1 files changed, 46 insertions, 0 deletions
diff --git a/packages/order-utils/src/transaction_hash.ts b/packages/order-utils/src/transaction_hash.ts
new file mode 100644
index 000000000..2b2345af7
--- /dev/null
+++ b/packages/order-utils/src/transaction_hash.ts
@@ -0,0 +1,46 @@
+import { schemas, SchemaValidator } from '@0x/json-schemas';
+import { SignedZeroExTransaction, ZeroExTransaction } from '@0x/types';
+import { signTypedDataUtils } from '@0x/utils';
+import * as _ from 'lodash';
+
+import { assert } from './assert';
+import { eip712Utils } from './eip712_utils';
+
+export const transactionHashUtils = {
+    /**
+     * Checks if the supplied hex encoded 0x transaction hash is valid.
+     * Note: Valid means it has the expected format, not that a transaction with the transactionHash exists.
+     * Use this method when processing transactionHashes submitted as user input.
+     * @param   transactionHash    Hex encoded transactionHash.
+     * @return  Whether the supplied transactionHash has the expected format.
+     */
+    isValidTransactionHash(transactionHash: string): boolean {
+        // Since this method can be called to check if any arbitrary string conforms to an transactionHash's
+        // format, we only assert that we were indeed passed a string.
+        assert.isString('transactionHash', transactionHash);
+        const schemaValidator = new SchemaValidator();
+        const isValid = schemaValidator.validate(transactionHash, schemas.orderHashSchema).valid;
+        return isValid;
+    },
+    /**
+     * Computes the transactionHash for a supplied 0x transaction.
+     * @param   transaction   An object that conforms to the ZeroExTransaction or SignedZeroExTransaction interface definitions.
+     * @return  Hex encoded string transactionHash from hashing the supplied order.
+     */
+    getTransactionHashHex(transaction: ZeroExTransaction | SignedZeroExTransaction): string {
+        assert.doesConformToSchema('transaction', transaction, schemas.zeroExTransactionSchema, [schemas.hexSchema]);
+        const transactionHashBuff = transactionHashUtils.getTransactionHashBuffer(transaction);
+        const transactionHashHex = `0x${transactionHashBuff.toString('hex')}`;
+        return transactionHashHex;
+    },
+    /**
+     * Computes the transactionHash for a supplied 0x transaction.
+     * @param   transaction   An object that conforms to the ZeroExTransaction or SignedZeroExTransaction interface definitions.
+     * @return  A Buffer containing the resulting transactionHash from hashing the supplied 0x transaction.
+     */
+    getTransactionHashBuffer(transaction: ZeroExTransaction | SignedZeroExTransaction): Buffer {
+        const typedData = eip712Utils.createZeroExTransactionTypedData(transaction);
+        const transactionHashBuff = signTypedDataUtils.generateTypedDataHash(typedData);
+        return transactionHashBuff;
+    },
+};