copy dutch auction assetdata utils to @0x/order-utils

packages/contract-wrappers/src/types.ts

@@ -9,7 +9,7 @@ import {
     WETH9Events,
 } from '@0x/abi-gen-wrappers';
 import { ContractAddresses } from '@0x/contract-addresses';
-import { AssetData, OrderState, SignedOrder } from '@0x/types';
+import { OrderState, SignedOrder } from '@0x/types';
 import { BigNumber } from '@0x/utils';
 
 import { BlockParam, ContractEventArg, DecodedLogArgs, LogEntryEvent, LogWithDecodedArgs } from 'ethereum-types';
@@ -220,11 +220,7 @@ export enum DutchAuctionWrapperError {
     AssetDataMismatch = 'ASSET_DATA_MISMATCH',
 }
 
-export interface DutchAuctionData {
-    assetData: AssetData;
-    beginTimeSeconds: BigNumber;
-    beginAmount: BigNumber;
-}
+export { DutchAuctionData } from '@0x/types';
 
 export { CoordinatorServerCancellationResponse, CoordinatorServerError } from './utils/coordinator_server_types';
 

packages/order-utils/CHANGELOG.json

@@ -14,6 +14,10 @@
             {
                 "note": "Add support for encoding/decoding StaticCallProxy assetData",
                 "pr": 1863
+            },
+            {
+                "note": "Add support for encoding/decoding DutchAuction assetData",
+                "pr": 1943
             }
         ]
     },

packages/order-utils/src/asset_data_utils.ts

@@ -1,5 +1,6 @@
 import {
     AssetProxyId,
+    DutchAuctionData,
     ERC1155AssetData,
     ERC1155AssetDataNoProxyId,
     ERC20AssetData,
@@ -10,6 +11,8 @@ import {
     StaticCallAssetData,
 } from '@0x/types';
 import { AbiEncoder, BigNumber } from '@0x/utils';
+import * as ethAbi from 'ethereumjs-abi';
+import * as ethUtil from 'ethereumjs-util';
 import * as _ from 'lodash';
 
 import { constants } from './constants';
@@ -230,6 +233,59 @@ export const assetDataUtils = {
             staticCallData: decodedAssetData.staticCallData,
         };
     },
+    /**
+     * Dutch auction details are encoded with the asset data for a 0x order. This function produces a hex
+     * encoded assetData string, containing information both about the asset being traded and the
+     * dutch auction; which is usable in the makerAssetData or takerAssetData fields in a 0x order.
+     * @param assetData Hex encoded assetData string for the asset being auctioned.
+     * @param beginTimeSeconds Begin time of the dutch auction.
+     * @param beginAmount Starting amount being sold in the dutch auction.
+     * @return The hex encoded assetData string.
+     */
+    encodeDutchAuctionAssetData(assetData: string, beginTimeSeconds: BigNumber, beginAmount: BigNumber): string {
+        const assetDataBuffer = ethUtil.toBuffer(assetData);
+        const abiEncodedAuctionData = (ethAbi as any).rawEncode(
+            ['uint256', 'uint256'],
+            [beginTimeSeconds.toString(), beginAmount.toString()],
+        );
+        const abiEncodedAuctionDataBuffer = ethUtil.toBuffer(abiEncodedAuctionData);
+        const dutchAuctionDataBuffer = Buffer.concat([assetDataBuffer, abiEncodedAuctionDataBuffer]);
+        const dutchAuctionData = ethUtil.bufferToHex(dutchAuctionDataBuffer);
+        return dutchAuctionData;
+    },
+    /**
+     * Dutch auction details are encoded with the asset data for a 0x order. This function decodes a hex
+     * encoded assetData string, containing information both about the asset being traded and the
+     * dutch auction.
+     * @param dutchAuctionData Hex encoded assetData string for the asset being auctioned.
+     * @return An object containing the auction asset, auction begin time and auction begin amount.
+     */
+    decodeDutchAuctionData(dutchAuctionData: string): DutchAuctionData {
+        const dutchAuctionDataBuffer = ethUtil.toBuffer(dutchAuctionData);
+        // Decode asset data
+        const dutchAuctionDataLengthInBytes = 64;
+        const assetDataBuffer = dutchAuctionDataBuffer.slice(
+            0,
+            dutchAuctionDataBuffer.byteLength - dutchAuctionDataLengthInBytes,
+        );
+        const assetDataHex = ethUtil.bufferToHex(assetDataBuffer);
+        const assetData = assetDataUtils.decodeAssetDataOrThrow(assetDataHex);
+        // Decode auction details
+        const dutchAuctionDetailsBuffer = dutchAuctionDataBuffer.slice(
+            dutchAuctionDataBuffer.byteLength - dutchAuctionDataLengthInBytes,
+        );
+        const [beginTimeSecondsAsBN, beginAmountAsBN] = ethAbi.rawDecode(
+            ['uint256', 'uint256'],
+            dutchAuctionDetailsBuffer,
+        );
+        const beginTimeSeconds = new BigNumber(beginTimeSecondsAsBN.toString());
+        const beginAmount = new BigNumber(beginAmountAsBN.toString());
+        return {
+            assetData,
+            beginTimeSeconds,
+            beginAmount,
+        };
+    },
     /**
      * Decode and return the assetProxyId from the assetData
      * @param assetData Hex encoded assetData string to decode

