Allow multiple exchange versions t be functional at the same time

4 files changed, 127 insertions, 52 deletions

diff --git a/src/0x.ts b/src/0x.ts
index d7a01ba70..472a55102 100644
--- a/src/0x.ts
+++ b/src/0x.ts
@@ -16,7 +16,6 @@ import {EtherTokenWrapper} from './contract_wrappers/ether_token_wrapper';
 import {ecSignatureSchema} from './schemas/ec_signature_schema';
 import {TokenWrapper} from './contract_wrappers/token_wrapper';
 import {ECSignature, ZeroExError, Order, SignedOrder, Web3Provider} from './types';
-import * as ExchangeArtifacts from './artifacts/Exchange.json';
 import {orderSchema} from './schemas/order_schemas';
 
 // Customize our BigNumber instances
@@ -179,9 +178,7 @@ export class ZeroEx {
      */
     public async getOrderHashHexAsync(order: Order|SignedOrder): Promise<string> {
         assert.doesConformToSchema('order', order, orderSchema);
-
-        const exchangeContractAddr = await this._getExchangeAddressAsync();
-        const orderHashHex = utils.getOrderHashHex(order, exchangeContractAddr);
+        const orderHashHex = utils.getOrderHashHex(order, order.exchangeContractAddress);
         return orderHashHex;
     }
     /**
diff --git a/src/contract_wrappers/exchange_wrapper.ts b/src/contract_wrappers/exchange_wrapper.ts
index 622b937c2..6138d4ce9 100644
--- a/src/contract_wrappers/exchange_wrapper.ts
+++ b/src/contract_wrappers/exchange_wrapper.ts
@@ -7,6 +7,7 @@ import {
     ExchangeContract,
     ExchangeContractErrCodes,
     ExchangeContractErrs,
+    ZeroExError,
     OrderValues,
     OrderAddresses,
     Order,
@@ -25,11 +26,13 @@ import {
     LogErrorContractEventArgs,
     LogFillContractEventArgs,
     LogCancelContractEventArgs,
+    ExchangeContractByAddress,
+    ContractArtifact,
 } from '../types';
 import {assert} from '../utils/assert';
 import {utils} from '../utils/utils';
 import {ContractWrapper} from './contract_wrapper';
-import * as ExchangeArtifacts from '../artifacts/exchange/Exchange.json';
+import {ExchangeArtifactsByName} from '../exchange_artifacts_by_name';
 import {ecSignatureSchema} from '../schemas/ec_signature_schema';
 import {signedOrdersSchema} from '../schemas/signed_orders_schema';
 import {orderFillRequestsSchema} from '../schemas/order_fill_requests_schema';
@@ -53,7 +56,7 @@ export class ExchangeWrapper extends ContractWrapper {
         [ExchangeContractErrCodes.ERROR_FILL_TRUNCATION]: ExchangeContractErrs.ORDER_FILL_ROUNDING_ERROR,
         [ExchangeContractErrCodes.ERROR_FILL_BALANCE_ALLOWANCE]: ExchangeContractErrs.FILL_BALANCE_ALLOWANCE_ERROR,
     };
-    private _exchangeContractIfExists?: ExchangeContract;
+    private _exchangeContractByAddress: ExchangeContractByAddress;
     private _exchangeLogEventEmitters: ContractEventEmitter[];
     private _tokenWrapper: TokenWrapper;
     private static _getOrderAddressesAndValues(order: Order): [OrderAddresses, OrderValues] {
@@ -78,23 +81,26 @@ export class ExchangeWrapper extends ContractWrapper {
         super(web3Wrapper);
         this._tokenWrapper = tokenWrapper;
         this._exchangeLogEventEmitters = [];
+        this._exchangeContractByAddress = {};
     }
     public async invalidateContractInstanceAsync(): Promise<void> {
         await this.stopWatchingAllEventsAsync();
-        delete this._exchangeContractIfExists;
+        this._exchangeContractByAddress = {};
     }
     /**
      * Returns the unavailable takerAmount of an order. Unavailable amount is defined as the total
      * amount that has been filled or cancelled. The remaining takerAmount can be calculated by
      * subtracting the unavailable amount from the total order takerAmount.
-     * @param   orderHash    The hex encoded orderHash for which you would like to retrieve the
-     *                       unavailable takerAmount.
+     * @param   orderHash               The hex encoded orderHash for which you would like to retrieve the
+     *                                  unavailable takerAmount.
+     * @param   exchangeContractAddress The hex encoded address of the Exchange contract to use.
      * @return  The amount of the order (in taker tokens) that has either been filled or canceled.
      */
-    public async getUnavailableTakerAmountAsync(orderHash: string): Promise<BigNumber.BigNumber> {
+    public async getUnavailableTakerAmountAsync(orderHash: string,
+                                                exchangeContractAddress: string): Promise<BigNumber.BigNumber> {
         assert.isValidOrderHash('orderHash', orderHash);
 
