From cf96c4005743c61d44e17c9d37c6427eaf69c152 Mon Sep 17 00:00:00 2001
From: Ivan Tashkinov <ivantashkinov@gmail.com>
Date: Wed, 22 Jan 2020 21:10:17 +0300
Subject: [#1505] Added Mastodon-compatible `replies` collection to Note
 federated representation.

---
 lib/pleroma/activity.ex                        | 19 +++++++++++
 lib/pleroma/activity/queries.ex                | 18 ++++++++++-
 lib/pleroma/web/activity_pub/transmogrifier.ex | 44 ++++++++++++++++++++++++++
 3 files changed, 80 insertions(+), 1 deletion(-)

(limited to 'lib')

diff --git a/lib/pleroma/activity.ex b/lib/pleroma/activity.ex
index 896cbb3c5..b7be7a800 100644
--- a/lib/pleroma/activity.ex
+++ b/lib/pleroma/activity.ex
@@ -329,4 +329,23 @@ defmodule Pleroma.Activity do
       _ -> nil
     end
   end
+
+  def replies(activity, opts \\ []) do
+    object = Object.normalize(activity)
+
+    query =
+      Activity
+      |> Queries.by_type("Create")
+      |> Queries.by_object_in_reply_to_id(object.data["id"], skip_preloading: true)
+      |> order_by([activity], asc: activity.id)
+
+    if opts[:self_only] do
+      where(query, [a], a.actor == ^activity.actor)
+    else
+      query
+    end
+  end
+
+  def self_replies(activity, opts \\ []),
+    do: replies(activity, Keyword.put(opts, :self_only, true))
 end
diff --git a/lib/pleroma/activity/queries.ex b/lib/pleroma/activity/queries.ex
index 79f305201..c17affec9 100644
--- a/lib/pleroma/activity/queries.ex
+++ b/lib/pleroma/activity/queries.ex
@@ -7,7 +7,7 @@ defmodule Pleroma.Activity.Queries do
   Contains queries for Activity.
   """
 
-  import Ecto.Query, only: [from: 2]
+  import Ecto.Query, only: [from: 2, where: 3]
 
   @type query :: Ecto.Queryable.t() | Activity.t()
 
@@ -63,6 +63,22 @@ defmodule Pleroma.Activity.Queries do
     )
   end
 
+  @spec by_object_id(query, String.t()) :: query
+  def by_object_in_reply_to_id(query, in_reply_to_id, opts \\ []) do
+    query =
+      if opts[:skip_preloading] do
+        Activity.with_joined_object(query)
+      else
+        Activity.with_preloaded_object(query)
+      end
+
+    where(
+      query,
+      [activity, object: o],
+      fragment("(?)->>'inReplyTo' = ?", o.data, ^to_string(in_reply_to_id))
+    )
+  end
+
   @spec by_type(query, String.t()) :: query
   def by_type(query \\ Activity, activity_type) do
     from(
diff --git a/lib/pleroma/web/activity_pub/transmogrifier.ex b/lib/pleroma/web/activity_pub/transmogrifier.ex
index 2b8bfc3bd..9e712ab75 100644
--- a/lib/pleroma/web/activity_pub/transmogrifier.ex
+++ b/lib/pleroma/web/activity_pub/transmogrifier.ex
@@ -903,6 +903,49 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
 
