HeartbeatMonitor

HeartbeatMonitor is intended to be used within an internal protected network such as within a Kubernetes cluster and will issue monitor requests to internal services at defined intervals. Successful requests will result in a heartbeat request being issued to a specified url. The current use case for this is to monitor internal services within Kubernetes on the UptimeRobot (https://uptimerobot.com) platform.

Currently only implemented HTTP(s) checking, TCP to follow, and UDP probably a while after that.

The monitor is built as a ruby gem so can be integrated within your application. I have added a CLI however so that you can run from the command line.

bin/monitor --help

will give you the details

These examples were from my first use case and are using the new heartbeat monitor from UptimeRobot, but will perform a HTTP Get request to whatever url you specify.

The following command is the simplest monitor, its testing a http server. By default it is expecting a 200 status response. If it gets this then it will perform a HTTP GET request to the notification url provided.

bin/monitor --type http --test-url http://127.0.0.1 --notification-url https://heartbeat.uptimerobot.com/YOUR_UPTIMEROBOT_MONITOR_ID"]

The following example is performing an HTTP post with some payload to the server under test. As we have specified --test-body-contents it will override the status test above, both can be specified if you need to test both. Refer to --help for the params required.

bin/monitor --type http --test-url http://127.0.0.1:8080/imaginary-post-test --notification-url https://heartbeat.uptimerobot.com/YOUR_UPTIMEROBOT_MONITOR_ID --test-method POST --test-payload '{\"sentence\":{\"subject\":\"John\",\"verb\":\"like\"}}' --test-body-contents 'John likes.'

The following example will test a single page application by opening the url in a headless browser and checking for the existance of a css selector

bin/monitor --type browser --test-url htto://singlepageapp.local/test-page/ --test-browser-selector "#a-valid-id" --notification-url https://heartbeat.uptimerobot.com/YOUR_UPTIMEROBOT_MONITOR_ID

You can run with docker simply run...

docker run -ti stewartmckee/heartbeat_monitor --type http --test-url "http://127.0.0.1:80" --notification-url "https://heartbeat.uptimerobot.com/YOUR_UPTIMEROBOT_MONITOR_ID"

or you can run as a daemon:

docker run -d stewartmckee/heartbeat_monitor --type http --test-url "http://127.0.0.1:80" --notification-url "https://heartbeat.uptimerobot.com/YOUR_UPTIMEROBOT_MONITOR_ID"

The use case this gem was built for was to test services deployed within a kubernetes cluster that are not exposed to the internet. We use an external monitoring service and therefore were unable to directly monitor their uptime.

An example config is available in k8.yaml.

Add this line to your application's Gemfile:

gem 'heartbeat_monitor'

And then execute:

$ bundle

Or install it yourself as:

$ gem install heartbeat_monitor

After checking out the repo, run bin/setup to install dependencies. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Bug reports and pull requests are welcome on GitHub at https://github.com/stewartmckee/heartbeat_monitor.

The gem is available as open source under the terms of the MIT License.