Merge pull request #1105 from 0xProject/feature/contracts-artifacts-re-org

Reorganize and modularize generated contract wrappers and artifacts

9 files changed, 137 insertions, 319 deletions

diff --git a/packages/contract-wrappers/src/contract_wrappers/contract_wrapper.ts b/packages/contract-wrappers/src/contract_wrappers/contract_wrapper.ts
index f7a89e3be..e03e4188b 100644
--- a/packages/contract-wrappers/src/contract_wrappers/contract_wrapper.ts
+++ b/packages/contract-wrappers/src/contract_wrappers/contract_wrapper.ts
@@ -3,7 +3,6 @@ import { marshaller, Web3Wrapper } from '@0xproject/web3-wrapper';
 import {
     BlockParamLiteral,
     ContractAbi,
-    ContractArtifact,
     FilterObject,
     LogEntry,
     LogWithDecodedArgs,
@@ -24,22 +23,10 @@ import {
 import { constants } from '../utils/constants';
 import { filterUtils } from '../utils/filter_utils';
 
-const CONTRACT_NAME_TO_NOT_FOUND_ERROR: {
-    [contractName: string]: ContractWrappersError;
-} = {
-    ZRX: ContractWrappersError.ZRXContractDoesNotExist,
-    EtherToken: ContractWrappersError.EtherTokenContractDoesNotExist,
-    ERC20Token: ContractWrappersError.ERC20TokenContractDoesNotExist,
-    ERC20Proxy: ContractWrappersError.ERC20ProxyContractDoesNotExist,
-    ERC721Token: ContractWrappersError.ERC721TokenContractDoesNotExist,
-    ERC721Proxy: ContractWrappersError.ERC721ProxyContractDoesNotExist,
-    Exchange: ContractWrappersError.ExchangeContractDoesNotExist,
-};
-
 export abstract class ContractWrapper {
     public abstract abi: ContractAbi;
-    protected _web3Wrapper: Web3Wrapper;
     protected _networkId: number;
+    protected _web3Wrapper: Web3Wrapper;
     private _blockAndLogStreamerIfExists: BlockAndLogStreamer<Block, Log> | undefined;
     private _blockPollingIntervalMs: number;
     private _blockAndLogStreamIntervalIfExists?: NodeJS.Timer;
@@ -124,40 +111,6 @@ export abstract class ContractWrapper {
         const logWithDecodedArgs = abiDecoder.tryToDecodeLogOrNoop(log);
         return logWithDecodedArgs;
     }
-    protected async _getContractAbiAndAddressFromArtifactsAsync(
-        artifact: ContractArtifact,
-        addressIfExists?: string,
-    ): Promise<[ContractAbi, string]> {
-        let contractAddress: string;
-        if (_.isUndefined(addressIfExists)) {
-            if (_.isUndefined(artifact.networks[this._networkId])) {
-                throw new Error(ContractWrappersError.ContractNotDeployedOnNetwork);
-            }
-            contractAddress = artifact.networks[this._networkId].address.toLowerCase();
-        } else {
-            contractAddress = addressIfExists;
-        }
-        const doesContractExist = await this._web3Wrapper.doesContractExistAtAddressAsync(contractAddress);
-        if (!doesContractExist) {
-            throw new Error(CONTRACT_NAME_TO_NOT_FOUND_ERROR[artifact.contractName]);
-        }
-        const abiAndAddress: [ContractAbi, string] = [artifact.compilerOutput.abi, contractAddress];
-        return abiAndAddress;
-    }
-    protected _getContractAddress(artifact: ContractArtifact, addressIfExists?: string): string {
-        if (_.isUndefined(addressIfExists)) {
-            if (_.isUndefined(artifact.networks[this._networkId])) {
-                throw new Error(ContractWrappersError.ContractNotDeployedOnNetwork);
-            }
-            const contractAddress = artifact.networks[this._networkId].address;
-            if (_.isUndefined(contractAddress)) {
-                throw new Error(CONTRACT_NAME_TO_NOT_FOUND_ERROR[artifact.contractName]);
-            }
-            return contractAddress;
-        } else {
-            return addressIfExists;
-        }
-    }
     private _onLogStateChanged<ArgsType extends ContractEventArgs>(isRemoved: boolean, rawLog: RawLogEntry): void {
         const log: LogEntry = marshaller.unmarshalLog(rawLog);
         _.forEach(this._filters, (filter: FilterObject, filterToken: string) => {
@@ -222,14 +175,6 @@ export abstract class ContractWrapper {
         });
         return logs as RawLogEntry[];
     }
-    // HACK: This should be a package-scoped method (which doesn't exist in TS)
-    // We don't want this method available in the public interface for all classes
-    // who inherit from ContractWrapper, and it is only used by the internal implementation
-    // of those higher classes.
-    // tslint:disable-next-line:no-unused-variable
-    private _setNetworkId(networkId: number): void {
-        this._networkId = networkId;
-    }
     private _stopBlockAndLogStream(): void {
         if (_.isUndefined(this._blockAndLogStreamerIfExists)) {
             throw new Error(ContractWrappersError.SubscriptionNotFound);
diff --git a/packages/contract-wrappers/src/contract_wrappers/erc20_proxy_wrapper.ts b/packages/contract-wrappers/src/contract_wrappers/erc20_proxy_wrapper.ts
index ff027d78a..e59b2c20b 100644
--- a/packages/contract-wrappers/src/contract_wrappers/erc20_proxy_wrapper.ts
+++ b/packages/contract-wrappers/src/contract_wrappers/erc20_proxy_wrapper.ts
@@ -1,38 +1,39 @@
+import { ERC20ProxyContract } from '@0xproject/abi-gen-wrappers';
+import { ERC20Proxy } from '@0xproject/contract-artifacts';
 import { AssetProxyId } from '@0xproject/types';
 import { Web3Wrapper } from '@0xproject/web3-wrapper';
 import { ContractAbi } from 'ethereum-types';
 import * as _ from 'lodash';
 
-import { artifacts } from '../artifacts';
 import { assert } from '../utils/assert';
+import { _getDefaultContractAddresses } from '../utils/contract_addresses';
 
 import { ContractWrapper } from './contract_wrapper';
-import { ERC20ProxyContract } from './generated/erc20_proxy';
 
