Merge pull request #488 from avonian/development

Monitor different state layers with OrderWatcher

6 files changed, 80 insertions, 62 deletions

diff --git a/packages/0x.js/CHANGELOG.md b/packages/0x.js/CHANGELOG.md
index ca6b985d3..af63118a7 100644
--- a/packages/0x.js/CHANGELOG.md
+++ b/packages/0x.js/CHANGELOG.md
@@ -3,6 +3,9 @@
 ## v0.34.0 - _TBD_
 
     * Fix the bug causing `zeroEx.exchange.fillOrdersUpToAsync` validation to fail if there were some extra orders passed (#470)
+    * Remove automatic instantiation of `zeroEx.orderStateWatcher` (#488)
+    * Add `zeroEx.createOrderStateWatcher` to allow creating arbitrary number of OrderStateWatchers (#488)
+    * Added `stateLayer` setting to `OrderStateWatcherConfig` so OrderStateWatcher can be set to monitor different blockchain state layers (#488)
 
 ## v0.33.2 - _March 18, 2018_
 
diff --git a/packages/0x.js/src/0x.ts b/packages/0x.js/src/0x.ts
index 0dd728ff1..7627f1d6e 100644
--- a/packages/0x.js/src/0x.ts
+++ b/packages/0x.js/src/0x.ts
@@ -15,7 +15,7 @@ import { OrderStateWatcher } from './order_watcher/order_state_watcher';
 import { zeroExConfigSchema } from './schemas/zero_ex_config_schema';
 import { zeroExPrivateNetworkConfigSchema } from './schemas/zero_ex_private_network_config_schema';
 import { zeroExPublicNetworkConfigSchema } from './schemas/zero_ex_public_network_config_schema';
-import { Web3Provider, ZeroExConfig, ZeroExError } from './types';
+import { OrderStateWatcherConfig, ZeroExConfig, ZeroExError } from './types';
 import { assert } from './utils/assert';
 import { constants } from './utils/constants';
 import { decorators } from './utils/decorators';
@@ -57,11 +57,6 @@ export class ZeroEx {
      * tokenTransferProxy smart contract.
      */
     public proxy: TokenTransferProxyWrapper;
-    /**
-     * An instance of the OrderStateWatcher class containing methods for watching a set of orders for relevant
-     * blockchain state changes.
-     */
-    public orderStateWatcher: OrderStateWatcher;
     private _web3Wrapper: Web3Wrapper;
     private _abiDecoder: AbiDecoder;
     /**
@@ -197,13 +192,6 @@ export class ZeroEx {
             config.tokenRegistryContractAddress,
         );
         this.etherToken = new EtherTokenWrapper(this._web3Wrapper, config.networkId, this._abiDecoder, this.token);
-        this.orderStateWatcher = new OrderStateWatcher(
-            this._web3Wrapper,
-            this._abiDecoder,
-            this.token,
-            this.exchange,
-            config.orderWatcherConfig,
-        );
     }
     /**
      * Sets a new web3 provider for 0x.js. Updating the provider will stop all
@@ -336,6 +324,21 @@ export class ZeroEx {
         const txReceipt = await txReceiptPromise;
         return txReceipt;
     }
+    /**
+     * Instantiates and returns a new OrderStateWatcher instance.
+     * Defaults to watching the pending state.
+     * @param   config      The configuration object. Look up the type for the description.
+     * @return  An instance of the 0x.js OrderStateWatcher class.
+     */
+    public createOrderStateWatcher(config?: OrderStateWatcherConfig) {
+        return new OrderStateWatcher(
+            this._web3Wrapper,
