Add Events API in socket mode for Slack adapter

[kolsys]

This is beta version for modern Slack applications. Changes implement Slack Events API in socket mode, see #964.

Fixes #2159 It also fixes files upload to Slack for modern Apps.

To activate Ecvents API in SocketMode you must:

1. Create new modern App with following OAuth Bot scope (or upgrade Legacy)

   channels:history
   channels:read
   chat:write
   files:read
   files:write
   groups:history
   groups:read
   im:history
   im:read
   mpim:history
   mpim:read
   users.profile:read
   users:read

2. Acivate Socket mode
3. Subscribe to the following events:

   channel_history_changed
   group_history_changed
   im_history_changed  
   message.channels
   message.groups
   message.im
   message.mpim

4. Add AppToken to the toml:

   
   [slack]
   [slack.mybot]
   Token="xoxb-*******"
   AppToken="xapp-**********"

[codeclimate[bot]]

Code Climate has analyzed commit 5b86262f and detected 4 issues on this pull request.

Here's the issue category breakdown:

Category	Count
Complexity	4

View more on Code Climate.

[petqa]

FROM golang:1.22.0-alpine3.19 AS builder

COPY matterbridge /go/src/matterbridge
RUN apk --no-cache add git \
        && go version \
        && cd /go/src/matterbridge \
        && CGO_ENABLED=0 go build -mod vendor -o /bin/matterbridge

FROM alpine:3.19
RUN apk --no-cache add ca-certificates mailcap
COPY --from=builder /bin/matterbridge /bin/matterbridge
RUN mkdir /etc/matterbridge \
  && touch /etc/matterbridge/matterbridge.toml \
  && ln -sf /matterbridge.toml /etc/matterbridge/matterbridge.toml
ENTRYPOINT ["/bin/matterbridge", "-conf", "/etc/matterbridge/matterbridge.toml"]

@kolsys Could you please update the Dockerfile? The current version in the master branch doesn’t work correctly.

[kolsys]

FROM golang:1.22.0-alpine3.19 AS builder

COPY matterbridge /go/src/matterbridge
RUN apk --no-cache add git \
        && go version \
        && cd /go/src/matterbridge \
        && CGO_ENABLED=0 go build -mod vendor -o /bin/matterbridge

FROM alpine:3.19
RUN apk --no-cache add ca-certificates mailcap
COPY --from=builder /bin/matterbridge /bin/matterbridge
RUN mkdir /etc/matterbridge \
  && touch /etc/matterbridge/matterbridge.toml \
  && ln -sf /matterbridge.toml /etc/matterbridge/matterbridge.toml
ENTRYPOINT ["/bin/matterbridge", "-conf", "/etc/matterbridge/matterbridge.toml"]

@kolsys Could you please update the Dockerfile? The current version in the master branch doesn’t work correctly.

Whats wrong with the master version? I've build and run it.

[xeonic-ant]

Hi. We experiencing errors downloading images. Look like the file URL is empty. Bot configured according your recommendations.

config

[api.api]
    BindAddress="0.0.0.0:4242"
    Buffer=1000
    RemoteNickFormat="{NICK}"
[general]
    MediaDownloadPath="/var/www/matterbridge"
    MediaServerDownload="http://matterbridge.matterbridge-namespace/matterbridge"
[slack]
  [slack.one]
    Token="xoxb-*****"
    AppToken="xapp-********"
    PrefixMessagesWithNick=true
    Debug=true
    RemoteNickFormat="[{PROTOCOL}] <{NICK}> "
    PreserveThreading=true
    UseFullName=true
[mattermost]
  [mattermost.two]
    Server="company.com:443"
    Team="team1"
    Token="*****************"
    RemoteNickFormat="[{PROTOCOL}] <{NICK}> "
    PrefixMessagesWithNick=true
    PreserveThreading=true
    UseUserName=true
    Debug=true
[[gateway]]
name="api"
enable=true
[[gateway.inout]]
    account="api.api"
    channel="api"
[[gateway]]
name="client"
enable=true
  [[gateway.inout]]
  account="mattermost.two"
  channel="channel2"
  [[gateway.inout]]
  account="slack.one"
  channel="channel1"

