Private Key for Generated Account

[rudreshkoranne]

Hey there all!!!

I have generated an account using aptos-labs/aptos-go-sdk as such
acc1, _ := aptos.NewEd25519Account()

I want to ask how to get access of the Private Key for this generated Account.

[charlesmarvin]

I've been using the following which I lifted from aptos.NewEd25519Account() but feels like something that can (should?) be exposed by the sdk api.

pk, err := crypto.GenerateEd25519PrivateKey()
...
acc1, err := aptos.NewAccountFromSigner(pk)
...

[gregnazario]

Would love to make a new function for this, what would you like to see?

Atm, it can fairly complicated, but you can do some crafty stuff here:

acc1, _ := aptos.NewEd25519Account()
pk, ok := acc1.Signer.(*crypto.Ed25519PrivateKey)

Thinking something like:

// ExtractMessageSigner extracts the message signer from the account for
func (account *Account) ExtractMessageSigner() (crypto.MessageSigner, bool) {
	ed25519PrivKey, ok := account.Signer.(*crypto.Ed25519PrivateKey)
	if ok {
		return ed25519PrivKey, ok
	}
	singleSigner, ok := account.Signer.(*crypto.SingleSigner)
	if ok {
		return singleSigner.Signer, ok
	}
	return nil, false
}

Or alternatively can just make an "ExtractPrivateKeyString"

/ ExtractPrivateKeyString extracts the private key string
func (account *Account) ExtractPrivateKeyString() (string, error) {
	// Handle the key by itself
	ed25519PrivateKey, ok := account.Signer.(*crypto.Ed25519PrivateKey)
	if ok {
		return ed25519PrivateKey.ToAIP80()
	}
	
	// Handle key in single signer
	singleSigner, ok := account.Signer.(*crypto.SingleSigner)
	if !ok {
		innerSigner := singleSigner.Signer
		switch innerSigner.(type) {
		case *crypto.Ed25519PrivateKey:
			return innerSigner.(*crypto.Ed25519PrivateKey).ToAIP80()
		case *crypto.Secp256k1PrivateKey:
			return innerSigner.(*crypto.Secp256k1PrivateKey).ToAIP80()
		}
	}

	return "", errors.New("signer is not a private key")
}

[gregnazario]

Here's an attempt at it with some other fixes #125

[charlesmarvin]

@gregnazario 👋 I was away for a few weeks 👶 Thanks for putting up the PR. I left some comments.

[gregnazario]

I've committed with that feedback! Please reopen if it's not enough