+            this._abiDecoder,
+            this.token,
+            this.exchange,
+            config,
+        );
+    }
     /*
      * HACK: `TokenWrapper` needs a token transfer proxy address. `TokenTransferProxy` address is fetched from
      * an `ExchangeWrapper`. `ExchangeWrapper` needs `TokenWrapper` to validate orders, creating a dependency cycle.
diff --git a/packages/0x.js/src/order_watcher/event_watcher.ts b/packages/0x.js/src/order_watcher/event_watcher.ts
index 246ab8292..d01542a8c 100644
--- a/packages/0x.js/src/order_watcher/event_watcher.ts
+++ b/packages/0x.js/src/order_watcher/event_watcher.ts
@@ -22,8 +22,10 @@ export class EventWatcher {
     private _pollingIntervalMs: number;
     private _intervalIdIfExists?: NodeJS.Timer;
     private _lastEvents: LogEntry[] = [];
-    constructor(web3Wrapper: Web3Wrapper, pollingIntervalIfExistsMs: undefined | number) {
+    private _stateLayer: BlockParamLiteral;
+    constructor(web3Wrapper: Web3Wrapper, pollingIntervalIfExistsMs: undefined | number, stateLayer: BlockParamLiteral = BlockParamLiteral.Latest) {
         this._web3Wrapper = web3Wrapper;
+        this._stateLayer = stateLayer;
         this._pollingIntervalMs = _.isUndefined(pollingIntervalIfExistsMs)
             ? DEFAULT_EVENT_POLLING_INTERVAL_MS
             : pollingIntervalIfExistsMs;
@@ -69,8 +71,8 @@ export class EventWatcher {
     }
     private async _getEventsAsync(): Promise<LogEntry[]> {
         const eventFilter = {
-            fromBlock: BlockParamLiteral.Pending,
-            toBlock: BlockParamLiteral.Pending,
+            fromBlock: this._stateLayer,
+            toBlock: this._stateLayer,
         };
         const events = await this._web3Wrapper.getLogsAsync(eventFilter);
         return events;
diff --git a/packages/0x.js/src/order_watcher/order_state_watcher.ts b/packages/0x.js/src/order_watcher/order_state_watcher.ts
index 9cccadb7f..bfd250e21 100644
--- a/packages/0x.js/src/order_watcher/order_state_watcher.ts
+++ b/packages/0x.js/src/order_watcher/order_state_watcher.ts
@@ -86,10 +86,13 @@ export class OrderStateWatcher {
         this._abiDecoder = abiDecoder;
         this._web3Wrapper = web3Wrapper;
         const pollingIntervalIfExistsMs = _.isUndefined(config) ? undefined : config.eventPollingIntervalMs;
-        this._eventWatcher = new EventWatcher(web3Wrapper, pollingIntervalIfExistsMs);
+        const stateLayer = _.isUndefined(config) || _.isUndefined(config.stateLayer)
+            ? BlockParamLiteral.Latest
+            : config.stateLayer;
+        this._eventWatcher = new EventWatcher(web3Wrapper, pollingIntervalIfExistsMs, stateLayer);
         this._balanceAndProxyAllowanceLazyStore = new BalanceAndProxyAllowanceLazyStore(
             token,
-            BlockParamLiteral.Pending,
+            stateLayer,
         );
         this._orderFilledCancelledLazyStore = new OrderFilledCancelledLazyStore(exchange);
         this._orderStateUtils = new OrderStateUtils(
diff --git a/packages/0x.js/src/types.ts b/packages/0x.js/src/types.ts
index 38cfb6306..7f1f140ca 100644
--- a/packages/0x.js/src/types.ts
+++ b/packages/0x.js/src/types.ts
@@ -165,16 +165,18 @@ export type Web3Provider = Web3.Provider;
 