   def set_reply_to_uri(obj), do: obj
 
+  @doc """
+  Serialized Mastodon-compatible `replies` collection containing _self-replies_.
+  Based on Mastodon's ActivityPub::NoteSerializer#replies.
+  """
+  def set_replies(obj) do
+    limit = Pleroma.Config.get([:mastodon_compatibility, :federated_note_replies_limit], 0)
+
+    replies_uris =
+      with true <- limit > 0 || nil,
+           %Activity{} = activity <- Activity.get_create_by_object_ap_id(obj["id"]) do
+        activity
+        |> Activity.self_replies()
+        |> select([a], fragment("?->>'id'", a.data))
+        |> limit(^limit)
+        |> Repo.all()
+      end
+
+    set_replies(obj, replies_uris || [])
+  end
+
+  defp set_replies(obj, replies_uris) when replies_uris in [nil, []] do
+    obj
+  end
+
+  defp set_replies(obj, replies_uris) do
+    # Note: stubs (Mastodon doesn't make separate requests via those URIs in FetchRepliesService)
+    masto_replies_uri = nil
+    masto_replies_next_page_uri = nil
+
+    replies_collection = %{
+      "type" => "Collection",
+      "id" => masto_replies_uri,
+      "first" => %{
+        "type" => "Collection",
+        "part_of" => masto_replies_uri,
+        "items" => replies_uris,
+        "next" => masto_replies_next_page_uri
+      }
+    }
+
+    Map.merge(obj, %{"replies" => replies_collection})
+  end
+
   # Prepares the object of an outgoing create activity.
   def prepare_object(object) do
     object
@@ -914,6 +957,7 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
     |> prepare_attachments
     |> set_conversation
     |> set_reply_to_uri
+    |> set_replies
     |> strip_internal_fields
     |> strip_internal_tags
     |> set_type
-- 
cgit v1.2.3


From 86e4d23acb640efea8cbc879ddbeadfa0e04f9c8 Mon Sep 17 00:00:00 2001
From: Ivan Tashkinov <ivantashkinov@gmail.com>
Date: Sat, 25 Jan 2020 10:47:30 +0300
Subject: [#1505] Background fetching of incoming activities' `replies`
 collections.

---
 lib/pleroma/web/activity_pub/transmogrifier.ex | 15 ++++++++++++++-
 lib/pleroma/workers/remote_fetcher_worker.ex   | 20 ++++++++++++++++++++
 2 files changed, 34 insertions(+), 1 deletion(-)
 create mode 100644 lib/pleroma/workers/remote_fetcher_worker.ex

(limited to 'lib')

diff --git a/lib/pleroma/web/activity_pub/transmogrifier.ex b/lib/pleroma/web/activity_pub/transmogrifier.ex
index 9e712ab75..d129334c2 100644
--- a/lib/pleroma/web/activity_pub/transmogrifier.ex
+++ b/lib/pleroma/web/activity_pub/transmogrifier.ex
@@ -424,7 +424,13 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
           ])
       }
 
-      ActivityPub.create(params)
+      with {:ok, created_activity} <- ActivityPub.create(params) do
+        for reply_id <- replies(object) do
+          Pleroma.Workers.RemoteFetcherWorker.enqueue("fetch_remote", %{"id" => reply_id})
+        end
+
+        {:ok, created_activity}
+      end
     else
       %Activity{} = activity -> {:ok, activity}
       _e -> :error
@@ -946,6 +952,13 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
     Map.merge(obj, %{"replies" => replies_collection})
   end
 
+  def replies(%{"replies" => replies = %{}}) do
+    replies = with %{} <- replies["first"], do: replies["first"], else: (_ -> replies)
+    replies["items"] || []
+  end
+
+  def replies(_), do: []
+
   # Prepares the object of an outgoing create activity.
   def prepare_object(object) do
     object
diff --git a/lib/pleroma/workers/remote_fetcher_worker.ex b/lib/pleroma/workers/remote_fetcher_worker.ex
new file mode 100644
index 000000000..60eafe2c1
--- /dev/null
+++ b/lib/pleroma/workers/remote_fetcher_worker.ex
@@ -0,0 +1,20 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2019 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.Workers.RemoteFetcherWorker do
+  alias Pleroma.Object.Fetcher
+
+  use Pleroma.Workers.WorkerHelper, queue: "remote_fetcher"
+
+  @impl Oban.Worker
+  def perform(
+        %{
+          "op" => "fetch_remote",
+          "id" => id
+        },
+        _job
+      ) do
+    Fetcher.fetch_object_from_id!(id)
+  end
+end
-- 
cgit v1.2.3


From d458f4fdcafe847a7db8b1c663cfd945019816b7 Mon Sep 17 00:00:00 2001
From: Ivan Tashkinov <ivantashkinov@gmail.com>
Date: Sat, 8 Feb 2020 19:58:02 +0300
Subject: [#1505] Added tests, changelog entry, tweaked config settings related
 to replies output on outgoing federation.

