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   1 # Pleroma: A lightweight social networking server
   2 # Copyright © 2017-2019 Pleroma Authors <https://pleroma.social/>
   3 # SPDX-License-Identifier: AGPL-3.0-only
   4
   5 defmodule Pleroma.Web.ActivityPub.Transmogrifier do
   6   @moduledoc """
   7   A module to handle coding from internal to wire ActivityPub and back.
   8   """
   9   alias Pleroma.User
  10   alias Pleroma.Object
  11   alias Pleroma.Activity
  12   alias Pleroma.Repo
  13   alias Pleroma.Web.ActivityPub.ActivityPub
  14   alias Pleroma.Web.ActivityPub.Utils
  15
  16   import Ecto.Query
  17
  18   require Logger
  19
  20   def get_actor(%{"actor" => actor}) when is_binary(actor) do
  21     actor
  22   end
  23
  24   def get_actor(%{"actor" => actor}) when is_list(actor) do
  25     if is_binary(Enum.at(actor, 0)) do
  26       Enum.at(actor, 0)
  27     else
  28       Enum.find(actor, fn %{"type" => type} -> type in ["Person", "Service", "Application"] end)
  29       |> Map.get("id")
  30     end
  31   end
  32
  33   def get_actor(%{"actor" => %{"id" => id}}) when is_bitstring(id) do
  34     id
  35   end
  36
  37   def get_actor(%{"actor" => nil, "attributedTo" => actor}) when not is_nil(actor) do
  38     get_actor(%{"actor" => actor})
  39   end
  40
  41   @doc """
  42   Checks that an imported AP object's actor matches the domain it came from.
  43   """
  44   def contain_origin(_id, %{"actor" => nil}), do: :error
  45
  46   def contain_origin(id, %{"actor" => _actor} = params) do
  47     id_uri = URI.parse(id)
  48     actor_uri = URI.parse(get_actor(params))
  49
  50     if id_uri.host == actor_uri.host do
  51       :ok
  52     else
  53       :error
  54     end
  55   end
  56
  57   def contain_origin_from_id(_id, %{"id" => nil}), do: :error
  58
  59   def contain_origin_from_id(id, %{"id" => other_id} = _params) do
  60     id_uri = URI.parse(id)
  61     other_uri = URI.parse(other_id)
  62
  63     if id_uri.host == other_uri.host do
  64       :ok
  65     else
  66       :error
  67     end
  68   end
  69
  70   @doc """
  71   Modifies an incoming AP object (mastodon format) to our internal format.
  72   """
  73   def fix_object(object) do
  74     object
  75     |> fix_actor
  76     |> fix_url
  77     |> fix_attachments
  78     |> fix_context
  79     |> fix_in_reply_to
  80     |> fix_emoji
  81     |> fix_tag
  82     |> fix_content_map
  83     |> fix_likes
  84     |> fix_addressing
  85   end
  86
  87   def fix_addressing_list(map, field) do
  88     if is_binary(map[field]) do
  89       map
  90       |> Map.put(field, [map[field]])
  91     else
  92       map
  93     end
  94   end
  95
  96   def fix_explicit_addressing(%{"to" => to, "cc" => cc} = object, explicit_mentions) do
  97     explicit_to =
  98       to
  99       |> Enum.filter(fn x -> x in explicit_mentions end)
 100
 101     explicit_cc =
 102       to
 103       |> Enum.filter(fn x -> x not in explicit_mentions end)
 104
 105     final_cc =
 106       (cc ++ explicit_cc)
 107       |> Enum.uniq()
 108
 109     object
 110     |> Map.put("to", explicit_to)
 111     |> Map.put("cc", final_cc)
 112   end
 113
 114   def fix_explicit_addressing(object, _explicit_mentions), do: object
 115
 116   # if directMessage flag is set to true, leave the addressing alone
 117   def fix_explicit_addressing(%{"directMessage" => true} = object), do: object
 118
 119   def fix_explicit_addressing(object) do
 120     explicit_mentions =
 121       object
 122       |> Utils.determine_explicit_mentions()
 123
 124     explicit_mentions = explicit_mentions ++ ["https://www.w3.org/ns/activitystreams#Public"]
 125
 126     object
 127     |> fix_explicit_addressing(explicit_mentions)
 128   end
 129
 130   def fix_addressing(object) do
 131     object
