minitor

A minimal monitoring system

What does it do?

Minitor accepts a YAML configuration file with a set of commands to run and a set of alerts to execute when those commands fail. It is designed to be as simple as possible and relies on other command line tools to do checks and issue alerts.

But why?

I'm running a few small services and found Sensu, Consul, Nagios, etc. to all be far too complicated for my usecase.

So how do I use it?

Running

Install and execute with:

pip install minitor
minitor

If locally developing you can use:

make run

It will read the contents of config.yml and begin its loop. You could also run it directly and provide a new config file via the --config argument.

Docker

You can pull this repository directly from Docker:

docker pull iamthefij/minitor

The Docker image uses a default config.yml that is copied from sample-config.yml. This won't really do anything for you, so when you run the Docker image, you should supply your own config.yml file:

docker run -v $PWD/config.yml:/app/config.yml iamthefij/minitor

Configuring

In this repo, you can explore the sample-config.yml file for an example, but the general structure is as follows. It should be noted that environment variable interpolation happens on load of the YAML file. Also, when alerts are executed, they will be passed through Python's format function with arguments for some attributes of the Monitor. The following monitor specific variables can be referenced using Python formatting syntax:

token	value
{alert_count}	Number of times this monitor has alerted
{alert_message}	The exception message that was raised
{failure_count}	The total number of sequential failed checks for this monitor
{last_output}	The last returned value from the check command to either stderr or stdout
{last_success}	The ISO datetime of the last successful check
{monitor_name}	The name of the monitor that failed and triggered the alert

Metrics

As of v0.3.0, Minitor supports exporting metrics for Prometheus. Prometheus is an open source tool for reading and querying metrics from different sources. Combined with another tool, Grafana, it allows building of charts and dashboards. You could also opt to just use Minitor to log check results, and instead do your alerting with Grafana.

It is also possible to use the metrics endpoint for monitoring Minitor itself! This allows setting up multiple instances of Minitor on different servers and have them monitor each-other so that you can detect a minitor outage.

To run minitor with metrics, use the --metrics (or -m) flag. The metrics will be served on port 8080 by default, though it can be overriden using --metrics-port (or -p)

minitor --metrics
# or
minitor --metrics --metrics-port 3000

Contributing

Whether you're looking to submit a patch or just tell me I broke something, you can contribute through the Github mirror and I can merge PRs back to the source repository.

Primary Repo: https://git.iamthefij.com/iamthefij/minitor.git

Github Mirror: https://github.com/IamTheFij/minitor.git