Failed to establish a new connection: [WinError 10061] No connection could be made because the target machine actively refused it'))

[rishigarg256]

while using ganache cli and running the deploy simple storage program, i am getting this error
Traceback (most recent call last):
File "C:\anaconda\lib\site-packages\urllib3\connection.py", line 174, in _new_conn
conn = connection.create_connection(
File "C:\anaconda\lib\site-packages\urllib3\util\connection.py", line 96, in create_connection
raise err
File "C:\anaconda\lib\site-packages\urllib3\util\connection.py", line 86, in create_connection
sock.connect(sa)
ConnectionRefusedError: [WinError 10061] No connection could be made because the target machine actively refused it

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "C:\anaconda\lib\site-packages\urllib3\connectionpool.py", line 699, in urlopen
httplib_response = self._make_request(
File "C:\anaconda\lib\site-packages\urllib3\connectionpool.py", line 394, in _make_request
conn.request(method, url, **httplib_request_kw)
File "C:\anaconda\lib\site-packages\urllib3\connection.py", line 239, in request
super(HTTPConnection, self).request(method, url, body=body, headers=headers)
File "C:\anaconda\lib\http\client.py", line 1279, in request
self._send_request(method, url, body, headers, encode_chunked)
File "C:\anaconda\lib\http\client.py", line 1325, in _send_request
self.endheaders(body, encode_chunked=encode_chunked)
File "C:\anaconda\lib\http\client.py", line 1274, in endheaders
self._send_output(message_body, encode_chunked=encode_chunked)
File "C:\anaconda\lib\http\client.py", line 1034, in _send_output
self.send(msg)
File "C:\anaconda\lib\http\client.py", line 974, in send
self.connect()
File "C:\anaconda\lib\site-packages\urllib3\connection.py", line 205, in connect
conn = self._new_conn()
File "C:\anaconda\lib\site-packages\urllib3\connection.py", line 186, in _new_conn
raise NewConnectionError(
urllib3.exceptions.NewConnectionError: <urllib3.connection.HTTPConnection object at 0x000001523386F7F0>: Failed to establish a new connection: [WinError 10061] No connection could be made because the target machine actively refused it

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "C:\anaconda\lib\site-packages\requests\adapters.py", line 439, in send
resp = conn.urlopen(
File "C:\anaconda\lib\site-packages\urllib3\connectionpool.py", line 755, in urlopen
retries = retries.increment(
File "C:\anaconda\lib\site-packages\urllib3\util\retry.py", line 574, in increment
raise MaxRetryError(_pool, url, error or ResponseError(cause))
urllib3.exceptions.MaxRetryError: HTTPConnectionPool(host='127.0.0.1', port=7545): Max retries exceeded with url: / (Caused by NewConnectionError('<urllib3.connection.HTTPConnection object at 0x000001523386F7F0>: Failed to establish a new connection: [WinError 10061] No connection could be made
because the target machine actively refused it'))

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "C:\Users\Rishi Garg personal\demos\web3_py_simple_storage\deploy.py", line 100, in
nonce = w3.eth.getTransactionCount(my_address)
File "C:\anaconda\lib\site-packages\web3\module.py", line 57, in caller
result = w3.manager.request_blocking(method_str,
File "C:\anaconda\lib\site-packages\web3\manager.py", line 197, in request_blocking
response = self._make_request(method, params)
File "C:\anaconda\lib\site-packages\web3\manager.py", line 150, in _make_request
return request_func(method, params)
File "C:\anaconda\lib\site-packages\web3\middleware\formatting.py", line 94, in middleware
response = make_request(method, params)
File "C:\anaconda\lib\site-packages\web3\middleware\gas_price_strategy.py", line 90, in middleware
return make_request(method, params)
File "C:\anaconda\lib\site-packages\web3\middleware\formatting.py", line 94, in middleware
response = make_request(method, params)
File "C:\anaconda\lib\site-packages\web3\middleware\attrdict.py", line 33, in middleware
response = make_request(method, params)
File "C:\anaconda\lib\site-packages\web3\middleware\formatting.py", line 94, in middleware
response = make_request(method, params)
File "C:\anaconda\lib\site-packages\web3\middleware\formatting.py", line 94, in middleware
response = make_request(method, params)
File "C:\anaconda\lib\site-packages\web3\middleware\formatting.py", line 94, in middleware
response = make_request(method, params)
File "C:\anaconda\lib\site-packages\web3\middleware\buffered_gas_estimate.py", line 40, in middleware
return make_request(method, params)
File "C:\anaconda\lib\site-packages\web3\middleware\exception_retry_request.py", line 105, in middleware
return make_request(method, params)
File "C:\anaconda\lib\site-packages\web3\providers\rpc.py", line 88, in make_request
raw_response = make_post_request(
File "C:\anaconda\lib\site-packages\web3_utils\request.py", line 48, in make_post_request
response = session.post(endpoint_uri, data=data, *args, **kwargs) # type: ignore
File "C:\anaconda\lib\site-packages\requests\sessions.py", line 590, in post
return self.request('POST', url, data=data, json=json, **kwargs)
File "C:\anaconda\lib\site-packages\requests\sessions.py", line 542, in request
resp = self.send(prep, **send_kwargs)
File "C:\anaconda\lib\site-packages\requests\sessions.py", line 655, in send
r = adapter.send(request, **kwargs)
File "C:\anaconda\lib\site-packages\requests\adapters.py", line 516, in send
raise ConnectionError(e, request=request)
requests.exceptions.ConnectionError: HTTPConnectionPool(host='127.0.0.1', port=7545): Max retries exceeded with url: / (Caused by NewConnectionError('<urllib3.connection.HTTPConnection object at 0x000001523386F7F0>: Failed to establish a new connection: [WinError 10061] No connection could be made because the target machine actively refused it'))