 /*
  * orderExpirationCheckingIntervalMs: How often to check for expired orders. Default: 50
- * eventPollingIntervalMs: How often to poll the Ethereum node for new events. Defaults: 200
+ * eventPollingIntervalMs: How often to poll the Ethereum node for new events. Default: 200
  * expirationMarginMs: Amount of time before order expiry that you'd like to be notified
- * of an orders expiration. Defaults: 0
+ * of an orders expiration. Default: 0
  * cleanupJobIntervalMs: How often to run a cleanup job which revalidates all the orders. Defaults: 1h
+ * stateLayer: Optional blockchain state layer OrderWatcher will monitor for new events. Default: latest
  */
 export interface OrderStateWatcherConfig {
     orderExpirationCheckingIntervalMs?: number;
     eventPollingIntervalMs?: number;
     expirationMarginMs?: number;
     cleanupJobIntervalMs?: number;
+    stateLayer: BlockParamLiteral;
 }
 
 /*
diff --git a/packages/0x.js/test/order_state_watcher_test.ts b/packages/0x.js/test/order_state_watcher_test.ts
index d08272c3b..4f727d495 100644
--- a/packages/0x.js/test/order_state_watcher_test.ts
+++ b/packages/0x.js/test/order_state_watcher_test.ts
@@ -15,6 +15,9 @@ import {
     ZeroEx,
     ZeroExError,
 } from '../src';
+import {
+    OrderStateWatcher,
+} from '../src/order_watcher/order_state_watcher';
 import { DoneCallback } from '../src/types';
 
