->document_server_private_url();
+        return URL::from_components(
+            $private_url->scheme(),
+            $private_url->host(),
+            $private_url->port(),
+            $url->user(),
+            $url->pass(),
+            $url->path(),
+            $url->query(),
+            $url->fragment()
+        );
+    }
+}