extract.py

import json
import glob
from sha3 import keccak_256

functionHashes = open("extract/functionHashes.txt","w+")
for file in list(glob.glob('build/contracts/*.json')):   
    reader = open(file)
    j = json.load(reader)

    index_of_dot = reader.name.index('.')
    file_name_without_extension1 = reader.name[:index_of_dot]
    file_name_without_extension = file_name_without_extension1.split('/')[-1]

    f = open("extract/"+file_name_without_extension+".abi.txt","w+")
    f.write(json.dumps(j['abi']))      
    f.close

    f = open("extract/"+file_name_without_extension+".bytecode.txt","w+")
    f.write(j['bytecode'])   
    f.close
    

    abi = j['abi']
    
    functionSelector = []
    for fields in abi:
        if(fields['type'] == 'function'):
            functionName = fields['name']
            functionInputs = []
            for inputs in fields['inputs']:
                functionInputs.append(inputs['type'])
            functionSelector.append([functionName, functionInputs])
    for functions in functionSelector:
        functionName = functions[0]
        functionType = functions[1]
        s = functionName + '('
        for i in range(len(functionType)):
            s += functionType[i]
            if(i+1 < len(functionType)):
                s += ','
        s += ')'
        sha3_hash = keccak_256(s.encode('utf-8')).hexdigest()
        ss = "functionHashes.set('" + sha3_hash[:8] + "', '" + s + "');"
        print >> functionHashes, ss

functionHashes.close