#43462 by c960657 and andypost: Fixed issues with certain configurations of compressed pages.

4 files changed, 45 insertions, 22 deletions

diff --git a/includes/bootstrap.inc b/includes/bootstrap.inc
index 746e99947..7ab4f2b65 100644
--- a/includes/bootstrap.inc
+++ b/includes/bootstrap.inc
@@ -1104,6 +1104,9 @@ function drupal_serve_page_from_cache(stdClass $cache) {
     header('Vary: Accept-Encoding', FALSE);
     // If page_compression is enabled, the cache contains gzipped data.
     if ($return_compressed) {
+      // $cache->data is already gzip'ed, so make sure zlib.output_compression
+      // does not compress it once more.
+      ini_set('zlib.output_compression', '0');
       header('Content-Encoding: gzip');
     }
     else {
diff --git a/includes/common.inc b/includes/common.inc
index fc1e71d29..ff2c81776 100644
--- a/includes/common.inc
+++ b/includes/common.inc
@@ -4322,13 +4322,13 @@ function _drupal_bootstrap_full() {
 /**
  * Store the current page in the cache.
  *
- * We try to store a gzipped version of the cache. This requires the
- * PHP zlib extension (http://php.net/manual/en/ref.zlib.php).
- * Presence of the extension is checked by testing for the function
- * gzencode. There are two compression algorithms: gzip and deflate.
- * The majority of all modern browsers support gzip or both of them.
- * We thus only deal with the gzip variant and unzip the cache in case
- * the browser does not accept gzip encoding.
+ * If page_compression is enabled, a gzipped version of the page is stored in
+ * the cache to avoid compressing the output on each request. The cache entry
+ * is unzipped in the relatively rare event that the page is requested by a
+ * client without gzip support.
+ *
+ * Page compression requires the PHP zlib extension
+ * (http://php.net/manual/en/ref.zlib.php).
  *
  * @see drupal_page_header
  */
@@ -4336,8 +4336,6 @@ function drupal_page_set_cache() {
   global $base_root;
 
   if (drupal_page_is_cacheable()) {
-    $cache_page = TRUE;
-
     $cache = (object) array(
       'cid' => $base_root . request_uri(),
       'data' => ob_get_clean(),
@@ -4353,19 +4351,10 @@ function drupal_page_set_cache() {
       $cache->headers[$header_names[$name_lower]] = $value;
     }
 
-    if (variable_get('page_compression', TRUE) && function_exists('gzencode')) {
-      // We do not store the data in case the zlib mode is deflate. This should
-      // be rarely happening.
-      if (zlib_get_coding_type() == 'deflate') {
-        $cache_page = FALSE;
-      }
-      elseif (zlib_get_coding_type() == FALSE) {
+    if ($cache->data) {
+      if (variable_get('page_compression', TRUE) && extension_loaded('zlib')) {
         $cache->data = gzencode($cache->data, 9, FORCE_GZIP);
       }
-      // The remaining case is 'gzip' which means the data is already
-      // compressed and nothing left to do but to store it.
-    }
-    if ($cache_page && $cache->data) {
       cache_set($cache->cid, $cache->data, 'cache_page', $cache->expire, $cache->headers);
     }
     return $cache;
diff --git a/modules/simpletest/drupal_web_test_case.php b/modules/simpletest/drupal_web_test_case.php
index 985d0c0bd..9b0bf7275 100644
--- a/modules/simpletest/drupal_web_test_case.php
+++ b/modules/simpletest/drupal_web_test_case.php
@@ -1516,7 +1516,7 @@ class DrupalWebTestCase extends DrupalTestCase {
    *   Either the new page content or FALSE.
    */
   protected function checkForMetaRefresh() {
-    if ($this->drupalGetContent() != '' && $this->parse()) {
+    if (strpos($this->drupalGetContent(), '<meta ') && $this->parse()) {
       $refresh = $this->xpath('//meta[@http-equiv="Refresh"]');
       if (!empty($refresh)) {
         // Parse the content attribute of the meta tag for the format:
diff --git a/modules/simpletest/tests/bootstrap.test b/modules/simpletest/tests/bootstrap.test
index b6bfd54e8..cac805897 100644
--- a/modules/simpletest/tests/bootstrap.test
+++ b/modules/simpletest/tests/bootstrap.test
@@ -91,7 +91,7 @@ class BootstrapPageCacheTestCase extends DrupalWebTestCase {
   public static function getInfo() {
     return array(
       'name' => 'Page cache test',
-      'description' => 'Enable the page cache and test it with conditional HTTP requests.',
+      'description' => 'Enable the page cache and test it with various HTTP requests.',
       'group' => 'Bootstrap'
     );
   }
@@ -177,6 +177,37 @@ class BootstrapPageCacheTestCase extends DrupalWebTestCase {
     $this->assertEqual($this->drupalGetHeader('Foo'), 'bar', t('Custom header was sent.'));
 
   }
+
+  /**
+   * Test page compression.
+   * 
+   * The test should pass even if zlib.output_compression is enabled in php.ini,
+   * .htaccess or similar, or if compression is done outside PHP, e.g. by the
+   * mod_deflate Apache module.
+   */
+  function testPageCompression() {
+    variable_set('cache', CACHE_NORMAL);
+
+    // Fill the cache and verify that output is compressed.
+    $this->drupalGet('', array(), array('Accept-Encoding: gzip,deflate'));
+    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'MISS', t('Page was not cached.'));
+    $this->drupalSetContent(gzinflate(substr($this->drupalGetContent(), 10, -8)));
+    $this->assertRaw('</html>', t('Page was gzip compressed.'));
+
+    // Verify that cached output is compressed.
+    $this->drupalGet('', array(), array('Accept-Encoding: gzip,deflate'));
+    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'HIT', t('Page was cached.'));
+    $this->assertEqual($this->drupalGetHeader('Content-Encoding'), 'gzip', t('A Content-Encoding header was sent.'));
+    $this->drupalSetContent(gzinflate(substr($this->drupalGetContent(), 10, -8)));
+    $this->assertRaw('</html>', t('Page was gzip compressed.'));
+
+    // Verify that a client without compression support gets an uncompressed page.
+    $this->drupalGet('');
+    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'HIT', t('Page was cached.'));
+    $this->assertFalse($this->drupalGetHeader('Content-Encoding'), t('A Content-Encoding header was not sent.'));
+    $this->assertTitle(t('Welcome to @site-name | @site-name', array('@site-name' => variable_get('site_name', 'Drupal'))), t('Site title matches.'));
+    $this->assertRaw('</html>', t('Page was not compressed.'));
+  }
 }
 
 class BootstrapVariableTestCase extends DrupalWebTestCase {