Udacity Project 4: Flight Surety

Description:

FlightSurety is a sample application project for Udacity's Blockchain course. This app demontstrates several approaches used in dapp development. Separation of concerns: separate state of dapp and business logic into different contracts. Oracle: gateway into real world. Roles, operational status control and multi-part consensus.

Purposes:

Flight Surety is flight delay insurance for passengers
Managed as collaboration between multiple airlines
Passengers purchase insurance prior to flight
If flight is delayed due to airline fault, passengers are paid 1.5X the amount the paid for the insurance
Oracles provide information flight status information

Project Requirements:

1. Separation of Concerns.

FlightSuretyData contract for data persistence
FlightSuretyApp for app logic and oracles code
Dapp client for triggering contract calls
Server app for simulating Oracles

2. Oracles.

Oracles are implemented as a server app
Upon startup, upon 20+ oracles are registered and their assigned indexes are persisted in memory
Client Dapp is used to trigger request to update flight status generation OracleRequest event that is captured by server
Server will loop through all registered oracles,identify those oracles for which the request applies, and respond by calling into app logic contract with the appropriate status code

3. Airlines.

Register first airline when contract is deployed
Only existing airline can register a new airline until there at least four airlines registered
Registration of fifth and subsequent airlines requires multy-part consensus of 50% registered airlines
Airline can be registered, but does not participated until it submits funding of 10 ether

4. Passengers.

Passenger may pay up to 1 ether for purchasing flight insurance
Flight numbers and timestamp are fixed for the purpose of the project and can be defined in the Dapp client
If flight is delayed due to airline fault, passenger receives credit of 1.5X the amount they paid
Funds are transfered from to the passenger wallet only when they initiate withdraw

5. General.

Contracts must have operational status control
Functions must fail fast
Scaffolding code is provided but you are free to replace it with your own code
Have fun learning!

Project Structure:

Smart contracts in ./ethereum
Server applications as Oracles in ./server
Dapp webapp in ./web-app

How to run:

Launch app
npm i - install dependencies
npm run ganache:dev - start ganache testnet
npm run migrate:dev - compile and deploy contracts to testnet
npm run dapp - launch web dapp
npm run server - run oracle servers in background. Don't forget stop them!
Launch dapp in the browser on http://localhost:8000
Create test flights, click on Register button
Choose flight and buy insurance
Submit to oracles the flight
Try payout your money if flight was not in time
Withdraw your ether

niallkh / flightsurety