git.squeep.com Git - akkoma/blob - lib/pleroma/web/ostatus/ostatus.ex

   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.OStatus do
   6   @httpoison Application.get_env(:pleroma, :httpoison)
   7
   8   import Ecto.Query
   9   import Pleroma.Web.XML
  10   require Logger
  11
  12   alias Pleroma.{Repo, User, Web, Object, Activity}
  13   alias Pleroma.Web.ActivityPub.ActivityPub
  14   alias Pleroma.Web.{WebFinger, Websub}
  15   alias Pleroma.Web.OStatus.{FollowHandler, UnfollowHandler, NoteHandler, DeleteHandler}
  16   alias Pleroma.Web.ActivityPub.Transmogrifier
  17
  18   def is_representable?(%Activity{data: data}) do
  19     object = Object.normalize(data["object"])
  20
  21     cond do
  22       is_nil(object) ->
  23         false
  24
  25       object.data["type"] == "Note" ->
  26         true
  27
  28       true ->
  29         false
  30     end
  31   end
  32
  33   def feed_path(user) do
  34     "#{user.ap_id}/feed.atom"
  35   end
  36
  37   def pubsub_path(user) do
  38     "#{Web.base_url()}/push/hub/#{user.nickname}"
  39   end
  40
  41   def salmon_path(user) do
  42     "#{user.ap_id}/salmon"
  43   end
  44
  45   def remote_follow_path do
  46     "#{Web.base_url()}/ostatus_subscribe?acct={uri}"
  47   end
  48
  49   def handle_incoming(xml_string) do
  50     with doc when doc != :error <- parse_document(xml_string) do
  51       entries = :xmerl_xpath.string('//entry', doc)
  52
  53       activities =
  54         Enum.map(entries, fn entry ->
  55           {:xmlObj, :string, object_type} =
  56             :xmerl_xpath.string('string(/entry/activity:object-type[1])', entry)
  57
  58           {:xmlObj, :string, verb} = :xmerl_xpath.string('string(/entry/activity:verb[1])', entry)
  59           Logger.debug("Handling #{verb}")
  60
  61           try do
  62             case verb do
  63               'http://activitystrea.ms/schema/1.0/delete' ->
  64                 with {:ok, activity} <- DeleteHandler.handle_delete(entry, doc), do: activity
  65
  66               'http://activitystrea.ms/schema/1.0/follow' ->
  67                 with {:ok, activity} <- FollowHandler.handle(entry, doc), do: activity
  68
  69               'http://activitystrea.ms/schema/1.0/unfollow' ->
  70                 with {:ok, activity} <- UnfollowHandler.handle(entry, doc), do: activity
  71
  72               'http://activitystrea.ms/schema/1.0/share' ->
  73                 with {:ok, activity, retweeted_activity} <- handle_share(entry, doc),
  74                      do: [activity, retweeted_activity]
  75
  76               'http://activitystrea.ms/schema/1.0/favorite' ->
  77                 with {:ok, activity, favorited_activity} <- handle_favorite(entry, doc),
  78                      do: [activity, favorited_activity]
  79
  80               _ ->
  81                 case object_type do
  82                   'http://activitystrea.ms/schema/1.0/note' ->
  83                     with {:ok, activity} <- NoteHandler.handle_note(entry, doc), do: activity
  84
  85                   'http://activitystrea.ms/schema/1.0/comment' ->
  86                     with {:ok, activity} <- NoteHandler.handle_note(entry, doc), do: activity
  87
  88                   _ ->
  89                     Logger.error("Couldn't parse incoming document")
  90                     nil
  91                 end
  92             end
  93           rescue
  94             e ->
  95               Logger.error("Error occured while handling activity")
  96               Logger.error(xml_string)
  97               Logger.error(inspect(e))
  98               nil
  99           end
 100         end)
 101         |> Enum.filter(& &1)
 102
 103       {:ok, activities}
 104     else
 105       _e -> {:error, []}
 106     end
 107   end
 108
 109   def make_share(entry, doc, retweeted_activity) do
 110     with {:ok, actor} <- find_make_or_update_user(doc),
 111          %Object{} = object <- Object.normalize(retweeted_activity.data["object"]),
 112          id when not is_nil(id) <- string_from_xpath("/entry/id", entry),
 113          {:ok, activity, _object} = ActivityPub.announce(actor, object, id, false) do
 114       {:ok, activity}
 115     end
 116   end
 117
 118   def handle_share(entry, doc) do
 119     with {:ok, retweeted_activity} <- get_or_build_object(entry),
 120          {:ok, activity} <- make_share(entry, doc, retweeted_activity) do
 121       {:ok, activity, retweeted_activity}
 122     else
 123       e -> {:error, e}
 124     end
 125   end
 126
 127   def make_favorite(entry, doc, favorited_activity) do
 128     with {:ok, actor} <- find_make_or_update_user(doc),
 129          %Object{} = object <- Object.normalize(favorited_activity.data["object"]),
 130          id when not is_nil(id) <- string_from_xpath("/entry/id", entry),
 131          {:ok, activity, _object} = ActivityPub.like(actor, object, id, false) do
 132       {:ok, activity}
 133     end
 134   end
 135
 136   def get_or_build_object(entry) do
