Down is a utility tool for streaming, flexible and safe downloading of remote files.

Down is a thin wrapper around different HTTP backends focus on efficient and safe downloads. It also allows you to change backend without any code modification.

The API is very small, it only consist in three operationsÑ

• read/2 to download the content directly in memory.
• download/2 to download the content in a local file.
• stream/2 allows to have a a much more precise control of the download.

Shared options

All the Down operations accept the following options:

• :max_size - The maximum size in bytes of the download. If the content is larger than this limit the function will return {:error, :too_large}.
• :headers - A Keyword or a Map containing all request headers. The key and value are converted to strings.
• :method - HTTP method used by the request. Possible values: :get, :post, :delete, :put, :patch, :options, :head, :connect, :trace. Default :get.
• :body- HTTP body request in binary format. Default: nil.
• :backend - The backend to use during for the request. Possible values: :hackney, :httpc and :httpoison.
• :backend_opts - Additional options passed to the backend. Notice: Down uses some options to work with the backend. In case of conflict, Down options will be used.
• :total_timeout - Timeout time for the request. The clock starts ticking when the request is sent. Time is in milliseconds. Default is :infinity.
• :inactivity_timeout - If a persistent connection is idle longer than the :inactivity_timeout in milliseconds, the client closes the connection. The server can also have such a timeout but do not take that for granted. Default is 120000 (= 2 min). Only implemented for :ibrowse backend.
• :connect_timeout - The time in milliseconds to wait for the request to connect, :infinity will wait indefinitely (default: 15_000).