State transition SDK for agents

[mareksepp]

[b3y0urs3lf]

While creating this SDK, please also add examples of SDK functionality.

But please add it in same repo, so when change to SDK will be introduced, then example can be updated right away, and there wont be desynchronization. Thanks

Expected result: add examples in SDK repo right away.

[b3y0urs3lf]

Latest versions related to testing activities were using aggregator on https://gateway-test.unicity.network with commit 13765be and sdk commit commit 07136a4cf61978145fdc7cedc75b20124fb4843f.

Within testing activities it seems I were able to perform all the specified flows in https://github.com/unicitynetwork/state-transition-sdk/blob/e4a1eabdffd453f02f78971a4451e54755544854/README.md

A[Start]
A --> B[Recipient Generates Address]
With MaskedPredicate like:

const recipientPredicate = await MaskedPredicate.create(
    token.id,
    token.type,
    signingservice,
    HashAlgorithm.SHA256,
    nonce,
  );
recipientPredicate.reference

or differently like:

const recipientSigningService = await SigningService.createFromSecret(receiverSecret, receiverNonce);
 const reference = await MaskedPredicate.calculateReference(
        splitTokens[0].type,
        "secp256k1",
        recipientSigningService.publicKey,
        HashAlgorithm.SHA256,
        receiverNonce
    );
    const recipientAddress = await DirectAddress.create(reference);

B --> C[Recipient Shares Address with Sender]
C --> D[Sender Submits Transaction Commitment]

const sendTokenTx = await sendToken(
      client,
      token,
      await SigningService.createFromSecret(ownerSecret, token.state.unlockPredicate.nonce),
     recipientAddress
    );

D --> E[Sender Retrieves Inclusion Proof]
client.createTransaction(commitment, await **waitInclusionProof**(client, commitment));
E --> F[Sender Creates Transaction]
F --> G[Sender Sends Transaction and Token to Recipient]
const tokenJson = exportFlow(splitTokens[0], sendTokenTx, true);
G --> H[Recipient Imports Token and Transaction]

const receiverImportedToken = await new TokenFactory(new PredicateFactory()).create(
      JSON.parse(tokenJson).token,
      TestTokenData.fromJSON
    );

const importedTransaction = await Transaction.fromJSON(
            receiverImportedToken.id,
            receiverImportedToken.type,
            JSON.parse(tokenJson).transaction as ITransactionJson<ITransactionDataJson>,
            new PredicateFactory(),
        );

H --> I[Recipient Verifies Transaction]
I --> J[Recipient Finishes Transaction]

const maskedPredicate = await MaskedPredicate.create(
        receiverImportedToken.id,
        receiverImportedToken.type,
        recipientSigningService,
        HashAlgorithm.SHA256,
        receiverNonce,
    );

    // Finish the transaction with the recipient predicate
    const updateToken = await client.finishTransaction(
      receiverImportedToken,
      await TokenState.create(
          maskedPredicate,
          textEncoder.encode('my custom data')
      ),
      importedTransaction,
    );

Moving task to done.