 132     |> fix_addressing_list("to")
 133     |> fix_addressing_list("cc")
 134     |> fix_addressing_list("bto")
 135     |> fix_addressing_list("bcc")
 136     |> fix_explicit_addressing
 137   end
 138
 139   def fix_actor(%{"attributedTo" => actor} = object) do
 140     object
 141     |> Map.put("actor", get_actor(%{"actor" => actor}))
 142   end
 143
 144   # Check for standardisation
 145   # This is what Peertube does
 146   # curl -H 'Accept: application/activity+json' $likes | jq .totalItems
 147   # Prismo returns only an integer (count) as "likes"
 148   def fix_likes(%{"likes" => likes} = object) when not is_map(likes) do
 149     object
 150     |> Map.put("likes", [])
 151     |> Map.put("like_count", 0)
 152   end
 153
 154   def fix_likes(object) do
 155     object
 156   end
 157
 158   def fix_in_reply_to(%{"inReplyTo" => in_reply_to} = object)
 159       when not is_nil(in_reply_to) do
 160     in_reply_to_id =
 161       cond do
 162         is_bitstring(in_reply_to) ->
 163           in_reply_to
 164
 165         is_map(in_reply_to) && is_bitstring(in_reply_to["id"]) ->
 166           in_reply_to["id"]
 167
 168         is_list(in_reply_to) && is_bitstring(Enum.at(in_reply_to, 0)) ->
 169           Enum.at(in_reply_to, 0)
 170
 171         # Maybe I should output an error too?
 172         true ->
 173           ""
 174       end
 175
 176     case fetch_obj_helper(in_reply_to_id) do
 177       {:ok, replied_object} ->
 178         with %Activity{} = activity <-
 179                Activity.get_create_by_object_ap_id(replied_object.data["id"]) do
 180           object
 181           |> Map.put("inReplyTo", replied_object.data["id"])
 182           |> Map.put("inReplyToAtomUri", object["inReplyToAtomUri"] || in_reply_to_id)
 183           |> Map.put("inReplyToStatusId", activity.id)
 184           |> Map.put("conversation", replied_object.data["context"] || object["conversation"])
 185           |> Map.put("context", replied_object.data["context"] || object["conversation"])
 186         else
 187           e ->
 188             Logger.error("Couldn't fetch \"#{inspect(in_reply_to_id)}\", error: #{inspect(e)}")
 189             object
 190         end
 191
 192       e ->
 193         Logger.error("Couldn't fetch \"#{inspect(in_reply_to_id)}\", error: #{inspect(e)}")
 194         object
 195     end
 196   end
 197
 198   def fix_in_reply_to(object), do: object
 199
 200   def fix_context(object) do
 201     context = object["context"] || object["conversation"] || Utils.generate_context_id()
 202
 203     object
 204     |> Map.put("context", context)
 205     |> Map.put("conversation", context)
 206   end
 207
 208   def fix_attachments(%{"attachment" => attachment} = object) when is_list(attachment) do
 209     attachments =
 210       attachment
 211       |> Enum.map(fn data ->
 212         media_type = data["mediaType"] || data["mimeType"]
 213         href = data["url"] || data["href"]
 214
 215         url = [%{"type" => "Link", "mediaType" => media_type, "href" => href}]
 216
 217         data
 218         |> Map.put("mediaType", media_type)
 219         |> Map.put("url", url)
 220       end)
 221
 222     object
 223     |> Map.put("attachment", attachments)
 224   end
 225
 226   def fix_attachments(%{"attachment" => attachment} = object) when is_map(attachment) do
 227     Map.put(object, "attachment", [attachment])
 228     |> fix_attachments()
 229   end
 230
 231   def fix_attachments(object), do: object
 232
 233   def fix_url(%{"url" => url} = object) when is_map(url) do
 234     object
 235     |> Map.put("url", url["href"])
 236   end
 237
 238   def fix_url(%{"type" => "Video", "url" => url} = object) when is_list(url) do
 239     first_element = Enum.at(url, 0)
 240
 241     link_element =
 242       url
 243       |> Enum.filter(fn x -> is_map(x) end)
