[Cache] MemcachedAdapter not working with TagAwareAdapter

wucdbm · nicolas-grekas · commit 405f64bb0143 · 2017-06-05T12:44:43.000+02:00
It seems that when MemcachedAdapter is used with TagAwareAdapter, it fails to fetch items, even though I thoroughly tested fetching items with the exact same keys under the same namespace.

Turns out the issue lies in `const TAGS_PREFIX = "\0tags\0";` for unknown to me reasons. Hardcoding that to '__tags__' in my project did the trick and I've been using it for a couple of days now and it seems fine.

The reason I had to completely copy/paste this file in my local project is self:: instead of static:: usage. I am not sure whether that is a mistake or is done on purpose, but in order to have this work for me I need to be able to override that constant. Going with static:: seems like a good solution to me, then I can set whatever prefix I need for the tags.
diff --git a/src/Symfony/Component/Cache/Adapter/AbstractAdapter.php b/src/Symfony/Component/Cache/Adapter/AbstractAdapter.php
@@ -426,6 +426,9 @@ private function generateItems($items, &$keys)
 
         try {
             foreach ($items as $id => $value) {
+                if (!isset($keys[$id])) {
+                    $id = key($keys);
+                }
                 $key = $keys[$id];
                 unset($keys[$id]);
                 yield $key => $f($key, $value, true);
diff --git a/src/Symfony/Component/Cache/Adapter/TagAwareAdapter.php b/src/Symfony/Component/Cache/Adapter/TagAwareAdapter.php
@@ -261,7 +261,7 @@ private function generateItems($items, array $tagKeys)
 
         foreach ($items as $key => $item) {
             if (!$tagKeys) {
-                yield $key => isset($invalidKeys[self::TAGS_PREFIX.$key]) ? $f($key, null, $item) : $item;
+                yield $key => isset($invalidKeys[static::TAGS_PREFIX.$key]) ? $f($key, null, $item) : $item;
                 continue;
             }
             if (!isset($tagKeys[$key])) {
@@ -287,7 +287,7 @@ private function generateItems($items, array $tagKeys)
                 $itemTags = $tagVersions = $tagKeys = null;
 
                 foreach ($bufferedItems as $key => $item) {
-                    yield $key => isset($invalidKeys[self::TAGS_PREFIX.$key]) ? $f($key, null, $item) : $item;
+                    yield $key => isset($invalidKeys[static::TAGS_PREFIX.$key]) ? $f($key, null, $item) : $item;
                 }
                 $bufferedItems = null;
             }

Original file line number	Diff line number	Diff line change
`@@ -261,7 +261,7 @@ private function generateItems($items, array $tagKeys)`
`261`	`261`
`262`	`262`	`foreach ($items as $key => $item) {`
`263`	`263`	`if (!$tagKeys) {`
`264`		`- yield $key => isset($invalidKeys[self::TAGS_PREFIX.$key]) ? $f($key, null, $item) : $item;`
	`264`	`+ yield $key => isset($invalidKeys[static::TAGS_PREFIX.$key]) ? $f($key, null, $item) : $item;`
`265`	`265`	`continue;`
`266`	`266`	`}`
`267`	`267`	`if (!isset($tagKeys[$key])) {`
`@@ -287,7 +287,7 @@ private function generateItems($items, array $tagKeys)`
`287`	`287`	`$itemTags = $tagVersions = $tagKeys = null;`
`288`	`288`
`289`	`289`	`foreach ($bufferedItems as $key => $item) {`
`290`		`- yield $key => isset($invalidKeys[self::TAGS_PREFIX.$key]) ? $f($key, null, $item) : $item;`
	`290`	`+ yield $key => isset($invalidKeys[static::TAGS_PREFIX.$key]) ? $f($key, null, $item) : $item;`
`291`	`291`	`}`
`292`	`292`	`$bufferedItems = null;`
`293`	`293`	`}`