-        const exchangeContract = await this._getExchangeContractAsync();
+        const exchangeContract = await this._getExchangeContractAsync(exchangeContractAddress);
         let unavailableAmountInBaseUnits = await exchangeContract.getUnavailableValueT.call(orderHash);
         // Wrap BigNumbers returned from web3 with our own (later) version of BigNumber
         unavailableAmountInBaseUnits = new BigNumber(unavailableAmountInBaseUnits);
@@ -103,12 +109,14 @@ export class ExchangeWrapper extends ContractWrapper {
     /**
      * Retrieve the takerAmount of an order that has already been filled.
      * @param   orderHash    The hex encoded orderHash for which you would like to retrieve the filled takerAmount.
+     * @param   exchangeContractAddress The hex encoded address of the Exchange contract to use.
      * @return  The amount of the order (in taker tokens) that has already been filled.
      */
-    public async getFilledTakerAmountAsync(orderHash: string): Promise<BigNumber.BigNumber> {
+    public async getFilledTakerAmountAsync(orderHash: string,
+                                           exchangeContractAddress: string): Promise<BigNumber.BigNumber> {
         assert.isValidOrderHash('orderHash', orderHash);
 
-        const exchangeContract = await this._getExchangeContractAsync();
+        const exchangeContract = await this._getExchangeContractAsync(exchangeContractAddress);
         let fillAmountInBaseUnits = await exchangeContract.filled.call(orderHash);
         // Wrap BigNumbers returned from web3 with our own (later) version of BigNumber
         fillAmountInBaseUnits = new BigNumber(fillAmountInBaseUnits);
@@ -118,12 +126,14 @@ export class ExchangeWrapper extends ContractWrapper {
      * Retrieve the takerAmount of an order that has been cancelled.
      * @param   orderHash    The hex encoded orderHash for which you would like to retrieve the
      *                       cancelled takerAmount.
+     * @param   exchangeContractAddress The hex encoded address of the Exchange contract to use.
      * @return  The amount of the order (in taker tokens) that has been cancelled.
      */
-    public async getCanceledTakerAmountAsync(orderHash: string): Promise<BigNumber.BigNumber> {
+    public async getCanceledTakerAmountAsync(orderHash: string,
+                                             exchangeContractAddress: string): Promise<BigNumber.BigNumber> {
         assert.isValidOrderHash('orderHash', orderHash);
 
-        const exchangeContract = await this._getExchangeContractAsync();
+        const exchangeContract = await this._getExchangeContractAsync(exchangeContractAddress);
         let cancelledAmountInBaseUnits = await exchangeContract.cancelled.call(orderHash);
         // Wrap BigNumbers returned from web3 with our own (later) version of BigNumber
         cancelledAmountInBaseUnits = new BigNumber(cancelledAmountInBaseUnits);
@@ -152,7 +162,7 @@ export class ExchangeWrapper extends ContractWrapper {
         assert.isBoolean('shouldCheckTransfer', shouldCheckTransfer);
         await assert.isSenderAddressAsync('takerAddress', takerAddress, this._web3Wrapper);
 
