The sms channel uses Twilio. Twilio posts inbound SMS and MMS to Habakkuk's HTTP server, signed with the account's auth token; replies go out through Twilio's Messages API.

Note

SMS is a webhook channel: Twilio must reach habakkuk serve over the internet, so you need an http section with a public_url.

Set it up#

In Twilio, buy or pick a number that can send and receive SMS (and MMS, for media).
Set the number's A message comes in webhook (HTTP POST) to <public_url>/channels/<name>, for example https://habakkuk.example.com/channels/sms. habakkuk doctor prints the URL.
Put the auth token in .env and configure the channel:

yaml

channels:
  sms:
    type: sms
    allow_from: ["15557654321"]            # numbers without +
    sms:
      account_sid: ACxxxxxxxx
      auth_token_env: TWILIO_AUTH_TOKEN
      from: "+15551234567"                 # or messaging_service_sid: MGxxxxxxxx
http:
  listen: 127.0.0.1:8484
  public_url: https://habakkuk.example.com

Use messaging_service_sid instead of from if you send through a Twilio messaging service.

Important

Twilio signs the exact URL it calls. public_url must match the webhook URL in Twilio character for character, or every request is refused.

Access#

allow_from takes phone numbers without the +. Anyone else who texts gets a pairing code.

What works#

SMS and MMS media in; SMS and MMS out, with media up to 5 MB. Twilio fetches outgoing media from a one-hour URL on Habakkuk's server.
No typing indicator or buttons: approvals are answered by texting yes or no.

Troubleshooting#

Symptom	Cause and fix
Texts never arrive	Check the webhook URL in Twilio, that `public_url` matches it exactly, and that the proxy or tunnel reaches `listen`.
Media is not delivered	The file is over 5 MB, or Twilio cannot reach `public_url` to fetch it.