Merge branch 'release/2.2.0' into 'stable'v2.2.0

Release/2.2.0

See merge request pleroma/secteam/pleroma!19

1 files changed, 185 insertions, 0 deletions

diff --git a/lib/pleroma/web/fed_sockets/fed_registry.ex b/lib/pleroma/web/fed_sockets/fed_registry.ex
new file mode 100644
index 000000000..e00ea69c0
--- /dev/null
+++ b/lib/pleroma/web/fed_sockets/fed_registry.ex
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+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2020 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.Web.FedSockets.FedRegistry do
+  @moduledoc """
+  The FedRegistry stores the active FedSockets for quick retrieval.
+
+  The storage and retrieval portion of the FedRegistry is done in process through
+  elixir's `Registry` module for speed and its ability to monitor for terminated processes.
+
+  Dropped connections will be caught by `Registry` and deleted. Since the next
+  message will initiate a new connection there is no reason to try and reconnect at that point.
+
+  Normally outside modules should have no need to call or use the FedRegistry themselves.
+  """
+
+  alias Pleroma.Web.FedSockets.FedSocket
+  alias Pleroma.Web.FedSockets.SocketInfo
+
+  require Logger
+
+  @default_rejection_duration 15 * 60 * 1000
+  @rejections :fed_socket_rejections
+
+  @doc """
+  Retrieves a FedSocket from the Registry given it's origin.
+
+  The origin is expected to be a string identifying the endpoint "example.com" or "example2.com:8080"
+
+  Will return:
+    * {:ok, fed_socket} for working FedSockets
+    * {:error, :rejected} for origins that have been tried and refused within the rejection duration interval
+    * {:error, some_reason} usually :missing for unknown origins
+  """
+  def get_fed_socket(origin) do
+    case get_registry_data(origin) do
+      {:error, reason} ->
+        {:error, reason}
+
+      {:ok, %{state: :connected} = socket_info} ->
+        {:ok, socket_info}
+    end
+  end
+
+  @doc """
+  Adds a connected FedSocket to the Registry.
+
+  Always returns {:ok, fed_socket}
+  """
+  def add_fed_socket(origin, pid \\ nil) do
+    origin
+    |> SocketInfo.build(pid)
+    |> SocketInfo.connect()
+    |> add_socket_info
+  end
+
+  defp add_socket_info(%{origin: origin, state: :connected} = socket_info) do
+    case Registry.register(FedSockets.Registry, origin, socket_info) do
+      {:ok, _owner} ->
+        clear_prior_rejection(origin)
+        Logger.debug("fedsocket added: #{inspect(origin)}")
+
+        {:ok, socket_info}
+
+      {:error, {:already_registered, _pid}} ->
+        FedSocket.close(socket_info)
+        existing_socket_info = Registry.lookup(FedSockets.Registry, origin)
+
+        {:ok, existing_socket_info}
+
+      _ ->
+        {:error, :error_adding_socket}
+    end
+  end
+
+  @doc """
+  Mark this origin as having rejected a connection attempt.
+  This will keep it from getting additional connection attempts
+  for a period of time specified in the config.
+
+  Always returns {:ok, new_reg_data}
+  """
+  def set_host_rejected(uri) do
+    new_reg_data =
+      uri
+      |> SocketInfo.origin()
+      |> get_or_create_registry_data()
+      |> set_to_rejected()
+      |> save_registry_data()
+
+    {:ok, new_reg_data}
+  end
+
+  @doc """
+  Retrieves the FedRegistryData from the Registry given it's origin.
+
+  The origin is expected to be a string identifying the endpoint "example.com" or "example2.com:8080"
+
+  Will return:
+    * {:ok, fed_registry_data} for known origins
+    * {:error, :missing} for uniknown origins
+    * {:error, :cache_error} indicating some low level runtime issues
+  """
+  def get_registry_data(origin) do
+    case Registry.lookup(FedSockets.Registry, origin) do
+      [] ->
+        if is_rejected?(origin) do
+          Logger.debug("previously rejected fedsocket requested")
+          {:error, :rejected}
+        else
+          {:error, :missing}
+        end
+
+      [{_pid, %{state: :connected} = socket_info}] ->
+        {:ok, socket_info}
+
+      _ ->
+        {:error, :cache_error}
+    end
+  end
+
+  @doc """
+  Retrieves a map of all sockets from the Registry. The keys are the origins and the values are the corresponding SocketInfo
+  """
+  def list_all do
+    (list_all_connected() ++ list_all_rejected())
+    |> Enum.into(%{})
+  end
+
+  defp list_all_connected do
+    FedSockets.Registry
+    |> Registry.select([{{:"$1", :_, :"$3"}, [], [{{:"$1", :"$3"}}]}])
+  end
+
+  defp list_all_rejected do
+    {:ok, keys} = Cachex.keys(@rejections)
+
+    {:ok, registry_data} =
+      Cachex.execute(@rejections, fn worker ->
+        Enum.map(keys, fn k -> {k, Cachex.get!(worker, k)} end)
+      end)
+
+    registry_data
+  end
+
+  defp clear_prior_rejection(origin),
+    do: Cachex.del(@rejections, origin)
+
+  defp is_rejected?(origin) do
+    case Cachex.get(@rejections, origin) do
+      {:ok, nil} ->
+        false
+
+      {:ok, _} ->
+        true
+    end
+  end
+
+  defp get_or_create_registry_data(origin) do
+    case get_registry_data(origin) do
+      {:error, :missing} ->
+        %SocketInfo{origin: origin}
+
+      {:ok, socket_info} ->
+        socket_info
+    end
+  end
+
+  defp save_registry_data(%SocketInfo{origin: origin, state: :connected} = socket_info) do
+    {:ok, true} = Registry.update_value(FedSockets.Registry, origin, fn _ -> socket_info end)
+    socket_info
+  end
+
+  defp save_registry_data(%SocketInfo{origin: origin, state: :rejected} = socket_info) do
+    rejection_expiration =
+      Pleroma.Config.get([:fed_sockets, :rejection_duration], @default_rejection_duration)
+
+    {:ok, true} = Cachex.put(@rejections, origin, socket_info, ttl: rejection_expiration)
+    socket_info
+  end
+
+  defp set_to_rejected(%SocketInfo{} = socket_info),
+    do: %SocketInfo{socket_info | state: :rejected}
+end