Merge branch 'feature/hide-follows-remote' into 'develop'

Refactor Follows/Followers counter syncronization and set hide_followers/hide_follows for remote users

See merge request pleroma/pleroma!1411

12 files changed, 326 insertions, 89 deletions

diff --git a/config/test.exs b/config/test.exs
index 92dca18bc..aded8600d 100644
--- a/config/test.exs
+++ b/config/test.exs
@@ -29,7 +29,8 @@ config :pleroma, :instance,
   email: "admin@example.com",
   notify_email: "noreply@example.com",
   skip_thread_containment: false,
-  federating: false
+  federating: false,
+  external_user_synchronization: false
 
 config :pleroma, :activitypub, sign_object_fetches: false
 
diff --git a/lib/pleroma/object/fetcher.ex b/lib/pleroma/object/fetcher.ex
index 305ce8357..8d79ddb1f 100644
--- a/lib/pleroma/object/fetcher.ex
+++ b/lib/pleroma/object/fetcher.ex
@@ -114,7 +114,7 @@ defmodule Pleroma.Object.Fetcher do
     end
   end
 
-  def fetch_and_contain_remote_object_from_id(id) do
+  def fetch_and_contain_remote_object_from_id(id) when is_binary(id) do
     Logger.info("Fetching object #{id} via AP")
 
     date =
@@ -141,4 +141,9 @@ defmodule Pleroma.Object.Fetcher do
         {:error, e}
     end
   end
+
+  def fetch_and_contain_remote_object_from_id(%{"id" => id}),
+    do: fetch_and_contain_remote_object_from_id(id)
+
+  def fetch_and_contain_remote_object_from_id(_id), do: {:error, "id must be a string"}
 end
diff --git a/lib/pleroma/user.ex b/lib/pleroma/user.ex
index 1adb82f32..974f96852 100644
--- a/lib/pleroma/user.ex
+++ b/lib/pleroma/user.ex
@@ -114,7 +114,9 @@ defmodule Pleroma.User do
 
   def user_info(%User{} = user, args \\ %{}) do
     following_count =
-      if args[:following_count], do: args[:following_count], else: following_count(user)
+      if args[:following_count],
+        do: args[:following_count],
+        else: user.info.following_count || following_count(user)
 
     follower_count =
       if args[:follower_count], do: args[:follower_count], else: user.info.follower_count
@@ -406,6 +408,8 @@ defmodule Pleroma.User do
 
         {1, [follower]} = Repo.update_all(q, [])
 
+        follower = maybe_update_following_count(follower)
+
         {:ok, _} = update_follower_count(followed)
 
         set_cache(follower)
@@ -425,6 +429,8 @@ defmodule Pleroma.User do
 
       {1, [follower]} = Repo.update_all(q, [])
 
+      follower = maybe_update_following_count(follower)
+
       {:ok, followed} = update_follower_count(followed)
 
       set_cache(follower)
@@ -709,32 +715,73 @@ defmodule Pleroma.User do
     |> update_and_set_cache()
   end
 
+  def maybe_fetch_follow_information(user) do
+    with {:ok, user} <- fetch_follow_information(user) do
+      user
+    else
+      e ->
+        Logger.error("Follower/Following counter update for #{user.ap_id} failed.\n#{inspect(e)}")
+
+        user
+    end
+  end
+
+  def fetch_follow_information(user) do
+    with {:ok, info} <- ActivityPub.fetch_follow_information_for_user(user) do
+      info_cng = User.Info.follow_information_update(user.info, info)
+
+      changeset =
+        user
+        |> change()
+        |> put_embed(:info, info_cng)
+
+      update_and_set_cache(changeset)
+    else
+      {:error, _} = e -> e
+      e -> {:error, e}
+    end
+  end
+
   def update_follower_count(%User{} = user) do
-    follower_count_query =
-      User.Query.build(%{followers: user, deactivated: false})
-      |> select([u], %{count: count(u.id)})
+    if user.local or !Pleroma.Config.get([:instance, :external_user_synchronization]) do
+      follower_count_query =
+        User.Query.build(%{followers: user, deactivated: false})
+        |> select([u], %{count: count(u.id)})
+
+      User
+      |> where(id: ^user.id)
+      |> join(:inner, [u], s in subquery(follower_count_query))
+      |> update([u, s],
+        set: [
+          info:
+            fragment(
+              "jsonb_set(?, '{follower_count}', ?::varchar::jsonb, true)",
+              u.info,
+              s.count
+            )
+        ]
+      )
+      |> select([u], u)
+      |> Repo.update_all([])
+      |> case do
+        {1, [user]} -> set_cache(user)
+        _ -> {:error, user}
+      end
+    else
+      {:ok, maybe_fetch_follow_information(user)}
+    end
+  end
 
