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group_join message event

A member joined a group

Compatibility: RTM


{
    "type": "message",
    "subtype": "group_join",
    "ts": "1358877458.000011",
    "user": "U2147483828",
    "text": "<@U2147483828|cal> has joined the group"
}

A group_join message is sent when a member joins a private group.

If the user was invited, the message will include an inviter property containing the user ID of the inviting user.