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Redis Configure Laravel Cache

January 1, 2021 by Areg Sarkissian

This post is part of the Get Started with Production Ready Laravel series of posts.

In this post I will detail the steps to take to configure the Laravel caching API to use a Redis server running in a local docker for caching data development.

Out of the box Laravel use file based caching by default.

Steps to configure Laravel to use Redis for caching

To start, go to the root of your Laravel project then follow steps below:

Step 1 - Install the Laravel Redis driver

Refer to step 1 in Redis Configure Laravel to perform this step

Step 2 - Setup the Redis sever docker service

Refer to step 1 in Redis Configure Laravel to perform this step

Step 3 - Set the connection settings for the docker Redis service

Refer to step 2 in Redis Configure Laravel to perform this step

Step 4 - Configure the Redis driver settings

Refer to step 4 in Redis Configure Laravel to perform this step

Step 5 - Renaming the Cache Driver setting in the .env file

Open the .env file and rename the CACHE_DRIVER setting to CACHE_STORE to accurately reflect that it is selecting one of the available cache stores from the stores array in config/cache.php.

Before:

#incorrectly named environment variable that selects the cache store
CACHE_DRIVER=file

After:

#correctly named environment variable that selects the cache store
CACHE_STORE=file

Step 6 - Renaming the Cache Driver setting in the cache.php file

Open the config/cache.php file and rename the CACHE_DRIVER variable to CACHE_STORE.

The relevant snippet from config/cache.php file is shown below:

Before:

    //Default Cache Store used by laravel caching funcions
    //Misnamed env var that selects the cache store (not cache driver)from the Cache Stores array below
    'default' => env('CACHE_DRIVER', 'file'),
    'stores' => [
        //this is the 'file' cache store selected by the 'default' setting above when CACHE_DRIVER=file in .env file or by the second argument when no key is specified
        'file' => [
                'driver' => 'file', //this is the actual cache driver which is not what is being selected
                'path' => storage_path('framework/cache/data'),
            ],
        'redis' => [
                'driver' => 'redis', //the actual cache driver for the 'redis' store
                'connection' => 'cache',//the redis connection setting as specified in the config/database.php file
                'lock_connection' => 'default',
            ],
    ]

After:

    //Default Cache Store used by laravel caching funcions
    //Selects the file cache store from the cache 'stores' array below using correctly named CACHE_STORE env setting
    'default' => env('CACHE_STORE', 'file'),
    'stores' => [
        //this is the 'file' cache store selected by the 'default' setting above when CACHE_STORE=file in .env file or by the second argument when no key is specified
        'file' => [
                'driver' => 'file', //the actual cache driver for the 'file' store
                'path' => storage_path('framework/cache/data'),
            ],
        'redis' => [
                'driver' => 'redis', //the actual cache driver for the 'redis' store
                'connection' => 'cache',//the redis connection setting as specified in the config/database.php file
                'lock_connection' => 'default',
            ],
    ]

Step 7 - Updating the CACHE_STORE setting to use the redis store

Update the CACHE_STORE setting in the .env file to redis.

Before:

#correctly named environment variable that selects the cache store
CACHE_STORE=file

After:

#correctly named environment variable that selects the cache store
CACHE_STORE=redis

The setting value is used by the default setting in config/cache.php file to select the redis store.

Step 8 - Updating the default argument of the env helper

For the default setting in the config/cache.php file, update the default argument of the env() helper to redis.

Before:

    //Default Cache Store used by laravel caching funcions
    //Selects the file cache store from the cache 'stores' array below using correctly named CACHE_STORE env setting
    'default' => env('CACHE_STORE', 'file'),

After:

    //Default Cache Store used by laravel caching funcions
    //Selects the cache redis store from the Cache Stores array below using correctly named CACHE_STORE setting
    'default' => env('CACHE_STORE', 'redis'),

Now that we updated this default argument to redis the default setting will select the redis store even if the CACHE_STORE setting is not provided in the .env file.

At this point our default store setting selects the redis store that is using a redis driver connection named cache to connect to the Redis server when we use Laravels API.

The cache connection is configured in the redis driver settings in the config/database.php file which was configured in step 4.

How that all works will be described in the next to last section of this article.

Step 9 - Use the cache service

Startup the docker service

docker-compose up -d

You should now be able to use caching with Redis in your Laravel application.

Start tinker:

php artisan tinker

Try the various caching methods of the the cache facade.

//use default cache store from config/cache.php
Cache::put('key', 'value');
$value = Cache::get('key');
$hasKey = Cache::has('key');
Cache::forget('key');

//explicitly use the 'redis' store from config/cache.php
Cache::store('redis')->put('key', 'value');
$value = Cache::store('file')->get('foo');
$hasKey = Cache::store('redis')->has('key');
Cache::store('redis')->forget('key');

When done you can shutdown the docker service

docker-compose down

Creating and using additional non default redis cache stores

The cache store configured by the default setting is used by the Laravel cache helper, Cache facade, CacheManager and Cache class methods by default without requiring and explicit cache store name to be passed in to the connection.

