"When hosted monitoring is either too expensive or too complicated."

Say you have a hundred or more websites and you want to receive a Slack notification when one of them goes down; and another notification when it comes back up.

Website Monitor does exactly this, and is configured by a single YAML file.

If you are flush with both cash and patience, you might want to skip this and head on over to site24x7.com. Otherwise, read on.

Website monitor checks two things. First, it checks that the status code of the GET request is 200. Second, it checks that the expected_text that you specified in the YAML file is contained in the returned html.

• Python 3.6 or later (because f-strings)
• Read/Write access to the observations/ directory.

git clone git@github.com:jackdesert/website-monitor
cd website-monitor
pyenv local 3.6.6 # Choose any version 3.6 or later
python -m pip install bs4 pyyaml lxml

Make a config file:

cd website-monitor/config
cp sites.yml-EXAMPLE sites.yml
vi sites.yml

Change the webhook_url to one provided by Slack.

Remove the example sites and enter your own sites. For each site, be sure to put a word or phrase that Website Monitor should expect in the body of the response.

cd website-monitor
env/bin/python monitor/models/website_monitor.py

Once you have this up and running, you will probably want to set it up to run as a daemon. A systemd unit file is provided.

cd /lib/systemd/system
sudo ln -s /path/to/site-monitor/config/site-monitor.service
sudo systemctl enable site-monitor.service
sudo systemctl start site-monitor.service

cd website-monitor
env/bin/pytest

• Simple web page that shows the current status of all the monitors
  • green on the left; red on the right
• Only allow one thread to print to screen at a time.
• Fix so that messages written to the system journal show up immediately, instead of delayed and all in a group

• Include status code with DOWN messages
• Included any exceptions raised with DOWN messages monitor =======

• Change directory into your newly created project.

  cd website-monitor

• Create a Python virtual environment.

  python3 -m venv env

• Upgrade packaging tools.

  env/bin/pip install --upgrade pip setuptools requests pyaml mock lxml

• Install the project in editable mode with its testing requirements.

  env/bin/pip install -e ".[testing]"

• Run your project's tests.

  env/bin/pytest

• Run your project.

  env/bin/pserve development.ini