 /**
  * This class includes the functionality related to interacting with the ERC20Proxy contract.
  */
 export class ERC20ProxyWrapper extends ContractWrapper {
-    public abi: ContractAbi = artifacts.ERC20Proxy.compilerOutput.abi;
+    public abi: ContractAbi = ERC20Proxy.compilerOutput.abi;
+    public address: string;
     private _erc20ProxyContractIfExists?: ERC20ProxyContract;
-    private _contractAddressIfExists?: string;
     /**
      * Instantiate ERC20ProxyWrapper
      * @param web3Wrapper Web3Wrapper instance to use
      * @param networkId Desired networkId
-     * @param contractAddressIfExists The contract address to use. This is usually pulled from
-     * the artifacts but needs to be specified when using with your own custom testnet.
+     * @param address The address of the ERC20Proxy contract. If undefined, will
+     * default to the known address corresponding to the networkId.
      */
-    constructor(web3Wrapper: Web3Wrapper, networkId: number, contractAddressIfExists?: string) {
+    constructor(web3Wrapper: Web3Wrapper, networkId: number, address?: string) {
         super(web3Wrapper, networkId);
-        this._contractAddressIfExists = contractAddressIfExists;
+        this.address = _.isUndefined(address) ? _getDefaultContractAddresses(networkId).erc20Proxy : address;
     }
     /**
      * Get the 4 bytes ID of this asset proxy
      * @return  Proxy id
      */
     public async getProxyIdAsync(): Promise<AssetProxyId> {
-        const ERC20ProxyContractInstance = await this._getERC20ProxyContractAsync();
+        const ERC20ProxyContractInstance = this._getERC20ProxyContract();
         const proxyId = (await ERC20ProxyContractInstance.getProxyId.callAsync()) as AssetProxyId;
         return proxyId;
     }
@@ -44,7 +45,7 @@ export class ERC20ProxyWrapper extends ContractWrapper {
     public async isAuthorizedAsync(exchangeContractAddress: string): Promise<boolean> {
         assert.isETHAddressHex('exchangeContractAddress', exchangeContractAddress);
         const normalizedExchangeContractAddress = exchangeContractAddress.toLowerCase();
-        const ERC20ProxyContractInstance = await this._getERC20ProxyContractAsync();
+        const ERC20ProxyContractInstance = this._getERC20ProxyContract();
         const isAuthorized = await ERC20ProxyContractInstance.authorized.callAsync(normalizedExchangeContractAddress);
         return isAuthorized;
     }
@@ -53,36 +54,17 @@ export class ERC20ProxyWrapper extends ContractWrapper {
      * @return  The list of authorized addresses.
      */
     public async getAuthorizedAddressesAsync(): Promise<string[]> {
-        const ERC20ProxyContractInstance = await this._getERC20ProxyContractAsync();
+        const ERC20ProxyContractInstance = this._getERC20ProxyContract();
         const authorizedAddresses = await ERC20ProxyContractInstance.getAuthorizedAddresses.callAsync();
         return authorizedAddresses;
     }
-    /**
-     * Retrieves the Ethereum address of the ERC20Proxy contract deployed on the network
-     * that the user-passed web3 provider is connected to.
-     * @returns The Ethereum address of the ERC20Proxy contract being used.
-     */
-    public getContractAddress(): string {
-        const contractAddress = this._getContractAddress(artifacts.ERC20Proxy, this._contractAddressIfExists);
-        return contractAddress;
-    }
-    // HACK: We don't want this method to be visible to the other units within that package but not to the end user.
-    // TS doesn't give that possibility and therefore we make it private and access it over an any cast. Because of that tslint sees it as unused.
-    // tslint:disable-next-line:no-unused-variable
-    private _invalidateContractInstance(): void {
-        delete this._erc20ProxyContractIfExists;
-    }
-    private async _getERC20ProxyContractAsync(): Promise<ERC20ProxyContract> {
+    private _getERC20ProxyContract(): ERC20ProxyContract {
         if (!_.isUndefined(this._erc20ProxyContractIfExists)) {
             return this._erc20ProxyContractIfExists;
         }
-        const [abi, address] = await this._getContractAbiAndAddressFromArtifactsAsync(
-            artifacts.ERC20Proxy,
-            this._contractAddressIfExists,
-        );
         const contractInstance = new ERC20ProxyContract(
-            abi,
-            address,
+            this.abi,
+            this.address,
             this._web3Wrapper.getProvider(),
             this._web3Wrapper.getContractDefaults(),
         );
diff --git a/packages/contract-wrappers/src/contract_wrappers/erc20_token_wrapper.ts b/packages/contract-wrappers/src/contract_wrappers/erc20_token_wrapper.ts
index 4625cef6a..192eaf0a7 100644
--- a/packages/contract-wrappers/src/contract_wrappers/erc20_token_wrapper.ts
+++ b/packages/contract-wrappers/src/contract_wrappers/erc20_token_wrapper.ts
@@ -1,10 +1,11 @@
+import { ERC20TokenContract, ERC20TokenEventArgs, ERC20TokenEvents } from '@0xproject/abi-gen-wrappers';
+import { ERC20Token } from '@0xproject/contract-artifacts';
 import { schemas } from '@0xproject/json-schemas';
 import { BigNumber } from '@0xproject/utils';
 import { Web3Wrapper } from '@0xproject/web3-wrapper';
 import { ContractAbi, LogWithDecodedArgs } from 'ethereum-types';
 import * as _ from 'lodash';
 
-import { artifacts } from '../artifacts';
 import { methodOptsSchema } from '../schemas/method_opts_schema';
 import { txOptsSchema } from '../schemas/tx_opts_schema';
 import {
@@ -20,7 +21,6 @@ import { constants } from '../utils/constants';
 
 import { ContractWrapper } from './contract_wrapper';
 import { ERC20ProxyWrapper } from './erc20_proxy_wrapper';
-import { ERC20TokenContract, ERC20TokenEventArgs, ERC20TokenEvents } from './generated/erc20_token';
 
 const removeUndefinedProperties = _.pickBy;
 
