1 files changed, 47 insertions, 0 deletions
diff --git a/packages/contracts/test/utils/transaction_factory.ts b/packages/contracts/test/utils/transaction_factory.ts
new file mode 100644
index 000000000..348c0715d
--- /dev/null
+++ b/packages/contracts/test/utils/transaction_factory.ts
@@ -0,0 +1,47 @@
+import { EIP712Schema, EIP712Types, EIP712Utils, generatePseudoRandomSalt } from '@0xproject/order-utils';
+import { SignatureType } from '@0xproject/types';
+import * as ethUtil from 'ethereumjs-util';
+
+import { signingUtils } from './signing_utils';
+import { SignedTransaction } from './types';
+
+const EIP712_ZEROEX_TRANSACTION_SCHEMA: EIP712Schema = {
+    name: 'ZeroExTransaction',
+    parameters: [
+        { name: 'salt', type: EIP712Types.Uint256 },
+        { name: 'signerAddress', type: EIP712Types.Address },
+        { name: 'data', type: EIP712Types.Bytes },
+    ],
+};
+
+export class TransactionFactory {
+    private _signerBuff: Buffer;
+    private _exchangeAddress: string;
+    private _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${this._signerBuff.toString('hex')}`;
+        const executeTransactionData = {
+            salt,
+            signerAddress,
+            data,
+        };
+        const executeTransactionHashBuff = EIP712Utils.structHash(
+            EIP712_ZEROEX_TRANSACTION_SCHEMA,
+            executeTransactionData,
+        );
+        const txHash = EIP712Utils.createEIP712Message(executeTransactionHashBuff, this._exchangeAddress);
+        const signature = signingUtils.signMessage(txHash, this._privateKey, signatureType);
+        const signedTx = {
+            exchangeAddress: this._exchangeAddress,
+            signature: `0x${signature.toString('hex')}`,
+            ...executeTransactionData,
+        };
+        return signedTx;
+    }
+}