I posted a question yesterday but deleted it, since I did things differently. However, the problem remains the same and I really need to get through this:
GOAL
Automatically connect to Parity account, automatize the use of a smart contract with web3
smart contract
That contract simply notarizes (put into the bockchain) a string. The function to call is Notarize("whatever you want")
my code
# -*- coding: utf-8 -*-
# -*- coding: utf-8 -*-
from web3 import Web3, HTTPProvider
import subprocess
import json
import time
#launching parity, chain: kovan testnet, using TOML file (must be correctly configured!)
#subprocess.run() or call() won't work as it doesn't return until it is finished. Popen() does the trick
#finally, runing only "parity.exe" will run the FUNDATION chain without the CLI taken into account. So, CLI must be added as well
subprocess.Popen('C:\Program Files\Parity Technologies\Parity\parity.exe --chain "kovan" --jsonrpc-apis "eth,net,web3,personal,parity" --pruning "fast" --tracing "off" --fat-db "off"')
#let some time before the next command
time.sleep(5)
#interacting with blockchain client as a HTTP object
w3= Web3(HTTPProvider("http://127.0.0.1:8180"))
#unlocking account
w3.personal.unlockAccount("0x00.....", "password")
test=w3.eth.blockNumber
print(test)
#define contract adress and contract instance
contractAddress="0xdE..."
#define abi JSON of smartcontract, parsing it and using it further as contract instance
with open("C:/Users/jaekl/Documents/scripts/python/ethereum_blockchain.json", "r") as f:
abi=json.load(f)
#contract instance:
contract_instance=w3.eth.contract(abi, contractAddress)
#using the function "notarize" of the smart contract to send a string on the blockchain kovan
to_send=contract_instance.transact({"from":"0x00..."}) .notarize("a string")
ERROR/problem
I can connect to Parity with the subprocess. I manage to see the last block for exemple (see code). But I need to unlock my account in order to interact with my contract. However, an error keeps poping up:
runfile('C:/Users/jaekl/Documents/scripts/python/ethereum_blockchain/parity_automatization.py', wdir='C:/Users/jaekl/Documents/scripts/python/ethereum_blockchain')
Traceback (most recent call last):
File "<ipython-input-1-92ff1f4de1cb>", line 1, in <module>
runfile('C:/Users/jaekl/Documents/scripts/python/ethereum_blockchain/parity_automatization.py', wdir='C:/Users/jaekl/Documents/scripts/python/ethereum_blockchain')
File "C:\Users\jaekl\Anaconda3\lib\site-packages\spyder\utils\site\sitecustomize.py", line 880, in runfile
execfile(filename, namespace)
File "C:\Users\jaekl\Anaconda3\lib\site-packages\spyder\utils\site\sitecustomize.py", line 102, in execfile
exec(compile(f.read(), filename, 'exec'), namespace)
File "C:/Users/jaekl/Documents/scripts/python/ethereum_blockchain/parity_automatization.py", line 22, in <module>
w3.personal.unlockAccount("0x00...", "password")
File "C:\Users\jaekl\Anaconda3\lib\site-packages\web3\personal.py", line 93, in unlockAccount
[account, passphrase, duration],
File "C:\Users\jaekl\Anaconda3\lib\site-packages\web3\manager.py", line 96, in request_blocking
raise ValueError(response["error"])
ValueError: {'code': -32601, 'message': 'Method not found'}
I tried everything possible. Read a lot of posts/issues about the CLI or TOML configuration. I run parity as follow:
"C:\Program Files\Parity Technologies\Parity\parity.exe" --chain "kovan" --jsonrpc-apis "eth,net,web3,personal,parity" --pruning "fast" --tracing "off" --fat-db "off"
But it doesn't work ! I am becoming crazy about that.
What am I doing wrong? Is the way I configure parity CLI options not correct ? Do I really need to unlock my account to interact with my contract?
Thank you very much !
Loïc
