Lingo.Event (Lingo v0.4.2)

The events Lingo.Bot.handle_event/2 receives: every one Discord sends, named as Discord names it, lowercased.

def handle_event(:message_create, %Lingo.Type.Message{content: "!ping"} = msg),
  do: Lingo.Api.Message.create(msg.channel_id, "Pong!")

def handle_event(:message_delete, %Lingo.Event.MessageDelete{old: %{content: content}}),
  do: Logger.info("deleted: #{content}")

def handle_event(:message_update, %{old: old, new: new}), do: ...

A payload takes one of three shapes:

a resource (Lingo.Type.Message, Lingo.Type.Channel, ...), the same struct Lingo.Api returns, when Discord sends one: creates, and deletes that carry the whole object, such as :channel_delete.
%{old: t | nil, new: t} for updates of a resource.
a struct of its own in Lingo.Event, named after Discord's event objects, for everything else: deletes that carry only ids, bans, reactions, typing and so on.

`old`

Updates, and deletes that carry only ids, include old: the resource as the cache held it just before the change. It's nil when it wasn't cached: the resource is disabled (nothing is cached by default, see Lingo.Cache), filtered out or evicted, or Lingo never saw it. So nil means unknown, never empty, and a handler that needs old should match nil too. Without a cache, new in :message_update holds only the fields Discord sent.

Unknown events

Events newer than Lingo arrive as :unknown, with a Lingo.Event.Unknown holding Discord's name and raw payload.

Lingo's own happenings (shards connecting and disconnecting, API rate limits) are not events but Lingo.Telemetry events; to wait until every shard is up, use Lingo.Gateway.await_ready/1.

