A message was sent to a channel
{
"type": "message",
"subtype": "bot_message",
"ts": "1358877455.000010",
"text": "Pushing is the answer",
"bot_id": "BB12033",
"username": "github",
"icons": {}
}
A bot_message is sent when a message is sent to a channel by an integration "bot". It is like a normal user message, except it has no associated user.
The bot_id tells you which bot sent this message. The username and icon to
use can be looked up by passing this to bots.info. Some bot_messages also include username
and/or icons properties. If present these override the default username or
icon for this bot.