---
 lib/pleroma/web/activity_pub/transmogrifier.ex | 10 ++++++++--
 lib/pleroma/workers/remote_fetcher_worker.ex   |  2 +-
 2 files changed, 9 insertions(+), 3 deletions(-)

(limited to 'lib')

diff --git a/lib/pleroma/web/activity_pub/transmogrifier.ex b/lib/pleroma/web/activity_pub/transmogrifier.ex
index d129334c2..623236720 100644
--- a/lib/pleroma/web/activity_pub/transmogrifier.ex
+++ b/lib/pleroma/web/activity_pub/transmogrifier.ex
@@ -914,7 +914,7 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
   Based on Mastodon's ActivityPub::NoteSerializer#replies.
   """
   def set_replies(obj) do
-    limit = Pleroma.Config.get([:mastodon_compatibility, :federated_note_replies_limit], 0)
+    limit = Pleroma.Config.get([:activitypub, :note_replies_output_limit], 0)
 
     replies_uris =
       with true <- limit > 0 || nil,
@@ -953,7 +953,13 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
   end
 
   def replies(%{"replies" => replies = %{}}) do
-    replies = with %{} <- replies["first"], do: replies["first"], else: (_ -> replies)
+    replies =
+      if is_map(replies["first"]) do
+        replies["first"]
+      else
+        replies
+      end
+
     replies["items"] || []
   end
 
diff --git a/lib/pleroma/workers/remote_fetcher_worker.ex b/lib/pleroma/workers/remote_fetcher_worker.ex
index 60eafe2c1..52db6059b 100644
--- a/lib/pleroma/workers/remote_fetcher_worker.ex
+++ b/lib/pleroma/workers/remote_fetcher_worker.ex
@@ -15,6 +15,6 @@ defmodule Pleroma.Workers.RemoteFetcherWorker do
         },
         _job
       ) do
-    Fetcher.fetch_object_from_id!(id)
+    {:ok, _object} = Fetcher.fetch_object_from_id(id)
   end
 end
-- 
cgit v1.2.3


From 7c3991f59eccc47551257dfe41817e71d0eb6717 Mon Sep 17 00:00:00 2001
From: Ivan Tashkinov <ivantashkinov@gmail.com>
Date: Sun, 9 Feb 2020 10:17:21 +0300
Subject: [#1505] Fixed `replies` serialization (included objects' ids instead
 of activities' ids).

---
 lib/pleroma/activity.ex                        | 19 -------------------
 lib/pleroma/object.ex                          | 22 ++++++++++++++++++++++
 lib/pleroma/web/activity_pub/transmogrifier.ex | 16 ++++++++--------
 3 files changed, 30 insertions(+), 27 deletions(-)

(limited to 'lib')

