Behaviour for generating storage paths for media files, plus a set of delegating functions that route calls to the configured implementation.

Built-in generators

• PhxMediaLibrary.PathGenerator.Default — {type}/{id}/{uuid}/{filename} (the default)
• PhxMediaLibrary.PathGenerator.Flat — {uuid}/{filename}
• PhxMediaLibrary.PathGenerator.DateBased — {year}/{month}/{day}/{type}/{id}/{uuid}/{filename}

Configuring a custom generator

config :phx_media_library,
  path_generator: PhxMediaLibrary.PathGenerator.DateBased

Writing a custom generator

Implement the PhxMediaLibrary.PathGenerator behaviour and configure it:

defmodule MyApp.TenantPathGenerator do
  @behaviour PhxMediaLibrary.PathGenerator

  @impl true
  def relative_path(media, conversion) do
    relative_path(media, conversion, %{})
  end

  @impl true
  def relative_path(media, conversion, path_context) do
    tenant_id = Map.get(path_context, :tenant_id, "shared")
    base = Path.join([to_string(tenant_id), media.mediable_type, media.mediable_id, media.uuid])
    ext = Path.extname(media.file_name)
    name = Path.rootname(media.file_name)
    filename = if conversion, do: "#{name}_#{conversion}#{ext}", else: media.file_name
    Path.join(base, filename)
  end

  @impl true
  def for_new_media(attrs), do: for_new_media(attrs, %{})

  @impl true
  def for_new_media(attrs, path_context) do
    tenant_id = Map.get(path_context, :tenant_id, "shared")
    Path.join([to_string(tenant_id), attrs.mediable_type, attrs.mediable_id, attrs.uuid, attrs.file_name])
  end
end

Then configure:

config :phx_media_library,
  path_generator: MyApp.TenantPathGenerator

And pass context when generating paths:

PhxMediaLibrary.PathGenerator.relative_path(media, :thumb, %{tenant_id: "acme"})

The path_context escape hatch

The optional path_context map lets you thread arbitrary data — such as tenant_id, user_id, or space_id — into a custom path generator without coupling to custom_properties or the media schema itself.

The built-in generators ignore path_context; custom generators may use it however they like.

The 3-arity forms of relative_path/3 and for_new_media/2 are @optional_callbacks. If your generator does not implement them, calls that supply a path_context fall back gracefully to the 2-arity / 1-arity forms.