However we can create additional redis stores and explicitly pass them in to the cache methods to use different stores.

We can create additional redis stores in the stores array in config/cache.php file and configure them in the same way as we configured the default redis cache store.

We can then use these stores by passing them in explicitly by name to the Laravel cache helper, cache facade, CacheManager and Cache class methods.

Here is an example of configuring additional cache stores and cache connections:

In config/database.php add a cache2 connection with a c2 key prefix.

Both the original cache connection and the new cache2 connection are shown below:

'redis' => [

        'cache' => [
            'url' => env('REDIS_URL'),
            'host' => env('REDIS_HOST', '127.0.0.1'),
            'password' => env('REDIS_PASSWORD', null),
            'port' => env('REDIS_PORT', '6379'),
            //database set to 0 since only database 0 is supported in redis cluster
            'database' => '0',
            //redis key prefix for this connection
            'prefix' => 'c:',
        ],

        'cache2' => [
            'url' => env('REDIS_URL'),
            'host' => env('REDIS_HOST', '127.0.0.1'),
            'password' => env('REDIS_PASSWORD', null),
            'port' => env('REDIS_PORT', '6379'),
            //database set to 0 since only database 0 is supported in redis cluster
            'database' => '0',
            //redis key prefix for this connection
            'prefix' => 'c2:',
        ],

    ],

Note that both cache connections use the same Redis server host settings. We could for scalability add a different REDIS_HOST_2 env setting to use a completely separate Redis server in production.

Next in config/cache.php add a redis2 store that uses the new cache2 connection.

Both the default redis store and the new cache2 store are shown below:

    'default' => env('CACHE_STORE', 'redis'),
    'stores' => [
        'redis' => [
                'driver' => 'redis', //the actual cache driver for the 'redis' store
                'connection' => 'cache',//the redis connection setting as specified in the config/database.php file
                'lock_connection' => 'default',
            ],
        //additional redis store that we can explicitly pass for example to the laravel cache facade
         'redis2' => [
                'driver' => 'redis', //the actual cache driver for the 'redis' store
                'connection' => 'cache2',//the new redis connection setting as specified in the config/database.php file
                'lock_connection' => 'default',
            ],
    ]

With this setup we could explicitly pass the string redis2 to the cache helper or facade methods to use the redis store that uses the cache2 connection to access the Redis server.

Looking at the configured settings in context

The 'default' => env('CACHE_STORE', 'redis') setting was configured to select the redis store setting, in the stores array.

Within the redis store setting there is a driver and connection setting as shown below:

    'stores' => [
        //the 'redis' cache store that is selected by the setting above when CACHE_STORE=redis in .env file
        'redis' => [
                'driver' => 'redis', //the actual cache driver for the 'redis' store
                'connection' => 'cache',//the redis connection setting as specified in the config/database.php file
                'lock_connection' => 'default',
            ],
    ]

The driver setting refers to the redis driver section in the config/database.php file.

The connection setting refers to the cache connection within the redis driver section in the config/database.php file.

For reference, the redis driver setting at the root settings level in config/database.php snippet along with its cache connection setting is shown below:

'redis' => [
        'cache' => [
            'url' => env('REDIS_URL'),
            'host' => env('REDIS_HOST', '127.0.0.1'),
            'password' => env('REDIS_PASSWORD', null),
            'port' => env('REDIS_PORT', '6379'),
            //database set to 0 since only database 0 is supported in redis cluster
            'database' => `0`,
            //instead add prefix setting to distinguish between connections
            //prefix not required if using one redis server/cluster host per connection
            'prefix' => 'c:'
        ],
    ],

Now from within your Laravel application, the redis store we configured in configs/cache.php is used by the Laravel Cache:: facade, cache() helper or their underlying CacheManager and Cache classes by default without requiring the user to pass in a explicit cache store.

This is because the underlying CacheManager and Cache classes by default use the default store (from the config/cache.php file) which is the redis store (from the config/cache.php file) which is configured to use the cache redis driver connection (from config/database.php).

Internally the underlying CacheManager and Cache classes delegate the RedisManager and Redis classes to connect to Redis server. They pass the cache connection to the delegated Redis classes to override the default connection (from config/database.php) that is used by default to connect to the Redis server by the Redis classes.

Key takeaways

The way the caches connect to your application in Laravel are through cache stores specified in the config/cache.php file.

Each cache store has an underlying driver.

If the driver for a cache store is configured as a redis driver then the cache store will have an underlying connection setting that refers to one of the available connections in the redis driver setting array within the config/database.php file.

The redis connections in the config/database.php file specify the connection parameters of the Redis server that the Laravel cache API methods will connect to.

This default connection can be overridden by passing in the name of another cache store, that is configured with a different connection name, to the Laravel cache API.