Also tried without MediaDownloadPath/MediaServerDownload options - result is the same.

logs

time="2024-07-12T11:23:12Z" level=debug msg="Message event: {"client_msg_id":"3c60172b-85be-20cb-bed3-1b041bdd51af","type":"message","user":"U05******","text":"test40","thread_ts":"1720779786.805609","ts":"1720783391.651979","channel":"C061W7QFYPM","channel_type":"channel","event_ts":"1720783391.651979","subtype":"file_share","upload":false,"files":[{"id":"F07BZLYLJ6A","created":0,"timestamp":0,"name":"","title":"","mimetype":"","filetype":"png","pretty_type":"","user":"","editable":false,"size":0,"mode":"","is_external":false,"external_type":"","is_public":false,"public_url_shared":false,"display_as_bot":false,"username":"","url_private":"","url_private_download":"","thumb_64":"","thumb_80":"","thumb_360":"","thumb_360_w":0,"thumb_360_h":0,"thumb_480":"","thumb_480_w":0,"thumb_480_h":0,"thumb_160":"","thumb_720":"","thumb_720_w":0,"thumb_720_h":0,"thumb_800":"","thumb_800_w":0,"thumb_800_h":0,"thumb_960":"","thumb_960_w":0,"thumb_960_h":0,"thumb_1024":"","thumb_1024_w":0,"thumb_1024_h":0,"image_exif_rotation":0,"original_w":0,"original_h":0,"permalink":"","permalink_public":""}],"blocks":[{"type":"rich_text","block_id":"o6CuE","elements":[{"type":"rich_text_section","elements":[{"type":"text","text":"test40"}]}]}],"root":null}" func=handleSlackClientSocketMode file="bridge/slack/handlers.go:99" prefix=slack
time="2024-07-12T11:23:12Z" level=debug msg="Trying to download "" with size 0" func=HandleDownloadSize file="bridge/helper/helper.go:162" prefix=slack
time="2024-07-12T11:23:12Z" level=error msg="Could not download incoming file: &errors.errorString{s:"download  failed &url.Error{Op:\"Get\", URL:\"\", Err:(*errors.errorString)(0xc0009131e0)}"}" func=handleAttachments file="bridge/slack/handlers.go:460" prefix=slack

we are running bridge in k8s (without nat) but webockets seems to be work, pings look fine

slack-go/slack/socketmode2024/07/12 12:56:36 socket_mode_managed_conn.go:627: WebSocket ping message received: Ping from applink-13
slack-go/slack/socketmode2024/07/12 12:56:46 socket_mode_managed_conn.go:627: WebSocket ping message received: Ping from applink-13
time="2024-07-12T12:56:52Z" level=debug msg="WsReceiver response: &model.WebSocketResponse{Status:"OK", SeqReply:127, Data:map[string]interface {}{"node_id":"", "server_time":1.720789012475e+12, "text":"pong", "version":"9.2.2"}, Error:(*model.AppError)(nil)}" prefix=matterclient
time="2024-07-12T12:56:52Z" level=debug msg="getting response: &model.WebSocketResponse{Status:"OK", SeqReply:127, Data:map[string]interface {}{"node_id":"", "server_time":1.720789012475e+12, "text":"pong", "version":"9.2.2"}, Error:(*model.AppError)(nil)}" prefix=matterclient

[kolsys]

@xeonic-ant Hi. Looks like the RTM attachment message format is not fully compatible with Event API and it's required to write more complex converter for message than my workaround: https://github.com/42wim/matterbridge/pull/2161/files#diff-014f29c022fd23b8c7f870b5cfa1cb6905ca8a8eb1c83d0209d77d279f4962b9R97

[mfw78]

Just confirming, is there any ability within this using the new slack app to post in a channel within slack using a nickname that isn't the same name as the bot (so as to preserve / bridge the nickname and avatar?)