 244       |> Enum.filter(fn x -> x["mimeType"] == "text/html" end)
 245       |> Enum.at(0)
 246
 247     object
 248     |> Map.put("attachment", [first_element])
 249     |> Map.put("url", link_element["href"])
 250   end
 251
 252   def fix_url(%{"type" => object_type, "url" => url} = object)
 253       when object_type != "Video" and is_list(url) do
 254     first_element = Enum.at(url, 0)
 255
 256     url_string =
 257       cond do
 258         is_bitstring(first_element) -> first_element
 259         is_map(first_element) -> first_element["href"] || ""
 260         true -> ""
 261       end
 262
 263     object
 264     |> Map.put("url", url_string)
 265   end
 266
 267   def fix_url(object), do: object
 268
 269   def fix_emoji(%{"tag" => tags} = object) when is_list(tags) do
 270     emoji = tags |> Enum.filter(fn data -> data["type"] == "Emoji" and data["icon"] end)
 271
 272     emoji =
 273       emoji
 274       |> Enum.reduce(%{}, fn data, mapping ->
 275         name = String.trim(data["name"], ":")
 276
 277         mapping |> Map.put(name, data["icon"]["url"])
 278       end)
 279
 280     # we merge mastodon and pleroma emoji into a single mapping, to allow for both wire formats
 281     emoji = Map.merge(object["emoji"] || %{}, emoji)
 282
 283     object
 284     |> Map.put("emoji", emoji)
 285   end
 286
 287   def fix_emoji(%{"tag" => %{"type" => "Emoji"} = tag} = object) do
 288     name = String.trim(tag["name"], ":")
 289     emoji = %{name => tag["icon"]["url"]}
 290
 291     object
 292     |> Map.put("emoji", emoji)
 293   end
 294
 295   def fix_emoji(object), do: object
 296
 297   def fix_tag(%{"tag" => tag} = object) when is_list(tag) do
 298     tags =
 299       tag
 300       |> Enum.filter(fn data -> data["type"] == "Hashtag" and data["name"] end)
 301       |> Enum.map(fn data -> String.slice(data["name"], 1..-1) end)
 302
 303     combined = tag ++ tags
 304
 305     object
 306     |> Map.put("tag", combined)
 307   end
 308
 309   def fix_tag(%{"tag" => %{"type" => "Hashtag", "name" => hashtag} = tag} = object) do
 310     combined = [tag, String.slice(hashtag, 1..-1)]
 311
 312     object
 313     |> Map.put("tag", combined)
 314   end
 315
 316   def fix_tag(object), do: object
 317
 318   # content map usually only has one language so this will do for now.
 319   def fix_content_map(%{"contentMap" => content_map} = object) do
 320     content_groups = Map.to_list(content_map)
 321     {_, content} = Enum.at(content_groups, 0)
 322
 323     object
 324     |> Map.put("content", content)
 325   end
 326
 327   def fix_content_map(object), do: object
 328
 329   defp mastodon_follow_hack(%{"id" => id, "actor" => follower_id}, followed) do
 330     with true <- id =~ "follows",
 331          %User{local: true} = follower <- User.get_cached_by_ap_id(follower_id),
 332          %Activity{} = activity <- Utils.fetch_latest_follow(follower, followed) do
 333       {:ok, activity}
 334     else
 335       _ -> {:error, nil}
 336     end
 337   end
 338
 339   defp mastodon_follow_hack(_, _), do: {:error, nil}
 340
 341   defp get_follow_activity(follow_object, followed) do
 342     with object_id when not is_nil(object_id) <- Utils.get_ap_id(follow_object),
 343          {_, %Activity{} = activity} <- {:activity, Activity.get_by_ap_id(object_id)} do
 344       {:ok, activity}
 345     else
 346       # Can't find the activity. This might a Mastodon 2.3 "Accept"
 347       {:activity, nil} ->
 348         mastodon_follow_hack(follow_object, followed)
 349
 350       _ ->
 351         {:error, nil}
 352     end
 353   end
 354
 355   # disallow objects with bogus IDs
 356   def handle_incoming(%{"id" => nil}), do: :error
 357   def handle_incoming(%{"id" => ""}), do: :error
 358   # length of https:// = 8, should validate better, but good enough for now.
