I need to send a message in slack at a time set in advance.
Is there a way to do it through the Slack API or do I need to have a script running and checking if it's time to send the message and then send it?
You should be able to create a reminder sending a message to @slackbot The message should be like:
/remind [@someone or #channel] [what] [when]
Here's some examples:
/remind @username to do something in 24 hours
or:
/remind @username to do something at 16:00