uMonitor

This is a minimalistic python supervisor for your microservices.
Once started, it will launch all the services you've specified in the provided config file, and monitor their execution. Suppose you have following services in the config.json:

{
    "services" : [
        {
            "comment": "Another service to run and monitor.",
            "program" : "python3",
            "args" : ["other_script.py"],
            "persist"  : true,
            "cwd" : "/opt"
        },
        {
            "comment": "And this one should not be restarted",
            "program" : "bash",
            "args" : ["will_be_executed_with_bin_bash.sh"],
            "persist" : false,
            "cwd" : "/opt"
        }
    ]
}

Then the supervisor (uMonitor) will run the specified commands and for those which have persis set, will restart the described processes, whenever they fail/crash.

More complex: it also provides environment variables and venv-like behavior for the specified programs. See the config_example.json for more details.

{
    "comment": "Treat this as virtual environment, but not only for python.",
    "interpreters" : {
        "python3" : "/venv_some/bin/python3",
        "sh" : "/bin/sh",
        "bash" : "/bin/bash"
    },

    "comment": "Services to run and monitor.",
    "services" : [
        {
            "program" : "python3",
            "args" : ["script_1.py"],
            "comment": "Do not recover after crashes",
            "persist" : false,
            "cwd" : "/opt",
            "env" : {
                "PYTHONPATH" : [
                    "/opt/your_python_module/",
                    "/usr/local/another/module/",
                    "/joined_with/colon/will_be"
                ],
                "PATH": [
                    "/opt/prog_1/bin/",
                    "/home/username/.prog_2/bin/",
                    "/joined_with/colon/will_be"
                ],
                "ENVIRON_VARIABLE": [
                    "SINGLE_VALUE_42"
                ]
            }
        },
        {
            "comment": "Another service to run and monitor.",
            "program" : "python3",
            "args" : ["other_script.py"],
            "persist"  : true,
            "cwd" : "/opt"
        },
        {
            "comment": "And this one should not be restarted",
            "program" : "bash",
            "args" : ["will_be_executed_with_bin_bash.sh"],
            "persist" : false,
            "cwd" : "/opt"
        }
    ]
}

Installation:

• Installation using pip:

python3 -m pip install umonitor

• Installation using poetry:

poetry add umonitor

Usage example:

• As a callable module:

python3 -m umonitor config.json

• In a script:

import umonitor

monitor = umonitor.uMonitor("config.json")
monitor.run()