 import { chaiSetup } from './utils/chai_setup';
@@ -43,6 +46,7 @@ describe('OrderStateWatcher', () => {
     let maker: string;
     let taker: string;
     let signedOrder: SignedOrder;
+    let orderStateWatcher: OrderStateWatcher;
     const config = {
         networkId: constants.TESTRPC_NETWORK_ID,
     };
@@ -50,6 +54,7 @@ describe('OrderStateWatcher', () => {
     const fillableAmount = ZeroEx.toBaseUnitAmount(new BigNumber(5), decimals);
     before(async () => {
         zeroEx = new ZeroEx(web3.currentProvider, config);
+        orderStateWatcher = zeroEx.createOrderStateWatcher();
         exchangeContractAddress = zeroEx.exchange.getContractAddress();
         userAddresses = await zeroEx.getAvailableAddressesAsync();
         [, maker, taker] = userAddresses;
@@ -76,17 +81,17 @@ describe('OrderStateWatcher', () => {
                 fillableAmount,
             );
             const orderHash = ZeroEx.getOrderHashHex(signedOrder);
-            zeroEx.orderStateWatcher.addOrder(signedOrder);
-            expect((zeroEx.orderStateWatcher as any)._orderByOrderHash).to.include({
+            orderStateWatcher.addOrder(signedOrder);
+            expect((orderStateWatcher as any)._orderByOrderHash).to.include({
                 [orderHash]: signedOrder,
             });
-            let dependentOrderHashes = (zeroEx.orderStateWatcher as any)._dependentOrderHashes;
+            let dependentOrderHashes = (orderStateWatcher as any)._dependentOrderHashes;
             expect(dependentOrderHashes[signedOrder.maker][signedOrder.makerTokenAddress]).to.have.keys(orderHash);
-            zeroEx.orderStateWatcher.removeOrder(orderHash);
-            expect((zeroEx.orderStateWatcher as any)._orderByOrderHash).to.not.include({
+            orderStateWatcher.removeOrder(orderHash);
+            expect((orderStateWatcher as any)._orderByOrderHash).to.not.include({
                 [orderHash]: signedOrder,
             });
-            dependentOrderHashes = (zeroEx.orderStateWatcher as any)._dependentOrderHashes;
+            dependentOrderHashes = (orderStateWatcher as any)._dependentOrderHashes;
             expect(dependentOrderHashes[signedOrder.maker]).to.be.undefined();
         });
         it('should no-op when removing a non-existing order', async () => {
@@ -103,23 +108,23 @@ describe('OrderStateWatcher', () => {
                 .split('')
                 .reverse()
                 .join('')}`;
-            zeroEx.orderStateWatcher.removeOrder(nonExistentOrderHash);
+            orderStateWatcher.removeOrder(nonExistentOrderHash);
         });
     });
     describe('#subscribe', async () => {
         afterEach(async () => {
-            zeroEx.orderStateWatcher.unsubscribe();
+            orderStateWatcher.unsubscribe();
         });
         it('should fail when trying to subscribe twice', async () => {
-            zeroEx.orderStateWatcher.subscribe(_.noop);
-            expect(() => zeroEx.orderStateWatcher.subscribe(_.noop)).to.throw(ZeroExError.SubscriptionAlreadyPresent);
+            orderStateWatcher.subscribe(_.noop);
+            expect(() => orderStateWatcher.subscribe(_.noop)).to.throw(ZeroExError.SubscriptionAlreadyPresent);
         });
     });
     describe('tests with cleanup', async () => {
         afterEach(async () => {
-            zeroEx.orderStateWatcher.unsubscribe();
+            orderStateWatcher.unsubscribe();
             const orderHash = ZeroEx.getOrderHashHex(signedOrder);
-            zeroEx.orderStateWatcher.removeOrder(orderHash);
+            orderStateWatcher.removeOrder(orderHash);
         });
         it('should emit orderStateInvalid when maker allowance set to 0 for watched order', (done: DoneCallback) => {
             (async () => {
@@ -131,14 +136,14 @@ describe('OrderStateWatcher', () => {
                     fillableAmount,
                 );
                 const orderHash = ZeroEx.getOrderHashHex(signedOrder);
-                zeroEx.orderStateWatcher.addOrder(signedOrder);
+                orderStateWatcher.addOrder(signedOrder);
                 const callback = reportNodeCallbackErrors(done)((orderState: OrderState) => {
                     expect(orderState.isValid).to.be.false();
                     const invalidOrderState = orderState as OrderStateInvalid;
                     expect(invalidOrderState.orderHash).to.be.equal(orderHash);
                     expect(invalidOrderState.error).to.be.equal(ExchangeContractErrs.InsufficientMakerAllowance);
                 });
-                zeroEx.orderStateWatcher.subscribe(callback);
+                orderStateWatcher.subscribe(callback);
                 await zeroEx.token.setProxyAllowanceAsync(makerToken.address, maker, new BigNumber(0));
             })().catch(done);
         });
@@ -151,11 +156,11 @@ describe('OrderStateWatcher', () => {
                     taker,
                     fillableAmount,
                 );
-                zeroEx.orderStateWatcher.addOrder(signedOrder);
+                orderStateWatcher.addOrder(signedOrder);
                 const callback = reportNodeCallbackErrors(done)((orderState: OrderState) => {
                     throw new Error('OrderState callback fired for irrelevant order');
                 });
-                zeroEx.orderStateWatcher.subscribe(callback);
+                orderStateWatcher.subscribe(callback);
                 const notTheMaker = userAddresses[0];
                 const anyRecipient = taker;
                 const transferAmount = new BigNumber(2);
@@ -175,14 +180,14 @@ describe('OrderStateWatcher', () => {
                     fillableAmount,
                 );
                 const orderHash = ZeroEx.getOrderHashHex(signedOrder);
-                zeroEx.orderStateWatcher.addOrder(signedOrder);
+                orderStateWatcher.addOrder(signedOrder);
                 const callback = reportNodeCallbackErrors(done)((orderState: OrderState) => {
                     expect(orderState.isValid).to.be.false();
                     const invalidOrderState = orderState as OrderStateInvalid;
                     expect(invalidOrderState.orderHash).to.be.equal(orderHash);
                     expect(invalidOrderState.error).to.be.equal(ExchangeContractErrs.InsufficientMakerBalance);
                 });
-                zeroEx.orderStateWatcher.subscribe(callback);
+                orderStateWatcher.subscribe(callback);
                 const anyRecipient = taker;
                 const makerBalance = await zeroEx.token.getBalanceAsync(makerToken.address, maker);
                 await zeroEx.token.transferAsync(makerToken.address, maker, anyRecipient, makerBalance);
@@ -198,7 +203,7 @@ describe('OrderStateWatcher', () => {
                     fillableAmount,
                 );
                 const orderHash = ZeroEx.getOrderHashHex(signedOrder);
-                zeroEx.orderStateWatcher.addOrder(signedOrder);
+                orderStateWatcher.addOrder(signedOrder);
 
