My-own-blockchain

If you want to read only purpose of functions, pls skip this boring introduction

In brief. My idea was to finally answer "What the hell is even this blockchain is?".

Don't understand something. Build it.

So, my goofy plan was:

1. Read A LOT OF DOCS 
2. Write simple, but functionally complete blockchain in golang 
3. Look for exaplme in Geth(go etherium); ask a team-lead; read repo again 
4. Re-write it all with patterns
5. Write tests
6. Write fixes after tests
7. Be happy with my work (never happen)

My next step is to make a blog page with Next.Js with complete overview for the entire project, but for now let it stay in the way it is

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blockchain.go

• InitBlockchain(address, nodeId): Create initial blockchain with genesis block
• ContinueBlockchain(nodeId): Restore existing blockchain
• MineBlock(transaction): Create and add new block with transactions
• VerifyTransaction(t *Transaction): Validate transaction integrity
• FindUniqueTransaction(address): Retrieve transactions for specific address
• GetBestHeightAndLastHash(): Get current blockchain height and last block hash

block.go

• CreateBlock(txs, prevHash, height): Generate new block with transactions
• CreateGenesis(coinbase): Create initial genesis block
• HashTransactions(): Generate Merkle root for block's transactions
• Serialize(): Convert block to byte array
• DeserializeBlock(data): Reconstruct block from byte array

transaction.go

• NewTransaction(wallet, to, amount, UTXO): Create new transaction
• Sign(privateKey, prevTransactions): Sign transaction with private key
• Verify(prevTransactions): Validate transaction signatures
• IsCoinbase(): Check if transaction is a coinbase (mining reward)
• CoinbaseTx(to, data): Create coinbase transaction for mining rewards

unspent.go

• Reindex(): Rebuild UTXO set
• Update(block): Update UTXO set after new block
• FindSpendableOutputs(pubKeyHash, amount): Find unspent outputs for transaction
• CountUnspentOuts(): Count total unspent transaction outputs

proof.go

• NewProof(block): Create proof of work for block
• Run(): Mine block by finding valid nonce
• Validate(): Check if block's proof of work is valid

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wallet.go

CreateWallets(nodeId string) (*Wallets, error)

Initializes a `Wallets` instance, loads wallet data from a file associated with the given `nodeId`, and returns the instance.

AddWallet() string

Creates a new wallet with a unique private/public key pair, generates an address, and adds the wallet to the `Wallets` collection. Returns the generated address.

GetWallet(address string) *Wallet

Retrieves a wallet from the `Wallets` collection using its address as the key.

GetAllAddresses() []string

Returns a list of all wallet addresses stored in the `Wallets` collection.

loadFile(nodeId string) error

Loads wallet data from a file associated with the given `nodeId`. If the file doesn't exist, it returns an error.

SaveFile(nodeId string)

Saves the current `Wallets` collection to a file associated with the given `nodeId`.

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wallets.go

Address() []byte

Generates a wallet address by applying a series of hashing algorithms (SHA-256 and RIPEMD-160) and encoding the result with Base58. Includes a version byte and a checksum.

newKeyPair() (ecdsa.PrivateKey, []byte)

Generates a new key pair for a wallet. Uses the P256 elliptic curve to create a private key and derives the public key from it.

PublicKey(pubkey []byte) []byte

Generates a public key hash by applying SHA-256 and RIPEMD-160 hashing algorithms to the provided public key.

checkSum(payload []byte) []byte

Computes a checksum for a given payload by applying SHA-256 twice and returning the first 4 bytes of the result.

ValidateAddress(address string) bool

Validates a wallet address by verifying its checksum and ensuring it matches the hash of the public key.

makeWallet() *Wallet

Creates a new `Wallet` by generating a private/public key pair and initializing a `Wallet` instance with these keys.

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Resources used in development

Beyond good website that i wish i found earlier:

https://learnmeabitcoin.com/

https://github.com/ethereum/go-ethereum