Merge branch 'post-languages' into 'develop'

Allow to specify post language

See merge request pleroma/pleroma!3940

changelog.d/post-languages.add

@@ -0,0 +1 @@
+Allow to specify post language

lib/pleroma/constants.ex

@@ -20,7 +20,8 @@ defmodule Pleroma.Constants do
       "deleted_activity_id",
       "pleroma_internal",
       "generator",
-      "rules"
+      "rules",
+      "language"
     ]
   )
 
@@ -36,10 +37,12 @@ defmodule Pleroma.Constants do
       "updated",
       "emoji",
       "content",
+      "contentMap",
       "summary",
       "sensitive",
       "attachment",
-      "generator"
+      "generator",
+      "language"
     ]
   )
 

lib/pleroma/ecto_type/activity_pub/object_validators/content_language_map.ex

@@ -0,0 +1,49 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2023 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.EctoType.ActivityPub.ObjectValidators.ContentLanguageMap do
+  use Ecto.Type
+
+  import Pleroma.EctoType.ActivityPub.ObjectValidators.LanguageCode,
+    only: [good_locale_code?: 1]
+
+  def type, do: :map
+
+  def cast(%{} = object) do
+    with {status, %{} = data} when status in [:modified, :ok] <- validate_map(object) do
+      {:ok, data}
+    else
+      {_, nil} -> {:ok, nil}
+      {:error, _} -> :error
+    end
+  end
+
+  def cast(_), do: :error
+
+  def dump(data), do: {:ok, data}
+
+  def load(data), do: {:ok, data}
+
+  defp validate_map(%{} = object) do
+    {status, data} =
+      object
+      |> Enum.reduce({:ok, %{}}, fn
+        {lang, value}, {status, acc} when is_binary(lang) and is_binary(value) ->
+          if good_locale_code?(lang) do
+            {status, Map.put(acc, lang, value)}
+          else
+            {:modified, acc}
+          end
+
+        _, {_status, acc} ->
+          {:modified, acc}
+      end)
+
+    if data == %{} do
+      {status, nil}
+    else
+      {status, data}
+    end
+  end
+end

lib/pleroma/ecto_type/activity_pub/object_validators/language_code.ex

@@ -0,0 +1,27 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2023 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.EctoType.ActivityPub.ObjectValidators.LanguageCode do
+  use Ecto.Type
+
+  def type, do: :string
+
+  def cast(language) when is_binary(language) do
+    if good_locale_code?(language) do
+      {:ok, language}
+    else
+      {:error, :invalid_language}
+    end
+  end
+
+  def cast(_), do: :error
+
+  def dump(data), do: {:ok, data}
+
+  def load(data), do: {:ok, data}
+
+  def good_locale_code?(code) when is_binary(code), do: code =~ ~r<^[a-zA-Z0-9\-]+\z$>
+
+  def good_locale_code?(_code), do: false
+end

lib/pleroma/web/activity_pub/object_validator.ex

@@ -26,6 +26,7 @@ defmodule Pleroma.Web.ActivityPub.ObjectValidator do
   alias Pleroma.Web.ActivityPub.ObjectValidators.AudioImageVideoValidator
   alias Pleroma.Web.ActivityPub.ObjectValidators.BlockValidator
   alias Pleroma.Web.ActivityPub.ObjectValidators.ChatMessageValidator
+  alias Pleroma.Web.ActivityPub.ObjectValidators.CommonFixes
   alias Pleroma.Web.ActivityPub.ObjectValidators.CreateChatMessageValidator
   alias Pleroma.Web.ActivityPub.ObjectValidators.CreateGenericValidator
   alias Pleroma.Web.ActivityPub.ObjectValidators.DeleteValidator
@@ -115,7 +116,10 @@ defmodule Pleroma.Web.ActivityPub.ObjectValidator do
         meta
       )
       when objtype in ~w[Question Answer Audio Video Image Event Article Note Page] do
-    with {:ok, object_data} <- cast_and_apply_and_stringify_with_history(object),
+    with {:ok, object_data} <-
+           object
+           |> CommonFixes.maybe_add_language_from_activity(create_activity)
+           |> cast_and_apply_and_stringify_with_history(),
          meta = Keyword.put(meta, :object_data, object_data),
          {:ok, create_activity} <-
            create_activity
@@ -165,7 +169,11 @@ defmodule Pleroma.Web.ActivityPub.ObjectValidator do
       )
       when objtype in ~w[Question Answer Audio Video Event Article Note Page] do
     with {_, false} <- {:local, Access.get(meta, :local, false)},
-         {_, {:ok, object_data, _}} <- {:object_validation, validate(object, meta)},
+         {_, {:ok, object_data, _}} <-
+           {:object_validation,
+            object
+            |> CommonFixes.maybe_add_language_from_activity(update_activity)
+            |> validate(meta)},
          meta = Keyword.put(meta, :object_data, object_data),
          {:ok, update_activity} <-
            update_activity

