mobilizon/lib/federation/activity_pub/refresher.ex

234 lines
7.5 KiB
Elixir

defmodule Mobilizon.Federation.ActivityPub.Refresher do
@moduledoc """
Module that provides functions to explore and fetch collections on a group
"""
alias Mobilizon.Actors
alias Mobilizon.Actors.Actor
alias Mobilizon.Federation.ActivityPub
alias Mobilizon.Federation.ActivityPub.Actor, as: ActivityPubActor
alias Mobilizon.Federation.ActivityPub.{Fetcher, Relay, Transmogrifier, Utils}
require Logger
@doc """
Refresh a remote profile
"""
@spec refresh_profile(Actor.t()) :: {:ok, Actor.t()} | {:error, fetch_actor_errors()} | {:error}
def refresh_profile(%Actor{domain: nil}), do: {:error, "Can only refresh remote actors"}
def refresh_profile(%Actor{type: :Group, url: url, id: group_id} = group) do
on_behalf_of =
case Actors.get_single_group_member_actor(group_id) do
%Actor{} = member_actor ->
member_actor
_ ->
Relay.get_actor()
end
case fetch_group(url, on_behalf_of) do
{:error, error} ->
{:error, error}
:ok ->
{:ok, group}
end
end
def refresh_profile(%Actor{type: type, url: url}) when type in [:Person, :Application] do
Logger.debug("Refreshing profile #{url}")
case ActivityPubActor.make_actor_from_url(url) do
{:error, error} ->
{:error, error}
{:ok, %Actor{outbox_url: outbox_url} = actor} ->
case fetch_collection(outbox_url, Relay.get_actor()) do
:ok -> {:ok, actor}
{:error, error} -> {:error, error}
end
end
end
@type fetch_actor_errors :: ActivityPubActor.make_actor_errors() | fetch_collection_errors()
@spec fetch_group(String.t(), Actor.t()) :: :ok | {:error, fetch_actor_errors}
def fetch_group(group_url, %Actor{} = on_behalf_of) do
Logger.debug("Fetching group #{group_url}")
case ActivityPubActor.make_actor_from_url(group_url, on_behalf_of: on_behalf_of) do
{:error, err}
when err in [:actor_deleted, :http_error, :json_decode_error, :actor_is_local] ->
Logger.debug("Error while making actor")
{:error, err}
{:ok,
%Actor{
outbox_url: outbox_url,
resources_url: resources_url,
members_url: members_url,
posts_url: posts_url,
todos_url: todos_url,
discussions_url: discussions_url,
events_url: events_url
}} ->
Logger.debug("Fetched group OK, now doing collections")
with :ok <- fetch_collection(outbox_url, on_behalf_of),
:ok <- fetch_collection(members_url, on_behalf_of),
:ok <- fetch_collection(resources_url, on_behalf_of),
:ok <- fetch_collection(posts_url, on_behalf_of),
:ok <- fetch_collection(todos_url, on_behalf_of),
:ok <- fetch_collection(discussions_url, on_behalf_of),
:ok <- fetch_collection(events_url, on_behalf_of) do
:ok
else
{:error, err}
when err in [:error, :process_error, :fetch_error, :collection_url_nil] ->
Logger.debug("Error while fetching actor collection")
{:error, err}
end
end
end
@typep fetch_collection_errors :: :process_error | :fetch_error | :collection_url_nil
@spec fetch_collection(String.t() | nil, any) ::
:ok | {:error, fetch_collection_errors}
def fetch_collection(nil, _on_behalf_of), do: {:error, :collection_url_nil}
def fetch_collection(collection_url, on_behalf_of) do
Logger.debug("Fetching and preparing collection from url")
Logger.debug(inspect(collection_url))
case Fetcher.fetch(collection_url, on_behalf_of: on_behalf_of) do
{:ok, data} when is_map(data) ->
Logger.debug("Fetch ok, passing to process_collection")
case process_collection(data, on_behalf_of) do
:ok ->
Logger.debug("Finished processing a collection")
:ok
:error ->
Logger.debug("Failed to process collection #{collection_url}")
{:error, :process_error}
end
{:error, _err} ->
Logger.debug("Failed to fetch collection #{collection_url}")
{:error, :fetch_error}
end
end
@spec fetch_element(String.t(), Actor.t()) :: {:ok, struct()} | {:error, any()}
def fetch_element(url, %Actor{} = on_behalf_of) do
with {:ok, data} <- Fetcher.fetch(url, on_behalf_of: on_behalf_of) do
case handling_element(data) do
{:ok, _activity, entity} ->
{:ok, entity}
{:ok, entity} ->
{:ok, entity}
:error ->
{:error, :err_fetching_element}
err ->
{:error, err}
end
end
end
@spec refresh_all_external_groups :: :ok
def refresh_all_external_groups do
Actors.list_external_groups()
|> Enum.filter(&Actors.needs_update?/1)
|> Enum.each(&refresh_profile/1)
end
@spec process_collection(map(), any()) :: :ok | :error
defp process_collection(%{"type" => type, "orderedItems" => items}, _on_behalf_of)
when type in ["OrderedCollection", "OrderedCollectionPage"] do
Logger.debug(
"Processing an OrderedCollection / OrderedCollectionPage with has direct orderedItems"
)
Logger.debug(inspect(items))
items
|> Enum.map(fn item -> Task.async(fn -> handling_element(item) end) end)
|> Task.await_many()
Logger.debug("Finished processing a collection")
:ok
end
# Lemmy uses an OrderedCollection with the items property
defp process_collection(%{"type" => type, "items" => items} = collection, on_behalf_of)
when type in ["OrderedCollection", "OrderedCollectionPage"] do
collection
|> Map.put("orderedItems", items)
|> process_collection(on_behalf_of)
end
defp process_collection(%{"type" => "OrderedCollection", "first" => first}, on_behalf_of)
when is_map(first),
do: process_collection(first, on_behalf_of)
defp process_collection(%{"type" => "OrderedCollection", "first" => first}, on_behalf_of)
when is_binary(first) do
Logger.debug("OrderedCollection has a first property pointing to an URI")
with {:ok, data} <- Fetcher.fetch(first, on_behalf_of: on_behalf_of) do
Logger.debug("Fetched the collection for first property")
process_collection(data, on_behalf_of)
end
end
defp process_collection(_, _), do: :error
# If we're handling an activity
@spec handling_element(map()) :: {:ok, any, struct} | :error
@spec handling_element(String.t()) :: {:ok, struct} | {:ok, atom, struct} | {:error, any()}
defp handling_element(%{"type" => activity_type} = data)
when activity_type in ["Create", "Update", "Delete"] do
object = get_in(data, ["object"])
if object do
object |> Utils.get_url() |> Mobilizon.Tombstone.delete_uri_tombstone()
end
Transmogrifier.handle_incoming(data)
end
# If we're handling an announce activity
defp handling_element(%{"type" => "Announce"} = data) do
handling_element(get_in(data, ["object"]))
end
# If we're handling directly an object
defp handling_element(data) when is_map(data) do
object = get_in(data, ["object"])
if object do
object |> Utils.get_url() |> Mobilizon.Tombstone.delete_uri_tombstone()
end
activity = %{
"type" => "Create",
"to" => data["to"],
"cc" => data["cc"],
"actor" => data["actor"] || data["attributedTo"],
"attributedTo" => data["attributedTo"] || data["actor"],
"object" => data
}
Transmogrifier.handle_incoming(activity)
end
defp handling_element(uri) when is_binary(uri) do
ActivityPub.fetch_object_from_url(uri)
end
end