Web3.jl

A module for Ethereum connectivity.

Parse ABI files, encode/decode ABI data, and make Ethereum JSON-RPC calls: low-level calls, smart contract function calls and transactions.

This is a work in progress but work seems to be progressing...

Here are some examples

Simple use

Access a contract

• ctr = ContractContext("http://localhost:8545", "0x4ED124fcf412C28E4f36790a3A88056a5c44ade2", "abi.json") -- create a contract context (a contract associated with a connection)
• ctr.myFunc.call(arg) -- call a function, returns the result as a Julia value(s)
• ctr.myFunc.send(arg, arg) -- send a transaction, returns the result as a Julia value(s)

Structure

Structs

• Web3Connection(url): a JSON-RPC connection to an Ethereum node
• Contract(functions, events): A contract's function and event declarations
• ABIFunction(constant, hash, inputs, name, outputs, payable, signature, statemutability, argtypes)
• ContractContext(connection, contract)

Variables

• contracts: a dictionary of contract-address => Contract structures

Functions

• readABI(con::Web3Connection, contractname::String, stream::IO): Read an ABI file for a contract
• encodefunctioncall(io::IO, f::ABIFunction, inputs::Array): Encode a call to a function
• encodefunctioncall(io::IOBuffer, f::ABIFunction, inputs::Array): Encode a call to a function, returns buffer data
• encodefunctionresult(io::IO, f::ABIFunction, outputs::Array): Encode the results of a function
• encodefunctionresult(io::IOBuffer, f::ABIFunction, outputs::Array): Encode the results of a function, returns buffer data
• encodeevent(io::IO, e::ABIEvent, inputs::Array): Encode an event
• encodeevent(io::IOBuffer, e::ABIEvent, inputs::Array): Encode an event, returns buffer data
• decodefunctioncall(io::IO, con::Contract): Decode a function call
• decodefunctionresult(io::IO, con::Contract): Decode a function call result
• decodeevent(io::IO, con::Contract): Decode an event in a transaction log

API Calls

These aren't all filled in yet but see the package source for a simple way to add more...

• clientversion(con::Web3Connection): returns the client version
• eth: eth API
  • eth.gettransactioncount(con::Web3Connection, addr, context): Get transaction count for a given address and context ("latest", "earliest", "pending", or a block number)
  • eth.gettransactionbyhash(con::Web3connection, hash): Get a transaction
• util: util API
  • util.sha3(con::Web3Connection, str::String): get the keccak hash of a string
  • util.keccak(con::Web3Connection, str::String): get the keccak hash of a string