diff --git a/lib/pleroma/activity.ex b/lib/pleroma/activity.ex
index 10b6d7ebd..72e2256ea 100644
--- a/lib/pleroma/activity.ex
+++ b/lib/pleroma/activity.ex
@@ -330,23 +330,4 @@ defmodule Pleroma.Activity do
       _ -> nil
     end
   end
-
-  def replies(activity, opts \\ []) do
-    object = Object.normalize(activity)
-
-    query =
-      Activity
-      |> Queries.by_type("Create")
-      |> Queries.by_object_in_reply_to_id(object.data["id"], skip_preloading: true)
-      |> order_by([activity], asc: activity.id)
-
-    if opts[:self_only] do
-      where(query, [a], a.actor == ^activity.actor)
-    else
-      query
-    end
-  end
-
-  def self_replies(activity, opts \\ []),
-    do: replies(activity, Keyword.put(opts, :self_only, true))
 end
diff --git a/lib/pleroma/object.ex b/lib/pleroma/object.ex
index 52556bf31..f316f8b36 100644
--- a/lib/pleroma/object.ex
+++ b/lib/pleroma/object.ex
@@ -301,4 +301,26 @@ defmodule Pleroma.Object do
   def local?(%Object{data: %{"id" => id}}) do
     String.starts_with?(id, Pleroma.Web.base_url() <> "/")
   end
+
+  def replies(object, opts \\ []) do
+    object = Object.normalize(object)
+
+    query =
+      Object
+      |> where(
+        [o],
+        fragment("(?)->>'inReplyTo' = ?", o.data, ^object.data["id"])
+      )
+      |> order_by([o], asc: o.id)
+
+    if opts[:self_only] do
+      actor = object.data["actor"]
+      where(query, [o], fragment("(?)->>'actor' = ?", o.data, ^actor))
+    else
+      query
+    end
+  end
+
+  def self_replies(object, opts \\ []),
+    do: replies(object, Keyword.put(opts, :self_only, true))
 end
diff --git a/lib/pleroma/web/activity_pub/transmogrifier.ex b/lib/pleroma/web/activity_pub/transmogrifier.ex
index 8266545d1..e89588f29 100644
--- a/lib/pleroma/web/activity_pub/transmogrifier.ex
+++ b/lib/pleroma/web/activity_pub/transmogrifier.ex
@@ -407,7 +407,7 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
     with nil <- Activity.get_create_by_object_ap_id(object["id"]),
          {:ok, %User{} = user} <- User.get_or_fetch_by_ap_id(data["actor"]) do
       options = Keyword.put(options, :depth, (options[:depth] || 0) + 1)
-      object = fix_object(data["object"], options)
+      object = fix_object(object, options)
 
       params = %{
         to: data["to"],
@@ -913,20 +913,20 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
   Serialized Mastodon-compatible `replies` collection containing _self-replies_.
   Based on Mastodon's ActivityPub::NoteSerializer#replies.
   """
-  def set_replies(obj) do
+  def set_replies(obj_data) do
     limit = Pleroma.Config.get([:activitypub, :note_replies_output_limit], 0)
 
     replies_uris =
       with true <- limit > 0 || nil,
-           %Activity{} = activity <- Activity.get_create_by_object_ap_id(obj["id"]) do
-        activity
-        |> Activity.self_replies()
-        |> select([a], fragment("?->>'id'", a.data))
+           %Object{} = object <- Object.get_cached_by_ap_id(obj_data["id"]) do
+        object
+        |> Object.self_replies()
+        |> select([o], fragment("?->>'id'", o.data))
         |> limit(^limit)
         |> Repo.all()
       end
 
-    set_replies(obj, replies_uris || [])
+    set_replies(obj_data, replies_uris || [])
   end
 
   defp set_replies(obj, replies_uris) when replies_uris in [nil, []] do
@@ -952,7 +952,7 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
     Map.merge(obj, %{"replies" => replies_collection})
   end
 
-  def replies(%{"replies" => replies = %{}}) do
+  def replies(%{"replies" => replies} = _object) when is_map(replies) do
     replies =
       if is_map(replies["first"]) do
         replies["first"]
-- 
cgit v1.2.3


From 6ea3c06d8d42cd92b23c6de2d041db1cfea63b5a Mon Sep 17 00:00:00 2001
From: Ivan Tashkinov <ivantashkinov@gmail.com>
Date: Sun, 9 Feb 2020 14:09:01 +0300
Subject: [#1505] Minor refactoring.

---
 lib/pleroma/web/activity_pub/transmogrifier.ex | 24 +++++++++++-------------
 1 file changed, 11 insertions(+), 13 deletions(-)

(limited to 'lib')

diff --git a/lib/pleroma/web/activity_pub/transmogrifier.ex b/lib/pleroma/web/activity_pub/transmogrifier.ex
index e89588f29..343228b37 100644
--- a/lib/pleroma/web/activity_pub/transmogrifier.ex
+++ b/lib/pleroma/web/activity_pub/transmogrifier.ex
@@ -914,22 +914,23 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
   Based on Mastodon's ActivityPub::NoteSerializer#replies.
   """
   def set_replies(obj_data) do
-    limit = Pleroma.Config.get([:activitypub, :note_replies_output_limit], 0)
-
     replies_uris =
-      with true <- limit > 0 || nil,
+      with limit when limit > 0 <-
+             Pleroma.Config.get([:activitypub, :note_replies_output_limit], 0),
            %Object{} = object <- Object.get_cached_by_ap_id(obj_data["id"]) do
         object
         |> Object.self_replies()
         |> select([o], fragment("?->>'id'", o.data))
         |> limit(^limit)
         |> Repo.all()
+      else
+        _ -> []
       end
 
