Switch over to Lerna + Yarn Workspaces setup for a mono-repo approach

packages/0x.js/src/contract_wrappers/token_transfer_proxy_wrapper.ts

@@ -0,0 +1,60 @@
+import * as _ from 'lodash';
+import {Web3Wrapper} from '../web3_wrapper';
+import {ContractWrapper} from './contract_wrapper';
+import {artifacts} from '../artifacts';
+import {TokenTransferProxyContract} from '../types';
+
+/**
+ * This class includes the functionality related to interacting with the TokenTransferProxy contract.
+ */
+export class TokenTransferProxyWrapper extends ContractWrapper {
+    private _tokenTransferProxyContractIfExists?: TokenTransferProxyContract;
+    private _tokenTransferProxyContractAddressFetcher: () => Promise<string>;
+    constructor(web3Wrapper: Web3Wrapper, tokenTransferProxyContractAddressFetcher: () => Promise<string>) {
+        super(web3Wrapper);
+        this._tokenTransferProxyContractAddressFetcher = tokenTransferProxyContractAddressFetcher;
+    }
+    /**
+     * Check if the Exchange contract address is authorized by the TokenTransferProxy contract.
+     * @param   exchangeContractAddress     The hex encoded address of the Exchange contract to call.
+     * @return  Whether the exchangeContractAddress is authorized.
+     */
+    public async isAuthorizedAsync(exchangeContractAddress: string): Promise<boolean> {
+        const tokenTransferProxyContractInstance = await this._getTokenTransferProxyContractAsync();
+        const isAuthorized = await tokenTransferProxyContractInstance.authorized.callAsync(exchangeContractAddress);
+        return isAuthorized;
+    }
+    /**
+     * Get the list of all Exchange contract addresses authorized by the TokenTransferProxy contract.
+     * @return  The list of authorized addresses.
+     */
+    public async getAuthorizedAddressesAsync(): Promise<string[]> {
+        const tokenTransferProxyContractInstance = await this._getTokenTransferProxyContractAsync();
+        const authorizedAddresses = await tokenTransferProxyContractInstance.getAuthorizedAddresses.callAsync();
+        return authorizedAddresses;
+    }
+    /**
+     * Retrieves the Ethereum address of the TokenTransferProxy contract deployed on the network
+     * that the user-passed web3 provider is connected to.
+     * @returns The Ethereum address of the TokenTransferProxy contract being used.
+     */
+    public async getContractAddressAsync(): Promise<string> {
+        const proxyInstance = await this._getTokenTransferProxyContractAsync();
+        const proxyAddress = proxyInstance.address;
+        return proxyAddress;
+    }
+    private _invalidateContractInstance(): void {
+        delete this._tokenTransferProxyContractIfExists;
+    }
+    private async _getTokenTransferProxyContractAsync(): Promise<TokenTransferProxyContract> {
+        if (!_.isUndefined(this._tokenTransferProxyContractIfExists)) {
+            return this._tokenTransferProxyContractIfExists;
+        }
+        const contractAddress = await this._tokenTransferProxyContractAddressFetcher();
+        const contractInstance = await this._instantiateContractIfExistsAsync<TokenTransferProxyContract>(
+            artifacts.TokenTransferProxyArtifact, contractAddress,
+        );
+        this._tokenTransferProxyContractIfExists = contractInstance as TokenTransferProxyContract;
+        return this._tokenTransferProxyContractIfExists;
+    }
+}