Blockly in OH3 makes it easy to develop basic rules. I have several rules that notify me of events via the OpenHAB mobile app. For some events, I also wanted to generate email notifications so I could expand the range of people getting alerts. The Mail Binding seemed overkill since I had already configured Linux mail when I set up the openhabian server and I could not figure out how to use the Mail Binding from Blockly.
I created mailOHalert.sh in /home/openhabian and made it executable. All arguments are sent in the body of the email to one or more target emails addresses.
#!/bin/sh
echo "$@" | mail -s "OpenHAB Alert" "email1@domain1 <,email2@domain2>"
I added the script to /etc/openhab/misc/exec.whitelist:
# For security reasons all commands that are used by the exec binding or transformation need to be whitelisted.
# Every command needs to be listed on a separate line below.
/home/openhabian/mailOHalert.sh %2$s
I installed the Exec Binding and also the RegEx Transformation. Using the Main UI, I defined a Thing, provided a descriptive name, and set the Command to the fully qualified script name:
/home/openhabian/mailOHalert.sh %2$s
This automatically created five Channels: Output, Input, Exit Value, Running, Last Execution. I used “Add Equipment to Model” for later access.
Calling mailOHalert.sh from Blockly involves setting Input and Running:
The double-quotes around the Input argument prevents Linux syntax errors if the argument contains characters like parentheses.