-    set_replies(obj_data, replies_uris || [])
+    set_replies(obj_data, replies_uris)
   end
 
-  defp set_replies(obj, replies_uris) when replies_uris in [nil, []] do
+  defp set_replies(obj, []) do
     obj
   end
 
@@ -952,15 +953,12 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
     Map.merge(obj, %{"replies" => replies_collection})
   end
 
-  def replies(%{"replies" => replies} = _object) when is_map(replies) do
-    replies =
-      if is_map(replies["first"]) do
-        replies["first"]
-      else
-        replies
-      end
+  def replies(%{"replies" => %{"first" => %{"items" => items}}}) when not is_nil(items) do
+    items
+  end
 
-    replies["items"] || []
+  def replies(%{"replies" => %{"items" => items}}) when not is_nil(items) do
+    items
   end
 
   def replies(_), do: []
-- 
cgit v1.2.3


From 24e49d14f287b0daf8c2977f2228be09139e4bf3 Mon Sep 17 00:00:00 2001
From: Ivan Tashkinov <ivantashkinov@gmail.com>
Date: Sun, 9 Feb 2020 17:34:48 +0300
Subject: [#1505] Removed wrapping of reply URIs into `first` element, added
 comments to transmogrifier tests.

---
 lib/pleroma/web/activity_pub/transmogrifier.ex | 12 +-----------
 1 file changed, 1 insertion(+), 11 deletions(-)

(limited to 'lib')

diff --git a/lib/pleroma/web/activity_pub/transmogrifier.ex b/lib/pleroma/web/activity_pub/transmogrifier.ex
index 343228b37..6f09b4994 100644
--- a/lib/pleroma/web/activity_pub/transmogrifier.ex
+++ b/lib/pleroma/web/activity_pub/transmogrifier.ex
@@ -935,19 +935,9 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
   end
 
   defp set_replies(obj, replies_uris) do
-    # Note: stubs (Mastodon doesn't make separate requests via those URIs in FetchRepliesService)
-    masto_replies_uri = nil
-    masto_replies_next_page_uri = nil
-
     replies_collection = %{
       "type" => "Collection",
-      "id" => masto_replies_uri,
-      "first" => %{
-        "type" => "Collection",
-        "part_of" => masto_replies_uri,
-        "items" => replies_uris,
-        "next" => masto_replies_next_page_uri
-      }
+      "items" => replies_uris
     }
 
     Map.merge(obj, %{"replies" => replies_collection})
-- 
cgit v1.2.3


From 269d592181bff8601f6545b85158ee1c222ff20d Mon Sep 17 00:00:00 2001
From: Ivan Tashkinov <ivantashkinov@gmail.com>
Date: Sat, 15 Feb 2020 20:41:38 +0300
Subject: [#1505] Restricted max thread distance for fetching replies on
 incoming federation (in addition to reply-to depth restriction).

---
 lib/pleroma/object/fetcher.ex                  | 20 ++++++++++++--------
 lib/pleroma/web/activity_pub/transmogrifier.ex | 20 ++++++++++++++------
 lib/pleroma/web/federator/federator.ex         | 16 +++++++++++-----
 lib/pleroma/workers/remote_fetcher_worker.ex   |  4 ++--
 4 files changed, 39 insertions(+), 21 deletions(-)

(limited to 'lib')

diff --git a/lib/pleroma/object/fetcher.ex b/lib/pleroma/object/fetcher.ex
index 037c42339..23ecd9e15 100644
--- a/lib/pleroma/object/fetcher.ex
+++ b/lib/pleroma/object/fetcher.ex
@@ -10,6 +10,7 @@ defmodule Pleroma.Object.Fetcher do
   alias Pleroma.Signature
   alias Pleroma.Web.ActivityPub.InternalFetchActor
   alias Pleroma.Web.ActivityPub.Transmogrifier
+  alias Pleroma.Web.Federator
 
   require Logger
   require Pleroma.Constants
@@ -59,20 +60,23 @@ defmodule Pleroma.Object.Fetcher do
     end
   end
 
