akkoma/lib/pleroma/web/activity_pub/activity_pub.ex
Haelwenn (lanodan) Monnier 8bcfac93a8
Make credo happy
2019-02-09 14:59:20 +01:00

926 lines
27 KiB
Elixir

# Pleroma: A lightweight social networking server
# Copyright © 2017-2019 Pleroma Authors <https://pleroma.social/>
# SPDX-License-Identifier: AGPL-3.0-only
defmodule Pleroma.Web.ActivityPub.ActivityPub do
alias Pleroma.{Activity, Repo, Object, Upload, User, Notification, Instances}
alias Pleroma.Web.ActivityPub.{Transmogrifier, MRF}
alias Pleroma.Web.WebFinger
alias Pleroma.Web.Federator
alias Pleroma.Web.OStatus
import Ecto.Query
import Pleroma.Web.ActivityPub.Utils
require Logger
@httpoison Application.get_env(:pleroma, :httpoison)
# For Announce activities, we filter the recipients based on following status for any actors
# that match actual users. See issue #164 for more information about why this is necessary.
defp get_recipients(%{"type" => "Announce"} = data) do
to = data["to"] || []
cc = data["cc"] || []
recipients = to ++ cc
actor = User.get_cached_by_ap_id(data["actor"])
recipients
|> Enum.filter(fn recipient ->
case User.get_cached_by_ap_id(recipient) do
nil ->
true
user ->
User.following?(user, actor)
end
end)
{recipients, to, cc}
end
defp get_recipients(%{"type" => "Create"} = data) do
to = data["to"] || []
cc = data["cc"] || []
actor = data["actor"] || []
recipients = (to ++ cc ++ [actor]) |> Enum.uniq()
{recipients, to, cc}
end
defp get_recipients(data) do
to = data["to"] || []
cc = data["cc"] || []
recipients = to ++ cc
{recipients, to, cc}
end
defp check_actor_is_active(actor) do
if not is_nil(actor) do
with user <- User.get_cached_by_ap_id(actor),
false <- user.info.deactivated do
:ok
else
_e -> :reject
end
else
:ok
end
end
defp check_remote_limit(%{"object" => %{"content" => content}}) when not is_nil(content) do
limit = Pleroma.Config.get([:instance, :remote_limit])
String.length(content) <= limit
end
defp check_remote_limit(_), do: true
def insert(map, local \\ true) when is_map(map) do
with nil <- Activity.normalize(map),
map <- lazy_put_activity_defaults(map),
:ok <- check_actor_is_active(map["actor"]),
{_, true} <- {:remote_limit_error, check_remote_limit(map)},
{:ok, map} <- MRF.filter(map),
:ok <- insert_full_object(map) do
{recipients, _, _} = get_recipients(map)
{:ok, activity} =
Repo.insert(%Activity{
data: map,
local: local,
actor: map["actor"],
recipients: recipients
})
Task.start(fn ->
Pleroma.Web.RichMedia.Helpers.fetch_data_for_activity(activity)
end)
Notification.create_notifications(activity)
stream_out(activity)
{:ok, activity}
else
%Activity{} = activity -> {:ok, activity}
error -> {:error, error}
end
end
def stream_out(activity) do
public = "https://www.w3.org/ns/activitystreams#Public"
if activity.data["type"] in ["Create", "Announce", "Delete"] do
Pleroma.Web.Streamer.stream("user", activity)
Pleroma.Web.Streamer.stream("list", activity)
if Enum.member?(activity.data["to"], public) do
Pleroma.Web.Streamer.stream("public", activity)
if activity.local do
Pleroma.Web.Streamer.stream("public:local", activity)
end
if activity.data["type"] in ["Create"] do
activity.data["object"]
|> Map.get("tag", [])
|> Enum.filter(fn tag -> is_bitstring(tag) end)
|> Enum.each(fn tag -> Pleroma.Web.Streamer.stream("hashtag:" <> tag, activity) end)
if activity.data["object"]["attachment"] != [] do
Pleroma.Web.Streamer.stream("public:media", activity)
