README

Flysystem uses adapters as an abstraction for storage implementations. This library contains a set of meta-adapters that take 1 or more adapters as their input and expose them as a normal adapter.

OverlayAdapter

While Flysystem has a mount manager, this requires explicit knowledge of the mounts on the consumer side. For separating concerns this is not ideal. Imagine just exposing an adapter to your code (via a FileSystem) and having the magic of different backends be handled on the configuration side.

The OverlayAdapter for example could allow you to have any Flysystem compatible file browser and use it to browse a virtual filesystem that consists of both real files on S3 storage, real files on local storage and virtual directories pulled from your database.

DirectoryViaPlaceholderFileAdapter

Some storages don't support directories. Many of the S3 based stores don't have directories as a concept. This adapter adds supports for directories by using a placeholder file. The idea being that a file in a path defines a directory.

MetadataCachingAdapter

Some APIs have 1 API call for getting all metadata. This adapter caches that so that you don't see multiple API requests for calls to lastModified and size on the same file. Use this only for adapters that retrieve all metadata for calls to lastModified and mimeType etc.

StripPrefixAdapter

Removes a prefix from all paths passed to the adapter. Used in combination with the OverlayAdapter to mount one adapter inside a path of another.

AddPrefixAdapter

Adds a prefix to all paths passed to the adapter. Used in combination with the OverlayAdapter to mount one adapter inside a path of another.

VirtualDirectoryListAdapter

Sometimes you want to have a directory available for each entity in your system, imagine a folder for each user. If there are many users getting the list from the storage API might be slow, but you already have the list in your local database. By using this adapter you can specify a list of directories in a specific path on the underlying adapter.

OverlayAdapter

Mount one adapter onto another using a path prefix.

EventedAdapter

This adapter uses a PSR-14 EventDispatcher to dispatch events before and after operations that modify storage. Initial use case for them is to notify CDNs to update their cache.

MoveOverwriteAdapter

This adapter wraps any other adapter and will try to force an overwrite if moving a file fails. This means upon failure it will check if the destination file exists and if so remove it and retry the move command.