feat: added explainTransaction for canton

Ticket: COIN-6230

Author: ravibitgo

modules/sdk-coin-canton/src/canton.ts

@@ -13,13 +13,23 @@ import {
   TransactionType,
   TssVerifyAddressOptions,
   VerifyTransactionOptions,
+  TransactionExplanation as BaseTransactionExplanation,
+  BaseTransaction,
 } from '@bitgo/sdk-core';
 import { auditEddsaPrivateKey } from '@bitgo/sdk-lib-mpc';
 import { BaseCoin as StaticsBaseCoin, coins } from '@bitgo/statics';
 import { TransactionBuilderFactory } from './lib';
 import { KeyPair as CantonKeyPair } from './lib/keyPair';
 import utils from './lib/utils';
 
+export interface TransactionExplanation extends BaseTransactionExplanation {
+  type: TransactionType;
+}
+
+export interface ExplainTransactionOptions {
+  txHex: string;
+}
+
 export class Canton extends BaseCoin {
   protected readonly _staticsCoin: Readonly<StaticsBaseCoin>;
 
@@ -37,6 +47,10 @@ export class Canton extends BaseCoin {
     return new Canton(bitgo, staticsCoin);
   }
 
+  private getBuilder(): TransactionBuilderFactory {
+    return new TransactionBuilderFactory(coins.get(this.getChain()));
+  }
+
   /** @inheritDoc */
   public getBaseFactor(): number {
     return 1e10;
@@ -121,6 +135,20 @@ export class Canton extends BaseCoin {
     };
   }
 
+  /** @inheritDoc */
+  explainTransaction(params: ExplainTransactionOptions): Promise<TransactionExplanation> {
+    const factory = this.getBuilder();
+    let rebuiltTransaction: BaseTransaction;
+    const txRaw = params.txHex;
+    try {
+      const txBuilder = factory.from(txRaw);
+      rebuiltTransaction = txBuilder.transaction;
+    } catch (e) {
+      throw new Error('Invalid transaction');
+    }
+    return rebuiltTransaction.explainTransaction();
+  }
+
   /** @inheritDoc */
   isValidPub(pub: string): boolean {
     return utils.isValidPublicKey(pub);

modules/sdk-coin-canton/src/lib/iface.ts

@@ -1,6 +1,16 @@
-import { TransactionType } from '@bitgo/sdk-core';
+import {
+  TransactionType,
+  TransactionExplanation as BaseTransactionExplanation,
+  ITransactionRecipient,
+} from '@bitgo/sdk-core';
 import { DamlTransaction, Metadata } from './resourcesInterface';
 
+export interface TransactionExplanation extends BaseTransactionExplanation {
+  type: TransactionType;
+  inputs?: ITransactionRecipient[];
+  inputAmount?: string;
+}
+
 /**
  * The transaction data returned from the toJson() function of a transaction
  */
@@ -9,6 +19,7 @@ export interface TxData {
   type: TransactionType;
   sender: string;
   receiver: string;
+  amount: string;
   acknowledgeData?: TransferAcknowledge;
 }
 

modules/sdk-coin-canton/src/lib/transaction/transaction.ts

@@ -1,11 +1,18 @@
-import { BaseKey, BaseTransaction, InvalidTransactionError, TransactionType } from '@bitgo/sdk-core';
+import {
+  BaseKey,
+  BaseTransaction,
+  InvalidTransactionError,
+  ITransactionRecipient,
+  TransactionType,
+} from '@bitgo/sdk-core';
 import { BaseCoin as CoinConfig } from '@bitgo/statics';
 import {
   CantonPrepareCommandResponse,
   MultiHashSignature,
   PartySignature,
   PreparedTxnParsedInfo,
   TransactionBroadcastData,
+  TransactionExplanation,
   TransferAcknowledge,
   TxData,
 } from '../iface';
@@ -127,6 +134,7 @@ export class Transaction extends BaseTransaction {
       type: this._type as TransactionType,
       sender: '',
       receiver: '',
+      amount: '',
     };
     if (this._type === TransactionType.TransferAcknowledge) {
       if (!this._acknowledgeData) {
@@ -147,6 +155,7 @@ export class Transaction extends BaseTransaction {
     }
     result.sender = parsedInfo.sender;
     result.receiver = parsedInfo.receiver;
+    result.amount = parsedInfo.amount;
     return result;
   }
 
