Missing fields in AppMentionEvent

[phoebelilius]

AppMentionEvent may have attachments, if referenced by another bot.
Example payload:

{
    "api_app_id": "xxxx",
    "authorizations": [
        {
            "enterprise_id": "xxx",
            "is_bot": true,
            "is_enterprise_install": false,
            "team_id": "xxx",
            "user_id": "xxx"
        }
    ],
    "enterprise_id": "xxx",
    "event": {
        "attachments": [
            {
                "blocks": [
                    {
                        "block_id": "HNku",
                        "text": {
                            "text": "My test event CC <@MYBOTID>",
                            "type": "mrkdwn",
                            "verbatim": false
                        },
                        "type": "section"
                    }
                ],
                "color": "#29AF7B",
                "fallback": "[no preview available]",
                "id": 1
            }
        ],
        "bot_id": "xxx",
        "bot_profile": {
            "app_id": "xxx",
            "deleted": false,
            "icons": {
                "image_36": "https://slack-files2.s3-us-west-2.amazonaws.com/avatars/xxx"
            },
            "id": "xxx",
            "name": "xxx",
            "team_id": "xxx",
            "updated": 1562687282
        },
        "channel": "xxx",
        "edited": {
            "ts": "1628260114.000000",
            "user": "xxx"
        },
        "event_ts": "1628259917.003000",
        "team": "xxx",
        "text": "",
        "ts": "1628259917.003000",
        "type": "app_mention",
        "user": "xxx"
    },
    "event_context": "xxx",
    "event_id": "xxx",
    "event_time": 1628259917,
    "is_ext_shared_channel": false,
    "team_id": "xxx",
    "token": "xxx",
    "type": "event_callback"
}

slack/slackevents/inner_events.go

Lines 18 to 33 in 93fe17c

	type AppMentionEvent struct {
	Type string `json:"type"`
	User string `json:"user"`
	Text string `json:"text"`
	TimeStamp string `json:"ts"`
	ThreadTimeStamp string `json:"thread_ts"`
	Channel string `json:"channel"`
	EventTimeStamp json.Number `json:"event_ts"`
	// When Message comes from a channel that is shared between workspaces
	UserTeam string `json:"user_team,omitempty"`
	SourceTeam string `json:"source_team,omitempty"`
	// BotID is filled out when a bot triggers the app_mention event
	BotID string `json:"bot_id,omitempty"`
	}

Currently using ParseEvent can only parse inner events (AppMentionEvent) in the format:

{
    "api_app_id": "xxx",
    "authorizations": [
        {
            "enterprise_id": "xxx",
            "is_bot": true,
            "is_enterprise_install": false,
            "team_id": "xxx",
            "user_id": "xxx"
        }
    ],
    "enterprise_id": "xxx",
    "event": {
        "bot_id": "xxx",
        "channel": "xxx",
        "event_ts": "1628260061.003900",
        "subtype": "bot_message",
        "text": "CC <@BOTID> test",
        "ts": "1628260061.003900",
        "type": "app_mention",
        "username": "xxx"
    },
    "event_context": "xxx",
    "event_id": "xxx",
    "event_time": 1628260061,
    "is_ext_shared_channel": false,
    "team_id": "xxx",
    "token": "xxx",
    "type": "event_callback"
}

[phoebelilius]

I guess it would be a matter of adding Attachments []slack.Attachment `json:"attachments,omitempty".

[phoebelilius]

Actually I guess an app_mention event can have all the fields as in MessageEvent.

slack/slackevents/inner_events.go

Lines 101 to 139 in 93fe17c

	type MessageEvent struct {
	// Basic Message Event - https://api.slack.com/events/message
	ClientMsgID string `json:"client_msg_id"`
	Type string `json:"type"`
	User string `json:"user"`
	Text string `json:"text"`
	ThreadTimeStamp string `json:"thread_ts"`
	TimeStamp string `json:"ts"`
	Channel string `json:"channel"`
	ChannelType string `json:"channel_type"`
	EventTimeStamp json.Number `json:"event_ts"`
	// When Message comes from a channel that is shared between workspaces
	UserTeam string `json:"user_team,omitempty"`
	SourceTeam string `json:"source_team,omitempty"`
	// Edited Message
	Message *MessageEvent `json:"message,omitempty"`
	PreviousMessage *MessageEvent `json:"previous_message,omitempty"`
	Edited *Edited `json:"edited,omitempty"`
	// Message Subtypes
	SubType string `json:"subtype,omitempty"`
	// bot_message (https://api.slack.com/events/message/bot_message)
	BotID string `json:"bot_id,omitempty"`
	Username string `json:"username,omitempty"`
	Icons *Icon `json:"icons,omitempty"`
	Upload bool `json:"upload"`
	Files []File `json:"files"`
	Attachments []slack.Attachment `json:"attachments,omitempty"`
	// Root is the message that was broadcast to the channel when the SubType is
	// thread_broadcast. If this is not a thread_broadcast message event, this
	// value is nil.
	Root *MessageEvent `json:"root"`
	}

[chrisgoffinet]

Would it just make sense to make AppMentionEvent be this for consistency? It looks like the slack docs at https://api.slack.com/events/app_mention suggest:

The app_mention event is not a message like the message.* event types. However, your app can treat its contents similarly.

type AppMentionEvent struct {
  MessageEvent
}

I ran into this bug myself where I didn't reference another bot but blocks were missing that comes along in the payload by default.

[phoebelilius]

@chrisgoffinet I agree with you on that. The only issue would be that that would be a breaking change in the code unfortunately if the following would be implemented:

type AppMentionEvent struct {
  MessageEvent
}

I hope the maintainers of this repo would look into this!