mobilizon/lib/service/export/feed.ex

177 lines
5.1 KiB
Elixir

defmodule Mobilizon.Service.Export.Feed do
@moduledoc """
Serve Atom Syndication Feeds.
"""
import MobilizonWeb.Gettext
alias Atomex.{Entry, Feed}
alias Mobilizon.{Actors, Events, Users}
alias Mobilizon.Actors.Actor
alias Mobilizon.Events.{Event, FeedToken}
alias Mobilizon.Users.User
alias MobilizonWeb.{Endpoint, MediaProxy}
alias MobilizonWeb.Router.Helpers, as: Routes
require Logger
@version Mix.Project.config()[:version]
def version, do: @version
@spec create_cache(String.t()) :: {:commit, String.t()} | {:ignore, any()}
def create_cache("actor_" <> name) do
case fetch_actor_event_feed(name) do
{:ok, res} ->
{:commit, res}
err ->
{:ignore, err}
end
end
@spec create_cache(String.t()) :: {:commit, String.t()} | {:ignore, any()}
def create_cache("token_" <> token) do
case fetch_events_from_token(token) do
{:ok, res} ->
{:commit, res}
err ->
{:ignore, err}
end
end
@spec fetch_actor_event_feed(String.t()) :: String.t()
defp fetch_actor_event_feed(name) do
with %Actor{} = actor <- Actors.get_local_actor_by_name(name),
{:visibility, true} <- {:visibility, Actor.is_public_visibility(actor)},
{:ok, events, _count} <- Events.list_public_events_for_actor(actor) do
{:ok, build_actor_feed(actor, events)}
else
err ->
{:error, err}
end
end
# Build an atom feed from actor and its public events
@spec build_actor_feed(Actor.t(), list(), boolean()) :: String.t()
defp build_actor_feed(%Actor{} = actor, events, public \\ true) do
display_name = Actor.display_name(actor)
self_url =
Endpoint
|> Routes.feed_url(:actor, actor.preferred_username, "atom")
|> URI.decode()
title =
if public,
do: "%{actor}'s public events feed on Mobilizon",
else: "%{actor}'s private events feed on Mobilizon"
# Title uses default instance language
feed =
self_url
|> Feed.new(
DateTime.utc_now(),
Gettext.gettext(MobilizonWeb.Gettext, title, actor: display_name)
)
|> Feed.author(display_name, uri: actor.url)
|> Feed.link(self_url, rel: "self")
|> Feed.link(actor.url, rel: "alternate")
|> Feed.generator("Mobilizon", uri: "https://joinmobilizon.org", version: version())
|> Feed.entries(Enum.map(events, &get_entry/1))
feed =
if actor.avatar do
feed |> Feed.icon(actor.avatar.url |> MediaProxy.url())
else
feed
end
feed =
if actor.banner do
feed |> Feed.logo(actor.banner.url |> MediaProxy.url())
else
feed
end
feed
|> Feed.build()
|> Atomex.generate_document()
end
# Create an entry for the Atom feed
@spec get_entry(Event.t()) :: any()
defp get_entry(%Event{} = event) do
description = event.description || ""
entry =
event.url
|> Entry.new(event.publish_at || event.inserted_at, event.title)
|> Entry.link(event.url, rel: "alternate", type: "text/html")
|> Entry.content({:cdata, description}, type: "html")
|> Entry.published(event.publish_at || event.inserted_at)
# Add tags
entry =
event.tags
|> Enum.uniq()
|> Enum.reduce(entry, fn tag, acc -> Entry.category(acc, tag.slug, label: tag.title) end)
Entry.build(entry)
end
@spec fetch_events_from_token(String.t()) :: String.t()
defp fetch_events_from_token(token) do
with {:ok, _uuid} <- Ecto.UUID.cast(token),
%FeedToken{actor: actor, user: %User{} = user} <- Events.get_feed_token(token) do
case actor do
%Actor{} = actor ->
events = actor |> fetch_identity_participations() |> participations_to_events()
{:ok, build_actor_feed(actor, events, false)}
nil ->
with actors <- Users.get_actors_for_user(user),
events <-
actors
|> Enum.map(fn actor ->
actor
|> Events.list_event_participations_for_actor()
|> participations_to_events()
end)
|> Enum.concat() do
{:ok, build_user_feed(events, user, token)}
end
end
end
end
defp fetch_identity_participations(%Actor{} = actor) do
with events <- Events.list_event_participations_for_actor(actor) do
events
end
end
defp participations_to_events(participations) do
participations
|> Enum.map(& &1.event_id)
|> Enum.map(&Events.get_event_with_preload!/1)
end
# Build an atom feed from actor and its public events
@spec build_user_feed(list(), User.t(), String.t()) :: String.t()
defp build_user_feed(events, %User{email: email}, token) do
self_url = Endpoint |> Routes.feed_url(:going, token, "atom") |> URI.decode()
# Title uses default instance language
self_url
|> Feed.new(DateTime.utc_now(), gettext("Feed for %{email} on Mobilizon", email: email))
|> Feed.link(self_url, rel: "self")
|> Feed.generator("Mobilizon", uri: "https://joinmobilizon.org", version: version())
|> Feed.entries(Enum.map(events, &get_entry/1))
|> Feed.build()
|> Atomex.generate_document()
end
end