exfile v0.3.0 Exfile.Backend behaviour

Represents a backend that stores files.

Summary

Functions

Deletes a file from the given backend by the file ID

A convenience function to call backend.backend_mod.exists?(backend, file_id)

Get the Exfile.File struct representing a file on the given backend

Opens a file on the given backend, applying postprocessors if configured

A convenience function to call backend.backend_mod.path(backend, file_id)

A convenience function to call backend.backend_mod.size(backend, file_id)

Uploads a file to the given backend, applying preprocessors if configured

Callbacks

Delete a file from the backend, identified by file_id

Construct an Exfile.File struct representing the given file_id

Open a file from the backend. This function should download the file either to a temporary file or to memory in the Exfile.LocalFile struct

Get the size of a file from the backend

upload/2 must handle at least two cases of uploadable

Types

backend :: t
t :: %Exfile.Backend{backend_mod: atom, backend_name: String.t, directory: String.t, hasher: atom, max_size: integer, meta: map, postprocessors: [Exfile.ProcessorChain.definition, ...], preprocessors: [Exfile.ProcessorChain.definition, ...]}

Functions

delete(backend, file_id)

Specs

delete(backend, file_id) ::
  :ok |
  {:error, :file.posix}

Deletes a file from the given backend by the file ID.

exists?(backend, file_id)

Specs

exists?(backend, file_id) :: boolean

A convenience function to call backend.backend_mod.exists?(backend, file_id)

get(backend, file_id)

Specs

Get the Exfile.File struct representing a file on the given backend.

This function does not open the file or download it. Use open/2 or Exfile.File.open/1 to open the file.

open(backend, file_id)

Specs

open(backend, file_id) ::
  {:ok, Exfile.LocalFile.t} |
  {:error, :file.posix}

Opens a file on the given backend, applying postprocessors if configured.

path(backend, file_id)

Specs

path(backend, file_id) :: Path.t

A convenience function to call backend.backend_mod.path(backend, file_id)

size(backend, file_id)

Specs

size(backend, file_id) ::
  {:ok, pos_integer} |
  {:error, :file.posix}

A convenience function to call backend.backend_mod.size(backend, file_id)

upload(backend, uploadable)

Specs

upload(backend, uploadable) ::
  {:ok, Exfile.File.t} |
  {:error, atom}

Uploads a file to the given backend, applying preprocessors if configured.

Callbacks

delete(backend, file_id)

Specs

delete(backend, file_id) ::
  :ok |
  {:error, :file.posix}

Delete a file from the backend, identified by file_id.

exists?(backend, file_id)

Specs

exists?(backend, file_id) :: boolean
get(backend, file_id)

Specs

Construct an Exfile.File struct representing the given file_id.

init(list)

Specs

init([{:name, String.t}]) :: backend | {:error, atom}
open(backend, file_id)

Specs

open(backend, file_id) ::
  {:ok, Exfile.LocalFile.t} |
  {:error, :file.posix}

Open a file from the backend. This function should download the file either to a temporary file or to memory in the Exfile.LocalFile struct.

path(backend, file_id)

Specs

path(backend, file_id) :: Path.t
size(backend, file_id)

Specs

size(backend, file_id) ::
  {:ok, pos_integer} |
  {:error, :file.posix}

Get the size of a file from the backend

upload(backend, uploadable)

Specs

upload(backend, uploadable) ::
  {:ok, Exfile.File.t} |
  {:error, atom}

upload/2 must handle at least two cases of uploadable:

  1. an %Exfile.File{}
  2. an %Exfile.LocalFile{}

You may elect to implement a third case that handles uploading between identical backends, if there is a more efficient way to implement it. See Exfile.Backend.FileSystem.upload/2 for an example.