FileStore

FileStore allows you to read, write, upload, download, and interact with files, regardless of where they are stored.

It includes adapters for the following storage backends:

• Disk
• S3
• Memory
• Null

View the documentation

Installation

The package can be installed by adding file_store to your list of dependencies in mix.exs:

def deps do
  [{:file_store, "~> 0.3"}]
end

Usage

Configure a new store:

store = FileStore.Adapters.Disk.new(
  storage_path: "/path/to/store/files",
  base_url: "http://example.com/files/"
)

Now, you can manipulate files in your store:

iex> FileStore.upload(store, "hello.txt", "world.txt")
:ok

iex> FileStore.read(store, "world.txt")
{:ok, "hello world"}

iex> FileStore.stat(store, "world.txt")
{:ok,
 %FileStore.Stat{
   etag: "5eb63bbbe01eeed093cb22bb8f5acdc3",
   key: "hello.txt",
   size: 11,
   type: "application/octet-stream"
 }}

iex> FileStore.get_public_url(store, "world.txt")
"http://localhost:4000/world.txt"

Click here to see all available operations.

Middleware

Logger

To enable logging, just wrap your store with the logging middleware:

iex> store
...> |> FileStore.Middleware.Logger.new()
...> |> FileStore.read("test.txt")
# 02:37:30.724 [debug] READ OK key="test.txt"
{:ok, "hello"}

Errors

The errors middleware will wrap error values:

iex> store
...> |> FileStore.Middleware.Errors.new()
...> |> FileStore.read("bizcorp.jpg")
{:error, %FileStore.Error{...}}

One of the following structs will be returned:

• FileStore.Error
• FileStore.UploadError
• FileStore.DownloadError
• FileStore.CopyError
• FileStore.RenameError

Because the error implements the Exception behaviour, you can raise it.

Prefix

The prefix middleware allows you to prepend a prefix to all operations.

iex> store
...> |> FileStore.Middleware.Prefix.new(prefix: "company/logos")
...> |> FileStore.read("bizcorp.jpg")

In the example above, bizcorp.jpg was translated to companies/logos/bizcorp.jpg.

Creating a store

You can also create a dedicated store in your application.

defmodule MyApp.Storage do
  use FileStore.Config, otp_app: :my_app
end

You'll need to provide configuration for this module:

config :my_app, MyApp.Storage,
  adapter: FileStore.Adapters.Null,
  middleware: [FileStore.Middleware.Errors]

Now, you can interact with your store more conveniently:

iex> MyApp.Storage.write("foo", "hello world")
:ok

iex> MyApp.Storage.read("foo")
{:ok, "hello world"}

Contributing

In order to test the S3 adapter, we run Minio locally in a Docker container. To start the Minio service, run the following script:

$ bin/start

To run the test suite, run:

$ bin/test