lib/pleroma/web/activity_pub/object_validators/article_note_page_validator.ex

@@ -30,7 +30,7 @@ defmodule Pleroma.Web.ActivityPub.ObjectValidators.ArticleNotePageValidator do
 
   def cast_and_apply(data) do
     data
-    |> cast_data
+    |> cast_data()
     |> apply_action(:insert)
   end
 
@@ -88,6 +88,8 @@ defmodule Pleroma.Web.ActivityPub.ObjectValidators.ArticleNotePageValidator do
     |> CommonFixes.fix_likes()
     |> Transmogrifier.fix_emoji()
     |> Transmogrifier.fix_content_map()
+    |> CommonFixes.maybe_add_language()
+    |> CommonFixes.maybe_add_content_map()
   end
 
   def changeset(struct, data) do

lib/pleroma/web/activity_pub/object_validators/common_fields.ex

@@ -31,6 +31,7 @@ defmodule Pleroma.Web.ActivityPub.ObjectValidators.CommonFields do
   defmacro object_fields do
     quote bind_quoted: binding() do
       field(:content, :string)
+      field(:contentMap, ObjectValidators.ContentLanguageMap)
 
       field(:published, ObjectValidators.DateTime)
       field(:updated, ObjectValidators.DateTime)
@@ -58,6 +59,7 @@ defmodule Pleroma.Web.ActivityPub.ObjectValidators.CommonFields do
       field(:like_count, :integer, default: 0)
       field(:announcement_count, :integer, default: 0)
       field(:quotes_count, :integer, default: 0)
+      field(:language, ObjectValidators.LanguageCode)
       field(:inReplyTo, ObjectValidators.ObjectID)
       field(:quoteUrl, ObjectValidators.ObjectID)
       field(:url, ObjectValidators.BareUri)

lib/pleroma/web/activity_pub/object_validators/common_fixes.ex

@@ -11,6 +11,11 @@ defmodule Pleroma.Web.ActivityPub.ObjectValidators.CommonFixes do
   alias Pleroma.Web.ActivityPub.Transmogrifier
   alias Pleroma.Web.ActivityPub.Utils
 
+  import Pleroma.EctoType.ActivityPub.ObjectValidators.LanguageCode,
+    only: [good_locale_code?: 1]
+
+  import Pleroma.Web.Utils.Guards, only: [not_empty_string: 1]
+
   require Pleroma.Constants
 
   def cast_and_filter_recipients(message, field, follower_collection, field_fallback \\ []) do
@@ -132,4 +137,60 @@ defmodule Pleroma.Web.ActivityPub.ObjectValidators.CommonFixes do
   end
 
   def object_link_tag?(_), do: false
+
+  def maybe_add_language_from_activity(object, activity) do
+    language = get_language_from_context(activity)
+
+    if language do
+      Map.put(object, "language", language)
+    else
+      object
+    end
+  end
+
+  def maybe_add_language(object) do
+    language =
+      [
+        get_language_from_context(object),
+        get_language_from_content_map(object)
+      ]
+      |> Enum.find(&good_locale_code?(&1))
+
+    if language do
+      Map.put(object, "language", language)
+    else
+      object
+    end
+  end
+
+  defp get_language_from_context(%{"@context" => context}) when is_list(context) do
+    case context
+         |> Enum.find(fn
+           %{"@language" => language} -> language != "und"
+           _ -> nil
+         end) do
+      %{"@language" => language} -> language
+      _ -> nil
+    end
+  end
+
+  defp get_language_from_context(_), do: nil
+
+  defp get_language_from_content_map(%{"contentMap" => content_map, "content" => source_content}) do
+    content_groups = Map.to_list(content_map)
+
+    case Enum.find(content_groups, fn {_, content} -> content == source_content end) do
+      {language, _} -> language
+      _ -> nil
+    end
+  end
+
+  defp get_language_from_content_map(_), do: nil
+
+  def maybe_add_content_map(%{"language" => language, "content" => content} = object)
+      when not_empty_string(language) do
+    Map.put(object, "contentMap", Map.put(%{}, language, content))
+  end
+
+  def maybe_add_content_map(object), do: object
 end

