Using Redis with PHP
In order to use Redis with PHP you will need a PHP Redis client. In following sections, we will demonstrate the use of Predis, a flexible and feature-complete Redis client library for PHP >= 5.3. Additional PHP clients for Redis can be found under the PHP section of the Redis Clients page.
Predis' installation instructions are given in the "How to Use Predis" section of its README file. The recommended method for installing Predis is to use Composer and install it from Packagist or the dedicated PEAR channel.
You can also download the latest Predis release from the GitHub repository.
Opening a Connection to Redis Using Predis
The following code creates a connection to Redis using Predis:
<?php require "predis/autoload.php"; Predis\Autoloader::register(); $redis = new Predis\Client(array( "scheme" => "tcp", "host" => "hostname", "port" => port, "password” => “password")); echo "Connected to Redis"; ?>
Unless you've installed Predis with Composer, you'll need to include the 2nd and 3rd lines of code to load and register the Predis client library. To adapt this example to your code, make sure that you replace the following values with those of your database:
- In line 8,
hostshould refer to your database's hostname or IP address
- In line 9,
portshould be your database's port
- In line 10,
passwordshould be your database's password
Persistent Connections with Predis
Predis supports the use of persistent connections, which are recommended practice to minimizeconnection management overhead. To enable persistent connections, use the
persistent connection attribute as shown in the following snippet:
$redis = new Predis\Client(array( "scheme" => "tcp", "host" => "hostname", "port" => port, "password” => "password", "persistent" => "1"));
Using SSL and Predis
Reading and Writing Data with Predis
Once connected to Redis, you can start reading and writing data. The following code snippet writes the value
bar to the Redis key
foo, reads it back, and prints it:
// open a connection to Redis ... $redis->set("foo", "bar"); $value = $redis->get("foo"); var_dump($value);
The output of the above code should be:
$ php predis_example.php Connected to Redis string(3) "bar"