Lesson 11: Verifying AdvancedCollectible Contract On Etherscan

[Nlferu]

Hello,

At around 10:50:00 and later on in course Patrick is showing verified contract details (his contract has been verified automatically somehow). In my case none of my contracts has been verified (I have already tried tons of times). I have also tried to manually publish and verify deployed contract but I keep getting error that it does not recognize my 2 imports of ERC721 and VRFConsumerBase. I have also tried to use following line of code in my deploy script: publish_source = config["networks"][network.show_active()].get("verify", False), but it throws below error:

Error from etherscan manual verification:

Anyone can help me to solve this issue? I'm unable to see if my tokenCounter works properly.

[cromewar]

Hello @Neftyr
The reason Patrick contracts get verified automatically is because the code is exactly the same as a previous contract. The reasons is because when a contract have the same code the bytecode will be also the same, so if a contract with the same bytecode was already verified the verification will pass automatically.

Regarding to your issue, please share the following:
Your brownie-config.yaml.

And remember to have setup the etherscan key on .env

[Nlferu]

I have also tried to returning tokenCounter value and printing it to avoid verifying but it always shows 0.

Ok at least i figured out why it shows 0:

We would use below right away but it would return us primal version of "tokenCounter", which equals to "0", so we have to call version updated by "fulfillRandomness" function

assert advanced_collectible.tokenCounter() > 0

We have to:
1. Call "requestId" from "emit" function from "AdvancedCollectible" contract.
2. Call "callBackWithRandomness" function from VRFCoordinatorMock contract and fill it with above.
3. It can now callBack our "advanced_collectible.address" and update it with requestId and random_number, so our "advanced_collectible.tokenCounter()" will now return 1.

Of course correct me if I'm wrong, but if above understanding is correct i hope this can help someone understand it better.

I was also trying to solve below error, but unfortunately nothing is working and I'm keep getting it and i cannot verify my contract...

[cromewar]

You are right that's exactly how it works, the 3 steps you explained are just fine..
Regarding to your problem I'm going to need a little bit more info on this:

1. Share the command you are using to run the script (specially I want to know which network you are using).
2. Share the code of the deployment script.
3. Please on windows/linux use Shift+Alt+F to auto format the brownie-config.yaml (sometimes a formatting error can cause this troubles).
4. A question just out curiosity, why you set up the fee with _ never seen that syntax before.

[Nlferu]

Hello @cromewar

1. brownie run scripts/advanced_collectible/adv_deploy_and_create.py --network goerli (I was trying to verify it on rinkeby too and had same error)
2. Code below:

def main():
    adv_deploy_and_create()


def adv_deploy_and_create():
    account = get_account()
    advanced_collectible = AdvancedCollectible.deploy(
        get_contract("vrf_coordinator"),
        get_contract("link_token"),
        config["networks"][network.show_active()]["keyHash"],
        config["networks"][network.show_active()]["fee"],
        {"from": account},
        publish_source = config["networks"][network.show_active()].get("verify", False)
    )
    fund_with_link(advanced_collectible.address)
    creating_tx = advanced_collectible.createCollectible({"from": account})
    creating_tx.wait(1)
    print("New Token Has Been Created!")
    return advanced_collectible, creating_tx

3. I have installed extension and formatted code automatically for brownie-config.yaml
4. It provides same values as without _ but you as human can read it easier, for example you can check how many 0 there are much easier.

By the way this error occurs only if i add publish_source line, otherwise everything works and is deployed. I have also tried to verify lottery contract this way and it worked correct even if we are importing more things to lottery than here. My Simple Collectible contract has been verified also without problems and it is importing ERC721 also. I have tried copying contract and deploy code from repository and running it for advanced one and it throws still same error FileNotFoundError: [Errno 2] No such file or directory: 'C:\\Users\\Demos\\nft-manual\\contracts\\ERC721'

[cromewar]

This error caught me, out of the blue. I cloned the repo and I was able to deploy without problems, on the mean time please do the following.
1, delete the build folder.
2. go to your home Path (in windows should be C:/Users/yourUser) locate the .brownie folder and delete it.
3. Try to run the code again.

[Nlferu]

Hello @cromewar

I have tried what you said, but unfortunately it didn't work. I had a lot of trouble to find similar issue too, thats why I decided to ask here. I don't know how is that possible my simple collectible can find that ERC721 and advanced one can't..

[Nlferu]

@cromewar I have found issue, but have no idea how is this even possible... as issue lays in commented code! I have located problem with AdvancedCollectible.sol in below function:

Working part of code:

    function setTokenURI(uint256 tokenId, string memory _tokenURI) public {
    // pug, shiba inu, st bernard
    require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: caller is not owner or not approved");
    _setTokenURI(tokenId, _tokenURI);
    }

Code with error FileNotFoundError: [Errno 2] No such file or directory:

   function setTokenURI(uint256 tokenId, string memory _tokenURI) public {
       // We need 3 differens tokenURI's for each breed (pug, shiba inu, st bernard) and let only owner of token update token URI's
       // to do that we are going to use imported OpenZeppelin function "_isApprovedOrOwner()" from "ERC721"
       // and "_msgSender()" from https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/utils/Context.sol
       require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: caller is not token owner or approved");
       _setTokenURI(tokenId, _tokenURI);
   }

Once you remove commented lines there is no more error...

I have also figured out that error occurs with this line: // to do that we are going to use imported OpenZeppelin function "_isApprovedOrOwner()" from "ERC721" and only when when I have " marks, so using "_isApprovedOrOwner()" or "ERC721" will throw FileNotFoundError: [Errno 2] No such file or directory: 'C:\\Users\\MyUser\\Demos\\nft-test\\contracts\\ERC721' error while using "_isApprovedOrOwner()" and ERC721 will throw FileNotFoundError: [Errno 2] No such file or directory: 'C:\\Users\\MyUser\\Demos\\nft-test\\contracts\\_isApprovedOrOwned()' error. Using no "" won't cause any errors.

I don't know if it is solidity language error related and comment doesnt work as they supposed to and i have found some kind of Solidity Bug, or it is just me... If anyone has idea why that error occurs while I'm using "" in commented lines please let me know.

[Nlferu]

Hello @cromewar

Do you have any comment on that? Can you explain to me why commented lines caused the problem and how is that even possible?

[cromewar]

Well I made some research on this and I think is how the comments are managed you should use block comments and try to avoid special characters such as "" because the validation on etherscan will take those as literal expressions.

[Nlferu]

@cromewar I have tried this with block comments and issue is the same for those. The only way to avoid it is not to use "".
Anyway thank you for trying to help me on this!