if activity.local do
Pleroma.Web.Streamer.stream("public:local:media", activity)
end
end
end
else
if !Enum.member?(activity.data["cc"] || [], public) &&
!Enum.member?(
activity.data["to"],
User.get_by_ap_id(activity.data["actor"]).follower_address
),
do: Pleroma.Web.Streamer.stream("direct", activity)
end
end
end
def create(%{to: to, actor: actor, context: context, object: object} = params) do
additional = params[:additional] || %{}
# only accept false as false value
local = !(params[:local] == false)
published = params[:published]
with create_data <-
make_create_data(
%{to: to, actor: actor, published: published, context: context, object: object},
additional
),
{:ok, activity} <- insert(create_data, local),
# Changing note count prior to enqueuing federation task in order to avoid race conditions on updating user.info
{:ok, _actor} <- User.increase_note_count(actor),
:ok <- maybe_federate(activity) do
{:ok, activity}
end
end
def accept(%{to: to, actor: actor, object: object} = params) do
# only accept false as false value
local = !(params[:local] == false)
with data <- %{"to" => to, "type" => "Accept", "actor" => actor, "object" => object},
{:ok, activity} <- insert(data, local),
:ok <- maybe_federate(activity) do
{:ok, activity}
end
end
def reject(%{to: to, actor: actor, object: object} = params) do
# only accept false as false value
local = !(params[:local] == false)
with data <- %{"to" => to, "type" => "Reject", "actor" => actor, "object" => object},
{:ok, activity} <- insert(data, local),
:ok <- maybe_federate(activity) do
{:ok, activity}
end
end
def update(%{to: to, cc: cc, actor: actor, object: object} = params) do
# only accept false as false value
local = !(params[:local] == false)
with data <- %{
"to" => to,
"cc" => cc,
"type" => "Update",
"actor" => actor,
"object" => object
},
{:ok, activity} <- insert(data, local),
:ok <- maybe_federate(activity) do
{:ok, activity}
end
end
# TODO: This is weird, maybe we shouldn't check here if we can make the activity.
def like(
%User{ap_id: ap_id} = user,
%Object{data: %{"id" => _}} = object,
activity_id \\ nil,
local \\ true
) do
with nil <- get_existing_like(ap_id, object),
like_data <- make_like_data(user, object, activity_id),
{:ok, activity} <- insert(like_data, local),
{:ok, object} <- add_like_to_object(activity, object),
:ok <- maybe_federate(activity) do
{:ok, activity, object}
else
%Activity{} = activity -> {:ok, activity, object}
error -> {:error, error}
end
end
def unlike(
%User{} = actor,
%Object{} = object,
activity_id \\ nil,
local \\ true
) do
with %Activity{} = like_activity <- get_existing_like(actor.ap_id, object),
unlike_data <- make_unlike_data(actor, like_activity, activity_id),
{:ok, unlike_activity} <- insert(unlike_data, local),
{:ok, _activity} <- Repo.delete(like_activity),
{:ok, object} <- remove_like_from_object(like_activity, object),
:ok <- maybe_federate(unlike_activity) do
{:ok, unlike_activity, like_activity, object}
else
_e -> {:ok, object}
end
end
def announce(
%User{ap_id: _} = user,
%Object{data: %{"id" => _}} = object,
activity_id \\ nil,
local \\ true,
public \\ true
) do
with true <- is_public?(object),
announce_data <- make_announce_data(user, object, activity_id, public),
{:ok, activity} <- insert(announce_data, local),
{:ok, object} <- add_announce_to_object(activity, object),
:ok <- maybe_federate(activity) do
{:ok, activity, object}
else