@@ -182,4 +191,41 @@ export class Transaction extends BaseTransaction {
       throw new InvalidTransactionError('Unable to parse raw transaction data');
     }
   }
+
+  explainTransaction(): TransactionExplanation {
+    const displayOrder = [
+      'id',
+      'outputs',
+      'outputAmount',
+      'inputs',
+      'inputAmount',
+      'changeOutputs',
+      'changeAmount',
+      'fee',
+      'type',
+    ];
+    const inputs: ITransactionRecipient[] = [];
+    let inputAmount = '0';
+    switch (this.type) {
+      case TransactionType.TransferAccept:
+      case TransactionType.TransferReject: {
+        const txData = this.toJson();
+        inputs.push({ address: txData.sender, amount: txData.amount });
+        inputAmount = txData.amount;
+        break;
+      }
+    }
+    return {
+      id: this.id,
+      displayOrder,
+      outputs: [],
+      outputAmount: '0',
+      inputs: inputs,
+      inputAmount: inputAmount,
+      changeOutputs: [],
+      changeAmount: '0',
+      fee: { fee: '0' },
+      type: this.type,
+    };
+  }
 }

modules/sdk-coin-canton/src/lib/walletInitialization/walletInitTransaction.ts

@@ -4,6 +4,7 @@ import {
   MultiHashSignature,
   OnboardingTransaction,
   PreparedParty,
+  TransactionExplanation,
   WalletInitBroadcastData,
   WalletInitTxData,
 } from '../iface';
@@ -97,4 +98,18 @@ export class WalletInitTransaction extends BaseTransaction {
       throw new InvalidTransactionError('Unable to parse raw transaction data');
     }
   }
+
+  explainTransaction(): TransactionExplanation {
+    const displayOrder = ['id', 'outputs', 'outputAmount', 'changeOutputs', 'changeAmount', 'fee', 'type'];
+    return {
+      id: this.id,
+      displayOrder,
+      outputs: [],
+      outputAmount: '0',
+      changeOutputs: [],
+      changeAmount: '0',
+      fee: { fee: '0' },
+      type: this.type,
+    };
+  }
 }

modules/sdk-coin-canton/test/helper.ts

@@ -0,0 +1,6 @@
+import { coins } from '@bitgo/statics';
+import { TransactionBuilderFactory } from '../src';
+
+export function getCantonBuilderFactory(coinName: string): TransactionBuilderFactory {
+  return new TransactionBuilderFactory(coins.get(coinName));
+}

modules/sdk-coin-canton/test/integration/canton.integration.ts

@@ -0,0 +1,44 @@
+import assert from 'assert';
+
+import { TransactionType } from '@bitgo/sdk-core';
+
+import { getCantonBuilderFactory } from '../helper';
+import {
+  GenerateTopologyResponse,
+  TransferAcceptRawTransaction,
+  TransferRejectRawTransaction,
+  WalletInitRawTransaction,
+} from '../resources';
+
+describe('Canton integration tests', function () {
+  describe('Explain raw transaction', function () {
+    const factory = getCantonBuilderFactory('tcanton');
+    it('should explain raw wallet init transaction', function () {
+      const builder = factory.from(WalletInitRawTransaction);
+      const txn = builder.transaction;
+      const explainTxData = txn.explainTransaction();
+      assert(explainTxData);
+      assert.equal(explainTxData.id, GenerateTopologyResponse.multiHash);
+      assert.equal(explainTxData.type, TransactionType.WalletInitialization);
+    });
+
+    it('should explain raw transfer acceptance transaction', function () {
+      const builder = factory.from(TransferAcceptRawTransaction);
+      const txn = builder.transaction;
+      const explainTxData = txn.explainTransaction();
+      assert(explainTxData);
+      assert(explainTxData.id);
+      assert.equal(explainTxData.type, TransactionType.TransferAccept);
+      assert.equal(explainTxData.inputAmount, '5.0000000000');
+    });
+
+    it('should explain raw transfer rejection transaction', function () {
+      const builder = factory.from(TransferRejectRawTransaction);
+      const txn = builder.transaction;
+      const explainTxData = txn.explainTransaction();
+      assert(explainTxData);
+      assert.equal(explainTxData.type, TransactionType.TransferReject);
+      assert.equal(explainTxData.inputAmount, '5.0000000000');
+    });
+  });
+});

modules/sdk-coin-canton/test/resources.ts

@@ -13,6 +13,7 @@ describe('Transfer Acceptance Builder', () => {
     const txBuilder = new TransferAcceptanceBuilder(coins.get('tcanton'));
     const transferAcceptanceTx = new Transaction(coins.get('tcanton'));
     txBuilder.initBuilder(transferAcceptanceTx);
+    txBuilder.setTransaction(TransferAcceptancePrepareResponse);
     const { commandId, contractId, partyId } = TransferAcceptance;
     txBuilder.commandId(commandId).contractId(contractId).actAs(partyId);
     const requestObj: CantonTransferAcceptRejectRequest = txBuilder.toRequestObject();

modules/sdk-coin-canton/test/unit/builder/transferAccept/transferAcceptBuilder.ts

@@ -13,6 +13,7 @@ describe('Transfer Rejection Builder', () => {
     const txBuilder = new TransferRejectionBuilder(coins.get('tcanton'));
     const tx = new Transaction(coins.get('tcanton'));
     txBuilder.initBuilder(tx);
+    txBuilder.setTransaction(TransferRejectionPrepareResponse);
     const { commandId, contractId, partyId } = TransferRejection;
     txBuilder.commandId(commandId).contractId(contractId).actAs(partyId);
     const requestObj: CantonTransferAcceptRejectRequest = txBuilder.toRequestObject();