defmodule ExOvh.Transformation.Auth do
@moduledoc :false
@default_headers [{"Content-Type", "application/json; charset=utf-8"}]
# Public
@spec apply(HTTPipe.Conn.t, atom) :: HTTPipe.Conn.t
def apply(%HTTPipe.Conn{request: %HTTPipe.Request{method: method, headers: headers, url: url}} = conn, client) do
trans = Map.get(conn, :completed_transformations, [])
unless (Enum.member?(trans, :url)), do: raise ":url must be added to the transformations before applying the :auth step"
ovh_config = client.ovh_config()
headers = Map.merge(headers, headers([ovh_config[:application_secret], ovh_config[:application_key], ovh_config[:consumer_key], Atom.to_string(method), url, ""], client))
request = Map.put(conn.request, :headers, headers)
Map.put(conn, :request, request)
|> Map.put(:completed_transformations, trans ++ [:auth])
end
# Private
defp headers([app_secret, app_key, consumer_key, method, url, body] = _opts, client) do
time = :os.system_time(:seconds) + ExOvh.Config.get_diff(client)
headers = [
{"X-Ovh-Application", app_key},
{"X-Ovh-Consumer", consumer_key},
{"X-Ovh-Timestamp", time},
{"X-Ovh-Signature", sign_request([app_secret, consumer_key, String.upcase(method), url, body, time])}
]
|> Enum.into(%{})
Map.merge(Enum.into(@default_headers, %{}), headers)
end
defp sign_request([_app_secret, _consumer_key, _method, _uri, _body, _time] = opts) do
pre_hash = Enum.join(opts, "+")
post_hash = :crypto.hash(:sha, pre_hash) |> Base.encode16(case: :lower)
"$1$" <> post_hash
end
end
