How to get list of all cached items by key in Lara

问题:

The Cache class in laravel has methods such as get('itemKey') to retrieve items from the cache, and remember('itemKey', ['myData1', 'myData2']) to save items in the cache.

There is also a method to check if an item exists in the cache: Cache::has('myKey');

Is there any way, (when using the file-based cache driver), to get a list of all items in the cache?

For instance, something that might be named something like "Cache::all()" that would return:

[
    'itemKey' => [
        'myData1',
        'myData2'
   ],
   'myKey' => 'foo'
]

The only way I can think of doing this is to loop through all possible key names using the Cache::has() method. i.e. aaa, aab, aac, aad... but of course, this is not a solution.

I can't see anything in the documentation or the API that describes a function like this, but I don't think its unreasonable to believe that one must exist.

回答1:

There is no way to do that using Cache facade. Its interface represents the functionality that all underlying storages offer and some of the stores do not allow listing all keys.

If you're using the FileCache, you could try to achieve that by interacting with the underlying storage directly. It doesn't offer the method you need, so you'll need to iterate through the cache directory. It won't be too efficient due to a lot of disk I/O that might need to happen.

In order to access the storage, you need to do

$storage = Cache::getStore(); // will return instance of FileStore
$filesystem = $storage->getFilesystem(); // will return instance of Filesystem

$keys = [];
foreach ($filesystem->allFiles('') as $file1) {
  foreach ($filesystem->allFiles($file1) as $file2) {
    $keys = array_merge($keys, $filesystem->allFiles($file1 . '/' . $file2));
  }
}

回答2:

^This above dont work in LV 5.2

Try this solution:

    $storage = \Cache::getStore(); // will return instance of FileStore
    $filesystem = $storage->getFilesystem(); // will return instance of Filesystem
    $dir = (\Cache::getDirectory());
    $keys = [];
    foreach ($filesystem->allFiles($dir) as $file1) {

        if (is_dir($file1->getPath())) {

            foreach ($filesystem->allFiles($file1->getPath()) as $file2) {
                $keys = array_merge($keys, [$file2->getRealpath() => unserialize(substr(\File::get($file2->getRealpath()), 10))]);
            }
        }
        else {

        }
    }

回答3:

In 'yourKeyGoesHere' you can insert a string used as same as a like with a * or insert directly the exactly key.

 $redis = Cache::getRedis();
 $a_keys = $redis->keys("*yourKeyGoesHere*");
 foreach ($a_keys as $key){
    //Your Action ...
    //For example forget key
    $redis->del($key);
 }

回答4:

For Memcached, you can do this:

cache()->getMemcached()->getAllKeys()

1. get Illuminate\Cache\CacheManager
2. Get Memcached: http://php.net/manual/de/class.memcached.php
3. getAllKeys(): http://php.net/manual/de/memcached.getallkeys.php

This gives you an array of keys you can go through.