 359   def handle_incoming(%{"id" => id}) when not (is_binary(id) and length(id) > 8), do: :error
 360
 361   # TODO: validate those with a Ecto scheme
 362   # - tags
 363   # - emoji
 364   def handle_incoming(%{"type" => "Create", "object" => %{"type" => objtype} = object} = data)
 365       when objtype in ["Article", "Note", "Video", "Page"] do
 366     actor = get_actor(data)
 367
 368     data =
 369       Map.put(data, "actor", actor)
 370       |> fix_addressing
 371
 372     with nil <- Activity.get_create_by_object_ap_id(object["id"]),
 373          %User{} = user <- User.get_or_fetch_by_ap_id(data["actor"]) do
 374       object = fix_object(data["object"])
 375
 376       params = %{
 377         to: data["to"],
 378         object: object,
 379         actor: user,
 380         context: object["conversation"],
 381         local: false,
 382         published: data["published"],
 383         additional:
 384           Map.take(data, [
 385             "cc",
 386             "directMessage",
 387             "id"
 388           ])
 389       }
 390
 391       ActivityPub.create(params)
 392     else
 393       %Activity{} = activity -> {:ok, activity}
 394       _e -> :error
 395     end
 396   end
 397
 398   def handle_incoming(
 399         %{"type" => "Follow", "object" => followed, "actor" => follower, "id" => id} = data
 400       ) do
 401     with %User{local: true} = followed <- User.get_cached_by_ap_id(followed),
 402          %User{} = follower <- User.get_or_fetch_by_ap_id(follower),
 403          {:ok, activity} <- ActivityPub.follow(follower, followed, id, false) do
 404       if not User.locked?(followed) do
 405         ActivityPub.accept(%{
 406           to: [follower.ap_id],
 407           actor: followed.ap_id,
 408           object: data,
 409           local: true
 410         })
 411
 412         User.follow(follower, followed)
 413       end
 414
 415       {:ok, activity}
 416     else
 417       _e -> :error
 418     end
 419   end
 420
 421   def handle_incoming(
 422         %{"type" => "Accept", "object" => follow_object, "actor" => _actor, "id" => _id} = data
 423       ) do
 424     with actor <- get_actor(data),
 425          %User{} = followed <- User.get_or_fetch_by_ap_id(actor),
 426          {:ok, follow_activity} <- get_follow_activity(follow_object, followed),
 427          {:ok, follow_activity} <- Utils.update_follow_state(follow_activity, "accept"),
 428          %User{local: true} = follower <- User.get_cached_by_ap_id(follow_activity.data["actor"]),
 429          {:ok, activity} <-
 430            ActivityPub.accept(%{
 431              to: follow_activity.data["to"],
 432              type: "Accept",
 433              actor: followed.ap_id,
 434              object: follow_activity.data["id"],
 435              local: false
 436            }) do
 437       if not User.following?(follower, followed) do
 438         {:ok, _follower} = User.follow(follower, followed)
 439       end
 440
 441       {:ok, activity}
 442     else
 443       _e -> :error
 444     end
 445   end
 446
 447   def handle_incoming(
 448         %{"type" => "Reject", "object" => follow_object, "actor" => _actor, "id" => _id} = data
 449       ) do
 450     with actor <- get_actor(data),
 451          %User{} = followed <- User.get_or_fetch_by_ap_id(actor),
 452          {:ok, follow_activity} <- get_follow_activity(follow_object, followed),
 453          {:ok, follow_activity} <- Utils.update_follow_state(follow_activity, "reject"),
 454          %User{local: true} = follower <- User.get_cached_by_ap_id(follow_activity.data["actor"]),
 455          {:ok, activity} <-
 456            ActivityPub.accept(%{
 457              to: follow_activity.data["to"],
 458              type: "Accept",
 459              actor: followed.ap_id,
 460              object: follow_activity.data["id"],
 461              local: false
 462            }) do
 463       User.unfollow(follower, followed)
 464
 465       {:ok, activity}
 466     else
 467       _e -> :error
 468     end
 469   end
 470
 471   def handle_incoming(