below is the code

`# this file has been created to work with ganache cli
# this file is to figure out how we deploy the simple storage solidity code in python
#'first we read the solidity file'
# we use py-solc-x as our compiler
# always use formatter to be blsck (python formatting provider for better code writing)

from itertools import chain
from numpy import signedinteger
from solcx import compile_standard, install_solc
import json
from web3 import Web3, HTTPProvider

import os  # for getting private key
from dotenv import load_dotenv


load_dotenv()  # this load_dotenv() looks for this .env file and automatically imports it into our script


with open("./SimpleStorage.sol", "r") as file:
    simple_storage_file = file.read()
    # print(simple_storage_file)

    # compile our solidity
install_solc("0.6.0")

compiled_sol = compile_standard(  # this is equal to us calling this compile standard function where we are using the compiler
    {
        "language": "Solidity",
        "sources": {"SimpleStorage.sol": {"content": simple_storage_file}},
        "settings": {
            "outputSelection": {
                "*": {"*": ["abi", "metadata", "evm.bytecode", "evm.sourceMap"]}
            }
        },
    },
    solc_version="0.6.0",
)


# print(compiled_sol)  # gives the low level code

with open("compiled_code.json", "w") as file:
    json.dump(
        compiled_sol, file
    )  # this line will take our compiled_sol json variable and just dump it into this file but it will keep it in the json syntax

# to deploy, we first need the bytecode of the file so that we can actually deploy it

bytecode = compiled_sol["contracts"]["SimpleStorage.sol"]["SimpleStorage"]["evm"][
    "bytecode"
]["object"]
# what we are doing above is when we're typing in all these words like contract, simplestorage, simple storage, is we're walking down the json file here
# its really low level stuff

# getting abi

abi = compiled_sol["contracts"]["SimpleStorage.sol"]["SimpleStorage"]["abi"]
# print(abi)

# to test this, we use ganache, which is a simulated or a fake blockchain that we can use to deploy our smart contracts to, interact like its a real blockchain
# ganache is going to allow us to spin up our own blockchain. Ganache is our javascript Vm
# in remix, metamask is our http provider
# we will use the rpc server url in ganache(top middle situated) to connect to this blockchain


# for connecting to ganache
w3 = Web3(
    Web3.HTTPProvider("http://127.0.0.1:8545") #changed to loopback address
)  # remember to use the documentation for web3 web3py.readthedocs.io
# next we are gonna need is the chain id or the network id
chain_id = 1337
my_address = "0x90F8bf6A479f320ead074411a4B0e7944Ea8c9C1"
# private_key = "0x112690d5ad13f5c21795a3fa1056a3193061556e42ddad0aa78f141462cbf941"  # private Keys must start with 0x (just add it at the front). python is always gonna look for the hexadecimal version of the private key
# never hardcode your private keys, as if we push to github, they can see our private keys.
# environment variables: they are variables that we can set in our terminal and our command lines
# exported environment variables only last the duration of the shell/terminal
private_key = os.getenv(
    "PRIVATE_KEY"
)  # using this command, our python script can pull our private key from our environment variable
# .env file is where people store envioronment variables. if we do the .env file way, create another file called .gitignore which will make it harder for us to accidently push my .envfolder or .envfile to github
# loading .env in python, gotta install pip install python-dotenv and then go at the top where we write the import statement

print(
    os.getenv("PRIVATE_KEY")
)  # look at the .env file for the PRIVATE_KEY variable. we can also print private_key


