Datacraft-GaaS / b4ll-callcentre

Biometrics In Low-Tech environments - Voice Asset

Account Management PoC using Voice Biometrics

Part of the Biometrics In Low-Tech Environments project

• Account Management PoC using Voice Biometrics
  • Part of the Biometrics In Low-Tech Environments project
  • Setup Guide
    • Development Dependencies
    • Project Setup
  • Development
    • Running Locally
    • Handlers
    • Testing
  • Deployment
  • Twilio Setup
  • Troubleshooting
    • Error: EACCES: permission denied, open '{...}/dist/handlers/{someFunction}/index.js
    • The security token included in the request is invalid.
    • Missing credentials in config, if using AWS_CONFIG_FILE, set AWS_SDK_LOAD_CONFIG=1
    • Lambda responded with undefined status code or index.get is undefined or not exported

Setup Guide

Development Dependencies

Before proceeding, please ensure the following are installed on your development machine:

• Node
• Git
• Yarn Classic (optional, recommended)
• AWS CLI
• Docker
• Docker Compose
• AWS SAM

Project Setup

1. Checkout the project code locally
2. Run yarn to install project dependencies
3. Check the .env file to update any values specific to your environment (e.g. AWS_PROFILE)

Development

Running Locally

• Run yarn dev to watch for file changes and start a fast local server

• Run yarn dev:clean to remove any conflicting containers from a previous session

  If necessary, run aws config to insert your information.

Handlers

Documentation for handlers can be found here

Testing

Documentation for tests can be found here

Deployment

Deployment information can be found here

Twilio Setup

1. Buy a virtual phone number on Twilio If you are in the trial account and if it is necessary, release your current trial number: https://www.twilio.com/console/phone-numbers/incoming Then, buy a local number using the same link.
2. Obtain webhook URL
   • If local development, start the server then use ngrok to make it globally accessible (npx ngrok http 3000)
   • If deployed version, copy the API server url from the CloudFormation Output
3. Change the "A Call Comes In" webhook URL on the Twilio dashboard for your Webhook URL
4. Select HTTP GET method
5. Dial the virtual number and test your application

Troubleshooting

Error: EACCES: permission denied, open '{...}/dist/handlers/{someFunction}/index.js

This error sometimes occurs when running yarn dev. The command does two things: creates some docker containers to run our functions, and starts webpack in watch mode to compile our code. Ideally, webpack compiles the code first to create the correct directory structure. Sometimes though, the docker containers are created first, and they implicitly create a volume (owned by root) where our code should go. To resolve this, you can chown -R the dist directory to give webpack permission to write there again.

The security token included in the request is invalid.

This is an error normally caused when a function can't find the DynamoDB table. Generally this is caused when the TABLE_NAME variable is incorrectly set - check dev/envVars.json to ensure your function is receiving it correctly.

Missing credentials in config, if using AWS_CONFIG_FILE, set AWS_SDK_LOAD_CONFIG=1

The AWS SDK is unable to authenticate you. This is normally caused by a similar error as above (TABLE_NAME incorrectly set). Add AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY and AWS_REGION to dev/envVars.json for your function.

Lambda responded with undefined status code or index.get is undefined or not exported

This is normally a sign that the lambda function has not been built correctly. Try running yarn build before yarn dev again. This will often be related to the Error: EACCES: permission denied error above.