 137     with {:ok, activity} <- get_or_try_fetching(entry) do
 138       {:ok, activity}
 139     else
 140       _e ->
 141         with [object] <- :xmerl_xpath.string('/entry/activity:object', entry) do
 142           NoteHandler.handle_note(object, object)
 143         end
 144     end
 145   end
 146
 147   def get_or_try_fetching(entry) do
 148     Logger.debug("Trying to get entry from db")
 149
 150     with id when not is_nil(id) <- string_from_xpath("//activity:object[1]/id", entry),
 151          %Activity{} = activity <- Activity.get_create_activity_by_object_ap_id(id) do
 152       {:ok, activity}
 153     else
 154       _ ->
 155         Logger.debug("Couldn't get, will try to fetch")
 156
 157         with href when not is_nil(href) <-
 158                string_from_xpath("//activity:object[1]/link[@type=\"text/html\"]/@href", entry),
 159              {:ok, [favorited_activity]} <- fetch_activity_from_url(href) do
 160           {:ok, favorited_activity}
 161         else
 162           e -> Logger.debug("Couldn't find href: #{inspect(e)}")
 163         end
 164     end
 165   end
 166
 167   def handle_favorite(entry, doc) do
 168     with {:ok, favorited_activity} <- get_or_try_fetching(entry),
 169          {:ok, activity} <- make_favorite(entry, doc, favorited_activity) do
 170       {:ok, activity, favorited_activity}
 171     else
 172       e -> {:error, e}
 173     end
 174   end
 175
 176   def get_attachments(entry) do
 177     :xmerl_xpath.string('/entry/link[@rel="enclosure"]', entry)
 178     |> Enum.map(fn enclosure ->
 179       with href when not is_nil(href) <- string_from_xpath("/link/@href", enclosure),
 180            type when not is_nil(type) <- string_from_xpath("/link/@type", enclosure) do
 181         %{
 182           "type" => "Attachment",
 183           "url" => [
 184             %{
 185               "type" => "Link",
 186               "mediaType" => type,
 187               "href" => href
 188             }
 189           ]
 190         }
 191       end
 192     end)
 193     |> Enum.filter(& &1)
 194   end
 195
 196   @doc """
 197     Gets the content from a an entry.
 198   """
 199   def get_content(entry) do
 200     string_from_xpath("//content", entry)
 201   end
 202
 203   @doc """
 204     Get the cw that mastodon uses.
 205   """
 206   def get_cw(entry) do
 207     with cw when not is_nil(cw) <- string_from_xpath("/*/summary", entry) do
 208       cw
 209     else
 210       _e -> nil
 211     end
 212   end
 213
 214   def get_tags(entry) do
 215     :xmerl_xpath.string('//category', entry)
 216     |> Enum.map(fn category -> string_from_xpath("/category/@term", category) end)
 217     |> Enum.filter(& &1)
 218     |> Enum.map(&String.downcase/1)
 219   end
 220
 221   def maybe_update(doc, user) do
 222     if "true" == string_from_xpath("//author[1]/ap_enabled", doc) do
 223       Transmogrifier.upgrade_user_from_ap_id(user.ap_id)
 224     else
 225       maybe_update_ostatus(doc, user)
 226     end
 227   end
 228
 229   def maybe_update_ostatus(doc, user) do
 230     old_data = %{
 231       avatar: user.avatar,
 232       bio: user.bio,
 233       name: user.name
 234     }
 235
 236     with false <- user.local,
 237          avatar <- make_avatar_object(doc),
 238          bio <- string_from_xpath("//author[1]/summary", doc),
 239          name <- string_from_xpath("//author[1]/poco:displayName", doc),
 240          new_data <- %{
 241            avatar: avatar || old_data.avatar,
 242            name: name || old_data.name,
 243            bio: bio || old_data.bio
 244          },
 245          false <- new_data == old_data do
 246       change = Ecto.Changeset.change(user, new_data)
 247       User.update_and_set_cache(change)
 248     else
 249       _ ->
 250         {:ok, user}
 251     end
 252   end
 253
 254   def find_make_or_update_user(doc) do
 255     uri = string_from_xpath("//author/uri[1]", doc)
 256
 257     with {:ok, user} <- find_or_make_user(uri) do
 258       maybe_update(doc, user)
 259     end
 260   end
 261
 262   def find_or_make_user(uri) do
 263     query = from(user in User, where: user.ap_id == ^uri)
 264
 265     user = Repo.one(query)
 266
 267     if is_nil(user) do
 268       make_user(uri)
 269     else
 270       {:ok, user}
 271     end
 272   end
 273
 274   def make_user(uri, update \\ false) do
 275     with {:ok, info} <- gather_user_info(uri) do
 276       data = %{
 277         name: info["name"],
 278         nickname: info["nickname"] <> "@" <> info["host"],
 279         ap_id: info["uri"],
 280         info: info,
 281         avatar: info["avatar"],
 282         bio: info["bio"]
 283       }
 284
 285       with false <- update,
 286            %User{} = user <- User.get_by_ap_id(data.ap_id) do
 287         {:ok, user}
 288       else
 289         _e -> User.insert_or_update_user(data)
 290       end
 291     end
 292   end
 293
 294   # TODO: Just takes the first one for now.