-        const exchangeInstance = await this._getExchangeContractAsync();
+        const exchangeInstance = await this._getExchangeContractAsync(signedOrder.exchangeContractAddress);
         await this._validateFillOrderAndThrowIfInvalidAsync(signedOrder, takerTokenFillAmount, takerAddress);
 
         const [orderAddresses, orderValues] = ExchangeWrapper._getOrderAddressesAndValues(signedOrder);
@@ -207,7 +217,10 @@ export class ExchangeWrapper extends ContractWrapper {
                                      shouldCheckTransfer: boolean, takerAddress: string): Promise<BigNumber.BigNumber> {
         const takerTokenAddresses = _.map(signedOrders, signedOrder => signedOrder.takerTokenAddress);
         assert.hasAtMostOneUniqueValue(takerTokenAddresses,
-                                        ExchangeContractErrs.MULTIPLE_TAKER_TOKENS_IN_FILL_UP_TO_DISALLOWED);
+                                       ExchangeContractErrs.MULTIPLE_TAKER_TOKENS_IN_FILL_UP_TO_DISALLOWED);
+        const exchangeContractAddresses = _.map(signedOrders, signedOrder => signedOrder.exchangeContractAddress);
+        assert.hasAtMostOneUniqueValue(exchangeContractAddresses,
+                                       ExchangeContractErrs.BATCH_ORDERS_MUST_HAVE_SAME_EXCHANGE_ADDRESS);
         assert.isBigNumber('takerTokenFillAmount', takerTokenFillAmount);
         assert.isBoolean('shouldCheckTransfer', shouldCheckTransfer);
         assert.doesConformToSchema('signedOrders', signedOrders, signedOrdersSchema);
@@ -233,7 +246,7 @@ export class ExchangeWrapper extends ContractWrapper {
             orderAddressesValuesAndSignatureArray,
         );
 
-        const exchangeInstance = await this._getExchangeContractAsync();
+        const exchangeInstance = await this._getExchangeContractAsync(exchangeContractAddresses[0]);
         const gas = await exchangeInstance.fillUpTo.estimateGas(
             orderAddressesArray,
             orderValuesArray,
@@ -282,6 +295,12 @@ export class ExchangeWrapper extends ContractWrapper {
     @decorators.contractCallErrorHandler
     public async batchFillOrderAsync(orderFillRequests: OrderFillRequest[],
                                      shouldCheckTransfer: boolean, takerAddress: string): Promise<void> {
+        const exchangeContractAddresses = _.map(
+            orderFillRequests,
+            orderFillRequest => orderFillRequest.signedOrder.exchangeContractAddress,
+        );
+        assert.hasAtMostOneUniqueValue(exchangeContractAddresses,
+                                       ExchangeContractErrs.BATCH_ORDERS_MUST_HAVE_SAME_EXCHANGE_ADDRESS);
         assert.isBoolean('shouldCheckTransfer', shouldCheckTransfer);
         await assert.isSenderAddressAsync('takerAddress', takerAddress, this._web3Wrapper);
         assert.doesConformToSchema('orderFillRequests', orderFillRequests, orderFillRequestsSchema);
@@ -307,7 +326,7 @@ export class ExchangeWrapper extends ContractWrapper {
             orderAddressesValuesAmountsAndSignatureArray,
         );
 
-        const exchangeInstance = await this._getExchangeContractAsync();
+        const exchangeInstance = await this._getExchangeContractAsync(exchangeContractAddresses[0]);
         const gas = await exchangeInstance.batchFill.estimateGas(
             orderAddressesArray,
             orderValuesArray,
@@ -351,7 +370,7 @@ export class ExchangeWrapper extends ContractWrapper {
         assert.isBigNumber('takerTokenFillAmount', takerTokenFillAmount);
         await assert.isSenderAddressAsync('takerAddress', takerAddress, this._web3Wrapper);
 
