Beacon coin

Beacon coin is a Chia singelton coin that can store data that needs to be:

• always available
• censorship resistant
• versioned
• potentially immutable

You might want to use it for coordinating peers in a network, storing DNS information or whatever else you think of. (please share though). I wrote this mainly to learn more about Chialisp and explore smart coins in Chia Network (especially singletons). I used some general principles that could be expanded to implement a smart contract type of coin, with methods and state etc.

This code is still work in progress so please DO NOT USE it on mainnet. Use at your own risk.

Please note that I'm not affiliated with Chia Network. This means that I don't know if this is the right way to write smart coins and that it might contain some serious security issues until more people review it. Any feedback appreciated. Thanks!

How to use

For Unix/Macs

Clone this repo in a directory.

python3 -m venv venv
. ./venv/bin/activate
pip install .
beacon-coin --help

It should work on Windows too, although did't test:

py -m venv venv
./venv/Scripts/activate
pip install .
beacon-coin

You'll need a testnet chia node and wallet with some mojos. Once wallet and node are synced, you can start using beacon coin. Make sure CHIA_ROOT is set and pointing to the correct chia network (testnet!). More on that here: https://github.com/Chia-Network/chia-blockchain/wiki/How-to-connect-to-the-Testnet

Usage

Usage: beacon-coin [OPTIONS] COMMAND [ARGS]...

  Manage beacon coins on Chia network.

  They can be used to store key information in a decentralized and durable
  way.

Options:
  --config-path TEXT  Path to your Chia blockchain config (usually ~/.chia).
                      Defaults to fetching it from CHIA_ROOT env var.

  --fingerprint TEXT  Key fingerprint, will default to first one it finds if
                      not provided.

  -v, --verbose       Show more debugging info.
  --help              Show this message and exit.

Commands:
  add-pair      Add a pair of strings to coin data.
  change-owner  Change the owner, works on mutable and immutable coins.
  freeze        Freezing makes the coin immutable
  get-data      Returns a JSON of coin data and metadata Can be piped into...
  mint          Mint a new beacon coin, returns a LAUNCHER_ID.
  remove-pair   Remove a pair at a specifed index from coin data.

First you'll need to mint a beacon coin:

$ beacon-coin mint --fee=10 
Minted a new beacon coin with id: 3085341ed92faeda6887f5270b7cc049c024bd2bf1c27a9e8f33e1f902fbea12

Track transaction: 070d0ed91de0ce80c884f13ecad4db02d9d63ae028244e1e55dc69aac1b7904f     Fee: 10 mojos

NOTE: Store launcher_id somewhere safe as this wallet doesn't keep it anywhere yet.

Wait until transaction is processed.

You can use cdv mempool -txid 070d0ed91de0ce80c884f13ecad4db02d9d63ae028244e1e55dc69aac1b7904f

Let's check contents first:

$ beacon-coin get-data 0x3085341ed92faeda6887f5270b7cc049c024bd2bf1c27a9e8f33e1f902fbea12
{"version": 1, "data": []}

Ok, now let's add some data:

$ beacon-coin add-pair --fee=10 0x3085341ed92faeda6887f5270b7cc049c024bd2bf1c27a9e8f33e1f902fbea12 "some" "data"
Added pair ('some', 'data') using transaction: 364eeab9433f6bbf382f2659bdf5bc23c51ae862a765b3d3fdfcf56fe9c8bf1e

Wait again for node to process it.

And let's check content again:

$ beacon-coin get-data 0x3085341ed92faeda6887f5270b7cc049c024bd2bf1c27a9e8f33e1f902fbea12                       
{"version": 2, "data": [[0, ["some", "data"]]]}

Ok, we just stored some data on Chia blockchain.

Let's add more and test the removal.

$ beacon-coin add-pair --fee=10 0x3085341ed92faeda6887f5270b7cc049c024bd2bf1c27a9e8f33e1f902fbea12 "more" "data"
Added pair ('more', 'data') using transaction: 4e1ed3b76c474a73d68781d328b130d408bacd6650b4018d63231581655aac33

$ beacon-coin get-data 0x3085341ed92faeda6887f5270b7cc049c024bd2bf1c27a9e8f33e1f902fbea12                       
{"version": 3, "data": [[0, ["more", "data"]], [1, ["some", "data"]]]}

$ beacon-coin remove-pair --fee=15 0x3085341ed92faeda6887f5270b7cc049c024bd2bf1c27a9e8f33e1f902fbea12 0
Removed pair at 0 using transaction: efbbe9fbeadc78c0840f3bffbda57ea1f8d734cbb634992fcd5e4aa28c4a5ab1

$ beacon-coin get-data 0x3085341ed92faeda6887f5270b7cc049c024bd2bf1c27a9e8f33e1f902fbea12
{"version": 4, "data": [[0, ["some", "data"]]]}

Python API

beacon-coin is internally using python API to manage coins.

TODOs

• refactor wallet and make it more DRY
• publish tests (right now still in progress)
• add soft linking between different coins, can enable things like having an immutable beacon coin that points to other mutable coins