Stash makes it easy to speed up your code by caching the results of expensive functions or code. Certain actions, like database queries or calls to external APIs, take a lot of time to run but tend to have the same results over short periods of time. This makes it much more efficient to store the results and call them back up later.

Installing Stash can be done through a variety of methods, although Composer is recommended.

Until Stash reaches a stable API with version 1.0 it is recommended that you review changes before Minor updates, although bug fixes will always be backwards compatible.

"require": {
  "tedivm/stash": "0.17.*"
}

or by using the composer require command:

composer require tedivm/stash

Releases of Stash are available on Github.

Although this README contains some useful data there is a lot more information at the main site, stashphp.com.

Stash has three main components: a Pool class that represents a specific grouping of cached objects, an Item class that provides access to individual objects, and a series of Driver classes that allow Stash to interact with caching systems.

Each Driver is initialized and then passed into a Pool, at which point the developer can simply forget about it. Developers also have the option of using multiple Drivers together by joining them with the Composite Driver.

The Pool class allows developers to perform a number of tasks. There are a few maintenance related tasks, such as running a "Purge" to allow backend systems to perform maintenance tasks or set new logging or driver classes. The Pool also can be used to create Item objects, singly or in groups.

Each Item represents a single object inside the cache. It has a unique Key, meaning that any two Items created from the same Pool will contain the same Value. An Item can set, get and remove a value from a caching system.

A Key is a string that represents an Item in a caching system. At its simplest, a key is an alphanumeric string and has a one to one relationship with a value in the cache.

Stash provides a feature known as "stacks" that allows developers to group related Items together so they can be erased as a group. This is done by giving Items a nested structure, similar to folders on a computer. Just like with folders, this is represented by adding slashes to the name representing the file or cached object.

For example, a Key like "/models/users/34/profile" can allow developers to clear the data for specific users using that user's id, or clear the data for all users or even all models. It can also allow that developer to break up data into specific pieces to only load what is needed.

The provided Session class takes a Pool in its constructor and can then be registered as a Session Handler using the built-in PHP methods, the Session::registerHandler static function, or by using any framework that uses the SessionHandlerInterface interface.

Stash currently supports the following backends:

• FileSystem
• Sqlite
• APC
• Memcached
• Redis
• Ephemeral (runtime only)

Stash also supports a specialized "Composite" Driver which can contain any number of the above drivers. This allows developers to created multi-tiered drivers that use a variety of back ends.

The Stash Bundle makes using Stash inside of Symfony projects significantly easier. This bundle exposes Stash as a Service for developers to use, and allows Symfony to use Stash as a session handler.

Stash is licensed under the BSD License. See the LICENSE file for details.

This project utilizes the Tidelift Security Reporting System for security and vulnerability reporting.

Issues can be opened directly in Github for issues that aren't related to security.

Professionally supported Stash is now available with Tidelift.