/ 
Web3-Tiny-0.01
/ README.md

Web3::Tiny

A small, dependency-light way to talk to Ethereum (and other EVM chains) from Perl.

use Web3::Tiny;
use Web3::Tiny::Util qw(to_wei from_wei);

my $web3 = Web3::Tiny->new(rpc_url => 'https://ethereum-rpc.publicnode.com');

print $web3->block_number, "\n";
print from_wei($web3->get_balance('0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045')), " ETH\n";

my $weth = $web3->contract(
    address => '0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2',
    abi     => {
        symbol    => { sig => 'symbol()',           returns => ['string']  },
        balanceOf => { sig => 'balanceOf(address)', returns => ['uint256'] },
    },
);
print $weth->call('symbol'), "\n";                       # WETH
print $weth->call('balanceOf', $web3_address), "\n";     # raw wei, as a Math::BigInt

# sign and send a transaction
my $wallet = $web3->wallet(private_key => '0x...');
my $erc20  = $web3->contract(
    address => '0x...',
    abi     => { transfer => { sig => 'transfer(address,uint256)', returns => ['bool'] } },
);
my $tx_hash = $erc20->send($wallet, 'transfer', $to_address, to_wei('1.5'));

Why

A handful of CPAN modules already talk to Ethereum's JSON-RPC API -- Net::Ethereum, Ethereum::RPC::Client, and Blockchain::Ethereum among them -- but each either predates modern Solidity ABI features (arrays, full scalar-type coverage) or reinvents the crypto primitives by hand in pure Perl. Web3::Tiny's crypto (Web3::Tiny::Secp256k1, Web3::Tiny::Keccak256) is a thin wrapper around CryptX, an XS module wrapping the well-audited libtomcrypt C library, instead of a pure-Perl reimplementation -- everything else (Math::BigInt, HTTP::Tiny, JSON::PP) is Perl core.

cpanm CryptX

What's in here

| Module | Purpose | |----------------------------|-----------------------------------------------------| | Web3::Tiny | Facade: connect, read balances/nonces, mint wallets/contracts | | Web3::Tiny::RPC | JSON-RPC 2.0 transport | | Web3::Tiny::ABI | Solidity ABI encode/decode + function selectors | | Web3::Tiny::Wallet | Private key -> address, EIP-155 transaction signing | | Web3::Tiny::Contract | Bind an address + method list, call/send | | Web3::Tiny::Secp256k1 | secp256k1 ECDSA (sign/verify/recover), via CryptX | | Web3::Tiny::Keccak256 | Keccak-256 (Ethereum's flavor, not NIST SHA3), via CryptX | | Web3::Tiny::RLP | Recursive Length Prefix encoding | | Web3::Tiny::Util | to_wei/from_wei and hex/bigint helpers |

Scope

Supports the common Solidity ABI scalar types plus T[]/T[k] arrays of them (no tuples/structs, no arrays-of-arrays), and legacy (pre-EIP-1559) transactions with EIP-155 replay protection. Every primitive here has been checked against known-good vectors (Ethereum wiki RLP examples, the Solidity ABI spec's own worked example, EIP-55's checksum test vectors, well-known ERC20 selectors, and live eth_calls against WETH on mainnet).

Not in scope for v0.01: EIP-1559 transactions, event log decoding, ENS.

Installing

perl Makefile.PL
make
make test
make install

Testing

prove -lv t/

Every module has its own test file (t/NN-name.t) checked against known-good vectors rather than just round-tripping its own output:

| File | Covers | |--------------------------------|----------------------------------------------------------------| | t/00-load.t | Every module compiles and loads | | t/10-keccak256.t | keccak256("")/"abc" KATs, ERC20 selectors, event topic0 | | t/11-keccak256-vectors.t | Longer Keccak-256 vectors, incl. padding at/around the 136-byte block boundary | | t/20-secp256k1.t | ECDSA sign/verify/recover round-trips | | t/30-rlp.t | Ethereum wiki RLP encoding examples | | t/40-abi.t | Solidity ABI spec's own worked encode/decode example | | t/50-wallet.t | EIP-55 checksum vectors, EIP-155 signed-tx recovery | | t/60-util.t | to_wei/from_wei and hex/bigint helpers |

Before uploading to CPAN

This is a fresh distribution that has not been published yet. Before cpan-upload:

License

Same terms as Perl itself.