 472         %{"type" => "Like", "object" => object_id, "actor" => _actor, "id" => id} = data
 473       ) do
 474     with actor <- get_actor(data),
 475          %User{} = actor <- User.get_or_fetch_by_ap_id(actor),
 476          {:ok, object} <- get_obj_helper(object_id) || fetch_obj_helper(object_id),
 477          {:ok, activity, _object} <- ActivityPub.like(actor, object, id, false) do
 478       {:ok, activity}
 479     else
 480       _e -> :error
 481     end
 482   end
 483
 484   def handle_incoming(
 485         %{"type" => "Announce", "object" => object_id, "actor" => _actor, "id" => id} = data
 486       ) do
 487     with actor <- get_actor(data),
 488          %User{} = actor <- User.get_or_fetch_by_ap_id(actor),
 489          {:ok, object} <- get_obj_helper(object_id) || fetch_obj_helper(object_id),
 490          public <- ActivityPub.is_public?(data),
 491          {:ok, activity, _object} <- ActivityPub.announce(actor, object, id, false, public) do
 492       {:ok, activity}
 493     else
 494       _e -> :error
 495     end
 496   end
 497
 498   def handle_incoming(
 499         %{"type" => "Update", "object" => %{"type" => object_type} = object, "actor" => actor_id} =
 500           data
 501       )
 502       when object_type in ["Person", "Application", "Service", "Organization"] do
 503     with %User{ap_id: ^actor_id} = actor <- User.get_by_ap_id(object["id"]) do
 504       {:ok, new_user_data} = ActivityPub.user_data_from_user_object(object)
 505
 506       banner = new_user_data[:info]["banner"]
 507       locked = new_user_data[:info]["locked"] || false
 508
 509       update_data =
 510         new_user_data
 511         |> Map.take([:name, :bio, :avatar])
 512         |> Map.put(:info, %{"banner" => banner, "locked" => locked})
 513
 514       actor
 515       |> User.upgrade_changeset(update_data)
 516       |> User.update_and_set_cache()
 517
 518       ActivityPub.update(%{
 519         local: false,
 520         to: data["to"] || [],
 521         cc: data["cc"] || [],
 522         object: object,
 523         actor: actor_id
 524       })
 525     else
 526       e ->
 527         Logger.error(e)
 528         :error
 529     end
 530   end
 531
 532   # TODO: We presently assume that any actor on the same origin domain as the object being
 533   # deleted has the rights to delete that object.  A better way to validate whether or not
 534   # the object should be deleted is to refetch the object URI, which should return either
 535   # an error or a tombstone.  This would allow us to verify that a deletion actually took
 536   # place.
 537   def handle_incoming(
 538         %{"type" => "Delete", "object" => object_id, "actor" => _actor, "id" => _id} = data
 539       ) do
 540     object_id = Utils.get_ap_id(object_id)
 541
 542     with actor <- get_actor(data),
 543          %User{} = actor <- User.get_or_fetch_by_ap_id(actor),
 544          {:ok, object} <- get_obj_helper(object_id) || fetch_obj_helper(object_id),
 545          :ok <- contain_origin(actor.ap_id, object.data),
 546          {:ok, activity} <- ActivityPub.delete(object, false) do
 547       {:ok, activity}
 548     else
 549       _e -> :error
 550     end
 551   end
 552
 553   def handle_incoming(
 554         %{
 555           "type" => "Undo",
 556           "object" => %{"type" => "Announce", "object" => object_id},
 557           "actor" => _actor,
 558           "id" => id
 559         } = data
 560       ) do
 561     with actor <- get_actor(data),
 562          %User{} = actor <- User.get_or_fetch_by_ap_id(actor),
 563          {:ok, object} <- get_obj_helper(object_id) || fetch_obj_helper(object_id),
 564          {:ok, activity, _} <- ActivityPub.unannounce(actor, object, id, false) do
 565       {:ok, activity}
 566     else
 567       _e -> :error
 568     end
 569   end
 570
 571   def handle_incoming(
 572         %{
 573           "type" => "Undo",
 574           "object" => %{"type" => "Follow", "object" => followed},
 575           "actor" => follower,
 576           "id" => id
 577         } = _data