lib/pleroma/web/activity_pub/object_validators/event_validator.ex

@@ -28,7 +28,7 @@ defmodule Pleroma.Web.ActivityPub.ObjectValidators.EventValidator do
 
   def cast_and_apply(data) do
     data
-    |> cast_data
+    |> cast_data()
     |> apply_action(:insert)
   end
 
@@ -38,6 +38,7 @@ defmodule Pleroma.Web.ActivityPub.ObjectValidators.EventValidator do
     |> validate_data()
   end
 
+  @spec cast_data(map()) :: map()
   def cast_data(data) do
     %__MODULE__{}
     |> changeset(data)
@@ -49,6 +50,8 @@ defmodule Pleroma.Web.ActivityPub.ObjectValidators.EventValidator do
     |> CommonFixes.fix_object_defaults()
     |> CommonFixes.fix_likes()
     |> Transmogrifier.fix_emoji()
+    |> CommonFixes.maybe_add_language()
+    |> CommonFixes.maybe_add_content_map()
   end
 
   def changeset(struct, data) do

lib/pleroma/web/activity_pub/transmogrifier.ex

@@ -16,12 +16,14 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
   alias Pleroma.Web.ActivityPub.ActivityPub
   alias Pleroma.Web.ActivityPub.Builder
   alias Pleroma.Web.ActivityPub.ObjectValidator
+  alias Pleroma.Web.ActivityPub.ObjectValidators.CommonFixes
   alias Pleroma.Web.ActivityPub.Pipeline
   alias Pleroma.Web.ActivityPub.Utils
   alias Pleroma.Web.ActivityPub.Visibility
   alias Pleroma.Web.Federator
 
   import Ecto.Query
+  import Pleroma.Web.Utils.Guards, only: [not_empty_string: 1]
 
   require Pleroma.Constants
 
@@ -166,7 +168,7 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
 
   def fix_quote_url_and_maybe_fetch(object, options \\ []) do
     quote_url =
-      case Pleroma.Web.ActivityPub.ObjectValidators.CommonFixes.fix_quote_url(object) do
+      case CommonFixes.fix_quote_url(object) do
         %{"quoteUrl" => quote_url} -> quote_url
         _ -> nil
       end
@@ -336,6 +338,9 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
 
   def fix_tag(object), do: object
 
+  # prefer content over contentMap
+  def fix_content_map(%{"content" => content} = object) when not_empty_string(content), do: object
+
   # content map usually only has one language so this will do for now.
   def fix_content_map(%{"contentMap" => content_map} = object) do
     content_groups = Map.to_list(content_map)
@@ -716,6 +721,7 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
     |> set_reply_to_uri
     |> set_quote_url
     |> set_replies
+    |> CommonFixes.maybe_add_content_map()
     |> strip_internal_fields
     |> strip_internal_tags
     |> set_type
@@ -750,12 +756,11 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
       object_id
       |> Object.normalize(fetch: false)
       |> Map.get(:data)
-      |> prepare_object
 
     data =
       data
-      |> Map.put("object", object)
+      |> Map.put("object", prepare_object(object))
-      |> Map.merge(Utils.make_json_ld_header())
+      |> Map.merge(Utils.make_json_ld_header(object))
       |> Map.delete("bcc")
 
     {:ok, data}
@@ -763,14 +768,10 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
 
   def prepare_outgoing(%{"type" => "Update", "object" => %{"type" => objtype} = object} = data)
       when objtype in Pleroma.Constants.updatable_object_types() do
-    object =
-      object
-      |> prepare_object
-
     data =
       data
-      |> Map.put("object", object)
+      |> Map.put("object", prepare_object(object))
-      |> Map.merge(Utils.make_json_ld_header())
+      |> Map.merge(Utils.make_json_ld_header(object))
       |> Map.delete("bcc")
 
