Slack client in bash

slack_client.sh

#!/bin/bash

# https://your-team.slack.com/services/new/incoming-webhook
WEBHOOK_URL=''
CHANNEL='#dev'
USERNAME='sentry'
iCON_URL='https://slack.global.ssl.fastly.net/17635/img/services/sentry_128.png'

function post_message() {
    payload="{'username': '$USERNAME', 'text': '$AT_USER $1', 'channel': '$CHANNEL', 'icon_url': '$ICON_URL'}"
    json=$(echo $payload | sed -e "s/'/\"/g")
    curl -i -H 'Accept: application/json' -H 'Content-Type: application/json' -X POST -d "$json" "$WEBHOOK_URL"
}

if [[ $# -eq 0 ]]; then
    echo "usage: $0 message"
    exit 1
else
    post_message $1
fi