CRM-20821 - Use smarter logic to adjust img URL

This change is the crux of CRM-20821.

Before this change, editing a premium product would automatically
break the image URL. After this change, premium products can be edited
while retaining the image URL. Functionality is preserved which changes
the URL to a local URL when possible.

This commit adds two new Utils functions (along with tests) to handle
the logic of changing a supplied URL to a local URL.

CRM/Contribute/BAO/ManagePremiums.php

@@ -106,15 +106,9 @@ public static function add(&$params, &$ids) {
     );
     $params = array_merge($defaults, $params);
 
-    // CRM-14283 - strip protocol and domain from image URLs
-    $image_type = array('image', 'thumbnail');
-    foreach ($image_type as $key) {
-      if (isset($params[$key]) && $params[$key]) {
-        $parsedURL = explode('/', $params[$key]);
-        $pathComponents = array_slice($parsedURL, 3);
-        $params[$key] = '/' . implode('/', $pathComponents);
-      }
-    }
+    // Use local URLs for images when possible
+    $params['image'] = CRM_Utils_String::simplifyURL($params['image'], TRUE);
+    $params['thumbnail'] = CRM_Utils_String::simplifyURL($params['thumbnail'], TRUE);
 
     // Save and return
     $premium = new CRM_Contribute_DAO_Product();

CRM/Utils/String.php

@@ -789,6 +789,80 @@ public static function unstupifyUrl($htmlUrl) {
     return str_replace('&', '&', $htmlUrl);
   }
 
+  /**
+   * When a user supplies a URL (e.g. to an image), we'd like to:
+   *  - Remove the protocol and domain name if the URL points to the current
+   *    site.
+   *  - Keep the domain name for remote URLs.
+   *  - Optionally, force remote URLs to use https instead of http (which is
+   *    useful for images)
+   *
+   * @param string $url
+   *   The URL to simplify. Examples:
+   *     "https://example.org/sites/default/files/coffee-mug.jpg"
+   *     "sites/default/files/coffee-mug.jpg"
+   *     "http://i.stack.imgur.com/9jb2ial01b.png"
+   * @param bool $forceHttps = FALSE
+   *   If TRUE, ensure that remote URLs use https. If a URL with
+   *   http is supplied, then we'll change it to https.
+   *   This is useful for situations like showing a premium product on a
+   *   contribution, because (as reported in CRM-14283) if the user gets a
+   *   browser warning like "page contains insecure elements" on a contribution
+   *   page, that's a very bad thing. Thus, even if changing http to https
+   *   breaks the image, that's better than leaving http content in a
+   *   contribution page.
+   *
+   * @return string
+   *   The simplified URL. Examples:
+   *     "/sites/default/files/coffee-mug.jpg"
+   *     "https://i.stack.imgur.com/9jb2ial01b.png"
+   */
+  public static function simplifyURL($url, $forceHttps = FALSE) {
+    $config = CRM_Core_Config::singleton();
+    $siteURLParts = self::simpleParseUrl($config->userFrameworkBaseURL);
+    $urlParts = self::simpleParseUrl($url);
+
+    // If the image is locally hosted, then only give the path to the image
+    $urlIsLocal
+      = ($urlParts['host+port'] == '')
+      | ($urlParts['host+port'] == $siteURLParts['host+port']);
+    if ($urlIsLocal) {
+      // and make sure it begins with one forward slash
+      return preg_replace('_^/*(?=.)_', '/', $urlParts['path+query']);
+    }
+
+    // If the URL is external, then keep the full URL as supplied
+    else {
+      return $forceHttps ? preg_replace('_^http://_', 'https://', $url) : $url;
+    }
+  }
+
+  /**
+   * A simplified version of PHP's parse_url() function.
+   *
+   * @param string $url
+   *   e.g. "https://example.com:8000/foo/bar/?id=1#fragment"
+   *
+   * @return array
+   *   Will always contain keys 'host+port' and 'path+query', even if they're
+   *   empty strings. Example:
+   *   [
+   *     'host+port' => "example.com:8000",
+   *     'path+query' => "/foo/bar/?id=1",
+   *   ]
+   */
+  public static function simpleParseUrl($url) {
+    $parts = parse_url($url);
+    $host = isset($parts['host']) ? $parts['host'] : '';
+    $port = isset($parts['port']) ? ':' . $parts['port'] : '';
+    $path = isset($parts['path']) ? $parts['path'] : '';
+    $query = isset($parts['query']) ? '?' . $parts['query'] : '';
+    return array(
+      'host+port' => "$host$port",
+      'path+query' => "$path$query",
+    );
+  }
+
   /**
    * Formats a string of attributes for insertion in an html tag.
    *