-        const exchangeInstance = await this._getExchangeContractAsync();
+        const exchangeInstance = await this._getExchangeContractAsync(signedOrder.exchangeContractAddress);
         await this._validateFillOrderAndThrowIfInvalidAsync(signedOrder, takerTokenFillAmount, takerAddress);
 
         await this._validateFillOrKillOrderAndThrowIfInvalidAsync(signedOrder, exchangeInstance.address,
@@ -394,9 +413,18 @@ export class ExchangeWrapper extends ContractWrapper {
     @decorators.contractCallErrorHandler
     public async batchFillOrKillAsync(orderFillOrKillRequests: OrderFillOrKillRequest[],
                                       takerAddress: string): Promise<void> {
+        const exchangeContractAddresses = _.map(
+            orderFillOrKillRequests,
+            orderFillOrKillRequest => orderFillOrKillRequest.signedOrder.exchangeContractAddress,
+        );
+        assert.hasAtMostOneUniqueValue(exchangeContractAddresses,
+                                       ExchangeContractErrs.BATCH_ORDERS_MUST_HAVE_SAME_EXCHANGE_ADDRESS);
         await assert.isSenderAddressAsync('takerAddress', takerAddress, this._web3Wrapper);
         assert.doesConformToSchema('orderFillOrKillRequests', orderFillOrKillRequests, orderFillOrKillRequestsSchema);
-        const exchangeInstance = await this._getExchangeContractAsync();
+        if (_.isEmpty(orderFillOrKillRequests)) {
+            return; // no-op
+        }
+        const exchangeInstance = await this._getExchangeContractAsync(exchangeContractAddresses[0]);
         for (const request of orderFillOrKillRequests) {
             await this._validateFillOrKillOrderAndThrowIfInvalidAsync(request.signedOrder, exchangeInstance.address,
                                                                      request.fillTakerAmount);
@@ -455,7 +483,7 @@ export class ExchangeWrapper extends ContractWrapper {
         assert.isBigNumber('takerTokenCancelAmount', takerTokenCancelAmount);
         await assert.isSenderAddressAsync('order.maker', order.maker, this._web3Wrapper);
 
-        const exchangeInstance = await this._getExchangeContractAsync();
+        const exchangeInstance = await this._getExchangeContractAsync(order.exchangeContractAddress);
         await this._validateCancelOrderAndThrowIfInvalidAsync(order, takerTokenCancelAmount);
 
