tor-uptime-monitor

A small (30MB!) Docker image based on osminogin/tor-simple, configured with environment variables, which checks to see if a Tor site is online and pings a (clearnet) uptime monitor if so. This was intended to be a one-stop-shop to increase assurance that my Tor site is up, connecting Tor uptime to monitors that have the ability to remind me via emails/texts/etc.

Tor is bundled in this Docker image and controlled via stem! It's completely hands-free and works natively in plain old Docker. Whenever the URL can't be accessed over Tor, instead of failing immediately it'll also request a new identity via sending NEWNYM to the Tor control port, which can help move the monitor to a better-functioning circuit.

Example Usage

$ docker run --detach \
    --name tor-uptime-monitor \
    --restart=always \
    -e MONITOR_TOR_URL=http://tweedge32j4ib2hrj57l676twj2rwedkkkbr57xcz5z73vpkolws6vid.onion/ \
    -e UPTIME_REPORT_URL=https://ping.ohdear.app/aaaaaaaa-bbbb-cccc-dddd-eeeeeeeeeeee \
    tweedge/tor-uptime-monitor

Configuration

Two environment variables must be set (and the container will stop if these are missing):

• MONITOR_TOR_URL is the URL that you want to access on Tor, ex. your Onion site
• UPTIME_REPORT_URL is the URL what you want to access whenn (and only when) your Tor site was successfully accessed

The following environment variables are available to configure your monitor's behavior:

• MONITOR_TOR_CONTENTS [HIGHLY RECOMMENDED] is a string that must be present in the body of the URL you're checking on Tor, to ensure your site is truly up and not returning an error (default: don't check for any text)
• MONITOR_TOR_TIMEOUT configures the request timeout (in seconds) while fetching the URL you're checking via Tor (default: 30)
• MONITOR_SLEEP configures how long (in seconds) to sleep between attempts to access the URL on Tor (default: 30)

And if you're a real nerd, you can also tweak these probably-OK-to-leave-at-default variables:

• PRINT_TOR_MESSAGES configures what messages you want to see from Tor. Currently this has one option: bootstrap_only (which is the default) will only print bootstrapping messages so you can see if Tor comes up. Setting this to anything else will print all messages from Tor.
• RESTART_AFTER_X_FAILURES configures how many consecutive failures to tolerate before exiting this script, which if you've set the Docker restart policy to "always," prompts creation of a new container (default: 5)
• UPTIME_REPORT_RESPONSE_CODE_UNDER configures when to show a warning in the logs if a the uptime reporting URL gave an unexpectedly high response code (default: 300 - i.e. any sub-300 response code is OK and won't show a warning)