     {:ok, data}
@@ -840,7 +841,7 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
       data
       |> strip_internal_fields
       |> maybe_fix_object_url
-      |> Map.merge(Utils.make_json_ld_header())
+      |> Map.merge(Utils.make_json_ld_header(data))
 
     {:ok, data}
   end

lib/pleroma/web/activity_pub/utils.ex

@@ -20,6 +20,7 @@ defmodule Pleroma.Web.ActivityPub.Utils do
   alias Pleroma.Web.Router.Helpers
 
   import Ecto.Query
+  import Pleroma.Web.Utils.Guards, only: [not_empty_string: 1]
 
   require Logger
   require Pleroma.Constants
@@ -109,18 +110,24 @@ defmodule Pleroma.Web.ActivityPub.Utils do
     end
   end
 
-  def make_json_ld_header do
+  def make_json_ld_header(data \\ %{}) do
     %{
       "@context" => [
         "https://www.w3.org/ns/activitystreams",
         "#{Endpoint.url()}/schemas/litepub-0.1.jsonld",
         %{
-          "@language" => "und"
+          "@language" => get_language(data)
         }
       ]
     }
   end
 
+  defp get_language(%{"language" => language}) when not_empty_string(language) do
+    language
+  end
+
+  defp get_language(_), do: "und"
+
   def make_date do
     DateTime.utc_now() |> DateTime.to_iso8601()
   end

lib/pleroma/web/activity_pub/views/object_view.ex

@@ -9,7 +9,7 @@ defmodule Pleroma.Web.ActivityPub.ObjectView do
   alias Pleroma.Web.ActivityPub.Transmogrifier
 
   def render("object.json", %{object: %Object{} = object}) do
-    base = Pleroma.Web.ActivityPub.Utils.make_json_ld_header()
+    base = Pleroma.Web.ActivityPub.Utils.make_json_ld_header(object.data)
 
     additional = Transmogrifier.prepare_object(object.data)
     Map.merge(base, additional)
@@ -17,7 +17,7 @@ defmodule Pleroma.Web.ActivityPub.ObjectView do
 
   def render("object.json", %{object: %Activity{data: %{"type" => activity_type}} = activity})
       when activity_type in ["Create", "Listen"] do
-    base = Pleroma.Web.ActivityPub.Utils.make_json_ld_header()
+    base = Pleroma.Web.ActivityPub.Utils.make_json_ld_header(activity.data)
     object = Object.normalize(activity, fetch: false)
 
     additional =
@@ -28,7 +28,7 @@ defmodule Pleroma.Web.ActivityPub.ObjectView do
   end
 
   def render("object.json", %{object: %Activity{} = activity}) do
-    base = Pleroma.Web.ActivityPub.Utils.make_json_ld_header()
+    base = Pleroma.Web.ActivityPub.Utils.make_json_ld_header(activity.data)
     object_id = Object.normalize(activity, id_only: true)
 
     additional =

lib/pleroma/web/common_api/activity_draft.ex

@@ -11,6 +11,9 @@ defmodule Pleroma.Web.CommonAPI.ActivityDraft do
   alias Pleroma.Web.CommonAPI
   alias Pleroma.Web.CommonAPI.Utils
 
+  import Pleroma.EctoType.ActivityPub.ObjectValidators.LanguageCode,
+    only: [good_locale_code?: 1]
+
   import Pleroma.Web.Gettext
   import Pleroma.Web.Utils.Guards, only: [not_empty_string: 1]
 
@@ -38,6 +41,7 @@ defmodule Pleroma.Web.CommonAPI.ActivityDraft do
             cc: [],
             context: nil,
             sensitive: false,
+            language: nil,
             object: nil,
             preview?: false,
             changes: %{}
@@ -64,6 +68,7 @@ defmodule Pleroma.Web.CommonAPI.ActivityDraft do
     |> content()
     |> with_valid(&to_and_cc/1)
     |> with_valid(&context/1)
+    |> with_valid(&language/1)
     |> sensitive()
     |> with_valid(&object/1)
     |> preview?()
@@ -249,6 +254,16 @@ defmodule Pleroma.Web.CommonAPI.ActivityDraft do
     %__MODULE__{draft | sensitive: sensitive}
   end
 
