COVID-Watch Cloud Functions

This repo contains code which is used in the Firebase project to control the Firestore security rules, and define cloud functions.

TODO

• TypeScript Build System
• Initial Test Suite
• Validate Survey Data
• Initial Survey Endpoint
• Write to Firestore
• Add watcher to auto build .ts to .js
• Agree on API / Response Payloads
• Verify Cryptographic Hashes
• Cache Reads in Buckets

Setup

• VSCode
• Prettier Code Formatter
• Node 10+
• Firestore CLI
• Postman

Security Model

The idea is to set reads to be open and public as all data is inherently anonymous. Writes are set to disabled except through a cloud endpoint which does the job validating the cryptographic signatures are valid before writing to the firestore.

See the TCN implementation here: https://github.com/TCNCoalition/TCN

NPM Install

$ cd functions
$ npm install

Run Firestore Emulators

Run with debug logging enabled to see console.logs

$ DEBUG_LOGGING=1; firebase emulators:start

Run Tests

$ cd functions
$ npm test

Firebase Functions

TypeScript + Babel

We are using TypeScript and Babel to convert to JS which will run on Node 10 and the Firebase Emulator.

Build

To convert the .ts files in src into .js files in lib run:

$ npm run-script build

The emulator should hot reload the scripts.

Local Endpoints

You can hit the endpoints with curl or Postman.

http://localhost:5001/tagstwo-431e3/us-central1/submitReport

Example Report JSON Payload:

{
  "temporary_contact_key_bytes": "PvLGpfQZgGqnoQRtSr0AHd8J5/WdKwaJNLRCkhGlgHU=",
  "memo_data": "SGVsbG8sIFdvcmxkIQ==",
  "memo_type": 1,
  "start_index": 1,
  "end_index": 8,
  "signature_bytes": "+k7HDsVZPY5Pxcz0cpwVBvDOHrrQ0+AyDVL/MbGkXBYG2WAyoqLaNxFuXiB9rSzkdCesDv1NSSk06hrjx2YABA==",
  "report_verification_public_key_bytes": "v78liBBYQrFXqOH6YydUD1aGpXLMgruKATAjFZ0ycLk="
}

Firestore Emulator REST API

You can query the Firestore API with urls like this: http://localhost:8080/v1/projects/tagstwo-431e3/databases/(default)/documents/signed_reports

$ curl --location --request GET 'http://localhost:8080/v1/projects/tagstwo-431e3/databases/(default)/documents/signed_reports'

Postman Collection

You can import the COVID-Watch.postman_collection.json to play with the local Cloud Functions and Firestore Emulator.

Deployment

Cloud Functions

Deploy a single function:

$ firebase deploy --only functions:submitReport

Live URLS

https://us-central1-tagstwo-431e3.cloudfunctions.net/submitReport