Java 7 runtime support on App Engine standard was deprecated on December 13, 2017 and will be shut down entirely on January 16, 2019. It is replaced by the Java 8 Runtime Environment.

Samples for the Java 8 runtime can be found here.

This sample demonstrates how to use Twilio on Google App Engine standard environment.

See the sample application documentaion for more detailed instructions.

For more information about Twilio, see their Java quickstart tutorials.

Before you can run or deploy the sample, you will need to do the following:

1. Create a Twilio Account. Google App Engine customers receive a complimentary credit for SMS messages and inbound messages.
2. Create a number on twilio, and configure the voice request URL to be https://your-app-id.appspot.com/call/receive and the SMS request URL to be https://your-app-id.appspot.com/sms/receive.
3. Configure your Twilio settings in the environment variables section in src/main/webapp/WEB-INF/appengine-web.xml.

You can run the application locally to test the callbacks and SMS sending. You will need to set environment variables before starting your application:

$ export TWILIO_ACCOUNT_SID=[your-twilio-accoun-sid]
$ export TWILIO_AUTH_TOKEN=[your-twilio-auth-token]
$ export TWILIO_NUMBER=[your-twilio-number]
$ mvn clean jetty:run