                 const callback = reportNodeCallbackErrors(done)((orderState: OrderState) => {
                     expect(orderState.isValid).to.be.false();
@@ -206,7 +211,7 @@ describe('OrderStateWatcher', () => {
                     expect(invalidOrderState.orderHash).to.be.equal(orderHash);
                     expect(invalidOrderState.error).to.be.equal(ExchangeContractErrs.OrderRemainingFillAmountZero);
                 });
-                zeroEx.orderStateWatcher.subscribe(callback);
+                orderStateWatcher.subscribe(callback);
 
                 const shouldThrowOnInsufficientBalanceOrAllowance = true;
                 await zeroEx.exchange.fillOrderAsync(
@@ -230,7 +235,7 @@ describe('OrderStateWatcher', () => {
                 const makerBalance = await zeroEx.token.getBalanceAsync(makerToken.address, maker);
                 const fillAmountInBaseUnits = new BigNumber(2);
                 const orderHash = ZeroEx.getOrderHashHex(signedOrder);
-                zeroEx.orderStateWatcher.addOrder(signedOrder);
+                orderStateWatcher.addOrder(signedOrder);
 
                 const callback = reportNodeCallbackErrors(done)((orderState: OrderState) => {
                     expect(orderState.isValid).to.be.true();
@@ -247,7 +252,7 @@ describe('OrderStateWatcher', () => {
                     );
                     expect(orderRelevantState.makerBalance).to.be.bignumber.equal(remainingMakerBalance);
                 });
-                zeroEx.orderStateWatcher.subscribe(callback);
+                orderStateWatcher.subscribe(callback);
                 const shouldThrowOnInsufficientBalanceOrAllowance = true;
                 await zeroEx.exchange.fillOrderAsync(
                     signedOrder,
@@ -272,8 +277,8 @@ describe('OrderStateWatcher', () => {
                     taker,
                 );
                 const callback = reportNodeCallbackErrors(done)();
-                zeroEx.orderStateWatcher.addOrder(signedOrder);
-                zeroEx.orderStateWatcher.subscribe(callback);
+                orderStateWatcher.addOrder(signedOrder);
+                orderStateWatcher.subscribe(callback);
                 await zeroEx.token.setProxyAllowanceAsync(zrxTokenAddress, maker, new BigNumber(0));
             })().catch(done);
         });
@@ -292,7 +297,7 @@ describe('OrderStateWatcher', () => {
                     );
                     const fillAmountInBaseUnits = ZeroEx.toBaseUnitAmount(new BigNumber(2), decimals);
                     const orderHash = ZeroEx.getOrderHashHex(signedOrder);
-                    zeroEx.orderStateWatcher.addOrder(signedOrder);
+                    orderStateWatcher.addOrder(signedOrder);
                     const callback = reportNodeCallbackErrors(done)((orderState: OrderState) => {
                         expect(orderState.isValid).to.be.true();
                         const validOrderState = orderState as OrderStateValid;
@@ -305,7 +310,7 @@ describe('OrderStateWatcher', () => {
                             ZeroEx.toBaseUnitAmount(new BigNumber(8), decimals),
                         );
                     });
-                    zeroEx.orderStateWatcher.subscribe(callback);
+                    orderStateWatcher.subscribe(callback);
                     const shouldThrowOnInsufficientBalanceOrAllowance = true;
                     await zeroEx.exchange.fillOrderAsync(
                         signedOrder,
@@ -326,7 +331,7 @@ describe('OrderStateWatcher', () => {
                     );
 
                     const changedMakerApprovalAmount = ZeroEx.toBaseUnitAmount(new BigNumber(3), decimals);
-                    zeroEx.orderStateWatcher.addOrder(signedOrder);
+                    orderStateWatcher.addOrder(signedOrder);
 
                     const callback = reportNodeCallbackErrors(done)((orderState: OrderState) => {
                         const validOrderState = orderState as OrderStateValid;
@@ -338,7 +343,7 @@ describe('OrderStateWatcher', () => {
                             changedMakerApprovalAmount,
                         );
                     });
-                    zeroEx.orderStateWatcher.subscribe(callback);
+                    orderStateWatcher.subscribe(callback);
                     await zeroEx.token.setProxyAllowanceAsync(makerToken.address, maker, changedMakerApprovalAmount);
                 })().catch(done);
             });
@@ -356,7 +361,7 @@ describe('OrderStateWatcher', () => {
 
                     const remainingAmount = ZeroEx.toBaseUnitAmount(new BigNumber(1), decimals);
                     const transferAmount = makerBalance.sub(remainingAmount);
-                    zeroEx.orderStateWatcher.addOrder(signedOrder);
+                    orderStateWatcher.addOrder(signedOrder);
 
                     const callback = reportNodeCallbackErrors(done)((orderState: OrderState) => {
                         expect(orderState.isValid).to.be.true();
@@ -369,7 +374,7 @@ describe('OrderStateWatcher', () => {
                             remainingAmount,
                         );
                     });
-                    zeroEx.orderStateWatcher.subscribe(callback);
+                    orderStateWatcher.subscribe(callback);
                     await zeroEx.token.transferAsync(makerToken.address, maker, ZeroEx.NULL_ADDRESS, transferAmount);
                 })().catch(done);
             });
@@ -391,7 +396,7 @@ describe('OrderStateWatcher', () => {
 
                     const remainingTokenAmount = ZeroEx.toBaseUnitAmount(new BigNumber(4), decimals);
                     const transferTokenAmount = makerFee.sub(remainingTokenAmount);
-                    zeroEx.orderStateWatcher.addOrder(signedOrder);
+                    orderStateWatcher.addOrder(signedOrder);
 
                     const callback = reportNodeCallbackErrors(done)((orderState: OrderState) => {
                         expect(orderState.isValid).to.be.true();
@@ -401,7 +406,7 @@ describe('OrderStateWatcher', () => {
                             remainingTokenAmount,
                         );
                     });
-                    zeroEx.orderStateWatcher.subscribe(callback);
+                    orderStateWatcher.subscribe(callback);
                     await zeroEx.exchange.cancelOrderAsync(signedOrder, transferTokenAmount);
                 })().catch(done);
             });
@@ -425,7 +430,7 @@ describe('OrderStateWatcher', () => {
 
                     const remainingTokenAmount = ZeroEx.toBaseUnitAmount(new BigNumber(4), decimals);
                     const transferTokenAmount = makerFee.sub(remainingTokenAmount);
-                    zeroEx.orderStateWatcher.addOrder(signedOrder);
+                    orderStateWatcher.addOrder(signedOrder);
 