error -> {:error, error}
end
end
def unannounce(
%User{} = actor,
%Object{} = object,
activity_id \\ nil,
local \\ true
) do
with %Activity{} = announce_activity <- get_existing_announce(actor.ap_id, object),
unannounce_data <- make_unannounce_data(actor, announce_activity, activity_id),
{:ok, unannounce_activity} <- insert(unannounce_data, local),
:ok <- maybe_federate(unannounce_activity),
{:ok, _activity} <- Repo.delete(announce_activity),
{:ok, object} <- remove_announce_from_object(announce_activity, object) do
{:ok, unannounce_activity, object}
else
_e -> {:ok, object}
end
end
def follow(follower, followed, activity_id \\ nil, local \\ true) do
with data <- make_follow_data(follower, followed, activity_id),
{:ok, activity} <- insert(data, local),
:ok <- maybe_federate(activity) do
{:ok, activity}
end
end
def unfollow(follower, followed, activity_id \\ nil, local \\ true) do
with %Activity{} = follow_activity <- fetch_latest_follow(follower, followed),
{:ok, follow_activity} <- update_follow_state(follow_activity, "cancelled"),
unfollow_data <- make_unfollow_data(follower, followed, follow_activity, activity_id),
{:ok, activity} <- insert(unfollow_data, local),
:ok <- maybe_federate(activity) do
{:ok, activity}
end
end
def delete(%Object{data: %{"id" => id, "actor" => actor}} = object, local \\ true) do
user = User.get_cached_by_ap_id(actor)
data = %{
"type" => "Delete",
"actor" => actor,
"object" => id,
"to" => [user.follower_address, "https://www.w3.org/ns/activitystreams#Public"]
}
with {:ok, _} <- Object.delete(object),
{:ok, activity} <- insert(data, local),
# Changing note count prior to enqueuing federation task in order to avoid race conditions on updating user.info
{:ok, _actor} <- User.decrease_note_count(user),
:ok <- maybe_federate(activity) do
{:ok, activity}
end
end
def block(blocker, blocked, activity_id \\ nil, local \\ true) do
ap_config = Application.get_env(:pleroma, :activitypub)
unfollow_blocked = Keyword.get(ap_config, :unfollow_blocked)
outgoing_blocks = Keyword.get(ap_config, :outgoing_blocks)
with true <- unfollow_blocked do
follow_activity = fetch_latest_follow(blocker, blocked)
if follow_activity do
unfollow(blocker, blocked, nil, local)
end
end
with true <- outgoing_blocks,
block_data <- make_block_data(blocker, blocked, activity_id),
{:ok, activity} <- insert(block_data, local),
:ok <- maybe_federate(activity) do
{:ok, activity}
else
_e -> {:ok, nil}
end
end
def unblock(blocker, blocked, activity_id \\ nil, local \\ true) do
with %Activity{} = block_activity <- fetch_latest_block(blocker, blocked),
unblock_data <- make_unblock_data(blocker, blocked, block_activity, activity_id),
{:ok, activity} <- insert(unblock_data, local),
:ok <- maybe_federate(activity) do
{:ok, activity}
end
end
def fetch_activities_for_context(context, opts \\ %{}) do
public = ["https://www.w3.org/ns/activitystreams#Public"]
recipients =
if opts["user"], do: [opts["user"].ap_id | opts["user"].following] ++ public, else: public
query = from(activity in Activity)
query =
query
|> restrict_blocked(opts)
|> restrict_recipients(recipients, opts["user"])
query =
from(
activity in query,
where:
fragment(
"?->>'type' = ? and ?->>'context' = ?",
activity.data,
"Create",
activity.data,
^context
),
order_by: [desc: :id]
)
Repo.all(query)
end
def fetch_public_activities(opts \\ %{}) do
q = fetch_activities_query(["https://www.w3.org/ns/activitystreams#Public"], opts)
