mobilizon/lib/service/export/icalendar.ex

223 lines
6.1 KiB
Elixir

defmodule Mobilizon.Service.Export.ICalendar do
@moduledoc """
Export an event to iCalendar format.
"""
alias Mobilizon.Actors.Actor
alias Mobilizon.Addresses.Address
alias Mobilizon.{Config, Events}
alias Mobilizon.Events.{Event, EventOptions}
alias Mobilizon.Service.Export.{Cachable, Common}
alias Mobilizon.Service.Formatter.HTML
@behaviour Cachable
@item_limit 500
@doc """
Create cache for an actor, an event or an user token
"""
@impl Cachable
@spec create_cache(String.t()) :: {:commit, String.t()} | {:ignore, atom()}
def create_cache("actor_" <> name) do
case export_public_actor(name) do
{:ok, res} ->
{:commit, res}
{:error, err} ->
{:ignore, err}
end
end
@impl Cachable
def create_cache("event_" <> uuid) do
with %Event{} = event <- Events.get_public_event_by_uuid_with_preload(uuid),
{:ok, res} <- export_public_event(event) do
{:commit, res}
else
{:error, err} ->
{:ignore, err}
nil ->
{:ignore, :event_not_found}
end
end
@impl Cachable
def create_cache("token_" <> token) do
case fetch_events_from_token(token) do
{:ok, res} ->
{:commit, res}
{:error, err} ->
{:ignore, err}
end
end
@impl Cachable
def create_cache("instance") do
{:ok, res} = fetch_instance_feed()
{:commit, res}
end
@spec fetch_instance_feed :: {:ok, String.t()}
defp fetch_instance_feed do
{:ok, events, _posts} = Common.fetch_instance_public_content(@item_limit)
{:ok, %ICalendar{events: events |> Enum.map(&do_export_event/1)} |> ICalendar.to_ics()}
end
@doc """
Export an event to iCalendar format.
"""
@spec export_event(Event.t()) :: {:ok, String.t()}
def export_event(%Event{} = event), do: {:ok, events_to_ics([event])}
@doc """
Export a public event to iCalendar format.
The event must have a visibility of `:public` or `:unlisted`
"""
@spec export_public_event(Event.t()) :: {:ok, String.t()} | {:error, :event_not_public}
def export_public_event(%Event{visibility: visibility} = event)
when visibility in [:public, :unlisted] do
{:ok, events_to_ics([event])}
end
def export_public_event(%Event{}), do: {:error, :event_not_public}
# Export a public actor's events to iCalendar format.
# The actor must have a visibility of `:public` or `:unlisted`, as well as the events
@spec export_public_actor(String.t()) ::
{:ok, String.t()} | {:error, :actor_not_public | :actor_not_found}
defp export_public_actor(name, limit \\ @item_limit) do
case Common.fetch_actor_event_feed(name, limit) do
{:ok, _actor, events, _posts} ->
{:ok, events_to_ics(events)}
{:error, err} ->
{:error, err}
end
end
@spec fetch_events_from_token(String.t(), integer()) ::
{:ok, String.t()} | {:error, :actor_not_public | :actor_not_found}
defp fetch_events_from_token(token, limit \\ @item_limit) do
case Common.fetch_events_from_token(token, limit) do
%{events: events} ->
{:ok, events_to_ics(events)}
{:error, err} ->
{:error, err}
end
end
@spec events_to_ics(list(Events.t())) :: String.t()
defp events_to_ics(events) do
%ICalendar{events: events |> Enum.map(&do_export_event/1)}
|> ICalendar.to_ics(vendor: vendor())
end
@spec do_export_event(Event.t()) :: ICalendar.Event.t()
defp do_export_event(%Event{} = event) do
icalendar_event = %ICalendar.Event{
summary: event.title,
dtstart: begins_on(event),
dtstamp: event.publish_at || DateTime.utc_now(),
dtend: ends_on(event),
description: HTML.strip_tags(event.description),
uid: event.uuid,
url: event.url,
organizer: organizer(event)
}
icalendar_event =
if event.physical_address do
%ICalendar.Event{
icalendar_event
| geo: Address.coords(event.physical_address),
location: Address.representation(event.physical_address)
}
else
icalendar_event
end
icalendar_event =
if length(event.tags) > 0 do
%ICalendar.Event{icalendar_event | categories: event.tags |> Enum.map(& &1.title)}
else
icalendar_event
end
icalendar_event
end
@spec vendor :: String.t()
defp vendor do
"Mobilizon #{Config.instance_version()}"
end
defp begins_on(%Event{begins_on: begins_on, options: %EventOptions{timezone: timezone}}) do
shift_tz(begins_on, timezone)
end
defp ends_on(%Event{ends_on: ends_on, options: %EventOptions{timezone: timezone}}) do
shift_tz(ends_on, timezone)
end
defp shift_tz(%DateTime{} = date, timezone) when is_binary(timezone) do
DateTime.shift_zone!(date, timezone)
end
defp shift_tz(%DateTime{} = date, _), do: date
defp shift_tz(nil, _), do: nil
defp organizer(%Event{attributed_to: %Actor{} = group}) do
Actor.display_name(group)
end
defp organizer(%Event{organizer_actor: %Actor{} = profile}) do
Actor.display_name(profile)
end
@impl Cachable
@spec clear_caches(%{
:__struct__ => Mobilizon.Actors.Actor | Mobilizon.Events.Event | Mobilizon.Posts.Post,
optional(any) => any
}) :: {:error, boolean} | {:ok, boolean}
def clear_caches(%Event{attributed_to: %Actor{} = actor} = event) do
clear_actor_feed(actor)
clear_caches(%{event | attributed_to: nil})
end
@impl Cachable
def clear_caches(%Event{uuid: uuid}) do
# TODO: It would be nice to clear feed token cache based on participations as well,
# but that's harder, as it would require loading all participations
Cachex.del(:ics, "event_#{uuid}")
clear_instance()
end
# Not applicable for posts
@impl Cachable
def clear_caches(%Mobilizon.Posts.Post{}) do
{:ok, true}
end
@impl Cachable
def clear_caches(%Actor{} = actor) do
clear_actor_feed(actor)
clear_instance()
end
defp clear_instance do
Cachex.del(:ics, "instance")
end
defp clear_actor_feed(%Actor{preferred_username: preferred_username} = actor) do
if Actor.is_public_visibility?(actor) do
Cachex.del(:ics, "actor_#{preferred_username}")
end
end
end