Question: Fetching Certificates for Device

[devrajsinghrawat]

When we need to fetch Certificates for Device , We are using the helper function from CertificateUtils

CertificateUtils.getAllOwnedCertificates(blockchainProperties)

where in blockchainProperties, we need to set the active user, which is a wallet instance, To get this wallet instance we need to pass the private keys

export interface IBlockchainProperties {
    web3: providers.FallbackProvider | providers.JsonRpcProvider;
    registry: Registry;
    issuer: Issuer;
    activeUser?: Signer;
}

So Is there any other way to fetch the Device certificate, without exposing the device private key?

[josipbagaric]

Sure, the activeUser is an optional parameter (hence the question mark in activeUser?).

You should be able to get details about the certificate even without the activeUser property, but you won't be able to trigger actions such as .transfer(), .claim() etc. because they require sending a transaction to the blockchain.

[devrajsinghrawat]

Hi @JosephBagaric many thanks for your reply ..

Agree that, we can get owned Certificate data without pk of active user.

But for transfer ,

We do need to the Certificate instane

Const [certificate] = await CertificateUtils.getAllOwnedCertificates(blockchainProperties);
this to get this instance we also need to set activeUser like you have mentioned

later this instance are being used for initiate transfer
await certificate.transfer(deviceOwnerWallet.address, totalVolume)

Now, is it possible if we can get this signing part using HCM and then send the signed transaction instead using raw PK.

[josipbagaric]

activeUser is of type Signer, meaning that we support any Ethers.js compatible Signer module (private key, MetaMask, etc.). Doesn't have to be a raw PK.

There's currently no support to send a signed raw transaction to the Certificate facade to execute .transfer() or .claim().
It's only done through the Ethers.js Signer object.

Can you create a custom Signer module for HCM and use that? That should work.

[devrajsinghrawat]

Do we have any direction for creating a custom Signer module and how that module will be integrated into Origin operations

[josipbagaric]

Sure, probably you can just create a TypeScript implementation of the abstract Signer interface from ethers.js.
https://github.com/ethers-io/ethers.js/tree/master/packages/abstract-signer

Then just attach this Signer object to blockchainProperties.activeUser in Origin and it should work out-of-the-box.

I'm not familiar with HCM and how it works, so I can't help you on that part.

[devrajsinghrawat]

Thanks @JosephBagaric for your prompt inputs .. Let me explore on this