@@ -30,7 +30,7 @@ const removeUndefinedProperties = _.pickBy;
  * to the 0x ERC20 Proxy smart contract.
  */
 export class ERC20TokenWrapper extends ContractWrapper {
-    public abi: ContractAbi = artifacts.ERC20Token.compilerOutput.abi;
+    public abi: ContractAbi = ERC20Token.compilerOutput.abi;
     public UNLIMITED_ALLOWANCE_IN_BASE_UNITS = constants.UNLIMITED_ALLOWANCE_IN_BASE_UNITS;
     private _tokenContractsByAddress: { [address: string]: ERC20TokenContract };
     private _erc20ProxyWrapper: ERC20ProxyWrapper;
@@ -189,7 +189,7 @@ export class ERC20TokenWrapper extends ContractWrapper {
         ownerAddress: string,
         methodOpts: MethodOpts = {},
     ): Promise<BigNumber> {
-        const proxyAddress = this._erc20ProxyWrapper.getContractAddress();
+        const proxyAddress = this._erc20ProxyWrapper.address;
         const allowanceInBaseUnits = await this.getAllowanceAsync(tokenAddress, ownerAddress, proxyAddress, methodOpts);
         return allowanceInBaseUnits;
     }
@@ -209,7 +209,7 @@ export class ERC20TokenWrapper extends ContractWrapper {
         amountInBaseUnits: BigNumber,
         txOpts: TransactionOpts = {},
     ): Promise<string> {
-        const proxyAddress = this._erc20ProxyWrapper.getContractAddress();
+        const proxyAddress = this._erc20ProxyWrapper.address;
         const txHash = await this.setAllowanceAsync(
             tokenAddress,
             ownerAddress,
@@ -373,7 +373,7 @@ export class ERC20TokenWrapper extends ContractWrapper {
             normalizedTokenAddress,
             eventName,
             indexFilterValues,
-            artifacts.ERC20Token.compilerOutput.abi,
+            ERC20Token.compilerOutput.abi,
             callback,
             isVerbose,
         );
@@ -418,30 +418,19 @@ export class ERC20TokenWrapper extends ContractWrapper {
             eventName,
             blockRange,
             indexFilterValues,
-            artifacts.ERC20Token.compilerOutput.abi,
+            ERC20Token.compilerOutput.abi,
         );
         return logs;
     }
-    // HACK: We don't want this method to be visible to the other units within that package but not to the end user.
-    // TS doesn't give that possibility and therefore we make it private and access it over an any cast. Because of that tslint sees it as unused.
-    // tslint:disable-next-line:no-unused-variable
-    private _invalidateContractInstances(): void {
-        this.unsubscribeAll();
-        this._tokenContractsByAddress = {};
-    }
     private async _getTokenContractAsync(tokenAddress: string): Promise<ERC20TokenContract> {
         const normalizedTokenAddress = tokenAddress.toLowerCase();
         let tokenContract = this._tokenContractsByAddress[normalizedTokenAddress];
         if (!_.isUndefined(tokenContract)) {
             return tokenContract;
         }
-        const [abi, address] = await this._getContractAbiAndAddressFromArtifactsAsync(
-            artifacts.ERC20Token,
-            normalizedTokenAddress,
-        );
         const contractInstance = new ERC20TokenContract(
-            abi,
-            address,
+            this.abi,
+            normalizedTokenAddress,
             this._web3Wrapper.getProvider(),
             this._web3Wrapper.getContractDefaults(),
         );
diff --git a/packages/contract-wrappers/src/contract_wrappers/erc721_proxy_wrapper.ts b/packages/contract-wrappers/src/contract_wrappers/erc721_proxy_wrapper.ts
index 933c1dc27..adee3e3ab 100644
--- a/packages/contract-wrappers/src/contract_wrappers/erc721_proxy_wrapper.ts
+++ b/packages/contract-wrappers/src/contract_wrappers/erc721_proxy_wrapper.ts
@@ -1,38 +1,39 @@
+import { ERC721ProxyContract } from '@0xproject/abi-gen-wrappers';
+import { ERC721Proxy } from '@0xproject/contract-artifacts';
 import { AssetProxyId } from '@0xproject/types';
 import { Web3Wrapper } from '@0xproject/web3-wrapper';
 import { ContractAbi } from 'ethereum-types';
 import * as _ from 'lodash';
 
-import { artifacts } from '../artifacts';
 import { assert } from '../utils/assert';
+import { _getDefaultContractAddresses } from '../utils/contract_addresses';
 
 import { ContractWrapper } from './contract_wrapper';
-import { ERC721ProxyContract } from './generated/erc721_proxy';
 