 295   def make_avatar_object(author_doc, rel \\ "avatar") do
 296     href = string_from_xpath("//author[1]/link[@rel=\"#{rel}\"]/@href", author_doc)
 297     type = string_from_xpath("//author[1]/link[@rel=\"#{rel}\"]/@type", author_doc)
 298
 299     if href do
 300       %{
 301         "type" => "Image",
 302         "url" => [
 303           %{
 304             "type" => "Link",
 305             "mediaType" => type,
 306             "href" => href
 307           }
 308         ]
 309       }
 310     else
 311       nil
 312     end
 313   end
 314
 315   def gather_user_info(username) do
 316     with {:ok, webfinger_data} <- WebFinger.finger(username),
 317          {:ok, feed_data} <- Websub.gather_feed_data(webfinger_data["topic"]) do
 318       {:ok, Map.merge(webfinger_data, feed_data) |> Map.put("fqn", username)}
 319     else
 320       e ->
 321         Logger.debug(fn -> "Couldn't gather info for #{username}" end)
 322         {:error, e}
 323     end
 324   end
 325
 326   # Regex-based 'parsing' so we don't have to pull in a full html parser
 327   # It's a hack anyway. Maybe revisit this in the future
 328   @mastodon_regex ~r/<link href='(.*)' rel='alternate' type='application\/atom\+xml'>/
 329   @gs_regex ~r/<link title=.* href="(.*)" type="application\/atom\+xml" rel="alternate">/
 330   @gs_classic_regex ~r/<link rel="alternate" href="(.*)" type="application\/atom\+xml" title=.*>/
 331   def get_atom_url(body) do
 332     cond do
 333       Regex.match?(@mastodon_regex, body) ->
 334         [[_, match]] = Regex.scan(@mastodon_regex, body)
 335         {:ok, match}
 336
 337       Regex.match?(@gs_regex, body) ->
 338         [[_, match]] = Regex.scan(@gs_regex, body)
 339         {:ok, match}
 340
 341       Regex.match?(@gs_classic_regex, body) ->
 342         [[_, match]] = Regex.scan(@gs_classic_regex, body)
 343         {:ok, match}
 344
 345       true ->
 346         Logger.debug(fn -> "Couldn't find Atom link in #{inspect(body)}" end)
 347         {:error, "Couldn't find the Atom link"}
 348     end
 349   end
 350
 351   def fetch_activity_from_atom_url(url) do
 352     with true <- String.starts_with?(url, "http"),
 353          {:ok, %{body: body, status: code}} when code in 200..299 <-
 354            @httpoison.get(
 355              url,
 356              [{:Accept, "application/atom+xml"}]
 357            ) do
 358       Logger.debug("Got document from #{url}, handling...")
 359       handle_incoming(body)
 360     else
 361       e ->
 362         Logger.debug("Couldn't get #{url}: #{inspect(e)}")
 363         e
 364     end
 365   end
 366
 367   def fetch_activity_from_html_url(url) do
 368     Logger.debug("Trying to fetch #{url}")
 369
 370     with true <- String.starts_with?(url, "http"),
 371          {:ok, %{body: body}} <- @httpoison.get(url, []),
 372          {:ok, atom_url} <- get_atom_url(body) do
 373       fetch_activity_from_atom_url(atom_url)
 374     else
 375       e ->
 376         Logger.debug("Couldn't get #{url}: #{inspect(e)}")
 377         e
 378     end
 379   end
 380
 381   def fetch_activity_from_url(url) do
 382     with {:ok, [_ | _] = activities} <- fetch_activity_from_atom_url(url) do
 383       {:ok, activities}
 384     else
 385       _e -> fetch_activity_from_html_url(url)
 386     end
 387   rescue
 388     e ->
 389       Logger.debug("Couldn't get #{url}: #{inspect(e)}")
 390       {:error, "Couldn't get #{url}: #{inspect(e)}"}
 391   end
 392 end