pyEthTools: Python Ethereum Tools

• Supports python2 and python3 versions

1. Contains Ethereum JSON-RPC cover.
2. Hexnumber encode tools for encode additional parameters in transactions.
3. Hexnumber decode tools for decode data that contract returns.

Example of usage:

from pyethtools import PersonalRequest, Request
from pyethtools import hextools as ht

_ipcaddr = 'http://localhost', 8546
r = Request(*_ipcaddr)
pr = PersonalRequest(*_ipcaddr)

coinbase = r.eth_coinbase
account = pr.personal_newAccount("password") # returns accounts private address
contractAddress = "0x123" # as example

# To encode additional parameters:
method = "testCall(uint,uint32[],bytes10,string)"
# following two method calls are equal in 'web3.sha3(method)':
hexstr = ht.toHex(method)
print hexstr
# 0x7465737443616c6c2875696e742c75696e7433325b5d2c627974657331302c737472696e6729
signature = r.web3_sha3(hexstr)
print signature
# 0x96081302811f55aff14451d09c81b2a499b71fd6387d5480bb6b5afa56f0e663
txData = ht.getMethodID(signature) # 0x96081302 is methodID

unlocked = pr.personal_unlockAccount(account, "password") # returns True or False

# make transaction:
if unlocked:
    data = {
        "from" : account,
        "to"   : contractAddress,
        "gas"  : 10**6,

        # NB: On the giving list of parameters make sure that the additional
        # sequence of list is equals to a contract constructor, or function
        # call arguments for the required encoding, because 'getData' is not
        # a compiler.
        # Example of given function "testCall(uint,uint32[],bytes10,string)":
        "data" : ht.getData(
                [2**16, ['0x972', 123], "0123456789", "Hello, world!"],
                data=txData
                ),

        # getData returns single Hexnumber:
        # 0x96081302
        # 0000000000000000000000000000000000000000000000000000000000010000
        # 0000000000000000000000000000000000000000000000000000000000000080
        # 3031323334353637383900000000000000000000000000000000000000000000
        # 00000000000000000000000000000000000000000000000000000000000000e0
        # 0000000000000000000000000000000000000000000000000000000000000002
        # 0000000000000000000000000000000000000000000000000000000000000972
        # 000000000000000000000000000000000000000000000000000000000000007b
        # 000000000000000000000000000000000000000000000000000000000000000d
        # 48656c6c6f2c20776f726c642100000000000000000000000000000000000000
            }

    estimateGas = r.eth_estimateGas(data)
    txcost = estimateGas * r.eth_gasPrice
    if r.eth_getBalance(account) > txcost:
        tx = r.eth_sendTransaction(data)
        pr.personal_lockAccount(account)
        print tx # returns transaction hash
    else:
        print "balance is too low"

Example of decode:

Let's imagine that function returns single Hexnumber of (uint8, address, bytes10, string, uint[3], string):

0x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hx = ht.toHex("readData()")
methodID = ht.getMethodID(r.web3_sha3(hx))
data = {
    "from" : coinbase,
    "to"   : contractAddress,
    "data" : methodID,
}
methodData = r.eth_call(data)

# Now we will decode received methodData:
for l in ht.decodeData(methodData):
    print l

# So, the decodeData returns list of values:
# 255
# 0xca35b7d915458ef5401234568dfe2f44e8fa733c
# 123456789
# 340282366920938463463374607431768211456
# 545
# 0
# заза
# The Solidity optimizer operates on assembly, so it can be and also is
# used by other languages. It splits the sequence of instructions into
# basic blocks at JUMPs and JUMPDESTs. Inside these blocks, the instructions
# are analysed and every modification to the stack, to memory or storage is
# recorded as an expression which consists of an instruction and a list of
# arguments which are essentially pointers to other expressions. The main
# idea is now to find expressions that are always equal (on every input) and
# combine them into an expression class

# for more complex data we may use the 'decodeArgData':
for l in ht.decodeArgData(methodData, types=(int, hex, str, str, [int, int, int], str)):
    print l

# 255
# 0xca35b7d915458ef5401234568dfe2f44e8fa733c
# 123456789
# [340282366920938463463374607431768211456L, 545, 0]
# заза
# The Solidity optimizer operates on assembly, so it can be and also is
# used by other languages. It splits the sequence of instructions into
# basic blocks at JUMPs and JUMPDESTs. Inside these blocks, the instructions
# are analysed and every modification to the stack, to memory or storage is
# recorded as an expression which consists of an instruction and a list of
# arguments which are essentially pointers to other expressions. The main
# idea is now to find expressions that are always equal (on every input) and
# combine them into an expression class