-    User
-    |> where(id: ^user.id)
-    |> join(:inner, [u], s in subquery(follower_count_query))
-    |> update([u, s],
-      set: [
-        info:
-          fragment(
-            "jsonb_set(?, '{follower_count}', ?::varchar::jsonb, true)",
-            u.info,
-            s.count
-          )
-      ]
-    )
-    |> select([u], u)
-    |> Repo.update_all([])
-    |> case do
-      {1, [user]} -> set_cache(user)
-      _ -> {:error, user}
+  def maybe_update_following_count(%User{local: false} = user) do
+    if Pleroma.Config.get([:instance, :external_user_synchronization]) do
+      {:ok, maybe_fetch_follow_information(user)}
+    else
+      user
     end
   end
 
+  def maybe_update_following_count(user), do: user
+
   def remove_duplicated_following(%User{following: following} = user) do
     uniq_following = Enum.uniq(following)
 
diff --git a/lib/pleroma/user/info.ex b/lib/pleroma/user/info.ex
index 9beb3ddbd..b03e705c3 100644
--- a/lib/pleroma/user/info.ex
+++ b/lib/pleroma/user/info.ex
@@ -16,6 +16,8 @@ defmodule Pleroma.User.Info do
     field(:source_data, :map, default: %{})
     field(:note_count, :integer, default: 0)
     field(:follower_count, :integer, default: 0)
+    # Should be filled in only for remote users
+    field(:following_count, :integer, default: nil)
     field(:locked, :boolean, default: false)
     field(:confirmation_pending, :boolean, default: false)
     field(:confirmation_token, :string, default: nil)
@@ -223,7 +225,11 @@ defmodule Pleroma.User.Info do
       :uri,
       :hub,
       :topic,
-      :salmon
+      :salmon,
+      :hide_followers,
+      :hide_follows,
+      :follower_count,
+      :following_count
     ])
   end
 
@@ -234,7 +240,11 @@ defmodule Pleroma.User.Info do
       :source_data,
       :banner,
       :locked,
-      :magic_key
+      :magic_key,
+      :follower_count,
+      :following_count,
+      :hide_follows,
+      :hide_followers
     ])
   end
 
@@ -348,4 +358,14 @@ defmodule Pleroma.User.Info do
 
     cast(info, params, [:muted_reblogs])
   end
+
+  def follow_information_update(info, params) do
+    info
+    |> cast(params, [
+      :hide_followers,
+      :hide_follows,
+      :follower_count,
+      :following_count
+    ])
+  end
 end
diff --git a/lib/pleroma/web/activity_pub/activity_pub.ex b/lib/pleroma/web/activity_pub/activity_pub.ex
index 6fd7fef92..07a65127b 100644
--- a/lib/pleroma/web/activity_pub/activity_pub.ex
+++ b/lib/pleroma/web/activity_pub/activity_pub.ex
@@ -1009,10 +1009,10 @@ defmodule Pleroma.Web.ActivityPub.ActivityPub do
     user_data = %{
       ap_id: data["id"],
       info: %{
-        "ap_enabled" => true,
-        "source_data" => data,
-        "banner" => banner,
-        "locked" => locked
+        ap_enabled: true,
+        source_data: data,
+        banner: banner,
+        locked: locked
       },
       avatar: avatar,
       name: data["name"],
@@ -1036,6 +1036,71 @@ defmodule Pleroma.Web.ActivityPub.ActivityPub do
     {:ok, user_data}
   end
 