 /**
  * This class includes the functionality related to interacting with the ERC721Proxy contract.
  */
 export class ERC721ProxyWrapper extends ContractWrapper {
-    public abi: ContractAbi = artifacts.ERC20Proxy.compilerOutput.abi;
+    public abi: ContractAbi = ERC721Proxy.compilerOutput.abi;
+    public address: string;
     private _erc721ProxyContractIfExists?: ERC721ProxyContract;
-    private _contractAddressIfExists?: string;
     /**
      * Instantiate ERC721ProxyWrapper
      * @param web3Wrapper Web3Wrapper instance to use
      * @param networkId Desired networkId
-     * @param contractAddressIfExists The contract address to use. This is usually pulled from
-     * the artifacts but needs to be specified when using with your own custom testnet.
+     * @param address The address of the ERC721Proxy contract. If undefined,
+     * will default to the known address corresponding to the networkId.
      */
-    constructor(web3Wrapper: Web3Wrapper, networkId: number, contractAddressIfExists?: string) {
+    constructor(web3Wrapper: Web3Wrapper, networkId: number, address?: string) {
         super(web3Wrapper, networkId);
-        this._contractAddressIfExists = contractAddressIfExists;
+        this.address = _.isUndefined(address) ? _getDefaultContractAddresses(networkId).erc721Proxy : address;
     }
     /**
      * Get the 4 bytes ID of this asset proxy
      * @return  Proxy id
      */
     public async getProxyIdAsync(): Promise<AssetProxyId> {
-        const ERC721ProxyContractInstance = await this._getERC721ProxyContractAsync();
+        const ERC721ProxyContractInstance = await this._getERC721ProxyContract();
         const proxyId = (await ERC721ProxyContractInstance.getProxyId.callAsync()) as AssetProxyId;
         return proxyId;
     }
@@ -44,7 +45,7 @@ export class ERC721ProxyWrapper extends ContractWrapper {
     public async isAuthorizedAsync(exchangeContractAddress: string): Promise<boolean> {
         assert.isETHAddressHex('exchangeContractAddress', exchangeContractAddress);
         const normalizedExchangeContractAddress = exchangeContractAddress.toLowerCase();
-        const ERC721ProxyContractInstance = await this._getERC721ProxyContractAsync();
+        const ERC721ProxyContractInstance = await this._getERC721ProxyContract();
         const isAuthorized = await ERC721ProxyContractInstance.authorized.callAsync(normalizedExchangeContractAddress);
         return isAuthorized;
     }
@@ -53,36 +54,17 @@ export class ERC721ProxyWrapper extends ContractWrapper {
      * @return  The list of authorized addresses.
      */
     public async getAuthorizedAddressesAsync(): Promise<string[]> {
-        const ERC721ProxyContractInstance = await this._getERC721ProxyContractAsync();
+        const ERC721ProxyContractInstance = await this._getERC721ProxyContract();
         const authorizedAddresses = await ERC721ProxyContractInstance.getAuthorizedAddresses.callAsync();
         return authorizedAddresses;
     }
-    /**
-     * Retrieves the Ethereum address of the ERC721Proxy contract deployed on the network
-     * that the user-passed web3 provider is connected to.
-     * @returns The Ethereum address of the ERC721Proxy contract being used.
-     */
-    public getContractAddress(): string {
-        const contractAddress = this._getContractAddress(artifacts.ERC721Proxy, this._contractAddressIfExists);
-        return contractAddress;
-    }
-    // HACK: We don't want this method to be visible to the other units within that package but not to the end user.
-    // TS doesn't give that possibility and therefore we make it private and access it over an any cast. Because of that tslint sees it as unused.
-    // tslint:disable-next-line:no-unused-variable
-    private _invalidateContractInstance(): void {
-        delete this._erc721ProxyContractIfExists;
-    }
-    private async _getERC721ProxyContractAsync(): Promise<ERC721ProxyContract> {
+    private _getERC721ProxyContract(): ERC721ProxyContract {
         if (!_.isUndefined(this._erc721ProxyContractIfExists)) {
             return this._erc721ProxyContractIfExists;
         }
-        const [abi, address] = await this._getContractAbiAndAddressFromArtifactsAsync(
-            artifacts.ERC721Proxy,
-            this._contractAddressIfExists,
-        );
         const contractInstance = new ERC721ProxyContract(
-            abi,
-            address,
+            this.abi,
+            this.address,
             this._web3Wrapper.getProvider(),
             this._web3Wrapper.getContractDefaults(),
         );
diff --git a/packages/contract-wrappers/src/contract_wrappers/erc721_token_wrapper.ts b/packages/contract-wrappers/src/contract_wrappers/erc721_token_wrapper.ts
index 590dbbf74..d92d7087c 100644
--- a/packages/contract-wrappers/src/contract_wrappers/erc721_token_wrapper.ts
+++ b/packages/contract-wrappers/src/contract_wrappers/erc721_token_wrapper.ts
@@ -1,10 +1,11 @@
+import { ERC721TokenContract, ERC721TokenEventArgs, ERC721TokenEvents } from '@0xproject/abi-gen-wrappers';
+import { ERC721Token } from '@0xproject/contract-artifacts';
 import { schemas } from '@0xproject/json-schemas';
 import { BigNumber } from '@0xproject/utils';
 import { Web3Wrapper } from '@0xproject/web3-wrapper';
 import { ContractAbi, LogWithDecodedArgs } from 'ethereum-types';
 import * as _ from 'lodash';
 
-import { artifacts } from '../artifacts';