-  # TODO:
-  # This will create a Create activity, which we need internally at the moment.
+  # Note: will create a Create activity, which we need internally at the moment.
   def fetch_object_from_id(id, options \\ []) do
-    with {:fetch_object, nil} <- {:fetch_object, Object.get_cached_by_ap_id(id)},
-         {:fetch, {:ok, data}} <- {:fetch, fetch_and_contain_remote_object_from_id(id)},
-         {:normalize, nil} <- {:normalize, Object.normalize(data, false)},
+    with {_, nil} <- {:fetch_object, Object.get_cached_by_ap_id(id)},
+         {_, true} <- {:allowed_depth, Federator.allowed_thread_distance?(options[:depth])},
+         {_, {:ok, data}} <- {:fetch, fetch_and_contain_remote_object_from_id(id)},
+         {_, nil} <- {:normalize, Object.normalize(data, false)},
          params <- prepare_activity_params(data),
-         {:containment, :ok} <- {:containment, Containment.contain_origin(id, params)},
-         {:transmogrifier, {:ok, activity}} <-
+         {_, :ok} <- {:containment, Containment.contain_origin(id, params)},
+         {_, {:ok, activity}} <-
            {:transmogrifier, Transmogrifier.handle_incoming(params, options)},
-         {:object, _data, %Object{} = object} <-
+         {_, _data, %Object{} = object} <-
            {:object, data, Object.normalize(activity, false)} do
       {:ok, object}
     else
+      {:allowed_depth, false} ->
+        {:error, "Max thread distance exceeded."}
+
       {:containment, _} ->
         {:error, "Object containment failed."}
 
diff --git a/lib/pleroma/web/activity_pub/transmogrifier.ex b/lib/pleroma/web/activity_pub/transmogrifier.ex
index 6f09b4994..5bd2baca4 100644
--- a/lib/pleroma/web/activity_pub/transmogrifier.ex
+++ b/lib/pleroma/web/activity_pub/transmogrifier.ex
@@ -156,8 +156,9 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
       when not is_nil(in_reply_to) do
     in_reply_to_id = prepare_in_reply_to(in_reply_to)
     object = Map.put(object, "inReplyToAtomUri", in_reply_to_id)
+    depth = (options[:depth] || 0) + 1
 
-    if Federator.allowed_incoming_reply_depth?(options[:depth]) do
+    if Federator.allowed_thread_distance?(depth) do
       with {:ok, replied_object} <- get_obj_helper(in_reply_to_id, options),
            %Activity{} = _ <- Activity.get_create_by_object_ap_id(replied_object.data["id"]) do
         object
@@ -312,7 +313,7 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
 
   def fix_type(%{"inReplyTo" => reply_id, "name" => _} = object, options)
       when is_binary(reply_id) do
-    with true <- Federator.allowed_incoming_reply_depth?(options[:depth]),
+    with true <- Federator.allowed_thread_distance?(options[:depth]),
          {:ok, %{data: %{"type" => "Question"} = _} = _} <- get_obj_helper(reply_id, options) do
       Map.put(object, "type", "Answer")
     else
@@ -406,7 +407,6 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
 
     with nil <- Activity.get_create_by_object_ap_id(object["id"]),
          {:ok, %User{} = user} <- User.get_or_fetch_by_ap_id(data["actor"]) do
-      options = Keyword.put(options, :depth, (options[:depth] || 0) + 1)
       object = fix_object(object, options)
 
       params = %{
@@ -425,8 +425,15 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
       }
 
       with {:ok, created_activity} <- ActivityPub.create(params) do
-        for reply_id <- replies(object) do
-          Pleroma.Workers.RemoteFetcherWorker.enqueue("fetch_remote", %{"id" => reply_id})
+        reply_depth = (options[:depth] || 0) + 1
+
+        if Federator.allowed_thread_distance?(reply_depth) do
+          for reply_id <- replies(object) do
+            Pleroma.Workers.RemoteFetcherWorker.enqueue("fetch_remote", %{
+              "id" => reply_id,
+              "depth" => reply_depth
+            })
+          end
         end
 