                     const callback = reportNodeCallbackErrors(done)((orderState: OrderState) => {
                         const validOrderState = orderState as OrderStateValid;
@@ -434,7 +439,7 @@ describe('OrderStateWatcher', () => {
                             remainingFeeAmount,
                         );
                     });
-                    zeroEx.orderStateWatcher.subscribe(callback);
+                    orderStateWatcher.subscribe(callback);
                     await zeroEx.token.setProxyAllowanceAsync(zrxTokenAddress, maker, remainingFeeAmount);
                     await zeroEx.token.transferAsync(
                         makerToken.address,
@@ -460,7 +465,7 @@ describe('OrderStateWatcher', () => {
                         feeRecipient,
                     );
 
-                    zeroEx.orderStateWatcher.addOrder(signedOrder);
+                    orderStateWatcher.addOrder(signedOrder);
 
                     const callback = reportNodeCallbackErrors(done)((orderState: OrderState) => {
                         const validOrderState = orderState as OrderStateValid;
@@ -469,7 +474,7 @@ describe('OrderStateWatcher', () => {
                             fillableAmount,
                         );
                     });
-                    zeroEx.orderStateWatcher.subscribe(callback);
+                    orderStateWatcher.subscribe(callback);
                     await zeroEx.token.setProxyAllowanceAsync(
                         makerToken.address,
                         maker,
@@ -488,7 +493,7 @@ describe('OrderStateWatcher', () => {
                     fillableAmount,
                 );
                 const orderHash = ZeroEx.getOrderHashHex(signedOrder);
-                zeroEx.orderStateWatcher.addOrder(signedOrder);
+                orderStateWatcher.addOrder(signedOrder);
 
                 const callback = reportNodeCallbackErrors(done)((orderState: OrderState) => {
                     expect(orderState.isValid).to.be.false();
@@ -496,7 +501,7 @@ describe('OrderStateWatcher', () => {
                     expect(invalidOrderState.orderHash).to.be.equal(orderHash);
                     expect(invalidOrderState.error).to.be.equal(ExchangeContractErrs.OrderRemainingFillAmountZero);
                 });
-                zeroEx.orderStateWatcher.subscribe(callback);
+                orderStateWatcher.subscribe(callback);
 
                 await zeroEx.exchange.cancelOrderAsync(signedOrder, fillableAmount);
             })().catch(done);
@@ -512,7 +517,7 @@ describe('OrderStateWatcher', () => {
                     fillableAmount,
                 );
                 const orderHash = ZeroEx.getOrderHashHex(signedOrder);
-                zeroEx.orderStateWatcher.addOrder(signedOrder);
+                orderStateWatcher.addOrder(signedOrder);
 
                 const callback = reportNodeCallbackErrors(done)((orderState: OrderState) => {
                     expect(orderState.isValid).to.be.false();
@@ -520,7 +525,7 @@ describe('OrderStateWatcher', () => {
                     expect(invalidOrderState.orderHash).to.be.equal(orderHash);
                     expect(invalidOrderState.error).to.be.equal(ExchangeContractErrs.OrderFillRoundingError);
                 });
-                zeroEx.orderStateWatcher.subscribe(callback);
+                orderStateWatcher.subscribe(callback);
                 await zeroEx.exchange.cancelOrderAsync(
                     signedOrder,
                     fillableAmount.minus(remainingFillableAmountInBaseUnits),
@@ -539,7 +544,7 @@ describe('OrderStateWatcher', () => {
 
                 const cancelAmountInBaseUnits = new BigNumber(2);
                 const orderHash = ZeroEx.getOrderHashHex(signedOrder);
-                zeroEx.orderStateWatcher.addOrder(signedOrder);
+                orderStateWatcher.addOrder(signedOrder);
 
                 const callback = reportNodeCallbackErrors(done)((orderState: OrderState) => {
                     expect(orderState.isValid).to.be.true();
@@ -548,7 +553,7 @@ describe('OrderStateWatcher', () => {
                     const orderRelevantState = validOrderState.orderRelevantState;
                     expect(orderRelevantState.cancelledTakerTokenAmount).to.be.bignumber.equal(cancelAmountInBaseUnits);
                 });
-                zeroEx.orderStateWatcher.subscribe(callback);
+                orderStateWatcher.subscribe(callback);
                 await zeroEx.exchange.cancelOrderAsync(signedOrder, cancelAmountInBaseUnits);
             })().catch(done);
         });