README.md

BlockTrack

Blockchain based inventory tracking. Because we need to keep track of our iPhone chargers! A quick blockchain app I created for AlephSummit2018.

Getting Started

1. npm i

2. node app.js

3. Navigate to https://localhost:3001 for the client app.

4. Current state of the blockchain app is at https://localhost:3000/state (Note the port is 3000 not 3001)

5. To create a transaction send a POST to https://localhost:3000/txs with the following format:

   {
     "item": "iPhone charger",
     "user": "John Doe"
   }

Local Development

• node app.js --dev

In this mode lotion will not attempt to connect to any peers and the blockchain will be cleared on every run. This is convenient for development because you get a fresh blockchain on every run and will not screw up the existing chain running on other nodes.

All this app does is:

1. Start with initial state:

   {}

2. Accept transactions of the form:

   {
     "item": "iPhone",
     "user": "John Doe"
   }

3. Which will mutate state into:

   {
     "items": {
       "iPhone": "John Doe"
     },
     "users": {
       "John Doe": {
           "iPhone": true
       }
     }
   }

4. Here's another transaction:

   {
     "item": "Macbook",
     "user": "Jane Doe"
   }

5. Which will mutate state into:

   {
     "items": {
       "iPhone": "John Doe",
       "Macbook": "Jane Doe"
     },
     "users": {
       "John Doe": {
           "iPhone": true
       },
       "Jane Doe": {
           "Macbook": true
       }
     }
   }

6. Here's another transaction where Jane takes the iPhone from John:

   {
     "item": "iPhone",
     "user": "Jane Doe"
   }

7. You will end up with the following state:

   {
     "items": {
       "iPhone": "Jane Doe",
       "Macbook": "Jane Doe"
     },
     "users": {
       "Jane Doe": {
           "iPhone": true,
           "Macbook": true
       }
     }
   }

That's it!