 import { methodOptsSchema } from '../schemas/method_opts_schema';
 import { txOptsSchema } from '../schemas/tx_opts_schema';
 import {
@@ -20,7 +21,6 @@ import { constants } from '../utils/constants';
 
 import { ContractWrapper } from './contract_wrapper';
 import { ERC721ProxyWrapper } from './erc721_proxy_wrapper';
-import { ERC721TokenContract, ERC721TokenEventArgs, ERC721TokenEvents } from './generated/erc721_token';
 
 const removeUndefinedProperties = _.pickBy;
 
@@ -30,7 +30,7 @@ const removeUndefinedProperties = _.pickBy;
  * to the 0x ERC721 Proxy smart contract.
  */
 export class ERC721TokenWrapper extends ContractWrapper {
-    public abi: ContractAbi = artifacts.ERC721Token.compilerOutput.abi;
+    public abi: ContractAbi = ERC721Token.compilerOutput.abi;
     private _tokenContractsByAddress: { [address: string]: ERC721TokenContract };
     private _erc721ProxyWrapper: ERC721ProxyWrapper;
     /**
@@ -150,7 +150,7 @@ export class ERC721TokenWrapper extends ContractWrapper {
         ownerAddress: string,
         methodOpts: MethodOpts = {},
     ): Promise<boolean> {
-        const proxyAddress = this._erc721ProxyWrapper.getContractAddress();
+        const proxyAddress = this._erc721ProxyWrapper.address;
         const isProxyApprovedForAll = await this.isApprovedForAllAsync(
             tokenAddress,
             ownerAddress,
@@ -199,7 +199,7 @@ export class ERC721TokenWrapper extends ContractWrapper {
         tokenId: BigNumber,
         methodOpts: MethodOpts = {},
     ): Promise<boolean> {
-        const proxyAddress = this._erc721ProxyWrapper.getContractAddress();
+        const proxyAddress = this._erc721ProxyWrapper.address;
         const approvedAddress = await this.getApprovedIfExistsAsync(tokenAddress, tokenId, methodOpts);
         const isProxyApproved = approvedAddress === proxyAddress;
         return isProxyApproved;
@@ -260,7 +260,7 @@ export class ERC721TokenWrapper extends ContractWrapper {
         isApproved: boolean,
         txOpts: TransactionOpts = {},
     ): Promise<string> {
-        const proxyAddress = this._erc721ProxyWrapper.getContractAddress();
+        const proxyAddress = this._erc721ProxyWrapper.address;
         const txHash = await this.setApprovalForAllAsync(tokenAddress, ownerAddress, proxyAddress, isApproved, txOpts);
         return txHash;
     }
@@ -318,7 +318,7 @@ export class ERC721TokenWrapper extends ContractWrapper {
         tokenId: BigNumber,
         txOpts: TransactionOpts = {},
     ): Promise<string> {
-        const proxyAddress = this._erc721ProxyWrapper.getContractAddress();
+        const proxyAddress = this._erc721ProxyWrapper.address;
         const txHash = await this.setApprovalAsync(tokenAddress, proxyAddress, tokenId, txOpts);
         return txHash;
     }
@@ -400,7 +400,7 @@ export class ERC721TokenWrapper extends ContractWrapper {
             normalizedTokenAddress,
             eventName,
             indexFilterValues,
-            artifacts.ERC721Token.compilerOutput.abi,
+            ERC721Token.compilerOutput.abi,
             callback,
             isVerbose,
         );
@@ -445,30 +445,19 @@ export class ERC721TokenWrapper extends ContractWrapper {
             eventName,
             blockRange,
             indexFilterValues,
-            artifacts.ERC721Token.compilerOutput.abi,
+            ERC721Token.compilerOutput.abi,
         );
         return logs;
     }
-    // HACK: We don't want this method to be visible to the other units within that package but not to the end user.
-    // TS doesn't give that possibility and therefore we make it private and access it over an any cast. Because of that tslint sees it as unused.
-    // tslint:disable-next-line:no-unused-variable
-    private _invalidateContractInstances(): void {
-        this.unsubscribeAll();
-        this._tokenContractsByAddress = {};
-    }
     private async _getTokenContractAsync(tokenAddress: string): Promise<ERC721TokenContract> {
         const normalizedTokenAddress = tokenAddress.toLowerCase();
         let tokenContract = this._tokenContractsByAddress[normalizedTokenAddress];
         if (!_.isUndefined(tokenContract)) {
             return tokenContract;
         }
-        const [abi, address] = await this._getContractAbiAndAddressFromArtifactsAsync(
-            artifacts.ERC721Token,
-            normalizedTokenAddress,
-        );
         const contractInstance = new ERC721TokenContract(
-            abi,
-            address,
+            this.abi,
+            normalizedTokenAddress,
             this._web3Wrapper.getProvider(),
             this._web3Wrapper.getContractDefaults(),
         );
diff --git a/packages/contract-wrappers/src/contract_wrappers/ether_token_wrapper.ts b/packages/contract-wrappers/src/contract_wrappers/ether_token_wrapper.ts
index 1ac01812e..d5775208e 100644
--- a/packages/contract-wrappers/src/contract_wrappers/ether_token_wrapper.ts
+++ b/packages/contract-wrappers/src/contract_wrappers/ether_token_wrapper.ts
@@ -1,16 +1,16 @@
+import { WETH9Contract, WETH9EventArgs, WETH9Events } from '@0xproject/abi-gen-wrappers';
+import { WETH9 } from '@0xproject/contract-artifacts';
 import { schemas } from '@0xproject/json-schemas';
 import { BigNumber } from '@0xproject/utils';
 import { Web3Wrapper } from '@0xproject/web3-wrapper';
 import { ContractAbi, LogWithDecodedArgs } from 'ethereum-types';
 import * as _ from 'lodash';
 