Gateway events

Event	Payload
`:ready`	`Lingo.Event.Ready`
`:resumed`	`Lingo.Event.Resumed`
`:application_command_permissions_update`	`Lingo.Type.CommandPermissions`
`:auto_moderation_rule_create`	`Lingo.Type.AutoModerationRule`
`:auto_moderation_rule_update`	`%{old: old, new: new}` of `Lingo.Type.AutoModerationRule`
`:auto_moderation_rule_delete`	`Lingo.Type.AutoModerationRule`
`:auto_moderation_action_execution`	`Lingo.Event.AutoModerationAction`
`:channel_create`	`Lingo.Type.Channel`
`:channel_update`	`%{old: old, new: new}` of `Lingo.Type.Channel`
`:channel_delete`	`Lingo.Type.Channel`
`:channel_info`	`Lingo.Event.ChannelInfo`
`:channel_pins_update`	`Lingo.Event.ChannelPinsUpdate`
`:thread_create`	`Lingo.Type.Channel`
`:thread_update`	`%{old: old, new: new}` of `Lingo.Type.Channel`
`:thread_delete`	`Lingo.Event.ThreadDelete`
`:thread_list_sync`	`Lingo.Event.ThreadListSync`
`:thread_member_update`	`Lingo.Type.ThreadMember`
`:thread_members_update`	`Lingo.Event.ThreadMembersUpdate`
`:entitlement_create`	`Lingo.Type.Entitlement`
`:entitlement_update`	`%{old: old, new: new}` of `Lingo.Type.Entitlement`
`:entitlement_delete`	`Lingo.Type.Entitlement`
`:guild_create`	`Lingo.Type.Guild`
`:guild_update`	`%{old: old, new: new}` of `Lingo.Type.Guild`
`:guild_delete`	`Lingo.Event.GuildDelete`
`:guild_audit_log_entry_create`	`Lingo.Type.AuditLogEntry`
`:guild_ban_add`	`Lingo.Event.GuildBan`
`:guild_ban_remove`	`Lingo.Event.GuildBan`
`:guild_emojis_update`	`Lingo.Event.GuildEmojisUpdate`
`:guild_stickers_update`	`Lingo.Event.GuildStickersUpdate`
`:guild_integrations_update`	`Lingo.Event.GuildIntegrationsUpdate`
`:guild_member_add`	`Lingo.Type.Member`
`:guild_member_update`	`%{old: old, new: new}` of `Lingo.Type.Member`
`:guild_member_remove`	`Lingo.Event.GuildMemberRemove`
`:guild_members_chunk`	`Lingo.Event.GuildMembersChunk`
`:guild_role_create`	`Lingo.Type.Role`
`:guild_role_update`	`%{old: old, new: new}` of `Lingo.Type.Role`
`:guild_role_delete`	`Lingo.Event.GuildRoleDelete`
`:guild_scheduled_event_create`	`Lingo.Type.ScheduledEvent`
`:guild_scheduled_event_update`	`%{old: old, new: new}` of `Lingo.Type.ScheduledEvent`
`:guild_scheduled_event_delete`	`Lingo.Type.ScheduledEvent`
`:guild_scheduled_event_user_add`	`Lingo.Event.ScheduledEventUser`
`:guild_scheduled_event_user_remove`	`Lingo.Event.ScheduledEventUser`
`:guild_soundboard_sound_create`	`Lingo.Type.SoundboardSound`
`:guild_soundboard_sound_update`	`%{old: old, new: new}` of `Lingo.Type.SoundboardSound`
`:guild_soundboard_sound_delete`	`Lingo.Event.SoundboardSoundDelete`
`:guild_soundboard_sounds_update`	`Lingo.Event.SoundboardSounds`
`:soundboard_sounds`	`Lingo.Event.SoundboardSounds`
`:integration_create`	`Lingo.Type.Integration`
`:integration_update`	`%{old: old, new: new}` of `Lingo.Type.Integration`
`:integration_delete`	`Lingo.Event.IntegrationDelete`
`:interaction_create`	`Lingo.Type.Interaction`
`:invite_create`	`Lingo.Type.Invite`
`:invite_delete`	`Lingo.Event.InviteDelete`
`:message_create`	`Lingo.Type.Message`
`:message_update`	`%{old: old, new: new}` of `Lingo.Type.Message`
`:message_delete`	`Lingo.Event.MessageDelete`
`:message_delete_bulk`	`Lingo.Event.MessageDeleteBulk`
`:message_reaction_add`	`Lingo.Event.Reaction`
`:message_reaction_remove`	`Lingo.Event.Reaction`
`:message_reaction_remove_all`	`Lingo.Event.ReactionRemoveAll`
`:message_reaction_remove_emoji`	`Lingo.Event.Reaction`
`:message_poll_vote_add`	`Lingo.Event.PollVote`
`:message_poll_vote_remove`	`Lingo.Event.PollVote`
`:presence_update`	`%{old: old, new: new}` of `Lingo.Type.Presence`
`:rate_limited`	`Lingo.Event.RateLimited`
`:stage_instance_create`	`Lingo.Type.StageInstance`
`:stage_instance_update`	`%{old: old, new: new}` of `Lingo.Type.StageInstance`
`:stage_instance_delete`	`Lingo.Type.StageInstance`
`:subscription_create`	`Lingo.Type.Subscription`
`:subscription_update`	`%{old: old, new: new}` of `Lingo.Type.Subscription`
`:subscription_delete`	`Lingo.Type.Subscription`
`:typing_start`	`Lingo.Event.TypingStart`
`:user_update`	`%{old: old, new: new}` of `Lingo.Type.User`
`:voice_channel_effect_send`	`Lingo.Event.VoiceChannelEffect`
`:voice_channel_status_update`	`Lingo.Event.VoiceChannelStatus`
`:voice_channel_start_time_update`	`Lingo.Event.VoiceChannelStartTime`
`:voice_state_update`	`%{old: old, new: new}` of `Lingo.Type.VoiceState`
`:webhooks_update`	`Lingo.Event.WebhooksUpdate`

Webhook events

These come through Lingo.Endpoint's webhook events URL. Entitlement events come both ways: a bot with the gateway and webhook events on gets each one twice, so deduplicate by id or subscribe to one.

Event	Payload
`:application_authorized`	`Lingo.Event.ApplicationAuthorized`
`:application_deauthorized`	`Lingo.Event.ApplicationDeauthorized`
`:entitlement_create`	`Lingo.Type.Entitlement`
`:entitlement_update`	`%{old: old, new: new}` of `Lingo.Type.Entitlement`
`:entitlement_delete`	`Lingo.Type.Entitlement`
`:lobby_message_create`	`Lingo.Type.LobbyMessage`
`:lobby_message_update`	`%{old: old, new: new}` of `Lingo.Type.LobbyMessage`
`:lobby_message_delete`	`Lingo.Event.LobbyMessageDelete`
`:game_direct_message_create`	`Lingo.Type.Message`
`:game_direct_message_update`	`%{old: old, new: new}` of `Lingo.Type.Message`
`:game_direct_message_delete`	`Lingo.Type.Message`

Summary

Types

name()

An event's name.

payload()

An event's payload. The table above says which goes with which name.

update(t)

An update's payload: the resource before (from the cache, or nil) and after.