 578       ) do
 579     with %User{local: true} = followed <- User.get_cached_by_ap_id(followed),
 580          %User{} = follower <- User.get_or_fetch_by_ap_id(follower),
 581          {:ok, activity} <- ActivityPub.unfollow(follower, followed, id, false) do
 582       User.unfollow(follower, followed)
 583       {:ok, activity}
 584     else
 585       _e -> :error
 586     end
 587   end
 588
 589   def handle_incoming(
 590         %{
 591           "type" => "Undo",
 592           "object" => %{"type" => "Block", "object" => blocked},
 593           "actor" => blocker,
 594           "id" => id
 595         } = _data
 596       ) do
 597     with true <- Pleroma.Config.get([:activitypub, :accept_blocks]),
 598          %User{local: true} = blocked <- User.get_cached_by_ap_id(blocked),
 599          %User{} = blocker <- User.get_or_fetch_by_ap_id(blocker),
 600          {:ok, activity} <- ActivityPub.unblock(blocker, blocked, id, false) do
 601       User.unblock(blocker, blocked)
 602       {:ok, activity}
 603     else
 604       _e -> :error
 605     end
 606   end
 607
 608   def handle_incoming(
 609         %{"type" => "Block", "object" => blocked, "actor" => blocker, "id" => id} = _data
 610       ) do
 611     with true <- Pleroma.Config.get([:activitypub, :accept_blocks]),
 612          %User{local: true} = blocked = User.get_cached_by_ap_id(blocked),
 613          %User{} = blocker = User.get_or_fetch_by_ap_id(blocker),
 614          {:ok, activity} <- ActivityPub.block(blocker, blocked, id, false) do
 615       User.unfollow(blocker, blocked)
 616       User.block(blocker, blocked)
 617       {:ok, activity}
 618     else
 619       _e -> :error
 620     end
 621   end
 622
 623   def handle_incoming(
 624         %{
 625           "type" => "Undo",
 626           "object" => %{"type" => "Like", "object" => object_id},
 627           "actor" => _actor,
 628           "id" => id
 629         } = data
 630       ) do
 631     with actor <- get_actor(data),
 632          %User{} = actor <- User.get_or_fetch_by_ap_id(actor),
 633          {:ok, object} <- get_obj_helper(object_id) || fetch_obj_helper(object_id),
 634          {:ok, activity, _, _} <- ActivityPub.unlike(actor, object, id, false) do
 635       {:ok, activity}
 636     else
 637       _e -> :error
 638     end
 639   end
 640
 641   def handle_incoming(_), do: :error
 642
 643   def fetch_obj_helper(id) when is_bitstring(id), do: ActivityPub.fetch_object_from_id(id)
 644   def fetch_obj_helper(obj) when is_map(obj), do: ActivityPub.fetch_object_from_id(obj["id"])
 645
 646   def get_obj_helper(id) do
 647     if object = Object.normalize(id), do: {:ok, object}, else: nil
 648   end
 649
 650   def set_reply_to_uri(%{"inReplyTo" => inReplyTo} = object) do
 651     with false <- String.starts_with?(inReplyTo, "http"),
 652          {:ok, %{data: replied_to_object}} <- get_obj_helper(inReplyTo) do
 653       Map.put(object, "inReplyTo", replied_to_object["external_url"] || inReplyTo)
 654     else
 655       _e -> object
 656     end
 657   end
 658
 659   def set_reply_to_uri(obj), do: obj
 660
 661   # Prepares the object of an outgoing create activity.
 662   def prepare_object(object) do
 663     object
 664     |> set_sensitive
 665     |> add_hashtags
 666     |> add_mention_tags
 667     |> add_emoji_tags
 668     |> add_attributed_to
 669     |> add_likes
 670     |> prepare_attachments
 671     |> set_conversation
 672     |> set_reply_to_uri
 673     |> strip_internal_fields
 674     |> strip_internal_tags
 675   end
 676
 677   #  @doc
 678   #  """
 679   #  internal -> Mastodon
 680   #  """
 681
 682   def prepare_outgoing(%{"type" => "Create", "object" => object} = data) do
 683     object =
 684       object
 685       |> prepare_object
 686
 687     data =
 688       data
 689       |> Map.put("object", object)
 690       |> Map.merge(Utils.make_json_ld_header())
 691
 692     {:ok, data}
 693   end
 694
 695   # Mastodon Accept/Reject requires a non-normalized object containing the actor URIs,
 696   # because of course it does.