q
|> restrict_unlisted()
|> Repo.all()
|> Enum.reverse()
end
@valid_visibilities ~w[direct unlisted public private]
defp restrict_visibility(query, %{visibility: visibility})
when visibility in @valid_visibilities do
query =
from(
a in query,
where:
fragment("activity_visibility(?, ?, ?) = ?", a.actor, a.recipients, a.data, ^visibility)
)
Ecto.Adapters.SQL.to_sql(:all, Repo, query)
query
end
defp restrict_visibility(_query, %{visibility: visibility})
when visibility not in @valid_visibilities do
Logger.error("Could not restrict visibility to #{visibility}")
end
defp restrict_visibility(query, _visibility), do: query
def fetch_user_activities(user, reading_user, params \\ %{}) do
params =
params
|> Map.put("type", ["Create", "Announce"])
|> Map.put("actor_id", user.ap_id)
|> Map.put("whole_db", true)
|> Map.put("pinned_activity_ids", user.info.pinned_activities)
recipients =
if reading_user do
["https://www.w3.org/ns/activitystreams#Public"] ++
[reading_user.ap_id | reading_user.following]
else
["https://www.w3.org/ns/activitystreams#Public"]
end
fetch_activities(recipients, params)
|> Enum.reverse()
end
defp restrict_since(query, %{"since_id" => ""}), do: query
defp restrict_since(query, %{"since_id" => since_id}) do
from(activity in query, where: activity.id > ^since_id)
end
defp restrict_since(query, _), do: query
defp restrict_tag_reject(query, %{"tag_reject" => tag_reject})
when is_list(tag_reject) and tag_reject != [] do
from(
activity in query,
where: fragment("(not (? #> '{\"object\",\"tag\"}') \\?| ?)", activity.data, ^tag_reject)
)
end
defp restrict_tag_reject(query, _), do: query
defp restrict_tag_all(query, %{"tag_all" => tag_all})
when is_list(tag_all) and tag_all != [] do
from(
activity in query,
where: fragment("(? #> '{\"object\",\"tag\"}') \\?& ?", activity.data, ^tag_all)
)
end
defp restrict_tag_all(query, _), do: query
defp restrict_tag(query, %{"tag" => tag}) when is_list(tag) do
from(
activity in query,
where: fragment("(? #> '{\"object\",\"tag\"}') \\?| ?", activity.data, ^tag)
)
end
defp restrict_tag(query, %{"tag" => tag}) when is_binary(tag) do
from(
activity in query,
where: fragment("? <@ (? #> '{\"object\",\"tag\"}')", ^tag, activity.data)
)
end
defp restrict_tag(query, _), do: query
defp restrict_to_cc(query, recipients_to, recipients_cc) do
from(
activity in query,
where:
fragment(
"(?->'to' \\?| ?) or (?->'cc' \\?| ?)",
activity.data,
^recipients_to,
activity.data,
^recipients_cc
)
)
end
defp restrict_recipients(query, [], _user), do: query
defp restrict_recipients(query, recipients, nil) do
from(activity in query, where: fragment("? && ?", ^recipients, activity.recipients))
end
defp restrict_recipients(query, recipients, user) do
from(
activity in query,
where: fragment("? && ?", ^recipients, activity.recipients),
or_where: activity.actor == ^user.ap_id
)
end
defp restrict_limit(query, %{"limit" => limit}) do
from(activity in query, limit: ^limit)
end
defp restrict_limit(query, _), do: query
defp restrict_local(query, %{"local_only" => true}) do
from(activity in query, where: activity.local == true)
end
defp restrict_local(query, _), do: query
defp restrict_max(query, %{"max_id" => ""}), do: query
defp restrict_max(query, %{"max_id" => max_id}) do
from(activity in query, where: activity.id < ^max_id)
end
defp restrict_max(query, _), do: query