-import { artifacts } from '../artifacts';
 import { BlockRange, ContractWrappersError, EventCallback, IndexedFilterValues, TransactionOpts } from '../types';
 import { assert } from '../utils/assert';
 
 import { ContractWrapper } from './contract_wrapper';
 import { ERC20TokenWrapper } from './erc20_token_wrapper';
-import { WETH9Contract, WETH9EventArgs, WETH9Events } from './generated/weth9';
 
 const removeUndefinedProperties = _.pickBy;
 
@@ -19,7 +19,7 @@ const removeUndefinedProperties = _.pickBy;
  * The caller can convert ETH into the equivalent number of wrapped ETH ERC20 tokens and back.
  */
 export class EtherTokenWrapper extends ContractWrapper {
-    public abi: ContractAbi = artifacts.EtherToken.compilerOutput.abi;
+    public abi: ContractAbi = WETH9.compilerOutput.abi;
     private _etherTokenContractsByAddress: {
         [address: string]: WETH9Contract;
     } = {};
@@ -142,7 +142,7 @@ export class EtherTokenWrapper extends ContractWrapper {
             eventName,
             blockRange,
             indexFilterValues,
-            artifacts.EtherToken.compilerOutput.abi,
+            WETH9.compilerOutput.abi,
         );
         return logs;
     }
@@ -172,7 +172,7 @@ export class EtherTokenWrapper extends ContractWrapper {
             normalizedEtherTokenAddress,
             eventName,
             indexFilterValues,
-            artifacts.EtherToken.compilerOutput.abi,
+            WETH9.compilerOutput.abi,
             callback,
             isVerbose,
         );
@@ -192,36 +192,14 @@ export class EtherTokenWrapper extends ContractWrapper {
     public unsubscribeAll(): void {
         super._unsubscribeAll();
     }
-    /**
-     * Retrieves the Ethereum address of the EtherToken contract deployed on the network
-     * that the user-passed web3 provider is connected to. If it's not Kovan, Ropsten, Rinkeby, Mainnet or TestRPC
-     * (networkId: 50), it will return undefined (e.g a private network).
-     * @returns The Ethereum address of the EtherToken contract or undefined.
-     */
-    public getContractAddressIfExists(): string | undefined {
-        const networkSpecificArtifact = artifacts.EtherToken.networks[this._networkId];
-        const contractAddressIfExists = _.isUndefined(networkSpecificArtifact)
-            ? undefined
-            : networkSpecificArtifact.address;
-        return contractAddressIfExists;
-    }
-    // tslint:disable-next-line:no-unused-variable
-    private _invalidateContractInstance(): void {
-        this.unsubscribeAll();
-        this._etherTokenContractsByAddress = {};
-    }
     private async _getEtherTokenContractAsync(etherTokenAddress: string): Promise<WETH9Contract> {
         let etherTokenContract = this._etherTokenContractsByAddress[etherTokenAddress];
         if (!_.isUndefined(etherTokenContract)) {
             return etherTokenContract;
         }
-        const [abi, address] = await this._getContractAbiAndAddressFromArtifactsAsync(
-            artifacts.EtherToken,
-            etherTokenAddress,
-        );
         const contractInstance = new WETH9Contract(
-            abi,
-            address,
+            this.abi,
+            etherTokenAddress,
             this._web3Wrapper.getProvider(),
             this._web3Wrapper.getContractDefaults(),
         );
diff --git a/packages/contract-wrappers/src/contract_wrappers/exchange_wrapper.ts b/packages/contract-wrappers/src/contract_wrappers/exchange_wrapper.ts
index dc9ffcbf7..9063e0e40 100644
--- a/packages/contract-wrappers/src/contract_wrappers/exchange_wrapper.ts
+++ b/packages/contract-wrappers/src/contract_wrappers/exchange_wrapper.ts
@@ -1,3 +1,5 @@
+import { ExchangeContract, ExchangeEventArgs, ExchangeEvents } from '@0xproject/abi-gen-wrappers';
+import { Exchange } from '@0xproject/contract-artifacts';
 import { schemas } from '@0xproject/json-schemas';
 import {
     assetDataUtils,
@@ -11,7 +13,6 @@ import { Web3Wrapper } from '@0xproject/web3-wrapper';
 import { BlockParamLiteral, ContractAbi, LogWithDecodedArgs } from 'ethereum-types';
 import * as _ from 'lodash';
 
