Issue #2823361 by stevector, David Strauss: Uncaught PHP Exception ca…

…used by long cache IDs

circle.yml

@@ -22,8 +22,8 @@ dependencies:
     - composer global require "hirak/prestissimo:^0.3"
     - composer global require drush/drush:8.*
     # @todo, composer is probably a bad/slow way to install core here.
-    # Use something like drush's 
-    - git clone --branch 8.1.x https://git.drupal.org/project/drupal.git $DOCROOT
+    # Use something like drush's
+    - git clone --branch 8.2.x https://git.drupal.org/project/drupal.git $DOCROOT
     - cd $DOCROOT && composer install
     # Add apache config.
     # Modify user to make sure that there will be no permission issues.
@@ -66,7 +66,7 @@ test:
   override:
     - ./vendor/bin/phpcs --report=full --extensions=php,module,inc,theme,info --standard=vendor/drupal/coder/coder_sniffer/Drupal/ --ignore=vendor .
     - cd $DOCROOT && /home/ubuntu/.phpenv/shims/php  core/scripts/run-tests.sh  --url  $SERVER  --module lcache    --php  /home/ubuntu/.phpenv/shims/php --verbose  --color
-    
+
 deployment:
   feature:
     branch: 8.x-1.x

src/Backend.php

@@ -46,6 +46,7 @@ public function __construct($bin, \LCache\Integrated $integrated) {
    *   The Cache ID.
    */
   protected function getAddress($cid) {
+    $cid = $this->normalizeCid($cid);
     return new \LCache\Address($this->bin, $cid);
   }
 
@@ -203,4 +204,35 @@ public function garbageCollection() {
   public function isEmpty() {
     return FALSE;
   }
+
+  /**
+   * Normalizes a cache ID in order to comply with database limitations.
+   *
+   * @param string $cid
+   *   The passed in cache ID.
+   *
+   * @return string
+   *   An ASCII-encoded cache ID that is limited in length.
+   */
+  protected function normalizeCid($cid) {
+    $cid_is_ascii = mb_check_encoding($cid, 'ASCII');
+
+    // 508 is the max length of the address column (512) minus
+    // the number of characters that will be added to the stored address value
+    // by Address::serialze() when the bin length is long (two digits).
+    $max_cid_length = 508 - strlen($this->bin);
+    if (strlen($cid) <= $max_cid_length && $cid_is_ascii) {
+      return $cid;
+    }
+
+    // Return a string that uses as much as possible of the original cache ID
+    // with the hash appended.
+    // Cut the hash in half to allow for more storage of the real cid's length
+    // to be stored.
+    $hash = substr(hash('sha512', $cid), 0, 64);
+    if (!$cid_is_ascii) {
+      return $hash;
+    }
+    return substr($cid, 0, $max_cid_length - strlen($hash)) . $hash;
+  }
 }

src/Tests/BackendUnitTest.php

@@ -275,4 +275,29 @@ public function testInvalidate() {
     $this->assertFalse($backend->invalidateMultiple(array()));
   }
   // @codingStandardsIgnoreEnd
+
+  /**
+   * Test \Drupal\lcache\Backend::normalizeCids().
+   */
+  public function testSetGetLong() {
+
+    $backend = $this->getCacheBackend();
+
+    // Set up a cache ID that is not ASCII and longer than 255 characters so we
+    // can test cache ID normalization.
+    $cid_long = str_repeat('愛€', 1000);
+    $cached_value_long = $this->randomMachineName();
+    $backend->set($cid_long, $cached_value_long);
+    $this->assertIdentical($cached_value_long, $backend->get($cid_long)->data, "Backend contains the correct value for long, non-ASCII cache id.");
+
+    $cid_long = str_repeat('abcdefghijk', 100);
+    $cached_value_long = $this->randomMachineName();
+    $backend->set($cid_long, $cached_value_long);
+    $this->assertIdentical($cached_value_long, $backend->get($cid_long)->data, "Backend contains the correct value for long, non-ASCII cache id.");
+
+    $cid_short = '愛1€';
+    $cached_value_short = $this->randomMachineName();
+    $backend->set($cid_short, $cached_value_short);
+    $this->assertIdentical($cached_value_short, $backend->get($cid_short)->data, "Backend contains the correct value for short, non-ASCII cache id.");
+  }
 }