> For the complete documentation index, see [llms.txt](https://xoops.gitbook.io/xmf-cookbook/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://xoops.gitbook.io/xmf-cookbook/reference/jwt/keyfactory.md).

# KeyFactory

The `Xmf\Jwt\KeyFactory` class is a factory used to build key objects for use in a [JsonWebToken](/xmf-cookbook/reference/jwt/jsonwebtoken.md) object.

## KeyFactory:build(*$keyName*, *$storage* = null)

Returns a `Xmf\Key\Basic` key object for JWT use based on default choices. If the key, specified by name in *$keyName*, has not been established, it will be created.

The *$keyName* key name is a string, the symbolic name of the key to use. The *$keyName* uniquely identifies a key in a key store, as defined by the interface `Xmf\Key\StorageInterface`. The key name should relate to a specific application action, or a closely related set of actions.

If specified, *$storage* should be an instance of `Xmf\Key\StorageInterface`. If *null* a default [FileStorage](/xmf-cookbook/reference/key/filestorage.md) instance will be used.


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