postland/lib/activity_pub.ex

defmodule ActivityPub do
  def get(url, actor_url, private_key) do
    headers = ActivityPub.Headers.signing_headers("GET", url, "", actor_url, private_key)

    Req.new(url: url)
    |> Req.Request.put_header("accept", "application/activity+json")
    |> Req.Request.put_headers(headers)
    |> Req.get()
    |> case do
      {:ok, response} ->
        {:ok, response.body}

      other ->
        other
    end
  end

  def fetch_actor(actor_id) do
    request =
      Req.new(url: actor_id)
      |> Req.Request.put_header("accept", "application/json")

    case Req.get(request) do
      {:ok, result} ->
        {:ok, result.body}

      error ->
        error
    end
  end
end