         const [orderAddresses, orderValues] = ExchangeWrapper._getOrderAddressesAndValues(order);
@@ -489,6 +517,12 @@ export class ExchangeWrapper extends ContractWrapper {
      */
     @decorators.contractCallErrorHandler
     public async batchCancelOrderAsync(orderCancellationRequests: OrderCancellationRequest[]): Promise<void> {
+        const exchangeContractAddresses = _.map(
+            orderCancellationRequests,
+            orderCancellationRequest => orderCancellationRequest.order.exchangeContractAddress,
+        );
+        assert.hasAtMostOneUniqueValue(exchangeContractAddresses,
+                                       ExchangeContractErrs.BATCH_ORDERS_MUST_HAVE_SAME_EXCHANGE_ADDRESS);
         const makers = _.map(orderCancellationRequests, cancellationRequest => cancellationRequest.order.maker);
         assert.hasAtMostOneUniqueValue(makers, ExchangeContractErrs.MULTIPLE_MAKERS_IN_SINGLE_CANCEL_BATCH_DISALLOWED);
         const maker = makers[0];
@@ -503,7 +537,7 @@ export class ExchangeWrapper extends ContractWrapper {
         if (_.isEmpty(orderCancellationRequests)) {
             return; // no-op
         }
-        const exchangeInstance = await this._getExchangeContractAsync();
+        const exchangeInstance = await this._getExchangeContractAsync(exchangeContractAddresses[0]);
         const orderAddressesValuesAndTakerTokenCancelAmounts = _.map(orderCancellationRequests, cancellationRequest => {
             return [
                 ...ExchangeWrapper._getOrderAddressesAndValues(cancellationRequest.order),
@@ -534,16 +568,17 @@ export class ExchangeWrapper extends ContractWrapper {
     }
     /**
      * Subscribe to an event type emitted by the Exchange smart contract
-     * @param   eventName           The exchange contract event you would like to subscribe to.
-     * @param   subscriptionOpts    Subscriptions options that let you configure the subscription.
-     * @param   indexFilterValues   An object where the keys are indexed args returned by the event and
-     *                              the value is the value you are interested in. E.g `{maker: aUserAddressHex}`
+     * @param   eventName               The exchange contract event you would like to subscribe to.
+     * @param   subscriptionOpts        Subscriptions options that let you configure the subscription.
+     * @param   indexFilterValues       An object where the keys are indexed args returned by the event and
+     *                                  the value is the value you are interested in. E.g `{maker: aUserAddressHex}`
+     * @param   exchangeContractAddress The hex encoded address of the Exchange contract to use.
      * @return                      ContractEventEmitter object
      */
     public async subscribeAsync(eventName: ExchangeEvents, subscriptionOpts: SubscriptionOpts,
-                                indexFilterValues: IndexedFilterValues):
+                                indexFilterValues: IndexedFilterValues, exchangeContractAddress: string):
                                 Promise<ContractEventEmitter> {
-        const exchangeContract = await this._getExchangeContractAsync();
+        const exchangeContract = await this._getExchangeContractAsync(exchangeContractAddress);
         let createLogEvent: CreateContractEvent;
         switch (eventName) {
             case ExchangeEvents.LogFill:
@@ -565,13 +600,21 @@ export class ExchangeWrapper extends ContractWrapper {
         return eventEmitter;
     }
     /**
-     * Returns the ethereum address of the current exchange contract
+     * Returns the ethereum addresses of all available exchange contracts
      * on the network that the provided web3 instance is connected to
-     * @return  The ethereum address of the current exchange contract.
+     * @return  The ethereum addresses of all available exchange contract.
      */
-    public async getContractAddressAsync(): Promise<string> {
-       const exchangeContract = await this._getExchangeContractAsync();
-       return exchangeContract.address;
+    public async getAvailableContractAddressedAsync(): Promise<string[]> {
+        const networkId = await this._web3Wrapper.getNetworkIdIfExistsAsync();
+        if (_.isUndefined(networkId)) {
+            return [];
+        } else {
+            const exchangeAddresses = _.map(
+                _.values(ExchangeArtifactsByName),
+                exchangeArfifact => exchangeArfifact.networks[networkId].address,
+            );
+            return exchangeAddresses;
+        }
     }
     /**
      * Stops watching for all exchange events
@@ -592,12 +635,13 @@ export class ExchangeWrapper extends ContractWrapper {
         return zeroExEvent;
     }
     private async _isValidSignatureUsingContractCallAsync(dataHex: string, ecSignature: ECSignature,
-                                                          signerAddressHex: string): Promise<boolean> {
+                                                          signerAddressHex: string,
+                                                          exchangeContractAddress: string): Promise<boolean> {
         assert.isHexString('dataHex', dataHex);
         assert.doesConformToSchema('ecSignature', ecSignature, ecSignatureSchema);
         assert.isETHAddressHex('signerAddressHex', signerAddressHex);
 