defp restrict_actor(query, %{"actor_id" => actor_id}) do
from(activity in query, where: activity.actor == ^actor_id)
end
defp restrict_actor(query, _), do: query
defp restrict_type(query, %{"type" => type}) when is_binary(type) do
from(activity in query, where: fragment("?->>'type' = ?", activity.data, ^type))
end
defp restrict_type(query, %{"type" => type}) do
from(activity in query, where: fragment("?->>'type' = ANY(?)", activity.data, ^type))
end
defp restrict_type(query, _), do: query
defp restrict_favorited_by(query, %{"favorited_by" => ap_id}) do
from(
activity in query,
where: fragment("? <@ (? #> '{\"object\",\"likes\"}')", ^ap_id, activity.data)
)
end
defp restrict_favorited_by(query, _), do: query
defp restrict_media(query, %{"only_media" => val}) when val == "true" or val == "1" do
from(
activity in query,
where: fragment("not (? #> '{\"object\",\"attachment\"}' = ?)", activity.data, ^[])
)
end
defp restrict_media(query, _), do: query
defp restrict_replies(query, %{"exclude_replies" => val}) when val == "true" or val == "1" do
from(
activity in query,
where: fragment("?->'object'->>'inReplyTo' is null", activity.data)
)
end
defp restrict_replies(query, _), do: query
defp restrict_reblogs(query, %{"exclude_reblogs" => val}) when val == "true" or val == "1" do
from(activity in query, where: fragment("?->>'type' != 'Announce'", activity.data))
end
defp restrict_reblogs(query, _), do: query
defp restrict_blocked(query, %{"blocking_user" => %User{info: info}}) do
blocks = info.blocks || []
domain_blocks = info.domain_blocks || []
from(
activity in query,
where: fragment("not (? = ANY(?))", activity.actor, ^blocks),
where: fragment("not (?->'to' \\?| ?)", activity.data, ^blocks),
where: fragment("not (split_part(?, '/', 3) = ANY(?))", activity.actor, ^domain_blocks)
)
end
defp restrict_blocked(query, _), do: query
defp restrict_unlisted(query) do
from(
activity in query,
where:
fragment(
"not (coalesce(?->'cc', '{}'::jsonb) \\?| ?)",
activity.data,
^["https://www.w3.org/ns/activitystreams#Public"]
)
)
end
defp restrict_pinned(query, %{"pinned" => "true", "pinned_activity_ids" => ids}) do
from(activity in query, where: activity.id in ^ids)
end
defp restrict_pinned(query, _), do: query
def fetch_activities_query(recipients, opts \\ %{}) do
base_query =
from(
activity in Activity,
limit: 20,
order_by: [fragment("? desc nulls last", activity.id)]
)
base_query
|> restrict_recipients(recipients, opts["user"])
|> restrict_tag(opts)
|> restrict_tag_reject(opts)
|> restrict_tag_all(opts)
|> restrict_since(opts)
|> restrict_local(opts)
|> restrict_limit(opts)
|> restrict_max(opts)
|> restrict_actor(opts)
|> restrict_type(opts)
|> restrict_favorited_by(opts)
|> restrict_blocked(opts)
|> restrict_media(opts)
|> restrict_visibility(opts)
|> restrict_replies(opts)
|> restrict_reblogs(opts)
|> restrict_pinned(opts)
end
def fetch_activities(recipients, opts \\ %{}) do
fetch_activities_query(recipients, opts)
|> Repo.all()
|> Enum.reverse()
end
def fetch_activities_bounded(recipients_to, recipients_cc, opts \\ %{}) do
fetch_activities_query([], opts)
|> restrict_to_cc(recipients_to, recipients_cc)
|> Repo.all()
|> Enum.reverse()
end
def upload(file, opts \\ []) do
with {:ok, data} <- Upload.store(file, opts) do
obj_data =
if opts[:actor] do
Map.put(data, "actor", opts[:actor])
else
data
end
Repo.insert(%Object{data: obj_data})
end
end
def user_data_from_user_object(data) do
