feat: use new X-RateLimit-Reset-After header with millisecond X-RateL…

…imit-Precision

lib/rest/functions.ex

@@ -189,8 +189,6 @@ defmodule Crux.Rest.Functions do
       message,
       &Endpoints.message_reactions(&1, &2, emoji, "@me")
     )
-    # https://github.com/discordapp/discord-api-docs/issues/182
-    |> Request.set_rate_limit_reset(250)
   end
 
   @impl true

lib/rest/handler/global.ex

@@ -13,28 +13,6 @@ defmodule Crux.Rest.Handler.Global do
     GenServer.start_link(__MODULE__, nil, name: name)
   end
 
-  @doc """
-    Fetches the average out of the last ten offsets to discord servers in milliseconds.
-  """
-  @spec fetch_offset(name :: atom()) :: integer()
-  def fetch_offset(name) do
-    name
-    |> Module.concat(Global)
-    |> GenServer.call(:offset)
-  end
-
-  @doc """
-    Adds an offset to the list of offsets.
-  """
-  @spec add_offset(name :: atom(), offset :: integer()) :: :ok
-  def add_offset(_name, nil), do: :ok
-
-  def add_offset(name, offset) do
-    name
-    |> Module.concat(Global)
-    |> GenServer.call({:offset, offset})
-  end
-
   @doc """
     Fetches how long to wait until the global rate limit is over.
     Is not positive when not rate limited.
@@ -66,24 +44,6 @@ defmodule Crux.Rest.Handler.Global do
 
   @doc false
   @impl true
-  def handle_call(:offset, _from, {offsets, _reset} = state) when length(offsets) <= 0 do
-    {:reply, 0, state}
-  end
-
-  def handle_call(:offset, _from, {offsets, _reset} = state) do
-    offset =
-      offsets
-      |> Enum.sum()
-      |> div(length(offsets))
-
-    {:reply, offset, state}
-  end
-
-  def handle_call({:offset, offset}, _from, {offsets, reset}) do
-    offsets = [offset | Enum.slice(offsets, 0..9)]
-
-    {:reply, :ok, {offsets, reset}}
-  end
 
   def handle_call(:retry, _from, {_offsets, reset} = state) do
     {:reply, reset - :os.system_time(:millisecond), state}

lib/rest/handler/handler.ex

@@ -132,14 +132,6 @@ defmodule Crux.Rest.Handler do
       |> handle_headers(res)
       |> handle_response(res)
 
-    # https://github.com/discordapp/discord-api-docs/issues/182
-    state =
-      if request.rate_limit_reset do
-        %{state | reset: request.rate_limit_reset + :os.system_time(:millisecond)}
-      else
-        state
-      end
-
     if is_number(wait) do
       Logger.debug("[Crux][Rest][Handler][#{route}]: Waiting #{wait}ms")
       :timer.sleep(wait)
@@ -166,29 +158,20 @@ defmodule Crux.Rest.Handler do
 
   # Apply rate limit and date header
   defp handle_headers(
-         %Handler{name: name} = state,
+         %Handler{} = state,
          {:ok, %HTTPoison.Response{headers: headers}}
        ) do
-    date =
-      headers
-      |> List.keyfind("Date", 0)
-      |> parse_header()
-
-    Global.add_offset(name, date)
-
     remaining =
       headers
       |> List.keyfind("X-RateLimit-Remaining", 0)
       |> parse_header()
 
     reset =
       headers
-      |> List.keyfind("X-RateLimit-Reset", 0)
+      |> List.keyfind("X-RateLimit-Reset-After", 0)
       |> parse_header()
 
     if remaining && reset do
-      reset = reset * 1000 - Global.fetch_offset(name)
-
       %{state | remaining: remaining, reset: reset}
     else
       state
@@ -249,17 +232,13 @@ defmodule Crux.Rest.Handler do
   defp parse_header(nil), do: nil
   defp parse_header({"X-RateLimit-Global", _value}), do: true
 
-  defp parse_header({"Date", value}) do
-    case Timex.parse(value, "{WDshort}, {D} {Mshort} {YYYY} {h24}:{m}:{s} {Zabbr}") do
-      {:ok, date_time} ->
-        DateTime.to_unix(date_time, :millisecond) - :os.system_time(:millisecond)
+  defp parse_header({"X-RateLimit-Remaining", value}), do: String.to_integer(value)
 
-      {:error, _} ->
-        nil
-    end
-  end
+  defp parse_header({"X-RateLimit-Reset-After", value}) do
 
-  defp parse_header({_name, value}), do: String.to_integer(value)
+    {value, ""} = Float.parse(value)
+    trunc(value * 1000) + :os.system_time(:millisecond)
+  end
 
   defp wait(timeout, route) when timeout > 0 do
     Logger.debug("[Crux][Rest][Handler][#{route}]: Rate limited, waiting #{timeout}ms")

lib/rest/http.ex

@@ -22,6 +22,7 @@ defmodule Crux.Rest.HTTP do
   def process_request_headers(headers) do
     headers
     |> Keyword.put_new(:"content-type", "application/json")
+    |> Keyword.put_new(:"X-RateLimit-Precision", "millisecond")
     |> Keyword.put_new(:"user-agent", @user_agent)
   end
 

lib/rest/request.ex

@@ -15,7 +15,6 @@ defmodule Crux.Rest.Request do
     :route,
     :path,
     :transform,
-    :rate_limit_reset,
     :params,
     data: "",
     headers: []
@@ -91,14 +90,6 @@ defmodule Crux.Rest.Request do
     %{t | headers: [{"authorization", "Bot " <> token} | headers]}
   end
 
-  @doc false
-  # https://github.com/discordapp/discord-api-docs/issues/182
-  Version.since("0.2.0")
-  @spec set_rate_limit_reset(t(), reset :: non_neg_integer() | nil) :: t()
-  def set_rate_limit_reset(%__MODULE__{} = t, reset) do
-    %{t | rate_limit_reset: reset}
-  end
-
   ### End Create / Set
 
   ### Work