Introduce Signer interface for key management (breaking changes, moving to SDK 2.0)

[netoneko]

Before:

const sender = Orbs.createAccount();
const receiver = Orbs.createAccount();
const orbsClient = new Orbs.Client(endpoint, virtualChainId, "TEST_NET");

const [tx, txId] = orbsClient.createTransaction(
  sender.publicKey, sender.privateKey, // removed in 2.0
  "BenchmarkToken", "transfer", 
  [Orbs.argUint64(10), Orbs.argAddress(receiver.address)]);

const query = orbsClient.createQuery(sender.publicKey, 
"BenchmarkToken", "getBalance", 
[Orbs.argAddress(receiver.address)]);

After:

const sender = Orbs.createAccount();
const receiver = Orbs.createAccount();
const senderClient = new Orbs.Client(endpoint, virtualChainId, "TEST_NET", 
  new Orbs.DefaultSigner(sender)); // added in 2.0

const [tx, txId] = await senderClient.createTransaction("BenchmarkToken", "transfer", 
  [Orbs.argUint64(10), Orbs.argAddress(receiver.address)]); // became async in 2.0

const query = await senderClient.createQuery("BenchmarkToken", "getBalance", 
  [Orbs.argAddress(receiver.address)]); // became async in 2.0

Notice that references to publicKey and privateKey were removed and instead you have to pass new DefaultSigner({publicKey, privateKey}) which encapsulates signing.

The purpose of this change is to be able to inject the signer from the outside without exposing the keys, a step forward to implementing a wallet like Metamask.

[electricmonk]

My only qualm is around the DefaultSigner name - can we name it LocalSigner instead? or a different name that reflects what distinguishes it from other future signers?

[gilamran]

I agree with Shay, DefaultSigner is too general. I also like the LocalSigner.

[gilamran]

The file Signature can be better described by calling it Signer instead.

[gilamran]

I don't understand the why you erased the contracts clone, and used a local versions of it (input.json and output.json). Without the clone you might miss changes

[gilamran]

These lines were just moved, right?

[netoneko]

Yeah. I just moved to async/await syntax.

[netoneko]

I have removed the contracts clone because it's not really compatible with the old format anymore (because keys moved to a different place in the config as they are not parameters of the calls anymore).

We won't miss the changes because we run this e2e against gamma, so there is no difference if the input jsons come from outside or are stored here and can be refactored.

[netoneko]

I believe I have resolved all the issues.

[gilamran]

Great job!!