simple-message-blockchain v0.1.0
Purpose
To create a client in javascript of a message-blockchain for experimental and educational purposes. Once version 1 is released and there are a few clients running in the mesh these strings that are written into the blockchain will never be deleted, that's the idea anyway. This project is not intended to be useful, but instead to demonstrate the capabilities of a decentralized additive datastore.
What it is
Decentralized string store with accountability.
Reward: The block to be discovered includes a transaction with "reward" and a public address that is therefore awarded one "messageCoin"
Proof of work: sha256, vulnerable to ASICs I know, enhance your calm, this is a chill project that's intended to be simple.
Difficulty: targeting 60 seconds, adjusts every block based on previous block time
max block size: none yet, but blocks aren't being streamed so the first bottleneck will probably be socketio event size restrictions I'm guessing?
transactions (see transactions section, at the bottom of this readme)
Progress (until v1 assume nothing has been implemented correctly)
-
let people create public&private keys -
let people sign transactions -
define block format(will likely change as this project makes progress towards 1.0.0) -
PoW (sha256 for simplicity) -
difficulty adjustment(https://github.com/Ascendzor/simple-message-blockchain/blob/master/adjustDifficulty.js) -
earn messageCoin -
write message - join peers
-
verify blocks(https://github.com/Ascendzor/simple-message-blockchain/blob/master/blocks.js) - broadcast transactions
- persist blockchain onto fs
- include peers transactions into local block discovery
- handle accidental forks (block solve race condition)
- trade messageCoin
Dependencies
node 6.10.3
How to run:
npm i
node be
CLI commands
blocks -> prints a list of the blocks as your node sees them
block {number} -> prints the details of the specific block
generateKeyPair -> prints newly generated publicKey & privateKey as hex
startMining {publicKey} {privateKey} -> starts mining and creates the reward transaction using the provided pub/priv keys for any block you solve.
stopMining -> stops mining
writeMessage 'the message' {publicKey} {privateKey} -> puts your message into the next block to be discovered
Example:
writeMessage 'something that you want to keep' 042511bb916b3a335125bd3ffd4c8725f9ae8bba5d131148f0c3da10031cea5ab98854fbb4f23f0af0f764450f59efff6744c9e5362ee35461e2e8ff168943cf50 89dde6ac9065a5954340cf04f61ca9c402e80c74ce20c03547d6008e38cd5be0
viewAccount {publicKey} -> prints all details about an account, takes a publicKey. publicKey should be seen as public unique account identifiers.
readall -> prints all messages in the blockchain
Example use cases
How to write "hello world" in this blockchain.
run the client node be and be in the cli mode.
generateKeyPair save publicKey and privateKey on some notepad or something
Using the publicKey and privateKey that you've saved, startMining {publicKey} {privateKey}, this will start rewarding that publicKey account with "messageCoins"
Wait ~15 seconds, to check that everything is ok blocks and there should be a few. All of them mined by you (until I get networking finished).
Now we can write the message writeMessage 'hello world' {publicKey} {privateKey} the message isnt in the blockchain yet, the message is inside the next block to be mined. So keep checking blocks and you should see one of the blocks has two transactions, instead of the normal 1, that second transaction will be your message.
lets read all the messages readall who is the publicKey who wrote the message, what is the message that was written. That's it!
Transactions
There will likely end up being three types of transactions
reward, message, trade
reward rewards the block discoverer with one "messageCoin". reward needs a publicKey and good block.
message will let a user write a message into the blockchain, at the cost of one "messageCoin". message needs a publicKey, messageString, and a signature of the messageString using the privateKey that is associated with the publicKey.
trade will let a user trade messageCoin to other users. trade will require an amount, a fromPublicKey, a toPublicKey, and a signature of all of the above using the privateKey that is connected with the fromPublicKey. trade will be invalidated if the fromPublicKey does not have as much messageCoin as it is trying to trade
What next?
Block format specification and block verification are the keys to creating your own blockchain rules. See https://github.com/Ascendzor/simple-message-blockchain/blob/master/blocks.js for how blocks are specified and verified in this chain.
blockchains are protocols, not code. This is simply the first client for this type of blockchain, if you'd like to contribute to this simple-message-blockchain in your favourite language then go forth and create your own simple-message-blockchain in golang, python, ruby, C#, etc and join the simple-message-blockchain mesh.
Serious stuff and practical applications?
DNS. The rules of this simple-message-blockchain are not constrained enough to be suitable but bear with me. If instead of being rewarded by "messageCoins" you were rewarded with "dnsEntryToken" and owning these tokens gave you authority to set a the value for any key. key: troyswebsite.com, value: 1.2.3.4. You'd need to add a lot of rules and constraints because domain names need to expire and be renewable by the current owner and there's a lot of DNS-specific-logic that needs to be inside the blockFormat and blockVerification. But the advantages are huge:
- Electricity and the internet are the only things you'd need to purchase a domain name, which you have the power to do without asking for any permission or going through a business.
- No one can censor any domain name (think, pirateBay)
- no internet hop to find server ip for dns lookup because it's on the blockchain on your computer already (more privacy)
These are only two examples off the top of my head. I hope more people start to explore the capabilities of decentralized stores