Brownie / Rinkeby ValueError: Gas estimation failed: "you must set the gas limit manually"

Question

from brownie import AdvancedCollectible, accounts, config, network
from scripts.helpful_scripts import get_breed
import time

static_seed = 123

def main():
    dev = accounts.add(config["wallets"]["from_key"])
    advanced_collectible = AdvancedCollectible[len(AdvancedCollectible) - 1]
    transaction = advanced_collectible.createCollectible(static_seed, "None", {"from": dev})
    print("Waiting on second transaction...")
    # wait for the 2nd transaction
    transaction.wait(1)
    requestId = transaction.events["requestedCollectible"]["requestId"]
    token_id = advanced_collectible.requestIdToTokenId(requestId)
    time.sleep(35)
    breed = get_breed(advanced_collectible.tokenIdToBreed(token_id))
    print("Dragotherium breed of tokenId {} is {}".format(token_id, breed))

Error:

Error : Running 'scripts\advanced_collectible\create_collectible.py::main'...
  File "C:\Users\SM\AppData\Local\Programs\Python\Python310\lib\site-packages\brownie\_cli\run.py", line 49, in main
    return_value, frame = run(
  File "C:\Users\SM\AppData\Local\Programs\Python\Python310\lib\site-packages\brownie\project\scripts.py", line 103, in run
    return_value = f_locals[method_name](*args, **kwargs)
  File ".\scripts\advanced_collectible\create_collectible.py", line 10, in main
    transaction = advanced_collectible.createCollectible(static_seed, "None", {"from": dev})
  File "C:\Users\SM\AppData\Local\Programs\Python\Python310\lib\site-packages\brownie\network\contract.py", line 1693, in __call__
    return self.transact(*args)
  File "C:\Users\SM\AppData\Local\Programs\Python\Python310\lib\site-packages\brownie\network\contract.py", line 1566, in transact
    return tx["from"].transfer(
  File "C:\Users\SM\AppData\Local\Programs\Python\Python310\lib\site-packages\brownie\network\account.py", line 642, in transfer
    receipt, exc = self._make_transaction(
  File "C:\Users\SM\AppData\Local\Programs\Python\Python310\lib\site-packages\brownie\network\account.py", line 725, in _make_transaction
    raise VirtualMachineError(e) from None
  File "C:\Users\SM\AppData\Local\Programs\Python\Python310\lib\site-packages\brownie\exceptions.py", line 121, in __init__
    raise ValueError(str(exc)) from None
ValueError: Gas estimation failed: 'execution reverted'. This transaction will likely revert. If you wish to broadcast, you must set the gas limit manually.  

Answer 1

I think this has already been answered here. To summarize it, you probably have vrf_coordinator version error. Try the rinkeby's values from the official docs. Try changing values in the config.yaml.

vrf_coordinator:'0xb3dCcb4Cf7a26f6cf6B120Cf5A73875B7BBc655B'
link_token: '0x01BE23585060835E02B77ef475b0Cc51aA1e0709' keyhash:'0x2ed0feb3e7fd2022120aa84fab1945545a9f2ffc9076fd6156fa96eaff4c1311'

Answer 2

Try this on a dev net (do not do this on main-net):

....
# arbitrary gasLimit amount...
myAwesomeGasLimit = 50000 

transaction = advanced_collectible.createCollectible(
                    static_seed, 
                    "None", 
                    {"from": dev, "gasLimit": myAwesomeGasLimit}
               )
....
 

If it works then it's an issue w/ your gasLimit. To narrow it down, try also playing with the other "parameters of a typical Eth transaction" :

reference doc'n:

Parameters of a typical Ethereum transaction

from: The sender address, a 20-byte address representing the account initiating the transaction. ...... ......

gasLimit: This is the maximum amount in wei that a transaction can use as gas.