midcheck

Simple NodeJS program to notify clients by SMS when certain conditions are met on a web page's source content.

Installation & Execution

First: you'll need an activated Twilio account. Free trial works OK.

Then:

git clone https://github.com/tomtwo/midcheck
cd midcheck && npm install
# Configure package.json with Twilio API credentials and target SMS number
# Modify app.js to include your checks
npm start

It's recommended to background this process, so that it can continuously keep checking. For example, you may use nohup:

nohup npm start &

Configuration

env

Sensitive config is passed in via env:

  TWILIO_ACCOUNT_SID=<your twilio sid>
  TWILIO_AUTH_TOKEN=<your twilio auth token>
  TWILIO_PHONE_NUMBER=<your twilio phone number>
  DESTINATION_NUMBER=<phone number to notify>

Alternatively, put the above in a .env file to pass environment variables in via dotenv.

package.json

In package.json, you can configure app's configuration:

  "config": {
    "checkIntervalSeconds": <INTERVAL IN SECONDS TO CHECK PAGES>
  }

app.js

In app.js, the main app's logic is contained. You must add checks by calling checker.addCheck():

checker.addCheck("SYSTEM007", 
                 "http://www.wearesystem.co.uk/product/systm007-las-backyard-tic", 
                 function(page) {

    // Return true iff "Coming Soon" is not present
    return !(/(Coming Soon)/.test(page));

});

Arguments:

name (string): A name for the check, which is quoted when users are notified
url (string): The URL for which to perform the check on
callback(page) (function): Callback which to perform your synchronous analysis of the page, returning true when the client should be alerted

Documentation for internal objects

No public API is available (yet), please do not depend on any of this for external projects. Fork or use as given.

License

MIT

Future work

Currently this project is fairly flexible for basic use cases. In future, all synchronous calls should probably be removed - it's not the NodeJS way!

Also, I'm not sure about the current configuration split between package.json and app.js. I may move more app logic out of app.js and move the configuration in from package.json.

## midcheck?!

Midnight Checker

tomtwo / midcheck