tests/phpunit/CRM/Utils/StringTest.php

@@ -227,4 +227,140 @@ public function testFilterByWildCards($patterns, $expectedResults) {
     $this->assertEquals(array_merge($expectedResults, array('noise')), $actualResults);
   }
 
+  /**
+   * CRM-20821
+   * CRM-14283
+   *
+   * @param string $imageURL
+   * @param book $forceHttps
+   * @param string $expected
+   *
+   * @dataProvider simplifyURLProvider
+   */
+  public function testSimplifyURL($imageURL, $forceHttps, $expected) {
+    $this->assertEquals(
+      $expected,
+      CRM_Utils_String::simplifyURL($imageURL, $forceHttps)
+    );
+  }
+
+  /**
+   * Used for testNormalizeImageURL above
+   *
+   * @return array
+   */
+  public function simplifyURLProvider() {
+
+    $config = CRM_Core_Config::singleton();
+    $localDomain = parse_url($config->userFrameworkBaseURL)['host'];
+    $externalDomain = 'example.org';
+
+    // Ensure that $externalDomain really is different from $localDomain
+    if ($externalDomain == $localDomain) {
+      $externalDomain = 'example.net';
+    }
+
+    return array(
+
+      'prototypical example' =>
+      array(
+        "https://$localDomain/sites/default/files/coffee-mug.jpg",
+        FALSE,
+        '/sites/default/files/coffee-mug.jpg',
+      ),
+
+      'external domain with https' =>
+      array(
+        "https://$externalDomain/sites/default/files/coffee-mug.jpg",
+        FALSE,
+        "https://$externalDomain/sites/default/files/coffee-mug.jpg",
+      ),
+
+      'external domain with http forced to https' =>
+      array(
+        "http://$externalDomain/sites/default/files/coffee-mug.jpg",
+        TRUE,
+        "https://$externalDomain/sites/default/files/coffee-mug.jpg",
+      ),
+
+      'external domain with http not forced' =>
+      array(
+        "http://$externalDomain/sites/default/files/coffee-mug.jpg",
+        FALSE,
+        "http://$externalDomain/sites/default/files/coffee-mug.jpg",
+      ),
+
+      'local URL' =>
+      array(
+        "/sites/default/files/coffee-mug.jpg",
+        FALSE,
+        "/sites/default/files/coffee-mug.jpg",
+      ),
+
+      'local URL without a forward slash' =>
+      array(
+        "sites/default/files/coffee-mug.jpg",
+        FALSE,
+        "/sites/default/files/coffee-mug.jpg",
+      ),
+
+      'empty input' =>
+      array(
+        '',
+        FALSE,
+        '',
+      ),
+    );
+  }
+
+  /**
+   * @param string $url
+   * @param array $expected
+   *
+   * @dataProvider parseURLProvider
+   */
+  public function testSimpleParseUrl($url, $expected) {
+    $this->assertEquals(
+      $expected,
+      CRM_Utils_String::simpleParseUrl($url)
+    );
+  }
+
+  /**
+   * Used for testSimpleParseUrl above
+   *
+   * @return array
+   */
+  public function parseURLProvider() {
+    return array(
+
+      "prototypical example" =>
+      array(
+        "https://example.com:8000/foo/bar/?id=1#fragment",
+        array(
+          'host+port' => "example.com:8000",
+          'path+query' => "/foo/bar/?id=1",
+        ),
+      ),
+
+      "empty" =>
+      array(
+        "",
+        array(
+          'host+port' => "",
+          'path+query' => "",
+        ),
+      ),
+
+      "path only" =>
+      array(
+        "/foo/bar/image.png",
+        array(
+          'host+port' => "",
+          'path+query' => "/foo/bar/image.png",
+        ),
+      ),
+    );
+  }
+
 }