avatar =
data["icon"]["url"] &&
%{
"type" => "Image",
"url" => [%{"href" => data["icon"]["url"]}]
}
banner =
data["image"]["url"] &&
%{
"type" => "Image",
"url" => [%{"href" => data["image"]["url"]}]
}
locked = data["manuallyApprovesFollowers"] || false
data = Transmogrifier.maybe_fix_user_object(data)
user_data = %{
ap_id: data["id"],
info: %{
"ap_enabled" => true,
"source_data" => data,
"banner" => banner,
"locked" => locked
},
avatar: avatar,
name: data["name"],
follower_address: data["followers"],
bio: data["summary"]
}
# nickname can be nil because of virtual actors
user_data =
if data["preferredUsername"] do
Map.put(
user_data,
:nickname,
"#{data["preferredUsername"]}@#{URI.parse(data["id"]).host}"
)
else
Map.put(user_data, :nickname, nil)
end
{:ok, user_data}
end
def fetch_and_prepare_user_from_ap_id(ap_id) do
with {:ok, data} <- fetch_and_contain_remote_object_from_id(ap_id) do
user_data_from_user_object(data)
else
e -> Logger.error("Could not decode user at fetch #{ap_id}, #{inspect(e)}")
end
end
def make_user_from_ap_id(ap_id) do
if _user = User.get_by_ap_id(ap_id) do
Transmogrifier.upgrade_user_from_ap_id(ap_id)
else
with {:ok, data} <- fetch_and_prepare_user_from_ap_id(ap_id) do
User.insert_or_update_user(data)
else
e -> {:error, e}
end
end
end
def make_user_from_nickname(nickname) do
with {:ok, %{"ap_id" => ap_id}} when not is_nil(ap_id) <- WebFinger.finger(nickname) do
make_user_from_ap_id(ap_id)
else
_e -> {:error, "No AP id in WebFinger"}
end
end
def should_federate?(inbox, public) do
if public do
true
else
inbox_info = URI.parse(inbox)
!Enum.member?(Pleroma.Config.get([:instance, :quarantined_instances], []), inbox_info.host)
end
end
def publish(actor, activity) do
remote_followers =
if actor.follower_address in activity.recipients do
{:ok, followers} = User.get_followers(actor)
followers |> Enum.filter(&(!&1.local))
else
[]
end
public = is_public?(activity)
reachable_inboxes_metadata =
(Pleroma.Web.Salmon.remote_users(activity) ++ remote_followers)
|> Enum.filter(fn user -> User.ap_enabled?(user) end)
|> Enum.map(fn %{info: %{source_data: data}} ->
(is_map(data["endpoints"]) && Map.get(data["endpoints"], "sharedInbox")) || data["inbox"]
end)
|> Enum.uniq()
|> Enum.filter(fn inbox -> should_federate?(inbox, public) end)
|> Instances.filter_reachable()
{:ok, data} = Transmogrifier.prepare_outgoing(activity.data)
json = Jason.encode!(data)
Enum.each(reachable_inboxes_metadata, fn {inbox, unreachable_since} ->
Federator.enqueue(:publish_single_ap, %{
inbox: inbox,
json: json,
actor: actor,
id: activity.data["id"],
unreachable_since: unreachable_since
})
end)
end
def publish_one(%{inbox: inbox, json: json, actor: actor, id: id} = params) do
Logger.info("Federating #{id} to #{inbox}")
host = URI.parse(inbox).host
digest = "SHA-256=" <> (:crypto.hash(:sha256, json) |> Base.encode64())
signature =
Pleroma.Web.HTTPSignatures.sign(actor, %{
host: host,
"content-length": byte_size(json),
digest: digest
})
with {:ok, %{status: code}} when code in 200..299 <-
result =
@httpoison.post(
inbox,
json,
[
{"Content-Type", "application/activity+json"},
{"signature", signature},
{"digest", digest}
]
) do
if !Map.has_key?(params, :unreachable_since) || params[:unreachable_since],
do: Instances.set_reachable(inbox)
result
else
{_post_result, response} ->
unless params[:unreachable_since], do: Instances.set_unreachable(inbox)
