Enable using Hardhat network without changing the localhost:8545 chain ID

[fvictorio]

I'm opening this issue as suggested by @rekmarks: #9827 (comment)

MetaMask comes with a localhost:8545 network, typically used for development. This network used to work fine both with ganache and with hardhat, but now MetaMask checks that the connected network has 1337 as its chainId. Since Hardhat uses 31337 as its chainId, users get an EIP-155 error when trying to use MetaMask.

The solution is to manually change the project's configuration so that 1337 is used as chainId. This causes unnecessary friction.

---

I don't know what the correct solution would be here. I think users starting a node on their localhost are knowledgeable enough, and so accepting the chain id returned by the node seems fine in that scenario (unlike manually added networks, where users could be adding by following malicious instructions). But any approach that makes MetaMask work out of the box with Hardhat would be great.

[tuler]

Another alternative is to create an additional network at MetaMask, name it localhost, use the address http://127.0.0.1:8545, and chainId 31337.

[aeither]

I got error Could not fetch chain ID. Is your RPC URL correct? when trying to create an additional network at metamask.

[praveen-palanisamy]

@aeither : Use http://0.0.0.0:8545 (instead of http://127.0.0.1:8545) as the RPC URL and try again

[IMPWNG]

@aeither : Use http://0.0.0.0:8545 (instead of http://127.0.0.1:8545) as the RPC URL and try again

That still don't work for me ..

[trozler]

Can we please fix this created unnecessary friction for developers!

[giorgosn]

Is there any progress on this issue??

[rekmarks]

Alright, we're gonna try to do something about this. I can't talk about dates or specifics yet, but hopefully in an upcoming sprint. Our hope is to effectively restore the chain ID behavior for localhost networks (and only localhost networks) to what it was prior to 8.1.0.

By way of context, the change that implemented the current behavior was introduced in version 8.1.0 of the extension, in order to resolve the security vulnerability referenced here: #9827 (comment)

Thank you for your patience and consistent feedback on this issue. We will let you know when we have more information to share, or simply close this issue when we've merged a fix.

[eniolasonowo]

We are waiting metamask?

[codingwithdidem]

Any progress?

[fvictorio]

@eniolasonowo @codingwithdidem please don't do that. We all want this to happen, but these things take time. Erik didn't mention dates for a reason. Just be patient.

[DoubleOTheven]

Would love a fix for this!

[loziniak]

@eniolasonowo @codingwithdidem please don't do that. We all want this to happen, but these things take time. Erik didn't mention dates for a reason. Just be patient.

It's probably because of Hardhat's documentation: "Please voice your support for MetaMask to fix this [...]"

[fvictorio]

@loziniak in the context of GitHub issues that means upvoting an issue to help maintainers figure out how important it is. But you're right that it could be misleading, I'll update it.

[estainit]

MetaMask! fix this

[estarossa0]

updates ?

[Addis-Belete]

Any updates??

[crazyrabbitLTC]

Still suffering with this.

[drortirosh]

Any progress on this? indeed, annoying

[HamasAli]

Any updates?

[OoXooOx]

cmon guys, do something

[luislucena16]

Hey guys! I have found a solution, you must pass directly the chainId:1337 inside the hardhat.config.js file. I have tried it and it worked for me, it stopped sending me the chainId error. I hope it works for you.

e.g

require("@nomicfoundation/hardhat-toolbox");

// The next line is part of the sample project, you don't need it in your
// project. It imports a Hardhat task definition, that can be used for
// testing the frontend.
require("./tasks/faucet");

/** @type import('hardhat/config').HardhatUserConfig */
module.exports = {
  solidity: "0.8.9",
  networks: {
    hardhat: {
      chainId: 1337 // We set 1337 to make interacting with MetaMask simpler
    }
  }
};

[luislucena16]

@Justice-Orogun review my comment

[luislucena16]

@Justice-Orogun use 31337 in your MetaMask ChainID

[Justice-Orogun]

@Justice-Orogun review my comment
I just checked.... I am still having the same issue... Didn't work out....

[Justice-Orogun]

@luislucena16
The same issue bro.... I did that before changing the ChainId to 1337.

[luislucena16]

@Justice-Orogun This is how I have mine and it works fine..

[Justice-Orogun]

@luislucena16 lemme check this out if it works from my end. Thanks for the feedback

[Justice-Orogun]

@luislucena16 this is what I have on my end.... However, lemme check out your method.

[Justice-Orogun]

@luislucena16 The same error bro.....

[luislucena16]

@Justice-Orogun I don't understand why the error is still occurring. It works fine for me

[luislucena16]

@Justice-Orogun Are you running the npx hardhat node command? Before importing the localhost?

[Justice-Orogun]

@luislucena16 I already run the npx hardhat node command

[luislucena16]

@Justice-Orogun Now try adding the localhost network

[Justice-Orogun]

@luislucena16 The same error..... I just did everything again from scratch....

[hernandp]

Same error, please fix this. This is unbelievable.

[Justice-Orogun]

@hernandp I feel this has to do with Metamask and hardhat... I am very sure there are errors somewhere around it....

[smart-tech-master]

same error

[G33kNoob]

i got working

[2023PHOENIX]

@Justice-Orogun i am using same version as you but when i switched to 0.8.16 it start working fine

[cosmic-boy0111]

that issue get solved before as I know the 31337 error and save button are not visible all things are get solved
before doing all these things run "npx hardhat node" command in your terminal and all is done

[hammad-ali18]

I want my localhost HARDHAT network to be added by calling wallet_addEthereumChain, when I am passing the chainId inside params of 31337 the calling that the function on the UI,the chainId it is showing me of 201527.
The Error is:
OnMETAMASK:
Chain ID returned by the custom network does not match the submitted chain ID.
and On Console:
inpage.js:1 MetaMask - RPC Error: Unrecognized chain ID "0x31337". Try adding the chain using wallet_addEthereumChain first. {code: -32603, message: 'Unrecognized chain ID "0x31337". Try adding the chain using wallet_addEthereumChain first.', data: {…}}

[luislucena16]

@hammad-ali18 try this:
#10290 (comment)
configure your UI to receive the chainID you set up

[SL-BLACK-EAGLE]

hi all, they these steps -

1. run the node - npx hardhat node
2. compile the contract - npx hardhat compile
3. then you have to deploy the smart contract by - 'npx hardhat run scripts/deploy.js'
4. check the terminal if successful ,
5. then you can try the metamask localhost wallet. it might fix the issue.

[GastonFavre]

With the manual configurations described in previous comments it is possible to address the problem, but it would be great if MetaMask could fix this for immediate operation with Hardahat.

[thunder1911]

does the above solutions work for sepolia too?

[luislucena16]

@thunder1911 with sepolia you have no problem!

[thunder1911]

@thunder1911 with sepolia you have no problem!

No I'm getting the same error when I'm trying to deploy my contract based on sepolia to tha localhost.

[thunder1911]

@thunder1911 with sepolia you have no problem!

Can we use the same solution given above?