+  def fetch_follow_information_for_user(user) do
+    with {:ok, following_data} <-
+           Fetcher.fetch_and_contain_remote_object_from_id(user.following_address),
+         following_count when is_integer(following_count) <- following_data["totalItems"],
+         {:ok, hide_follows} <- collection_private(following_data),
+         {:ok, followers_data} <-
+           Fetcher.fetch_and_contain_remote_object_from_id(user.follower_address),
+         followers_count when is_integer(followers_count) <- followers_data["totalItems"],
+         {:ok, hide_followers} <- collection_private(followers_data) do
+      {:ok,
+       %{
+         hide_follows: hide_follows,
+         follower_count: followers_count,
+         following_count: following_count,
+         hide_followers: hide_followers
+       }}
+    else
+      {:error, _} = e ->
+        e
+
+      e ->
+        {:error, e}
+    end
+  end
+
+  defp maybe_update_follow_information(data) do
+    with {:enabled, true} <-
+           {:enabled, Pleroma.Config.get([:instance, :external_user_synchronization])},
+         {:ok, info} <- fetch_follow_information_for_user(data) do
+      info = Map.merge(data.info, info)
+      Map.put(data, :info, info)
+    else
+      {:enabled, false} ->
+        data
+
+      e ->
+        Logger.error(
+          "Follower/Following counter update for #{data.ap_id} failed.\n" <> inspect(e)
+        )
+
+        data
+    end
+  end
+
+  defp collection_private(data) do
+    if is_map(data["first"]) and
+         data["first"]["type"] in ["CollectionPage", "OrderedCollectionPage"] do
+      {:ok, false}
+    else
+      with {:ok, %{"type" => type}} when type in ["CollectionPage", "OrderedCollectionPage"] <-
+             Fetcher.fetch_and_contain_remote_object_from_id(data["first"]) do
+        {:ok, false}
+      else
+        {:error, {:ok, %{status: code}}} when code in [401, 403] ->
+          {:ok, true}
+
+        {:error, _} = e ->
+          e
+
+        e ->
+          {:error, e}
+      end
+    end
+  end
+
   def user_data_from_user_object(data) do
     with {:ok, data} <- MRF.filter(data),
          {:ok, data} <- object_to_user_data(data) do
@@ -1047,7 +1112,8 @@ defmodule Pleroma.Web.ActivityPub.ActivityPub do
 
   def fetch_and_prepare_user_from_ap_id(ap_id) do
     with {:ok, data} <- Fetcher.fetch_and_contain_remote_object_from_id(ap_id),
-         {:ok, data} <- user_data_from_user_object(data) do
+         {:ok, data} <- user_data_from_user_object(data),
+         data <- maybe_update_follow_information(data) do
       {:ok, data}
     else
       e -> Logger.error("Could not decode user at fetch #{ap_id}, #{inspect(e)}")
diff --git a/lib/pleroma/web/activity_pub/transmogrifier.ex b/lib/pleroma/web/activity_pub/transmogrifier.ex
index 44bb1cb9a..5403b71d8 100644
--- a/lib/pleroma/web/activity_pub/transmogrifier.ex
+++ b/lib/pleroma/web/activity_pub/transmogrifier.ex
@@ -608,13 +608,13 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
     with %User{ap_id: ^actor_id} = actor <- User.get_cached_by_ap_id(object["id"]) do
       {:ok, new_user_data} = ActivityPub.user_data_from_user_object(object)
 