{:error, response}
end
end
# TODO:
# This will create a Create activity, which we need internally at the moment.
def fetch_object_from_id(id) do
if object = Object.get_cached_by_ap_id(id) do
{:ok, object}
else
Logger.info("Fetching #{id} via AP")
with {:ok, data} <- fetch_and_contain_remote_object_from_id(id),
nil <- Object.normalize(data),
params <- %{
"type" => "Create",
"to" => data["to"],
"cc" => data["cc"],
"actor" => data["actor"] || data["attributedTo"],
"object" => data
},
:ok <- Transmogrifier.contain_origin(id, params),
{:ok, activity} <- Transmogrifier.handle_incoming(params) do
{:ok, Object.normalize(activity.data["object"])}
else
{:error, {:reject, nil}} ->
{:reject, nil}
object = %Object{} ->
{:ok, object}
_e ->
Logger.info("Couldn't get object via AP, trying out OStatus fetching...")
case OStatus.fetch_activity_from_url(id) do
{:ok, [activity | _]} -> {:ok, Object.normalize(activity.data["object"])}
e -> e
end
end
end
end
def fetch_and_contain_remote_object_from_id(id) do
Logger.info("Fetching #{id} via AP")
with true <- String.starts_with?(id, "http"),
{:ok, %{body: body, status: code}} when code in 200..299 <-
@httpoison.get(
id,
[{:Accept, "application/activity+json"}]
),
{:ok, data} <- Jason.decode(body),
:ok <- Transmogrifier.contain_origin_from_id(id, data) do
{:ok, data}
else
e ->
{:error, e}
end
end
def is_public?(%Object{data: %{"type" => "Tombstone"}}), do: false
def is_public?(%Object{data: data}), do: is_public?(data)
def is_public?(%Activity{data: data}), do: is_public?(data)
def is_public?(%{"directMessage" => true}), do: false
def is_public?(data) do
"https://www.w3.org/ns/activitystreams#Public" in (data["to"] ++ (data["cc"] || []))
end
def is_private?(activity) do
!is_public?(activity) && Enum.any?(activity.data["to"], &String.contains?(&1, "/followers"))
end
def is_direct?(%Activity{data: %{"directMessage" => true}}), do: true
def is_direct?(%Object{data: %{"directMessage" => true}}), do: true
def is_direct?(activity) do
!is_public?(activity) && !is_private?(activity)
end
def visible_for_user?(activity, nil) do
is_public?(activity)
end
def visible_for_user?(activity, user) do
x = [user.ap_id | user.following]
y = activity.data["to"] ++ (activity.data["cc"] || [])
visible_for_user?(activity, nil) || Enum.any?(x, &(&1 in y))
end
# guard
def entire_thread_visible_for_user?(nil, _user), do: false
# child
def entire_thread_visible_for_user?(
%Activity{data: %{"object" => %{"inReplyTo" => parent_id}}} = tail,
user
)
when is_binary(parent_id) do
parent = Activity.get_in_reply_to_activity(tail)
visible_for_user?(tail, user) && entire_thread_visible_for_user?(parent, user)
end
# root
def entire_thread_visible_for_user?(tail, user), do: visible_for_user?(tail, user)
# filter out broken threads
def contain_broken_threads(%Activity{} = activity, %User{} = user) do
entire_thread_visible_for_user?(activity, user)
end
# do post-processing on a specific activity
def contain_activity(%Activity{} = activity, %User{} = user) do
contain_broken_threads(activity, user)
end
# do post-processing on a timeline
def contain_timeline(timeline, user) do
timeline
|> Enum.filter(fn activity ->
contain_activity(activity, user)
end)
end
end