1 files changed, 37 insertions, 0 deletions
diff --git a/contracts/test-utils/src/transaction_factory.ts b/contracts/test-utils/src/transaction_factory.ts
new file mode 100644
index 000000000..dbab3ade4
--- /dev/null
+++ b/contracts/test-utils/src/transaction_factory.ts
@@ -0,0 +1,37 @@
+import { eip712Utils, generatePseudoRandomSalt } from '@0x/order-utils';
+import { SignatureType } from '@0x/types';
+import { signTypedDataUtils } from '@0x/utils';
+import * as ethUtil from 'ethereumjs-util';
+
+import { signingUtils } from './signing_utils';
+import { SignedTransaction } from './types';
+
+export class TransactionFactory {
+    private readonly _signerBuff: Buffer;
+    private readonly _exchangeAddress: string;
+    private readonly _privateKey: Buffer;
+    constructor(privateKey: Buffer, exchangeAddress: string) {
+        this._privateKey = privateKey;
+        this._exchangeAddress = exchangeAddress;
+        this._signerBuff = ethUtil.privateToAddress(this._privateKey);
+    }
+    public newSignedTransaction(data: string, signatureType: SignatureType = SignatureType.EthSign): SignedTransaction {
+        const salt = generatePseudoRandomSalt();
+        const signerAddress = `0x${this._signerBuff.toString('hex')}`;
+        const executeTransactionData = {
+            salt,
+            signerAddress,
+            data,
+        };
+
+        const typedData = eip712Utils.createZeroExTransactionTypedData(executeTransactionData, this._exchangeAddress);
+        const eip712MessageBuffer = signTypedDataUtils.generateTypedDataHash(typedData);
+        const signature = signingUtils.signMessage(eip712MessageBuffer, this._privateKey, signatureType);
+        const signedTx = {
+            exchangeAddress: this._exchangeAddress,
+            signature: `0x${signature.toString('hex')}`,
+            ...executeTransactionData,
+        };
+        return signedTx;
+    }
+}