gochain

gochain is a proof-of-work blockchain written in go.

Features

• Proof-Of-Work
• Persistence
• CLI
• Transactions
• Addresses
• Merkle Tree
• Network

How to run the gochain network

First, set NODE_ID to 3000 (export NODE_ID=3000) in the first terminal window. Create a wallet and a new blockchain on the NODE 3000 terminal:

$ go run .createblockchain -address <address3000>

After that, the blockchain will contain only the genesis block. We need to save the block and use it in other nodes.

$ cp blockchain_3000.db blockchain_genesis.db 

Next, open a the terminal window of your second Node and set node ID to 3001. This will be a wallet node. Generate some addresses with go run .createwallet.

Back to the first window send some coins to the wallet addresses:

$ go run . send -from <address3000> -to <address3001> -amount 10 -mine

-mine flag means that the block will be immediately mined by the same node.

Start the node:

$ go run . startnode

The node must be running until the end of the scenario.

Start the blockchain of NODE 3001 with the genesis block saved above:

$ cp blockchain_genesis.db blockchain_3001.db

Run the node:

$ go run . startnode

It'll download all the blocks from the 3000 node. To check that everything's ok, stop the node and check the balances:

$ go run . getbalance -address <address3001>
Balance of '<address3001>': 10

Also, you can check the balance of the NODE 3000 address, because the node 3001 now has its blockchain:

$ go run . getbalance -address <address3000>
Balance of '<address3000>': 10

Open a new terminal window and set its ID to 3002, and generate a wallet. This will be a miner node. Initialize the blockchain:

$ cp blockchain_genesis.db blockchain_3002.db

And start the node:

$ go run . startnode -miner <address3002>

Send some coins from NODE 3001:

$ go run . send -from <address3001> -to <address3002> -amount 1
$ go run . send -from <address3001> -to <address3000> -amount 1

Quickly! Switch to the miner node 3002 and see it mining a new block! Also, check the output of the central node.

Switch to the node 3001 and start it:

$ go run . startnode

It'll download the newly mined block!

Stop it and check balances:

$ go run . getbalance -address <address3001>
Balance of 'WALLET_1': 8

Research and ToDos

• Target Adjusting Algorithm
• Sharding
• Test other consensus methods
• Block Explorer (Web)

Ressources

• Blockchain für Entwickler

Contact

• Email: [email protected]
• About: https://jonas.ampferl.com/