-      banner = new_user_data[:info]["banner"]
-      locked = new_user_data[:info]["locked"] || false
+      banner = new_user_data[:info][:banner]
+      locked = new_user_data[:info][:locked] || false
 
       update_data =
         new_user_data
         |> Map.take([:name, :bio, :avatar])
-        |> Map.put(:info, %{"banner" => banner, "locked" => locked})
+        |> Map.put(:info, %{banner: banner, locked: locked})
 
       actor
       |> User.upgrade_changeset(update_data)
@@ -1076,10 +1076,6 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
         PleromaJobQueue.enqueue(:transmogrifier, __MODULE__, [:user_upgrade, user])
       end
 
-      if Pleroma.Config.get([:instance, :external_user_synchronization]) do
-        update_following_followers_counters(user)
-      end
-
       {:ok, user}
     else
       %User{} = user -> {:ok, user}
@@ -1112,27 +1108,4 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
     data
     |> maybe_fix_user_url
   end
-
-  def update_following_followers_counters(user) do
-    info = %{}
-
-    following = fetch_counter(user.following_address)
-    info = if following, do: Map.put(info, :following_count, following), else: info
-
-    followers = fetch_counter(user.follower_address)
-    info = if followers, do: Map.put(info, :follower_count, followers), else: info
-
-    User.set_info_cache(user, info)
-  end
-
-  defp fetch_counter(url) do
-    with {:ok, %{body: body, status: code}} when code in 200..299 <-
-           Pleroma.HTTP.get(
-             url,
-             [{:Accept, "application/activity+json"}]
-           ),
-         {:ok, data} <- Jason.decode(body) do
-      data["totalItems"]
-    end
-  end
 end
diff --git a/test/fixtures/users_mock/masto_closed_followers_page.json b/test/fixtures/users_mock/masto_closed_followers_page.json
new file mode 100644
index 000000000..04ab0c4d3
--- /dev/null
+++ b/test/fixtures/users_mock/masto_closed_followers_page.json
@@ -0,0 +1 @@
+{"@context":"https://www.w3.org/ns/activitystreams","id":"http://localhost:4001/users/masto_closed/followers?page=1","type":"OrderedCollectionPage","totalItems":437,"next":"http://localhost:4001/users/masto_closed/followers?page=2","partOf":"http://localhost:4001/users/masto_closed/followers","orderedItems":["https://testing.uguu.ltd/users/rin","https://patch.cx/users/rin","https://letsalllovela.in/users/xoxo","https://pleroma.site/users/crushv","https://aria.company/users/boris","https://kawen.space/users/crushv","https://freespeech.host/users/cvcvcv","https://pleroma.site/users/picpub","https://pixelfed.social/users/nosleep","https://boopsnoot.gq/users/5c1896d162f7d337f90492a3","https://pikachu.rocks/users/waifu","https://royal.crablettesare.life/users/crablettes"]}
diff --git a/test/fixtures/users_mock/masto_closed_following_page.json b/test/fixtures/users_mock/masto_closed_following_page.json
new file mode 100644
index 000000000..8d8324699
--- /dev/null
+++ b/test/fixtures/users_mock/masto_closed_following_page.json
@@ -0,0 +1 @@
+{"@context":"https://www.w3.org/ns/activitystreams","id":"http://localhost:4001/users/masto_closed/following?page=1","type":"OrderedCollectionPage","totalItems":152,"next":"http://localhost:4001/users/masto_closed/following?page=2","partOf":"http://localhost:4001/users/masto_closed/following","orderedItems":["https://testing.uguu.ltd/users/rin","https://patch.cx/users/rin","https://letsalllovela.in/users/xoxo","https://pleroma.site/users/crushv","https://aria.company/users/boris","https://kawen.space/users/crushv","https://freespeech.host/users/cvcvcv","https://pleroma.site/users/picpub","https://pixelfed.social/users/nosleep","https://boopsnoot.gq/users/5c1896d162f7d337f90492a3","https://pikachu.rocks/users/waifu","https://royal.crablettesare.life/users/crablettes"]}
diff --git a/test/support/http_request_mock.ex b/test/support/http_request_mock.ex
index d767ab9d4..3adb5ba3b 100644
--- a/test/support/http_request_mock.ex
+++ b/test/support/http_request_mock.ex
@@ -796,6 +796,14 @@ defmodule HttpRequestMock do
      }}
   end
 