+  defp language(draft) do
+    language = draft.params[:language]
+
+    if good_locale_code?(language) do
+      %__MODULE__{draft | language: language}
+    else
+      draft
+    end
+  end
+
   defp object(draft) do
     emoji = Map.merge(Pleroma.Emoji.Formatter.get_emoji_map(draft.full_payload), draft.emoji)
 
@@ -288,6 +303,7 @@ defmodule Pleroma.Web.CommonAPI.ActivityDraft do
         "mediaType" => Utils.get_content_type(draft.params[:content_type])
       })
       |> Map.put("generator", draft.params[:generator])
+      |> Map.put("language", draft.language)
 
     %__MODULE__{draft | object: object}
   end

lib/pleroma/web/mastodon_api/views/status_view.ex

@@ -227,7 +227,7 @@ defmodule Pleroma.Web.MastodonAPI.StatusView do
       mentions: mentions,
       tags: reblogged[:tags] || [],
       application: build_application(object.data["generator"]),
-      language: nil,
+      language: get_language(object),
       emojis: [],
       pleroma: %{
         local: activity.local,
@@ -445,7 +445,7 @@ defmodule Pleroma.Web.MastodonAPI.StatusView do
       mentions: mentions,
       tags: build_tags(tags),
       application: build_application(object.data["generator"]),
-      language: nil,
+      language: get_language(object),
       emojis: build_emojis(object.data["emoji"]),
       pleroma: %{
         local: activity.local,
@@ -829,6 +829,10 @@ defmodule Pleroma.Web.MastodonAPI.StatusView do
     Utils.get_content_type(nil)
   end
 
+  defp get_language(%{data: %{"language" => "und"}}), do: nil
+
+  defp get_language(object), do: object.data["language"]
+
   defp proxied_url(url, page_url_data) do
     if is_binary(url) do
       build_image_url(URI.parse(url), page_url_data) |> MediaProxy.url()

test/pleroma/ecto_type/activity_pub/object_validators/content_language_map_test.exs

@@ -0,0 +1,56 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2023 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.EctoType.ActivityPub.ObjectValidators.ContentLanguageMapTest do
+  use Pleroma.DataCase, async: true
+
+  alias Pleroma.EctoType.ActivityPub.ObjectValidators.ContentLanguageMap
+
+  test "it validates" do
+    data = %{
+      "en-US" => "mew mew",
+      "en-GB" => "meow meow"
+    }
+
+    assert {:ok, ^data} = ContentLanguageMap.cast(data)
+  end
+
+  test "it validates empty strings" do
+    data = %{
+      "en-US" => "mew mew",
+      "en-GB" => ""
+    }
+
+    assert {:ok, ^data} = ContentLanguageMap.cast(data)
+  end
+
+  test "it ignores non-strings within the map" do
+    data = %{
+      "en-US" => "mew mew",
+      "en-GB" => 123
+    }
+
+    assert {:ok, validated_data} = ContentLanguageMap.cast(data)
+
+    assert validated_data == %{"en-US" => "mew mew"}
+  end
+
+  test "it ignores bad locale codes" do
+    data = %{
+      "en-US" => "mew mew",
+      "en_GB" => "meow meow",
+      "en<<#@!$#!@%!GB" => "meow meow"
+    }
+
+    assert {:ok, validated_data} = ContentLanguageMap.cast(data)
+
+    assert validated_data == %{"en-US" => "mew mew"}
+  end
+
+  test "it complains with non-map data" do
+    assert :error = ContentLanguageMap.cast("mew")
+    assert :error = ContentLanguageMap.cast(["mew"])
+    assert :error = ContentLanguageMap.cast([%{"en-US" => "mew"}])
+  end
+end

