Send XMPP messages from the command line

• Author: Solène
• Date: 25 May 2023
• Tags: xmpp monitoring selfhosting reed-alert

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Introduction

As a reed-alert user for monitoring my servers, while using emails works efficiently, I wanted to have more instant notifications for critical issues. I'm also an happy XMPP user, so I looked for a solution to send XMPP messages from a command line.

=> More about reed-alert on the blog | Reed-alert project git repository

I will explain how to use the program go-sendxmpp to send messages from a command line, this is a newer drop-in replacement for the old perl sendxmpp that doesn't seem to work anymore.

=> go-sendxmpp project git repository

Installation

Following go-sendxmpp documentation, you need go to be installed, and then run go install salsa.debian.org/mdosch/go-sendxmpp@latest to compile the binary in ~/go/bin/go-sendxmpp. Because it's a static binary, you can move it to a directory in $PATH.

If I'm satisfied of it, I'll import go-sendxmpp into the OpenBSD ports tree to make it available as a package for everyone.

Configuration

Open a shell with the user that is going to run go-sendxmpp, prepare the configuration file in its default location:

mkdir -p ~/.config/go-sendxmpp
touch ~/.config/go-sendxmpp/config
chmod 400 ~/.config/go-sendxmpp/config

Edit the file ~/.config/go-sendxmpp/config to add the two lines:

username: myuser@myserver
password: hunter2_oryourpassword

Now, your user should be ready to use go-sendxmpp, I recommend always enabling the flag -t to use TLS to connect to the server, but you should really choose an XMPP server providing TLS-only.

The program usage is simple: echo "this is a message for you" | go-sendxmpp dest@remote, and you are done. It's easy to integrate it in shell tasks.

Note that go-sendxmpp allows you to get the password for a command instead of storing it in plain text, this may be more convenient and secure in some scenarios.

Reed-alert configuration

Back to reed-alert, using go-sendxmpp is as easy as declaring a new alert type, especially using the email template:

(alert xmpp "echo -n '[%state%] Problem with %function% %date% %params%' | go-sendxmpp user@remote")

;; example of use
(=> xmpp ping :host "dataswamp.org" :desc "Ping to dataswamp.org")

Conclusion

XMPP is a very reliable communication protocol, I'm happy that I found go-sendxmpp, a modern, working and simple way to programmatically send me alerts using XMPP.