A system developed in a hurry in March 2020 to automate the routing of telephone calls to volunteer workers.

• Multiple volunteer groups are supported.
• Calls are handled by Twilio - the system allows definition of who the call will route to at a given hour.
• Voicemail service can also be provided, with the recording and transcript emailed to a specified email address for a given volunteer group. Sendgrid is used for sending mails.
• Batch email sending to volunteers for the next day, to remind them they have a shift on the phone.
• The system ran on a free Heroku dyno, which is no longer available.

May not be usable in its exact current form, but is open-sourced in case it is of interest (or amusement!) for someone. Specific limitations:

• Not much documentation.
• Not very comprehensive testing.
• Some of the code is not very well-written for readability / maintainability. The main aim was to write the code in such a way as to minimise the chance of making a mistake since I didn't have many tests or much time.
• I had to anonymise / edit some hardcoded details (email addresses etc.) when preparing for open-source. This may not have resulted in consistent names in some places.

The following sections are a verbatim reproduction of notes I kept for myself whilst running and developing the system. They have not been edited for general readability yet.

• python manage.py makemigrations after modifying models
• python manage.py migrate after making migrations

• Backups:
  • heroku pg:backups:capture --app communityline to back up the database
  • heroku pg:backups --app communityline to see backups
  • heroku pg:backups:url <backup number> --app communityline to see backup URL to download
  • See docs for more (link below)
• Change Python version by editing runtime.txt
• Twilio Debugger: https://www.twilio.com/console/debugger
• Deploying to Heroku:
  • git push heroku master
  • The deploy runs the migrations automatically

• Open up anaconda powershell prompt
• Activate villageline environment
• Source env_vars.ps1: . .\env_vars.ps1
• Run heroku local web -f Procfile.windows

• Collection of queries exported into villageline-other
• Call handle URL to use: http://localhost:5000/callrouting/handle
  • Need to create a POST request with the To field populated with the called number
• There are postman saved queries for the recording and transcription hooks too.
  • These need the CallSid which must be "CA..." 34 chars and unique
  • Plus recording URL or transcription status and text as appropriate

• Check volunteer at time: http://localhost:5000/callrouting/volunteers///
  • E.g. https://communityline.herokuapp.com/callrouting/volunteers/1/Monday/17
• Fire up ngrok:
  • ngrok http 5000 in C:\Grahamroot\villageline-other.
  • Copy / paste HTTPS URL into Twilio Webhook URL with /callrouting/handle appended

• Run with python manage.py test <test spec>
• e.g. python manage.py test callrouting.tests.VolunteersViewTests.test_no_shifts

• Getting started on Heroku with Python: https://devcenter.heroku.com/articles/getting-started-with-python
• Getting started sample code: https://github.com/heroku/python-getting-started
• Twilio call forwarding with flask example: https://www.twilio.com/docs/voice/tutorials/call-forwarding-python-flask
• Twilio Programmable Voice Python quickstart (info on using ngrok): https://www.twilio.com/docs/voice/quickstart/python#respond-to-incoming-calls-with-twilio
• TwiML docs (explains the responses and requests): https://www.twilio.com/docs/voice/twiml
  • TwiML recording docs: https://www.twilio.com/docs/voice/twiml/record
  • Getting started with Recording Status Callbacks: https://support.twilio.com/hc/en-us/articles/360014251313-Getting-Started-with-Recording-Status-Callbacks
  • Recording incoming Twilio Voice calls: https://support.twilio.com/hc/en-us/articles/360010317333-Recording-Incoming-Twilio-Voice-Calls
• Django tutorial: https://docs.djangoproject.com/en/3.1/intro/tutorial01/
• Mozilla LocalLibrary tutorial: https://developer.mozilla.org/en-US/docs/Learn/Server-side/Django
  • Testing: https://developer.mozilla.org/en-US/docs/Learn/Server-side/Django/Testing
• Django-twilio docs: https://django-twilio.readthedocs.io/en/latest/
• Deploying Python and Django apps on Heroku: https://devcenter.heroku.com/articles/deploying-python
• Heroku database backups: https://devcenter.heroku.com/articles/heroku-postgres-backups
• Heroku specifying a Python version: https://devcenter.heroku.com/articles/python-runtimes
• Sendgrid - Sending SMTP email with Django: https://sendgrid.com/docs/for-developers/sending-email/django/
• HTML validator: https://validator.w3.org/