-import { artifacts } from '../artifacts';
 import { AssetBalanceAndProxyAllowanceFetcher } from '../fetchers/asset_balance_and_proxy_allowance_fetcher';
 import { OrderFilledCancelledFetcher } from '../fetchers/order_filled_cancelled_fetcher';
 import { methodOptsSchema } from '../schemas/method_opts_schema';
@@ -24,54 +25,58 @@ import {
     IndexedFilterValues,
     MethodOpts,
     OrderInfo,
-    OrderStatus,
     OrderTransactionOpts,
     ValidateOrderFillableOpts,
 } from '../types';
 import { assert } from '../utils/assert';
+import { _getDefaultContractAddresses } from '../utils/contract_addresses';
 import { decorators } from '../utils/decorators';
 import { TransactionEncoder } from '../utils/transaction_encoder';
 
 import { ContractWrapper } from './contract_wrapper';
 import { ERC20TokenWrapper } from './erc20_token_wrapper';
 import { ERC721TokenWrapper } from './erc721_token_wrapper';
-import { ExchangeContract, ExchangeEventArgs, ExchangeEvents } from './generated/exchange';
 
 /**
  * This class includes all the functionality related to calling methods, sending transactions and subscribing to
  * events of the 0x V2 Exchange smart contract.
  */
 export class ExchangeWrapper extends ContractWrapper {
-    public abi: ContractAbi = artifacts.Exchange.compilerOutput.abi;
+    public abi: ContractAbi = Exchange.compilerOutput.abi;
+    public address: string;
+    public zrxTokenAddress: string;
     private _exchangeContractIfExists?: ExchangeContract;
     private _erc721TokenWrapper: ERC721TokenWrapper;
     private _erc20TokenWrapper: ERC20TokenWrapper;
-    private _contractAddressIfExists?: string;
-    private _zrxContractAddressIfExists?: string;
     /**
      * Instantiate ExchangeWrapper
-     * @param web3Wrapper Web3Wrapper instance to use
-     * @param networkId Desired networkId
-     * @param contractAddressIfExists The exchange contract address to use. This is usually pulled from
-     * the artifacts but needs to be specified when using with your own custom testnet.
-     * @param zrxContractAddressIfExists The ZRXToken contract address to use. This is usually pulled from
-     * the artifacts but needs to be specified when using with your own custom testnet.
-     * @param blockPollingIntervalMs The block polling interval to use for active subscriptions
+     * @param web3Wrapper Web3Wrapper instance to use.
+     * @param networkId Desired networkId.
+     * @param erc20TokenWrapper ERC20TokenWrapper instance to use.
+     * @param erc721TokenWrapper ERC721TokenWrapper instance to use.
+     * @param address The address of the Exchange contract. If undefined, will
+     * default to the known address corresponding to the networkId.
+     * @param zrxTokenAddress The address of the ZRXToken contract. If
+     * undefined, will default to the known address corresponding to the
+     * networkId.
+     * @param blockPollingIntervalMs The block polling interval to use for active subscriptions.
      */
     constructor(
         web3Wrapper: Web3Wrapper,
         networkId: number,
         erc20TokenWrapper: ERC20TokenWrapper,
         erc721TokenWrapper: ERC721TokenWrapper,
-        contractAddressIfExists?: string,
-        zrxContractAddressIfExists?: string,
+        address?: string,
+        zrxTokenAddress?: string,
         blockPollingIntervalMs?: number,
     ) {
         super(web3Wrapper, networkId, blockPollingIntervalMs);
         this._erc20TokenWrapper = erc20TokenWrapper;
         this._erc721TokenWrapper = erc721TokenWrapper;
-        this._contractAddressIfExists = contractAddressIfExists;
-        this._zrxContractAddressIfExists = zrxContractAddressIfExists;
+        this.address = _.isUndefined(address) ? _getDefaultContractAddresses(networkId).exchange : address;
+        this.zrxTokenAddress = _.isUndefined(zrxTokenAddress)
+            ? _getDefaultContractAddresses(networkId).zrxToken
+            : zrxTokenAddress;
     }
     /**
      * Retrieve the address of an asset proxy by signature.
@@ -1051,12 +1056,11 @@ export class ExchangeWrapper extends ContractWrapper {
         assert.doesBelongToStringEnum('eventName', eventName, ExchangeEvents);
         assert.doesConformToSchema('indexFilterValues', indexFilterValues, schemas.indexFilterValuesSchema);
         assert.isFunction('callback', callback);
-        const exchangeContractAddress = this.getContractAddress();
         const subscriptionToken = this._subscribe<ArgsType>(
-            exchangeContractAddress,
+            this.address,
             eventName,
             indexFilterValues,
-            artifacts.Exchange.compilerOutput.abi,
+            Exchange.compilerOutput.abi,
             callback,
             isVerbose,
         );
@@ -1091,13 +1095,12 @@ export class ExchangeWrapper extends ContractWrapper {
         assert.doesBelongToStringEnum('eventName', eventName, ExchangeEvents);
         assert.doesConformToSchema('blockRange', blockRange, schemas.blockRangeSchema);
         assert.doesConformToSchema('indexFilterValues', indexFilterValues, schemas.indexFilterValuesSchema);
-        const exchangeContractAddress = this.getContractAddress();
         const logs = await this._getLogsAsync<ArgsType>(
-            exchangeContractAddress,
+            this.address,
             eventName,
             blockRange,
             indexFilterValues,
-            artifacts.Exchange.compilerOutput.abi,
+            Exchange.compilerOutput.abi,
         );
         return logs;
     }
@@ -1160,29 +1163,11 @@ export class ExchangeWrapper extends ContractWrapper {
         );
     }
     /**
-     * Retrieves the Ethereum address of the Exchange contract deployed on the network
-     * that the user-passed web3 provider is connected to.
-     * @returns The Ethereum address of the Exchange contract being used.
-     */
-    public getContractAddress(): string {
-        const contractAddress = this._getContractAddress(artifacts.Exchange, this._contractAddressIfExists);
-        return contractAddress;
-    }
-    /**
-     * Returns the ZRX token address used by the exchange contract.
-     * @return Address of ZRX token
-     */
-    public getZRXTokenAddress(): string {
-        const contractAddress = this._getContractAddress(artifacts.ZRXToken, this._zrxContractAddressIfExists);
-        return contractAddress;
-    }
-    /**
      * Returns the ZRX asset data used by the exchange contract.
      * @return ZRX asset data
      */
     public getZRXAssetData(): string {
-        const zrxTokenAddress = this.getZRXTokenAddress();
-        const zrxAssetData = assetDataUtils.encodeERC20AssetData(zrxTokenAddress);
+        const zrxAssetData = assetDataUtils.encodeERC20AssetData(this.zrxTokenAddress);
         return zrxAssetData;
     }
     /**
@@ -1195,23 +1180,14 @@ export class ExchangeWrapper extends ContractWrapper {
         const encoder = new TransactionEncoder(exchangeInstance);
         return encoder;
     }
-    // tslint:disable:no-unused-variable
-    private _invalidateContractInstances(): void {
-        this.unsubscribeAll();
-        delete this._exchangeContractIfExists;
-    }
     // tslint:enable:no-unused-variable
     private async _getExchangeContractAsync(): Promise<ExchangeContract> {
         if (!_.isUndefined(this._exchangeContractIfExists)) {
             return this._exchangeContractIfExists;
         }
-        const [abi, address] = await this._getContractAbiAndAddressFromArtifactsAsync(
-            artifacts.Exchange,
-            this._contractAddressIfExists,
-        );
         const contractInstance = new ExchangeContract(
-            abi,
-            address,
+            this.abi,
+            this.address,
             this._web3Wrapper.getProvider(),
             this._web3Wrapper.getContractDefaults(),
         );
diff --git a/packages/contract-wrappers/src/contract_wrappers/forwarder_wrapper.ts b/packages/contract-wrappers/src/contract_wrappers/forwarder_wrapper.ts
index c19edf188..b6fc071ea 100644
--- a/packages/contract-wrappers/src/contract_wrappers/forwarder_wrapper.ts
+++ b/packages/contract-wrappers/src/contract_wrappers/forwarder_wrapper.ts
@@ -1,3 +1,5 @@
+import { ForwarderContract } from '@0xproject/abi-gen-wrappers';
+import { Forwarder } from '@0xproject/contract-artifacts';
 import { schemas } from '@0xproject/json-schemas';
 import { AssetProxyId, SignedOrder } from '@0xproject/types';
 import { BigNumber } from '@0xproject/utils';
@@ -5,36 +7,56 @@ import { Web3Wrapper } from '@0xproject/web3-wrapper';
 import { ContractAbi } from 'ethereum-types';
 import * as _ from 'lodash';
 
