Photography by on Ales Nesetril Unsplash I’m a big fan of automating repetitive tasks and I always try to automate everything I can. Remember the ? I try to do some similar stuff too! Imagine the following scenario: everytime that you close your MacBook Pro lid it sends a message, telling your team that you’re gone for the day. In this article, I’m going to show how to do this! guy that automated part of his job In order to send messages on , you’ll need a . To get one you need to create a new app, install in your workspace, go to OAuth & Permissions and copy your generated Slack Slack Access Token Slack OAuth Access Token. To be able to execute scripts when your Mac goes to sleep or wakes up we’ll use ’s 2.2. After you download the file, unpack it and open a new Terminal window on its directory and type the following: Bernhard Baehr SleepWatcher $ sudo mkdir -p /usr/local/sbin /usr/local/share/man/man8 $ sudo cp sleepwatcher /usr/local/sbin $ sudo cp sleepwatcher.8 /usr/local/share/man/man8 In this article I’m just going to write about the event trigger. If you want to know about more events or read the documentation just type: sleep $ man sleepwatcher Now that is in the correct place you can try the script that’s going to be executed with the following command: SleepWatcher $ /usr/local/sbin/sleepwatcher --verbose --sleep /path/to/your/sleepscript After you’re finished with the tests and everything behaves as expected is time to setup to run as a daemon. To do this you can type the following commands: SleepWatcher $ sudo cp config/de.bernhard-baehr.sleepwatcher-20compatibility.plist /Library/LaunchDaemons/de.bernhard-baehr.sleepwatcher.plist$ sudo cp config/rc.* /usr/local/bin After that just execute to start your daemon. $ sudo launchctl load /Library/LaunchDaemons/de.bernhard-baehr.sleepwatcher.plist Now that everything is ready you need to write the script that’s going to be executed everytime your computer goes to sleep. We’re calling it and make it executable: .sleep $ touch ~/.sleep$ chmod +x ~/.sleep In this file, we’re going to place the code that’s going to be used to post our messages to . Mine looks like: Slack #!/bin/bash STARTING_TIME="17:00" ENDING_TIME="19:00" CURRENT_TIME=$(date +%H:%M) CURRENT_DATE=$(date "+%d/%m/%Y") READ_DATE=$(cat ~/.say_message.lock) if [[ "$CURRENT_TIME" > "$STARTING_TIME" ]] && [[ "$CURRENT_TIME" < "$ENDING_TIME" ]] && [[ "$READ_DATE" < "$CURRENT_DATE" ]]; then TOKEN=xoxp-2… CHANNEL=#channel\_name declare -a EXPRESSIONS=("Write" "Your" "Expressions" "Here") SELECTED\_EXPRESSION=${EXPRESSIONS\[$RANDOM % ${#EXPRESSIONS\[@\]} \]} curl -X POST \\ --connect-timeout 10 \\ --max-time 10 \\ --retry 10 \\ --retry-delay 0 \\ --retry-max-time 60 \\ --'content-type: multipart/form-data' \\ -F token=$TOKEN \\ -F "channel=$CHANNEL" \\ -F text="$SELECTED\_EXPRESSION" \\ -F as\_user=true \\ [https://slack.com/api/chat.postMessage](https://slack.com/api/chat.postMessage) echo $CURRENT\_DATE > ~/.say\_message.lock fi Let me explain the script line by line. Script explanation I’m using the following variables to specify that the message is meant to be sent only between 17:00 and 19:00 STARTING_TIME="17:00" ENDING_TIME="19:00" These are used to ensure that the message is only sent once per day, to prevent sending it multiple every time that you lock your computer, for instance. CURRENT_TIME=$(date +%H:%M) CURRENT_DATE=$(date "+%d/%m/%Y") READ_DATE=$(cat ~/.say_message.lock) The condition bellow allows me to ensure that the conditions I’ve specified above are met. Which are: the message is only sent between 17:00 and 19:00 and only executes once per day. if if [[ "$CURRENT_TIME" > "$STARTING_TIME" ]] && [[ "$CURRENT_TIME" < "$ENDING_TIME" ]] && [[ "$READ_DATE" < "$CURRENT_DATE" ]]; then fi In order to send the message to the desired channel you have to specify the token you got from and the channel to post the message. I also have an array of expressions to be randomized later. This is meant to send a different message. To achieve this I have the following lines: Slack TOKEN=xoxp-2[…] CHANNEL=#channel_name declare -a EXPRESSIONS=("Write" "Your" "Expressions" "Here") SELECTED_EXPRESSION=${EXPRESSIONS[$RANDOM % ${#EXPRESSIONS[@]} ]} When everything is set we need to send our message to . This is done using . These are my configs: Slack API cURL curl -X POST \ --connect-timeout 10 \ --max-time 10 \ --retry 10 \ --retry-delay 0 \ --retry-max-time 60 \ --'content-type: multipart/form-data' \ -F token=$TOKEN \ -F "channel=$CHANNEL" \ -F text="$SELECTED_EXPRESSION" \ -F as_user=true \ https://slack.com/api/chat.postMessage I’m telling to: cURL Each attempt last 10 seconds with --max-time 10 Retry 10 times using --retry 10 Disable cURL sleep between retries using --retry-delay 0 Wait 60 seconds max using --retry-max-time 60 The code above will send a POST request to with the specified payload. You can check more about endpoint reading Slack . https://slack.com/api/chat.postMessage postMessage documentation After the execution of the request I’m updating the “lock” file with the new date with the line: echo $CURRENT_DATE > ~/.say_message.lock This is meant to ensure that only one message per day is sent. This is how I automated my interactions with Slack. Let me know your thoughts on this using the comments bellow.