 697   def prepare_outgoing(%{"type" => "Accept"} = data) do
 698     with follow_activity <- Activity.normalize(data["object"]) do
 699       object = %{
 700         "actor" => follow_activity.actor,
 701         "object" => follow_activity.data["object"],
 702         "id" => follow_activity.data["id"],
 703         "type" => "Follow"
 704       }
 705
 706       data =
 707         data
 708         |> Map.put("object", object)
 709         |> Map.merge(Utils.make_json_ld_header())
 710
 711       {:ok, data}
 712     end
 713   end
 714
 715   def prepare_outgoing(%{"type" => "Reject"} = data) do
 716     with follow_activity <- Activity.normalize(data["object"]) do
 717       object = %{
 718         "actor" => follow_activity.actor,
 719         "object" => follow_activity.data["object"],
 720         "id" => follow_activity.data["id"],
 721         "type" => "Follow"
 722       }
 723
 724       data =
 725         data
 726         |> Map.put("object", object)
 727         |> Map.merge(Utils.make_json_ld_header())
 728
 729       {:ok, data}
 730     end
 731   end
 732
 733   def prepare_outgoing(%{"type" => _type} = data) do
 734     data =
 735       data
 736       |> maybe_fix_object_url
 737       |> Map.merge(Utils.make_json_ld_header())
 738
 739     {:ok, data}
 740   end
 741
 742   def maybe_fix_object_url(data) do
 743     if is_binary(data["object"]) and not String.starts_with?(data["object"], "http") do
 744       case fetch_obj_helper(data["object"]) do
 745         {:ok, relative_object} ->
 746           if relative_object.data["external_url"] do
 747             _data =
 748               data
 749               |> Map.put("object", relative_object.data["external_url"])
 750           else
 751             data
 752           end
 753
 754         e ->
 755           Logger.error("Couldn't fetch #{data["object"]} #{inspect(e)}")
 756           data
 757       end
 758     else
 759       data
 760     end
 761   end
 762
 763   def add_hashtags(object) do
 764     tags =
 765       (object["tag"] || [])
 766       |> Enum.map(fn tag ->
 767         %{
 768           "href" => Pleroma.Web.Endpoint.url() <> "/tags/#{tag}",
 769           "name" => "##{tag}",
 770           "type" => "Hashtag"
 771         }
 772       end)
 773
 774     object
 775     |> Map.put("tag", tags)
 776   end
 777
 778   def add_mention_tags(object) do
 779     mentions =
 780       object
 781       |> Utils.get_notified_from_object()
 782       |> Enum.map(fn user ->
 783         %{"type" => "Mention", "href" => user.ap_id, "name" => "@#{user.nickname}"}
 784       end)
 785
 786     tags = object["tag"] || []
 787
 788     object
 789     |> Map.put("tag", tags ++ mentions)
 790   end
 791
 792   # TODO: we should probably send mtime instead of unix epoch time for updated
 793   def add_emoji_tags(object) do
 794     tags = object["tag"] || []
 795     emoji = object["emoji"] || []
 796
 797     out =
 798       emoji
 799       |> Enum.map(fn {name, url} ->
 800         %{
 801           "icon" => %{"url" => url, "type" => "Image"},
 802           "name" => ":" <> name <> ":",
 803           "type" => "Emoji",
 804           "updated" => "1970-01-01T00:00:00Z",
 805           "id" => url
 806         }
 807       end)
 808
 809     object
 810     |> Map.put("tag", tags ++ out)
 811   end
 812
 813   def set_conversation(object) do
 814     Map.put(object, "conversation", object["context"])
 815   end
 816
 817   def set_sensitive(object) do
 818     tags = object["tag"] || []
 819     Map.put(object, "sensitive", "nsfw" in tags)
 820   end
 821
 822   def add_attributed_to(object) do
 823     attributedTo = object["attributedTo"] || object["actor"]
 824
 825     object
 826     |> Map.put("attributedTo", attributedTo)
 827   end
 828
 829   def add_likes(%{"id" => id, "like_count" => likes} = object) do