# deploying

SimpleStorage = w3.eth.contract(
    abi=abi, bytecode=bytecode
)  # this doesnt mean we have deployed, it just means we have a contract down
# print(SimpleStorage)

# definition for nonce(in cryptography): an arbitrary number that can be used just once in a cryptographic communication, this is when we studied about nonce initially

# over here the account nonces just rack the number of transactions made by our account

# we can actually get our nonce by just grabbing our latest transaction count. getting latest transaction
nonce = w3.eth.getTransactionCount(my_address)
# print(nonce)
# to deploy this contract, we need to make a transaction
# we need to build our transactions. 1. Build the contract deploy transaction
# 2. Sign the transaction
# 3. Send the transaction
transaction = SimpleStorage.constructor().buildTransaction(
    {
        "gasPrice": w3.eth.gas_price,  # Otherwise you get a value error if you don't set the gasPrice
        "chainId": chain_id,
        "from": my_address,
        "nonce": nonce,
    }
)  # every contract has atleast an implied constructor
# we need to have transaction parameters (atleast a couple of parameters we always have to give)
# so we have this transaction buut we need to sign it from somebody. Since we are sending it from our address, our private key is gonna be the only key thats going to work to sign this

# print(transaction)
signed_txn = w3.eth.account.sign_transaction(transaction, private_key=private_key)

# print(signed_txn)  # this is a signed transaction

# now we want to send this signed transaction to the blockhain

# send this signed transaction
print("Deploying contract...")
tx_hash = w3.eth.send_raw_transaction(
    signed_txn.rawTransaction
)  # we dont print anything but the transaction did go through, if we look at ganache

# one other thing thats really good practice whenever sending a transaction is we wait for some block transactions to happen

tx_receipt = w3.eth.wait_for_transaction_receipt(
    tx_hash
)  # this will have our code stop and wait for this transaction hash to go through

print("Deployed")
# now we have deployed the contract, but how do we actually interact and work with the contract

# working with a contract
# we need contract address and the contract abi

# Working with deployed contracts
simple_storage = w3.eth.contract(
    address=tx_receipt.contractAddress, abi=abi
)  # creating this simple storage contract so we can interact with it

# when making transactions in the blockchain, there are actually 2 ways that we can interaact with them
# call -> Simulate making the call and getting a return value; calls dont make a state change; likein remix, the blue buttons were the calls, orange ones were the transacts

# transact -> actually make a state change
print(
    simple_storage.functions.retrieve().call()
    # initial value for our retireve function (favourite number)
)
print("Updating contract...")
# print(simple_storage.functions.store(15).call())  # in simplestorage, the store function returns a value(over here 15)

# now since we want to make a transaction to actually store some value into this contract. since we want to make a transaction,
# we got to go through the same process as when we deployed this contract
# remember nonce can only be used once for each transaction, thats why this nonce is different from the previous one we used earlier at the top

store_transaction = simple_storage.functions.store(13).buildTransaction(
    {
        "chainId": chain_id,
        "gasPrice": w3.eth.gas_price,
        "from": my_address,
        "nonce": nonce + 1,
    }
)  # this is creating a transaction

# then we will sign the transaction
signed_store_txn = w3.eth.account.sign_transaction(
    store_transaction, private_key=private_key
)
# we send the transaction (transaction hash)
send_store_tx = w3.eth.send_raw_transaction(signed_store_txn.rawTransaction)
# we wait for the transaction to finish
tx_receipt = w3.eth.wait_for_transaction_receipt(send_store_tx)
print("Updated")

# now printing it would show 13. started at 0, now its 13
print(simple_storage.functions.retrieve().call())
# we have made our first state change to a contract that we have deployed on our local blockchain


# we are installing node.js and yarn (yarn is a package manager similar to pip and will allow us to actually download pieces and packages like the ganache cli from package repository)
# we install using npm install --global yarn
# then installing actual ganache cli using yarn global add ganache cli (npnjs.com/package/ganache-cli)
# if we want the same private keys everytime, we use ganache-cli --deterministic (see the documentation)
# 127.0.0.1:7545 is also known as the loopback address or the localhost
# to work with ganache cli
#1. Update Private Keys
#2. Update Addresses
#3. Update HTTPProvider/ RPC URL
#now we open a new terminal in the same window (do make sure to close the ganache gui application otherwise there will be conflict)
`

[cromewar]

Hello @rishigarg256

1. Please do not use anaconda/conda environments for web3 development, there are some incompatible libraries, use regular pip on a virtual env instead (in preference v3.8 o 3.9).
2. Be sure your firewall is not blocking your ganache instance, seems is unable to connect correctly to it.
3. Be sure the port you are using in ganache are the same as you are using on your code (7545).