+  def get("http://localhost:4001/users/masto_closed/followers?page=1", _, _, _) do
+    {:ok,
+     %Tesla.Env{
+       status: 200,
+       body: File.read!("test/fixtures/users_mock/masto_closed_followers_page.json")
+     }}
+  end
+
   def get("http://localhost:4001/users/masto_closed/following", _, _, _) do
     {:ok,
      %Tesla.Env{
@@ -804,6 +812,14 @@ defmodule HttpRequestMock do
      }}
   end
 
+  def get("http://localhost:4001/users/masto_closed/following?page=1", _, _, _) do
+    {:ok,
+     %Tesla.Env{
+       status: 200,
+       body: File.read!("test/fixtures/users_mock/masto_closed_following_page.json")
+     }}
+  end
+
   def get("http://localhost:4001/users/fuser2/followers", _, _, _) do
     {:ok,
      %Tesla.Env{
diff --git a/test/user_test.exs b/test/user_test.exs
index 556df45fd..7ec241c25 100644
--- a/test/user_test.exs
+++ b/test/user_test.exs
@@ -1393,4 +1393,78 @@ defmodule Pleroma.UserTest do
       assert %User{bio: "test-bio"} = User.get_cached_by_ap_id(user.ap_id)
     end
   end
+
+  describe "following/followers synchronization" do
+    setup do
+      sync = Pleroma.Config.get([:instance, :external_user_synchronization])
+      on_exit(fn -> Pleroma.Config.put([:instance, :external_user_synchronization], sync) end)
+    end
+
+    test "updates the counters normally on following/getting a follow when disabled" do
+      Pleroma.Config.put([:instance, :external_user_synchronization], false)
+      user = insert(:user)
+
+      other_user =
+        insert(:user,
+          local: false,
+          follower_address: "http://localhost:4001/users/masto_closed/followers",
+          following_address: "http://localhost:4001/users/masto_closed/following",
+          info: %{ap_enabled: true}
+        )
+
+      assert User.user_info(other_user).following_count == 0
+      assert User.user_info(other_user).follower_count == 0
+
+      {:ok, user} = Pleroma.User.follow(user, other_user)
+      other_user = Pleroma.User.get_by_id(other_user.id)
+
+      assert User.user_info(user).following_count == 1
+      assert User.user_info(other_user).follower_count == 1
+    end
+
+    test "syncronizes the counters with the remote instance for the followed when enabled" do
+      Pleroma.Config.put([:instance, :external_user_synchronization], false)
+
+      user = insert(:user)
+
+      other_user =
+        insert(:user,
+          local: false,
+          follower_address: "http://localhost:4001/users/masto_closed/followers",
+          following_address: "http://localhost:4001/users/masto_closed/following",
+          info: %{ap_enabled: true}
+        )
+
+      assert User.user_info(other_user).following_count == 0
+      assert User.user_info(other_user).follower_count == 0
+
+      Pleroma.Config.put([:instance, :external_user_synchronization], true)
+      {:ok, _user} = User.follow(user, other_user)
+      other_user = User.get_by_id(other_user.id)
+
+      assert User.user_info(other_user).follower_count == 437
+    end
+
+    test "syncronizes the counters with the remote instance for the follower when enabled" do
+      Pleroma.Config.put([:instance, :external_user_synchronization], false)
+
+      user = insert(:user)
+
+      other_user =
+        insert(:user,
+          local: false,
+          follower_address: "http://localhost:4001/users/masto_closed/followers",
+          following_address: "http://localhost:4001/users/masto_closed/following",
+          info: %{ap_enabled: true}
+        )
+
+      assert User.user_info(other_user).following_count == 0
+      assert User.user_info(other_user).follower_count == 0
+
+      Pleroma.Config.put([:instance, :external_user_synchronization], true)
+      {:ok, other_user} = User.follow(other_user, user)