         {:ok, created_activity}
@@ -448,7 +455,8 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
       |> fix_addressing
 
     with {:ok, %User{} = user} <- User.get_or_fetch_by_ap_id(data["actor"]) do
-      options = Keyword.put(options, :depth, (options[:depth] || 0) + 1)
+      reply_depth = (options[:depth] || 0) + 1
+      options = Keyword.put(options, :depth, reply_depth)
       object = fix_object(object, options)
 
       params = %{
diff --git a/lib/pleroma/web/federator/federator.ex b/lib/pleroma/web/federator/federator.ex
index f506a7d24..013fb5b70 100644
--- a/lib/pleroma/web/federator/federator.ex
+++ b/lib/pleroma/web/federator/federator.ex
@@ -15,13 +15,19 @@ defmodule Pleroma.Web.Federator do
 
   require Logger
 
-  @doc "Addresses [memory leaks on recursive replies fetching](https://git.pleroma.social/pleroma/pleroma/issues/161)"
+  @doc """
+  Returns `true` if the distance to target object does not exceed max configured value.
+  Serves to prevent fetching of very long threads, especially useful on smaller instances.
+  Addresses [memory leaks on recursive replies fetching](https://git.pleroma.social/pleroma/pleroma/issues/161).
+  Applies to fetching of both ancestor (reply-to) and child (reply) objects.
+  """
   # credo:disable-for-previous-line Credo.Check.Readability.MaxLineLength
-  def allowed_incoming_reply_depth?(depth) do
-    max_replies_depth = Pleroma.Config.get([:instance, :federation_incoming_replies_max_depth])
+  def allowed_thread_distance?(distance) do
+    max_distance = Pleroma.Config.get([:instance, :federation_incoming_replies_max_depth])
 
-    if max_replies_depth do
-      (depth || 1) <= max_replies_depth
+    if max_distance && max_distance >= 0 do
+      # Default depth is 0 (an object has zero distance from itself in its thread)
+      (distance || 0) <= max_distance
     else
       true
     end
diff --git a/lib/pleroma/workers/remote_fetcher_worker.ex b/lib/pleroma/workers/remote_fetcher_worker.ex
index 52db6059b..e860ca869 100644
--- a/lib/pleroma/workers/remote_fetcher_worker.ex
+++ b/lib/pleroma/workers/remote_fetcher_worker.ex
@@ -12,9 +12,9 @@ defmodule Pleroma.Workers.RemoteFetcherWorker do
         %{
           "op" => "fetch_remote",
           "id" => id
-        },
+        } = args,
         _job
       ) do
-    {:ok, _object} = Fetcher.fetch_object_from_id(id)
+    {:ok, _object} = Fetcher.fetch_object_from_id(id, depth: args["depth"])
   end
 end
-- 
cgit v1.2.3


From 343229465753ebcc59002a2dd604a910a8ce462d Mon Sep 17 00:00:00 2001
From: Ivan Tashkinov <ivantashkinov@gmail.com>
Date: Thu, 20 Feb 2020 14:48:46 +0300
Subject: [#1505] Fixed @spec for Queries.by_object_in_reply_to_id/3

---
 lib/pleroma/activity/queries.ex | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'lib')

diff --git a/lib/pleroma/activity/queries.ex b/lib/pleroma/activity/queries.ex
index c17affec9..363727c80 100644
--- a/lib/pleroma/activity/queries.ex
+++ b/lib/pleroma/activity/queries.ex
@@ -63,7 +63,7 @@ defmodule Pleroma.Activity.Queries do
     )
   end
 
-  @spec by_object_id(query, String.t()) :: query
+  @spec by_object_in_reply_to_id(query, String.t(), keyword()) :: query
   def by_object_in_reply_to_id(query, in_reply_to_id, opts \\ []) do
     query =
       if opts[:skip_preloading] do
-- 
cgit v1.2.3