-        const exchangeInstance = await this._getExchangeContractAsync();
+        const exchangeInstance = await this._getExchangeContractAsync(exchangeContractAddress);
 
         const isValidSignature = await exchangeInstance.isValidSignature.call(
             signerAddressHex,
@@ -609,12 +653,12 @@ export class ExchangeWrapper extends ContractWrapper {
         return isValidSignature;
     }
     private async _getOrderHashHexAsync(order: Order|SignedOrder): Promise<string> {
-        const exchangeInstance = await this._getExchangeContractAsync();
+        const exchangeInstance = await this._getExchangeContractAsync(order.exchangeContractAddress);
         const orderHashHex = utils.getOrderHashHex(order, exchangeInstance.address);
         return orderHashHex;
     }
     private async _getOrderHashHexUsingContractCallAsync(order: Order|SignedOrder): Promise<string> {
-        const exchangeInstance = await this._getExchangeContractAsync();
+        const exchangeInstance = await this._getExchangeContractAsync(order.exchangeContractAddress);
         const [orderAddresses, orderValues] = ExchangeWrapper._getOrderAddressesAndValues(order);
         const orderHashHex = await exchangeInstance.getOrderHash.call(orderAddresses, orderValues);
         return orderHashHex;
@@ -632,12 +676,13 @@ export class ExchangeWrapper extends ContractWrapper {
         if (signedOrder.expirationUnixTimestampSec.lessThan(currentUnixTimestampSec)) {
             throw new Error(ExchangeContractErrs.ORDER_FILL_EXPIRED);
         }
-        const zrxTokenAddress = await this._getZRXTokenAddressAsync();
+        const zrxTokenAddress = await this._getZRXTokenAddressAsync(signedOrder.exchangeContractAddress);
         await this._validateFillOrderBalancesAndAllowancesAndThrowIfInvalidAsync(signedOrder, fillTakerAmount,
                                                                senderAddress, zrxTokenAddress);
 
