Add order parsers to order-util

packages/order-utils/src/index.ts

@@ -6,6 +6,7 @@ export { eip712Utils } from './eip712_utils';
 export { marketUtils } from './market_utils';
 export { rateUtils } from './rate_utils';
 export { sortingUtils } from './sorting_utils';
+export { orderParsingUtils } from './parsing_utils';
 
 export { OrderStateUtils } from './order_state_utils';
 export { AbstractBalanceAndProxyAllowanceFetcher } from './abstract/abstract_balance_and_proxy_allowance_fetcher';
@@ -45,4 +46,4 @@ export {
     FindOrdersThatCoverMakerAssetFillAmountOpts,
     FeeOrdersAndRemainingFeeAmount,
     OrdersAndRemainingFillAmount,
-} from './types';
+} from './types';

packages/order-utils/src/parsing_utils.ts

@@ -0,0 +1,27 @@
+import { BigNumber } from '@0xproject/utils';
+import * as _ from 'lodash';
+
+export const orderParsingUtils = {
+    convertStringsFieldsToBigNumbers(obj: any, fields: string[]): any {
+        const result = _.assign({}, obj);
+        _.each(fields, field => {
+            _.update(result, field, (value: string) => {
+                if (_.isUndefined(value)) {
+                    throw new Error(`Could not find field '${field}' while converting string fields to BigNumber.`);
+                }
+                return new BigNumber(value);
+            });
+        });
+        return result;
+    },
+    convertOrderStringFieldsToBigNumber(order: any): any {
+        return orderParsingUtils.convertStringsFieldsToBigNumbers(order, [
+            'makerAssetAmount',
+            'takerAssetAmount',
+            'makerFee',
+            'takerFee',
+            'expirationTimeSeconds',
+            'salt',
+        ]);
+    }
+}