 830     likes = %{
 831       "id" => "#{id}/likes",
 832       "first" => "#{id}/likes?page=1",
 833       "type" => "OrderedCollection",
 834       "totalItems" => likes
 835     }
 836
 837     object
 838     |> Map.put("likes", likes)
 839   end
 840
 841   def add_likes(object) do
 842     object
 843   end
 844
 845   def prepare_attachments(object) do
 846     attachments =
 847       (object["attachment"] || [])
 848       |> Enum.map(fn data ->
 849         [%{"mediaType" => media_type, "href" => href} | _] = data["url"]
 850         %{"url" => href, "mediaType" => media_type, "name" => data["name"], "type" => "Document"}
 851       end)
 852
 853     object
 854     |> Map.put("attachment", attachments)
 855   end
 856
 857   defp strip_internal_fields(object) do
 858     object
 859     |> Map.drop([
 860       "like_count",
 861       "announcements",
 862       "announcement_count",
 863       "emoji",
 864       "context_id"
 865     ])
 866   end
 867
 868   defp strip_internal_tags(%{"tag" => tags} = object) do
 869     tags =
 870       tags
 871       |> Enum.filter(fn x -> is_map(x) end)
 872
 873     object
 874     |> Map.put("tag", tags)
 875   end
 876
 877   defp strip_internal_tags(object), do: object
 878
 879   defp user_upgrade_task(user) do
 880     old_follower_address = User.ap_followers(user)
 881
 882     q =
 883       from(
 884         u in User,
 885         where: ^old_follower_address in u.following,
 886         update: [
 887           set: [
 888             following:
 889               fragment(
 890                 "array_replace(?,?,?)",
 891                 u.following,
 892                 ^old_follower_address,
 893                 ^user.follower_address
 894               )
 895           ]
 896         ]
 897       )
 898
 899     Repo.update_all(q, [])
 900
 901     maybe_retire_websub(user.ap_id)
 902
 903     q =
 904       from(
 905         a in Activity,
 906         where: ^old_follower_address in a.recipients,
 907         update: [
 908           set: [
 909             recipients:
 910               fragment(
 911                 "array_replace(?,?,?)",
 912                 a.recipients,
 913                 ^old_follower_address,
 914                 ^user.follower_address
 915               )
 916           ]
 917         ]
 918       )
 919
 920     Repo.update_all(q, [])
 921   end
 922
 923   def upgrade_user_from_ap_id(ap_id, async \\ true) do
 924     with %User{local: false} = user <- User.get_by_ap_id(ap_id),
 925          {:ok, data} <- ActivityPub.fetch_and_prepare_user_from_ap_id(ap_id) do
 926       already_ap = User.ap_enabled?(user)
 927
 928       {:ok, user} =
 929         User.upgrade_changeset(user, data)
 930         |> Repo.update()
 931
 932       if !already_ap do
 933         # This could potentially take a long time, do it in the background
 934         if async do
 935           Task.start(fn ->
 936             user_upgrade_task(user)
 937           end)
 938         else
 939           user_upgrade_task(user)
 940         end
 941       end
 942
 943       {:ok, user}
 944     else
 945       e -> e
 946     end
 947   end
 948
 949   def maybe_retire_websub(ap_id) do
 950     # some sanity checks
 951     if is_binary(ap_id) && String.length(ap_id) > 8 do
 952       q =
 953         from(
 954           ws in Pleroma.Web.Websub.WebsubClientSubscription,
 955           where: fragment("? like ?", ws.topic, ^"#{ap_id}%")
 956         )
 957
 958       Repo.delete_all(q)
 959     end
 960   end
 961
 962   def maybe_fix_user_url(data) do
 963     if is_map(data["url"]) do
 964       Map.put(data, "url", data["url"]["href"])
 965     else
 966       data
 967     end
 968   end
 969
 970   def maybe_fix_user_object(data) do
 971     data
 972     |> maybe_fix_user_url
 973   end
 974 end