import qualified Web.Slack.Auth as Auth
slackSecret = Auth.SlackSigningToken "8f742231b10e8888abcd99yyyzzz85a5"
timestamp = Auth.Timestamp 1531420618
body = "token=xyzz0WbapA4vBCDEFasx0q6G&team_id=T1DC2JH3J&team_domain=testteamnow&channel_id=G8PSS9T3V&channel_name=foobar&user_id=U2CERLKJA&user_name=roadrunner&command=%2Fwebhook-collect&text=&response_url=https%3A%2F%2Fhooks.slack.com%2Fcommands%2FT1DC2JH3J%2F397700885554%2F96rGlfmibIGlgcZRskXaIFfN&trigger_id=398738663015.47445629121.803a0bc887a14d10d2c447fce8b6703c"
expectedHash = Auth.Hex "v0=a2114d57b48eac39b9ad189dd8316235a7b4a8d21a10bd27519666489c69b503"
Auth.verify slackSecret timestamp body expectedHash