         const wouldRoundingErrorOccur = await this._isRoundingErrorAsync(
             signedOrder.takerTokenAmount, fillTakerAmount, signedOrder.makerTokenAmount,
+            signedOrder.exchangeContractAddress,
         );
         if (wouldRoundingErrorOccur) {
             throw new Error(ExchangeContractErrs.ORDER_FILL_ROUNDING_ERROR);
@@ -649,7 +694,7 @@ export class ExchangeWrapper extends ContractWrapper {
             throw new Error(ExchangeContractErrs.ORDER_CANCEL_AMOUNT_ZERO);
         }
         const orderHash = await this._getOrderHashHexAsync(order);
-        const unavailableAmount = await this.getUnavailableTakerAmountAsync(orderHash);
+        const unavailableAmount = await this.getUnavailableTakerAmountAsync(orderHash, order.exchangeContractAddress);
         if (order.takerTokenAmount.minus(unavailableAmount).eq(0)) {
             throw new Error(ExchangeContractErrs.ORDER_ALREADY_CANCELLED_OR_FILLED);
         }
@@ -659,11 +704,11 @@ export class ExchangeWrapper extends ContractWrapper {
         }
     }
     private async _validateFillOrKillOrderAndThrowIfInvalidAsync(signedOrder: SignedOrder,
-                                                                 exchangeAddress: string,
+                                                                 exchangeContractAddress: string,
                                                                  fillTakerAmount: BigNumber.BigNumber) {
         // Check that fillValue available >= fillTakerAmount
-        const orderHashHex = utils.getOrderHashHex(signedOrder, exchangeAddress);
-        const unavailableTakerAmount = await this.getUnavailableTakerAmountAsync(orderHashHex);
+        const orderHashHex = utils.getOrderHashHex(signedOrder, exchangeContractAddress);
+        const unavailableTakerAmount = await this.getUnavailableTakerAmountAsync(orderHashHex, exchangeContractAddress);
         const remainingTakerAmount = signedOrder.takerTokenAmount.minus(unavailableTakerAmount);
         if (remainingTakerAmount < fillTakerAmount) {
             throw new Error(ExchangeContractErrs.INSUFFICIENT_REMAINING_FILL_AMOUNT);
@@ -740,24 +785,38 @@ export class ExchangeWrapper extends ContractWrapper {
     }
     private async _isRoundingErrorAsync(takerTokenAmount: BigNumber.BigNumber,
                                         fillTakerAmount: BigNumber.BigNumber,
-                                        makerTokenAmount: BigNumber.BigNumber): Promise<boolean> {
+                                        makerTokenAmount: BigNumber.BigNumber,
+                                        exchangeContractAddress: string): Promise<boolean> {
         await assert.isUserAddressAvailableAsync(this._web3Wrapper);
-        const exchangeInstance = await this._getExchangeContractAsync();
+        const exchangeInstance = await this._getExchangeContractAsync(exchangeContractAddress);
         const isRoundingError = await exchangeInstance.isRoundingError.call(
             takerTokenAmount, fillTakerAmount, makerTokenAmount,
         );
         return isRoundingError;
     }
-    private async _getExchangeContractAsync(): Promise<ExchangeContract> {
-        if (!_.isUndefined(this._exchangeContractIfExists)) {
-            return this._exchangeContractIfExists;
+    private async _getExchangeContractAsync(exchangeContractAddress: string): Promise<ExchangeContract> {
+        if (!_.isUndefined(this._exchangeContractByAddress[exchangeContractAddress])) {
+            return this._exchangeContractByAddress[exchangeContractAddress];
         }
+        const ExchangeArtifacts = this._getExchangeArtifactsByAddressOrThrow(exchangeContractAddress);
         const contractInstance = await this._instantiateContractIfExistsAsync((ExchangeArtifacts as any));
-        this._exchangeContractIfExists = contractInstance as ExchangeContract;
-        return this._exchangeContractIfExists;
+        this._exchangeContractByAddress[exchangeContractAddress] = contractInstance as ExchangeContract;
+        return this._exchangeContractByAddress[exchangeContractAddress];
+    }
+    private _getExchangeArtifactsByAddressOrThrow(exchangeContractAddress: string): ContractArtifact {
+        for (const exchangeArtifact of _.values<ContractArtifact>(ExchangeArtifactsByName)) {
+            const exchangeAddressesInAftifact = _.map(
+                _.values(exchangeArtifact.networks),
+                artifactsByNetwork => artifactsByNetwork.address,
+            );
+            if (_.includes(exchangeAddressesInAftifact, exchangeContractAddress)) {
+                return exchangeArtifact;
+            }
+        }
+        throw new Error(ZeroExError.CONTRACT_DOES_NOT_EXIST);
     }
-    private async _getZRXTokenAddressAsync(): Promise<string> {
-        const exchangeInstance = await this._getExchangeContractAsync();
+    private async _getZRXTokenAddressAsync(exchangeContractAddress: string): Promise<string> {
+        const exchangeInstance = await this._getExchangeContractAsync(exchangeContractAddress);
         return exchangeInstance.ZRX.call();
     }
 }
diff --git a/src/exchange_artifacts_by_name.ts b/src/exchange_artifacts_by_name.ts
new file mode 100644
index 000000000..4ecd28d43
--- /dev/null
+++ b/src/exchange_artifacts_by_name.ts
@@ -0,0 +1,6 @@
+import {ContractArtifact} from './types';
+import * as Exchange_v1 from './artifacts/exchange/Exchange.json';
+
+export const ExchangeArtifactsByName = {
+    Exchange_v1: Exchange_v1 as any as ContractArtifact,
+};
diff --git a/src/types.ts b/src/types.ts
index 200e65d56..f12d6f6c6 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -240,6 +240,7 @@ export interface Order {
     makerTokenAddress: string;
     takerTokenAddress: string;
     salt: BigNumber.BigNumber;
+    exchangeContractAddress: string;
     feeRecipient: string;
     expirationUnixTimestampSec: BigNumber.BigNumber;
 }
@@ -325,3 +326,15 @@ export interface ContractEventEmitter {
  * It is however a `Web3` library type, not a native `0x.js` type.
  */
 export type Web3Provider = Web3.Provider;
+
+export interface ExchangeContractByAddress {
+    [address: string]: ExchangeContract;
+}
+
+export interface ContractArtifact {
+    networks: {
+        [networkId: number]: {
+            address: string;
+        };
+    };
+}