brownie.exceptions.RPCRequestError: Web3 is not connected - brownie

Question

I am trying to deploy a helloWorld.sol using brownie. I am getting below error when I tried to run brownie run scripts/deploy.py.
Terminating local RPC client... Exception in thread Thread-5:
Traceback (most recent call last): File
"C:\Users\mmasn.local\pipx\venvs\eth-brownie\lib\site-packages\urllib3\connection.py",
line 175, in _new_conn
(self._dns_host, self.port), self.timeout, **extra_kw File "C:\Users\mmasn.local\pipx\venvs\eth-brownie\lib\site-packages\urllib3\util\connection.py",
line 96, in create_connection
raise err File "C:\Users\mmasn.local\pipx\venvs\eth-brownie\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:\Users\mmasn.local\pipx\venvs\eth-brownie\lib\site-packages\urllib3\connectionpool.py",
line 706, in urlopen
chunked=chunked, File "C:\Users\mmasn.local\pipx\venvs\eth-brownie\lib\site-packages\urllib3\connectionpool.py",
line 394, in _make_request
conn.request(method, url, **httplib_request_kw) File "C:\Users\mmasn.local\pipx\venvs\eth-brownie\lib\site-packages\urllib3\connection.py",
line 239, in request
super(HTTPConnection, self).request(method, url, body=body, headers=headers) File "C:\Program
Files\Python37\lib\http\client.py", line 1229, in request
self._send_request(method, url, body, headers, encode_chunked) File "C:\Program Files\Python37\lib\http\client.py", line 1275, in
_send_request
self.endheaders(body, encode_chunked=encode_chunked) File "C:\Program Files\Python37\lib\http\client.py", line 1224, in
endheaders
self._send_output(message_body, encode_chunked=encode_chunked) File "C:\Program Files\Python37\lib\http\client.py", line 1016, in
_send_output
self.send(msg) File "C:\Program Files\Python37\lib\http\client.py", line 956, in send
self.connect() File "C:\Users\mmasn.local\pipx\venvs\eth-brownie\lib\site-packages\urllib3\connection.py",
line 205, in connect
conn = self._new_conn() File "C:\Users\mmasn.local\pipx\venvs\eth-brownie\lib\site-packages\urllib3\connection.py",
line 187, in _new_conn
self, "Failed to establish a new connection: %s" % e urllib3.exceptions.NewConnectionError:
<urllib3.connection.HTTPConnection object at 0x0000021DAA2A0F28>:
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\mmasn.local\pipx\venvs\eth-brownie\lib\site-packages\requests\adapters.py",
line 449, in send
timeout=timeout File "C:\Users\mmasn.local\pipx\venvs\eth-brownie\lib\site-packages\urllib3\connectionpool.py",
line 756, in urlopen
method, url, error=e, _pool=self, _stacktrace=sys.exc_info()[2] File
"C:\Users\mmasn.local\pipx\venvs\eth-brownie\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=8545): Max retries exceeded with url: / (Caused by
NewConnectionError('<urllib3.connection.HTTPConnection object at
0x0000021DAA2A0F28>: 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\mmasn.local\pipx\venvs\eth-brownie\lib\site-packages\brownie\network\rpc\ganache.py",
line 82, in _request
response = web3.provider.make_request(method, args) # type: ignore File
"C:\Users\mmasn.local\pipx\venvs\eth-brownie\lib\site-packages\web3\providers\rpc.py",
line 91, in make_request
**self.get_request_kwargs() File "C:\Users\mmasn.local\pipx\venvs\eth-brownie\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:\Users\mmasn.local\pipx\venvs\eth-brownie\lib\site-packages\requests\sessions.py",
line 590, in post
return self.request('POST', url, data=data, json=json, **kwargs) File
"C:\Users\mmasn.local\pipx\venvs\eth-brownie\lib\site-packages\requests\sessions.py",
line 542, in request
resp = self.send(prep, **send_kwargs) File "C:\Users\mmasn.local\pipx\venvs\eth-brownie\lib\site-packages\requests\sessions.py",
line 655, in send
r = adapter.send(request, **kwargs) File "C:\Users\mmasn.local\pipx\venvs\eth-brownie\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=8545): Max retries exceeded
with url: / (Caused by
NewConnectionError('<urllib3.connection.HTTPConnection object at
0x0000021DAA2A0F28>: 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:\Program
Files\Python37\lib\threading.py", line 917, in _bootstrap_inner
self.run() File "C:\Program Files\Python37\lib\threading.py", line 865, in run
self._target(*self._args, **self._kwargs) File "C:\Users\mmasn.local\pipx\venvs\eth-brownie\lib\site-packages\brownie\network\state.py",
line 332, in add_to_undo_buffer
self.sleep(0) File "C:\Users\mmasn.local\pipx\venvs\eth-brownie\lib\site-packages\brownie\network\state.py",
line 375, in sleep
self.time_offset = int(rpc.Rpc().sleep(seconds)) File "C:\Users\mmasn.local\pipx\venvs\eth-brownie\lib\site-packages\brownie\network\rpc_init.py",
line 45, in wrapped
return fn(*args, **kwargs) File "C:\Users\mmasn.local\pipx\venvs\eth-brownie\lib\site-packages\brownie\network\rpc_init.py",
line 166, in sleep
return self.backend.sleep(seconds) File "C:\Users\mmasn.local\pipx\venvs\eth-brownie\lib\site-packages\brownie\network\rpc\ganache.py",
line 91, in sleep
return _request("evm_increaseTime", [seconds]) File "C:\Users\mmasn.local\pipx\venvs\eth-brownie\lib\site-packages\brownie\network\rpc\ganache.py",
line 86, in _request
raise RPCRequestError("Web3 is not connected.") brownie.exceptions.RPCRequestError: Web3 is not connected.
My deploy.py code is below.
from brownie import accounts, HelloWorld
def deployHelloWorld():
account = accounts[0]
helloWorldObject = HelloWorld.deploy({"from": account})
helloWorldObject.setName("Michael", {"from": account})
greeting = helloWorldObject.sayHello()
print(greeting)
def main():
deployHelloWorld()
could you please help?

Answer 1

This error is caused because there is no waiting after transaction. By using transaction.wait(1), as below, the problem is fixed.
transaction = helloWorldObject.setName("Michael", {"from": account})
transaction.wait(1)
greeting = helloWorldObject.sayHello()
print(greeting)

Answer 2

RPC is sometimes killed too quick, resulting in brownie.exceptions.RPCRequestError: Web3 is not connected.
Therefore you have to add the time.sleep(1) after every transaction to ensure your code runs smoothly.

Answer 3

You need to put after transactions
transactionVariable.wait(1)
time.sleep(1)