test/pleroma/ecto_type/activity_pub/object_validators/language_code_test.exs

@@ -0,0 +1,29 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2023 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.EctoType.ActivityPub.ObjectValidators.LanguageCodeTest do
+  use Pleroma.DataCase, async: true
+
+  alias Pleroma.EctoType.ActivityPub.ObjectValidators.LanguageCode
+
+  test "it accepts language code" do
+    text = "pl"
+    assert {:ok, ^text} = LanguageCode.cast(text)
+  end
+
+  test "it accepts language code with region" do
+    text = "pl-PL"
+    assert {:ok, ^text} = LanguageCode.cast(text)
+  end
+
+  test "errors for invalid language code" do
+    assert {:error, :invalid_language} = LanguageCode.cast("ru_RU")
+    assert {:error, :invalid_language} = LanguageCode.cast(" ")
+    assert {:error, :invalid_language} = LanguageCode.cast("en-US\n")
+  end
+
+  test "errors for non-text" do
+    assert :error == LanguageCode.cast(42)
+  end
+end

test/pleroma/web/activity_pub/object_validators/article_note_page_validator_test.exs

@@ -187,4 +187,71 @@ defmodule Pleroma.Web.ActivityPub.ObjectValidators.ArticleNotePageValidatorTest
              name: "RE: https://server.example/objects/123"
            }
   end
+
+  describe "Note language" do
+    test "it detects language from JSON-LD context" do
+      user = insert(:user)
+
+      note_activity = %{
+        "@context" => ["https://www.w3.org/ns/activitystreams", %{"@language" => "pl"}],
+        "to" => ["https://www.w3.org/ns/activitystreams#Public"],
+        "cc" => [],
+        "type" => "Create",
+        "object" => %{
+          "to" => ["https://www.w3.org/ns/activitystreams#Public"],
+          "cc" => [],
+          "id" => Utils.generate_object_id(),
+          "type" => "Note",
+          "content" => "Szczęść Boże",
+          "attributedTo" => user.ap_id
+        },
+        "actor" => user.ap_id
+      }
+
+      {:ok, _create_activity, meta} = ObjectValidator.validate(note_activity, [])
+
+      assert meta[:object_data]["language"] == "pl"
+    end
+
+    test "it detects language from contentMap" do
+      user = insert(:user)
+
+      note = %{
+        "to" => ["https://www.w3.org/ns/activitystreams#Public"],
+        "cc" => [],
+        "id" => Utils.generate_object_id(),
+        "type" => "Note",
+        "content" => "Szczęść Boże",
+        "contentMap" => %{
+          "de" => "Gott segne",
+          "pl" => "Szczęść Boże"
+        },
+        "attributedTo" => user.ap_id
+      }
+
+      {:ok, object} = ArticleNotePageValidator.cast_and_apply(note)
+
+      assert object.language == "pl"
+    end
+
+    test "it adds contentMap if language is specified" do
+      user = insert(:user)
+
+      note = %{
+        "to" => ["https://www.w3.org/ns/activitystreams#Public"],
+        "cc" => [],
+        "id" => Utils.generate_object_id(),
+        "type" => "Note",
+        "content" => "тест",
+        "language" => "uk",
+        "attributedTo" => user.ap_id
+      }
+
+      {:ok, object} = ArticleNotePageValidator.cast_and_apply(note)
+
+      assert object.contentMap == %{
+               "uk" => "тест"
+             }
+    end
+  end
 end

test/pleroma/web/activity_pub/transmogrifier/note_handling_test.exs

@@ -219,6 +219,36 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier.NoteHandlingTest do
                "<p><span class=\"h-card\"><a href=\"http://localtesting.pleroma.lol/users/lain\" class=\"u-url mention\">@<span>lain</span></a></span></p>"
     end
 
+    test "it only uses contentMap if content is not present" do
+      user = insert(:user)
+
+      message = %{
+        "@context" => "https://www.w3.org/ns/activitystreams",
+        "to" => ["https://www.w3.org/ns/activitystreams#Public"],
+        "cc" => [],
+        "type" => "Create",
+        "object" => %{
+          "to" => ["https://www.w3.org/ns/activitystreams#Public"],
+          "cc" => [],
+          "id" => Utils.generate_object_id(),
+          "type" => "Note",
+          "content" => "Hi",
+          "contentMap" => %{
+            "de" => "Hallo",
+            "uk" => "Привіт"
+          },
+          "inReplyTo" => nil,
+          "attributedTo" => user.ap_id
+        },
+        "actor" => user.ap_id
+      }
+
+      {:ok, %Activity{data: data, local: false}} = Transmogrifier.handle_incoming(message)
+      object = Object.normalize(data["object"], fetch: false)
+
+      assert object.data["content"] == "Hi"
+    end
+
     test "it works for incoming notices with a nil contentMap (firefish)" do
       data =
         File.read!("test/fixtures/mastodon-post-activity-contentmap.json")