packages/order-utils/test/asset_data_utils_test.ts

@@ -40,6 +40,15 @@ const KNOWN_MULTI_ASSET_ENCODING = {
         '0x94cfcdd7000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000c000000000000000000000000000000000000000000000000000000000000000030000000000000000000000000000000000000000000000000000000000000046000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000120000000000000000000000000000000000000000000000000000000000000003000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000000c000000000000000000000000000000000000000000000000000000000000001400000000000000000000000000000000000000000000000000000000000000024f47261b00000000000000000000000001dc4c1cefef38a777b15aa20260a54e584b16c48000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000044025717920000000000000000000000001dc4c1cefef38a777b15aa20260a54e584b16c480000000000000000000000000000000000000000000000000000000000000001000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000204a7cb5fb70000000000000000000000001dc4c1cefef38a777b15aa20260a54e584b16c480000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000001800000000000000000000000000000000000000000000000000000000000000003000000000000000000000000000000000000000000000000000000000000006400000000000000000000000000000000000000000000000000000000000003e90000000000000000000000000000000000000000000000000000000000002711000000000000000000000000000000000000000000000000000000000000000300000000000000000000000000000000000000000000000000000000000000c800000000000000000000000000000000000000000000000000000000000007d10000000000000000000000000000000000000000000000000000000000004e210000000000000000000000000000000000000000000000000000000000000044025717920000000000000000000000001dc4c1cefef38a777b15aa20260a54e584b16c4800000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000',
 };
 
+const KNOWN_DUTCH_AUCTION_ENCODING = {
+    tokenAddress: '0x34d402f14d58e001d8efbe6585051bf9706aa064',
+    assetData: '0xf47261b000000000000000000000000034d402f14d58e001d8efbe6585051bf9706aa064', // ERC20
+    beginTimeSeconds: new BigNumber(1562807905),
+    beginAmount: new BigNumber(5),
+    dutchAuctionAssetData:
+        '0xf47261b000000000000000000000000034d402f14d58e001d8efbe6585051bf9706aa064000000000000000000000000000000000000000000000000000000005d268e610000000000000000000000000000000000000000000000000000000000000005',
+};
+
 describe('assetDataUtils', () => {
     it('should encode ERC20', () => {
         const assetData = assetDataUtils.encodeERC20AssetData(KNOWN_ERC20_ENCODING.address);
@@ -175,4 +184,28 @@ describe('assetDataUtils', () => {
         expect(decodedErc1155AssetData2.tokenIds).to.be.deep.equal(KNOWN_ERC1155_ENCODING.tokenIds);
         expect(decodedErc1155AssetData2.callbackData).to.be.equal(KNOWN_ERC1155_ENCODING.callbackData);
     });
+    it('should encode Dutch Auction', async () => {
+        const encodedAssetData = assetDataUtils.encodeDutchAuctionAssetData(
+            KNOWN_DUTCH_AUCTION_ENCODING.assetData,
+            KNOWN_DUTCH_AUCTION_ENCODING.beginTimeSeconds,
+            KNOWN_DUTCH_AUCTION_ENCODING.beginAmount,
+        );
+        expect(encodedAssetData).to.be.equal(KNOWN_DUTCH_AUCTION_ENCODING.dutchAuctionAssetData);
+    });
+    it('should decode Dutch Auction', async () => {
+        const { assetData, beginTimeSeconds, beginAmount } = assetDataUtils.decodeDutchAuctionData(
+            KNOWN_DUTCH_AUCTION_ENCODING.dutchAuctionAssetData,
+        );
+
+        const { assetProxyId, tokenAddress } = assetDataUtils.decodeERC20AssetData(
+            KNOWN_DUTCH_AUCTION_ENCODING.assetData,
+        );
+
+        // tslint:disable:no-unnecessary-type-assertion
+        expect((assetData as ERC20AssetData).assetProxyId).to.be.equal(assetProxyId);
+        expect((assetData as ERC20AssetData).tokenAddress).to.be.equal(tokenAddress);
+        // tslint:enable:no-unnecessary-type-assertion
+        expect(beginTimeSeconds).to.deep.equal(KNOWN_DUTCH_AUCTION_ENCODING.beginTimeSeconds);
+        expect(beginAmount).to.deep.equal(KNOWN_DUTCH_AUCTION_ENCODING.beginAmount);
+    });
 });

packages/types/src/index.ts

@@ -216,6 +216,12 @@ export interface MultiAssetDataWithRecursiveDecoding {
     nestedAssetData: SingleAssetData[];
 }
 
+export interface DutchAuctionData {
+    assetData: AssetData;
+    beginTimeSeconds: BigNumber;
+    beginAmount: BigNumber;
+}
+
 export type AssetData = SingleAssetData | MultiAssetData | MultiAssetDataWithRecursiveDecoding;
 
 // TODO: DRY. These should be extracted from contract code.