-import { artifacts } from '../artifacts';
 import { orderTxOptsSchema } from '../schemas/order_tx_opts_schema';
 import { txOptsSchema } from '../schemas/tx_opts_schema';
 import { OrderTransactionOpts } from '../types';
 import { assert } from '../utils/assert';
 import { calldataOptimizationUtils } from '../utils/calldata_optimization_utils';
 import { constants } from '../utils/constants';
+import { _getDefaultContractAddresses } from '../utils/contract_addresses';
 import { decorators } from '../utils/decorators';
 import { utils } from '../utils/utils';
 
 import { ContractWrapper } from './contract_wrapper';
-import { ForwarderContract } from './generated/forwarder';
 
 /**
  * This class includes the functionality related to interacting with the Forwarder contract.
  */
 export class ForwarderWrapper extends ContractWrapper {
-    public abi: ContractAbi = artifacts.Forwarder.compilerOutput.abi;
+    public abi: ContractAbi = Forwarder.compilerOutput.abi;
+    public address: string;
+    public zrxTokenAddress: string;
+    public etherTokenAddress: string;
     private _forwarderContractIfExists?: ForwarderContract;
-    private _contractAddressIfExists?: string;
-    private _zrxContractAddressIfExists?: string;
+
+    /**
+     * Instantiate ForwarderWrapper
+     * @param web3Wrapper Web3Wrapper instance to use.
+     * @param networkId Desired networkId.
+     * @param address The address of the Exchange contract. If undefined, will
+     * default to the known address corresponding to the networkId.
+     * @param zrxTokenAddress The address of the ZRXToken contract. If
+     * undefined, will default to the known address corresponding to the
+     * networkId.
+     * @param etherTokenAddress The address of a WETH (Ether token) contract. If
+     * undefined, will default to the known address corresponding to the
+     * networkId.
+     */
     constructor(
         web3Wrapper: Web3Wrapper,
         networkId: number,
-        contractAddressIfExists?: string,
-        zrxContractAddressIfExists?: string,
+        address?: string,
+        zrxTokenAddress?: string,
+        etherTokenAddress?: string,
     ) {
         super(web3Wrapper, networkId);
-        this._contractAddressIfExists = contractAddressIfExists;
-        this._zrxContractAddressIfExists = zrxContractAddressIfExists;
+        this.address = _.isUndefined(address) ? _getDefaultContractAddresses(networkId).exchange : address;
+        this.zrxTokenAddress = _.isUndefined(zrxTokenAddress)
+            ? _getDefaultContractAddresses(networkId).zrxToken
+            : zrxTokenAddress;
+        this.etherTokenAddress = _.isUndefined(etherTokenAddress)
+            ? _getDefaultContractAddresses(networkId).etherToken
+            : etherTokenAddress;
     }
     /**
      * Purchases as much of orders' makerAssets as possible by selling up to 95% of transaction's ETH value.
@@ -73,12 +95,8 @@ export class ForwarderWrapper extends ContractWrapper {
         assert.isETHAddressHex('feeRecipientAddress', feeRecipientAddress);
         assert.doesConformToSchema('orderTransactionOpts', orderTransactionOpts, orderTxOptsSchema, [txOptsSchema]);
         // other assertions
-        assert.ordersCanBeUsedForForwarderContract(signedOrders, this.getEtherTokenAddress());
-        assert.feeOrdersCanBeUsedForForwarderContract(
-            signedFeeOrders,
-            this.getZRXTokenAddress(),
-            this.getEtherTokenAddress(),
-        );
+        assert.ordersCanBeUsedForForwarderContract(signedOrders, this.etherTokenAddress);
+        assert.feeOrdersCanBeUsedForForwarderContract(signedFeeOrders, this.zrxTokenAddress, this.etherTokenAddress);
         // format feePercentage
         const formattedFeePercentage = utils.numberPercentageToEtherTokenAmountPercentage(feePercentage);
         // lowercase input addresses
@@ -165,12 +183,8 @@ export class ForwarderWrapper extends ContractWrapper {
         assert.isETHAddressHex('feeRecipientAddress', feeRecipientAddress);
         assert.doesConformToSchema('orderTransactionOpts', orderTransactionOpts, orderTxOptsSchema, [txOptsSchema]);
         // other assertions
-        assert.ordersCanBeUsedForForwarderContract(signedOrders, this.getEtherTokenAddress());
-        assert.feeOrdersCanBeUsedForForwarderContract(
-            signedFeeOrders,
-            this.getZRXTokenAddress(),
-            this.getEtherTokenAddress(),
-        );
+        assert.ordersCanBeUsedForForwarderContract(signedOrders, this.etherTokenAddress);
+        assert.feeOrdersCanBeUsedForForwarderContract(signedFeeOrders, this.zrxTokenAddress, this.etherTokenAddress);
         // format feePercentage
         const formattedFeePercentage = utils.numberPercentageToEtherTokenAmountPercentage(feePercentage);
         // lowercase input addresses
@@ -220,48 +234,13 @@ export class ForwarderWrapper extends ContractWrapper {
         );
         return txHash;
     }
-    /**
-     * Retrieves the Ethereum address of the Forwarder contract deployed on the network
-     * that the user-passed web3 provider is connected to.
-     * @returns The Ethereum address of the Forwarder contract being used.
-     */
-    public getContractAddress(): string {
-        const contractAddress = this._getContractAddress(artifacts.Forwarder, this._contractAddressIfExists);
-        return contractAddress;
-    }
-    /**
-     * Returns the ZRX token address used by the forwarder contract.
-     * @return Address of ZRX token
-     */
-    public getZRXTokenAddress(): string {
-        const contractAddress = this._getContractAddress(artifacts.ZRXToken, this._zrxContractAddressIfExists);
-        return contractAddress;
-    }
-    /**
-     * Returns the Ether token address used by the forwarder contract.
-     * @return Address of Ether token
-     */
-    public getEtherTokenAddress(): string {
-        const contractAddress = this._getContractAddress(artifacts.EtherToken);
-        return contractAddress;
-    }
-    // HACK: We don't want this method to be visible to the other units within that package but not to the end user.
-    // TS doesn't give that possibility and therefore we make it private and access it over an any cast. Because of that tslint sees it as unused.
-    // tslint:disable-next-line:no-unused-variable
-    private _invalidateContractInstance(): void {
-        delete this._forwarderContractIfExists;
-    }
     private async _getForwarderContractAsync(): Promise<ForwarderContract> {
         if (!_.isUndefined(this._forwarderContractIfExists)) {
             return this._forwarderContractIfExists;
         }
-        const [abi, address] = await this._getContractAbiAndAddressFromArtifactsAsync(
-            artifacts.Forwarder,
-            this._contractAddressIfExists,
-        );
         const contractInstance = new ForwarderContract(
-            abi,
-            address,
+            this.abi,
+            this.address,
             this._web3Wrapper.getProvider(),
             this._web3Wrapper.getContractDefaults(),
         );
diff --git a/packages/contract-wrappers/src/contract_wrappers/order_validator_wrapper.ts b/packages/contract-wrappers/src/contract_wrappers/order_validator_wrapper.ts
index 1da88f624..2ae1a158b 100644
--- a/packages/contract-wrappers/src/contract_wrappers/order_validator_wrapper.ts
+++ b/packages/contract-wrappers/src/contract_wrappers/order_validator_wrapper.ts
@@ -1,3 +1,5 @@
+import { OrderValidatorContract } from '@0xproject/abi-gen-wrappers';
+import { OrderValidator } from '@0xproject/contract-artifacts';
 import { schemas } from '@0xproject/json-schemas';
 import { SignedOrder } from '@0xproject/types';
 import { BigNumber } from '@0xproject/utils';
@@ -5,26 +7,29 @@ import { Web3Wrapper } from '@0xproject/web3-wrapper';
 import { ContractAbi } from 'ethereum-types';
 import * as _ from 'lodash';
 
-import { artifacts } from '../artifacts';
 import { BalanceAndAllowance, OrderAndTraderInfo, TraderInfo } from '../types';
 import { assert } from '../utils/assert';
+import { _getDefaultContractAddresses } from '../utils/contract_addresses';
 
 import { ContractWrapper } from './contract_wrapper';
-import { OrderValidatorContract } from './generated/order_validator';
 
 /**
  * This class includes the functionality related to interacting with the OrderValidator contract.
  */
 export class OrderValidatorWrapper extends ContractWrapper {
-    public abi: ContractAbi = artifacts.OrderValidator.compilerOutput.abi;
+    public abi: ContractAbi = OrderValidator.compilerOutput.abi;
+    public address: string;
     private _orderValidatorContractIfExists?: OrderValidatorContract;
     /**
      * Instantiate OrderValidatorWrapper
-     * @param web3Wrapper Web3Wrapper instance to use
-     * @param networkId Desired networkId
+     * @param web3Wrapper Web3Wrapper instance to use.
+     * @param networkId Desired networkId.
+     * @param address The address of the OrderValidator contract. If undefined,
+     * will default to the known address corresponding to the networkId.
      */
-    constructor(web3Wrapper: Web3Wrapper, networkId: number) {
+    constructor(web3Wrapper: Web3Wrapper, networkId: number, address?: string) {
         super(web3Wrapper, networkId);
+        this.address = _.isUndefined(address) ? _getDefaultContractAddresses(networkId).exchange : address;
     }
     /**
      * Get an object conforming to OrderAndTraderInfo containing on-chain information of the provided order and address
@@ -164,20 +169,13 @@ export class OrderValidatorWrapper extends ContractWrapper {
         const result = await OrderValidatorContractInstance.getERC721TokenOwner.callAsync(tokenAddress, tokenId);
         return result;
     }
-    // HACK: We don't want this method to be visible to the other units within that package but not to the end user.
-    // TS doesn't give that possibility and therefore we make it private and access it over an any cast. Because of that tslint sees it as unused.
-    // tslint:disable-next-line:no-unused-variable
-    private _invalidateContractInstance(): void {
-        delete this._orderValidatorContractIfExists;
-    }
     private async _getOrderValidatorContractAsync(): Promise<OrderValidatorContract> {
         if (!_.isUndefined(this._orderValidatorContractIfExists)) {
             return this._orderValidatorContractIfExists;
         }
-        const [abi, address] = await this._getContractAbiAndAddressFromArtifactsAsync(artifacts.OrderValidator);
         const contractInstance = new OrderValidatorContract(
-            abi,
-            address,
+            this.abi,
+            this.address,
             this._web3Wrapper.getProvider(),
             this._web3Wrapper.getContractDefaults(),
         );