test/pleroma/web/activity_pub/transmogrifier_test.exs

@@ -384,6 +384,24 @@ defmodule Pleroma.Web.ActivityPub.TransmogrifierTest do
       assert modified["object"]["quoteUrl"] == quote_id
       assert modified["object"]["quoteUri"] == quote_id
     end
+
+    test "it adds language of the object to its json-ld context" do
+      user = insert(:user)
+
+      {:ok, activity} = CommonAPI.post(user, %{status: "Cześć", language: "pl"})
+      {:ok, modified} = Transmogrifier.prepare_outgoing(activity.object.data)
+
+      assert [_, _, %{"@language" => "pl"}] = modified["@context"]
+    end
+
+    test "it adds language of the object to Create activity json-ld context" do
+      user = insert(:user)
+
+      {:ok, activity} = CommonAPI.post(user, %{status: "Cześć", language: "pl"})
+      {:ok, modified} = Transmogrifier.prepare_outgoing(activity.data)
+
+      assert [_, _, %{"@language" => "pl"}] = modified["@context"]
+    end
   end
 
   describe "actor rewriting" do
@@ -621,5 +639,14 @@ defmodule Pleroma.Web.ActivityPub.TransmogrifierTest do
       processed = Transmogrifier.prepare_object(original)
       assert processed["formerRepresentations"] == original["formerRepresentations"]
     end
+
+    test "it uses contentMap to specify post language" do
+      user = insert(:user)
+
+      {:ok, activity} = CommonAPI.post(user, %{status: "Cześć", language: "pl"})
+      object = Transmogrifier.prepare_object(activity.object.data)
+
+      assert %{"contentMap" => %{"pl" => "Cześć"}} = object
+    end
   end
 end

test/pleroma/web/activity_pub/utils_test.exs

@@ -173,16 +173,30 @@ defmodule Pleroma.Web.ActivityPub.UtilsTest do
     end
   end
 
-  test "make_json_ld_header/0" do
+  describe "make_json_ld_header/1" do
-    assert Utils.make_json_ld_header() == %{
+    test "makes jsonld header" do
-             "@context" => [
+      assert Utils.make_json_ld_header() == %{
-               "https://www.w3.org/ns/activitystreams",
+               "@context" => [
-               "http://localhost:4001/schemas/litepub-0.1.jsonld",
+                 "https://www.w3.org/ns/activitystreams",
-               %{
+                 "http://localhost:4001/schemas/litepub-0.1.jsonld",
-                 "@language" => "und"
+                 %{
-               }
+                   "@language" => "und"
-             ]
+                 }
-           }
+               ]
+             }
+    end
+
+    test "includes language if specified" do
+      assert Utils.make_json_ld_header(%{"language" => "pl"}) == %{
+               "@context" => [
+                 "https://www.w3.org/ns/activitystreams",
+                 "http://localhost:4001/schemas/litepub-0.1.jsonld",
+                 %{
+                   "@language" => "pl"
+                 }
+               ]
+             }
+    end
   end
 
   describe "get_existing_votes" do

test/pleroma/web/mastodon_api/views/status_view_test.exs

@@ -951,6 +951,26 @@ defmodule Pleroma.Web.MastodonAPI.StatusViewTest do
     assert status.edited_at
   end
 
+  test "it shows post language" do
+    user = insert(:user)
+
+    {:ok, post} = CommonAPI.post(user, %{status: "Szczęść Boże", language: "pl"})
+
+    status = StatusView.render("show.json", activity: post)
+
+    assert status.language == "pl"
+  end
+
+  test "doesn't show post language if it's 'und'" do
+    user = insert(:user)
+
+    {:ok, post} = CommonAPI.post(user, %{status: "sdifjogijodfg", language: "und"})
+
+    status = StatusView.render("show.json", activity: post)
+
+    assert status.language == nil
+  end
+
   test "with a source object" do
     note =
       insert(:note,