+
+      assert User.user_info(other_user).following_count == 152
+    end
+  end
 end
diff --git a/test/web/activity_pub/activity_pub_test.exs b/test/web/activity_pub/activity_pub_test.exs
index 1c0b274cb..3d9a678dd 100644
--- a/test/web/activity_pub/activity_pub_test.exs
+++ b/test/web/activity_pub/activity_pub_test.exs
@@ -1128,4 +1128,65 @@ defmodule Pleroma.Web.ActivityPub.ActivityPubTest do
       assert result.id == activity.id
     end
   end
+
+  describe "fetch_follow_information_for_user" do
+    test "syncronizes following/followers counters" do
+      user =
+        insert(:user,
+          local: false,
+          follower_address: "http://localhost:4001/users/fuser2/followers",
+          following_address: "http://localhost:4001/users/fuser2/following"
+        )
+
+      {:ok, info} = ActivityPub.fetch_follow_information_for_user(user)
+      assert info.follower_count == 527
+      assert info.following_count == 267
+    end
+
+    test "detects hidden followers" do
+      mock(fn env ->
+        case env.url do
+          "http://localhost:4001/users/masto_closed/followers?page=1" ->
+            %Tesla.Env{status: 403, body: ""}
+
+          _ ->
+            apply(HttpRequestMock, :request, [env])
+        end
+      end)
+
+      user =
+        insert(:user,
+          local: false,
+          follower_address: "http://localhost:4001/users/masto_closed/followers",
+          following_address: "http://localhost:4001/users/masto_closed/following"
+        )
+
+      {:ok, info} = ActivityPub.fetch_follow_information_for_user(user)
+      assert info.hide_followers == true
+      assert info.hide_follows == false
+    end
+
+    test "detects hidden follows" do
+      mock(fn env ->
+        case env.url do
+          "http://localhost:4001/users/masto_closed/following?page=1" ->
+            %Tesla.Env{status: 403, body: ""}
+
+          _ ->
+            apply(HttpRequestMock, :request, [env])
+        end
+      end)
+
+      user =
+        insert(:user,
+          local: false,
+          follower_address: "http://localhost:4001/users/masto_closed/followers",
+          following_address: "http://localhost:4001/users/masto_closed/following"
+        )
+
+      {:ok, info} = ActivityPub.fetch_follow_information_for_user(user)
+      assert info.hide_followers == false
+      assert info.hide_follows == true
+    end
+  end
 end
diff --git a/test/web/activity_pub/transmogrifier_test.exs b/test/web/activity_pub/transmogrifier_test.exs
index a1f5f6e36..e7498e005 100644
--- a/test/web/activity_pub/transmogrifier_test.exs
+++ b/test/web/activity_pub/transmogrifier_test.exs
@@ -1373,32 +1373,4 @@ defmodule Pleroma.Web.ActivityPub.TransmogrifierTest do
       refute recipient.follower_address in fixed_object["to"]
     end
   end
-
-  test "update_following_followers_counters/1" do
-    user1 =
-      insert(:user,
-        local: false,
-        follower_address: "http://localhost:4001/users/masto_closed/followers",
-        following_address: "http://localhost:4001/users/masto_closed/following"
-      )
-
-    user2 =
-      insert(:user,
-        local: false,
-        follower_address: "http://localhost:4001/users/fuser2/followers",
-        following_address: "http://localhost:4001/users/fuser2/following"
-      )
-
-    Transmogrifier.update_following_followers_counters(user1)
-    Transmogrifier.update_following_followers_counters(user2)
-
-    %{follower_count: followers, following_count: following} = User.get_cached_user_info(user1)
-    assert followers == 437
-    assert following == 152
-
-    %{follower_count: followers, following_count: following} = User.get_cached_user_info(user2)
-
-    assert followers == 527
-    assert following == 267
-  end
 end