Migrate to another SMS sending service.

It turns out that Twilio is quite expensive, more than I willing to pay
for this service. So I'm going with MessageBird.

requirements.txt

 dnspython
+messagebird
 requests
-twilio

sms-notify.tf

-variable "twilio_account_sid" {
-  description = "Twilio account SID."
-}
-
-variable "twilio_api_key" {
-  description = "Twilio API key."
-}
-
-variable "twilio_api_secret" {
-  description = "Twilio API secret."
+variable "messagebird_access_key" {
+  description = "MessageBird API access key."
 }
 
 # It would have been nicer to buy the phone number with Terraform and the
@@ -39,11 +31,8 @@ resource "aws_lambda_function" "sms_notify" {
       MODULE             = local.module
       TOPIC_ARN          = local.topic_arn
       VERSION            = local.payload_object_version
-      TWILIO_ACCOUNT_SID = var.twilio_account_sid
-      TWILIO_API_KEY     = var.twilio_api_key
-      TWILIO_API_SECRET  = var.twilio_api_secret
-      TWILIO_FROM_NUMBER = var.twilio_from_number
-      TWILIO_TO_NUMBER   = local.my_phone_number
+      MSGBIRD_ACCESS_KEY = var.messagebird_access_key
+      TO_NUMBER          = local.my_phone_number
     }
   }
 

src/sms_notify.py

 import os
-import twilio.rest  # pylint: disable=import-error
+import messagebird  # pylint: disable=import-error
 
 
-TWILIO_ACCOUNT_SID = os.environ["TWILIO_ACCOUNT_SID"]
-TWILIO_API_KEY = os.environ["TWILIO_API_KEY"]
-TWILIO_API_SECRET = os.environ["TWILIO_API_SECRET"]
-TWILIO_FROM_NUMBER = os.environ["TWILIO_FROM_NUMBER"]
-TWILIO_TO_NUMBER = os.environ["TWILIO_TO_NUMBER"]
+MSGBIRD_ACCESS_KEY = os.environ["MSGBIRD_ACCESS_KEY"]
+TO_NUMBER = os.environ["TO_NUMBER"]
 
 
 # pylint: disable=unused-argument
 def handler(event, context):
     message = event["Records"][0]["Sns"]["Message"]
-    client = twilio.rest.Client(
-        TWILIO_API_KEY, TWILIO_API_SECRET, TWILIO_ACCOUNT_SID
-    )
-    client.messages.create(
-        body=message,
-        from_=TWILIO_FROM_NUMBER,
-        to=TWILIO_TO_NUMBER,
+    client = messagebird.Client(MSGBIRD_ACCESS_KEY)
+    client.messages_create(
+        message,
+        TO_NUMBER,
     )