13 files changed, 735 insertions, 0 deletions
diff --git a/packages/contracts/util/artifacts.ts b/packages/contracts/util/artifacts.ts
new file mode 100644
index 000000000..8114972d0
--- /dev/null
+++ b/packages/contracts/util/artifacts.ts
@@ -0,0 +1,25 @@
+export class Artifacts {
+  public Migrations: any;
+  public TokenTransferProxy: any;
+  public TokenRegistry: any;
+  public MultiSigWalletWithTimeLock: any;
+  public Exchange: any;
+  public ZRXToken: any;
+  public DummyToken: any;
+  public EtherToken: any;
+  public MultiSigWalletWithTimeLockExceptRemoveAuthorizedAddress: any;
+  public MaliciousToken: any;
+  constructor(artifacts: any) {
+    this.Migrations = artifacts.require('Migrations');
+    this.TokenTransferProxy = artifacts.require('TokenTransferProxy');
+    this.TokenRegistry = artifacts.require('TokenRegistry');
+    this.MultiSigWalletWithTimeLock = artifacts.require('MultiSigWalletWithTimeLock');
+    this.Exchange = artifacts.require('Exchange');
+    this.ZRXToken = artifacts.require('ZRXToken');
+    this.DummyToken = artifacts.require('DummyToken');
+    this.EtherToken = artifacts.require('EtherToken');
+    this.MultiSigWalletWithTimeLockExceptRemoveAuthorizedAddress = artifacts.require(
+        'MultiSigWalletWithTimeLockExceptRemoveAuthorizedAddress');
+    this.MaliciousToken = artifacts.require('MaliciousToken');
+  }
+}
diff --git a/packages/contracts/util/balances.ts b/packages/contracts/util/balances.ts
new file mode 100644
index 000000000..ef4abd7bf
--- /dev/null
+++ b/packages/contracts/util/balances.ts
@@ -0,0 +1,30 @@
+import {BigNumber} from 'bignumber.js';
+import * as _ from 'lodash';
+
+import {bigNumberConfigs} from './bignumber_config';
+import {BalancesByOwner, ContractInstance} from './types';
+
+bigNumberConfigs.configure();
+
+export class Balances {
+  private tokenContractInstances: ContractInstance[];
+  private ownerAddresses: string[];
+  constructor(tokenContractInstances: ContractInstance[], ownerAddresses: string[]) {
+    this.tokenContractInstances = tokenContractInstances;
+    this.ownerAddresses = ownerAddresses;
+  }
+  public async getAsync(): Promise<BalancesByOwner> {
+    const balancesByOwner: BalancesByOwner = {};
+    for (const tokenContractInstance of this.tokenContractInstances) {
+      for (const ownerAddress of this.ownerAddresses) {
+        let balance = await tokenContractInstance.balanceOf(ownerAddress);
+        balance = new BigNumber(balance);
+        if (_.isUndefined(balancesByOwner[ownerAddress])) {
+          balancesByOwner[ownerAddress] = {};
+        }
+        balancesByOwner[ownerAddress][tokenContractInstance.address] = balance;
+      }
+    }
+    return balancesByOwner;
+  }
+}
diff --git a/packages/contracts/util/bignumber_config.ts b/packages/contracts/util/bignumber_config.ts
new file mode 100644
index 000000000..38f59d341
--- /dev/null
+++ b/packages/contracts/util/bignumber_config.ts
@@ -0,0 +1,11 @@
+import {BigNumber} from 'bignumber.js';
+
+export const bigNumberConfigs = {
+    configure() {
+        // By default BigNumber's `toString` method converts to exponential notation if the value has
+        // more then 20 digits. We want to avoid this behavior, so we set EXPONENTIAL_AT to a high number
+        BigNumber.config({
+            EXPONENTIAL_AT: 1000,
+        });
+    },
+};
diff --git a/packages/contracts/util/constants.ts b/packages/contracts/util/constants.ts
new file mode 100644
index 000000000..5beebc68c
--- /dev/null
+++ b/packages/contracts/util/constants.ts
@@ -0,0 +1,4 @@
+export const constants = {
+    NULL_BYTES: '0x',
+    INVALID_OPCODE: 'invalid opcode',
+};
diff --git a/packages/contracts/util/crypto.ts b/packages/contracts/util/crypto.ts
new file mode 100644
index 000000000..e4baee021
--- /dev/null
+++ b/packages/contracts/util/crypto.ts
@@ -0,0 +1,38 @@
+import {BigNumber} from 'bignumber.js';
+import BN = require('bn.js');
+import ABI = require('ethereumjs-abi');
+import ethUtil = require('ethereumjs-util');
+import * as _ from 'lodash';
+
+export const crypto = {
+  /*
+   * We convert types from JS to Solidity as follows:
+   * BigNumber -> uint256
+   * number -> uint8
+   * string -> string
+   * boolean -> bool
+   * valid Ethereum address -> address
+   */
+  solSHA3(args: any[]): Buffer {
+    const argTypes: string[] = [];
+    _.each(args, (arg, i) => {
+      const isNumber = _.isFinite(arg);
+      if (isNumber) {
+        argTypes.push('uint8');
+      } else if ((arg).isBigNumber) {
+        argTypes.push('uint256');
+        args[i] = new BN(arg.toString(10), 10);
+      } else if (ethUtil.isValidAddress(arg)) {
+        argTypes.push('address');
+      } else if (_.isString(arg)) {
+        argTypes.push('string');
+      } else if  (_.isBoolean(arg)) {
+        argTypes.push('bool');
+      } else {
+        throw new Error(`Unable to guess arg type: ${arg}`);
+      }
+    });
+    const hash = ABI.soliditySHA3(argTypes, args);
+    return hash;
+  },
+};
diff --git a/packages/contracts/util/exchange_wrapper.ts b/packages/contracts/util/exchange_wrapper.ts
new file mode 100644
index 000000000..062ea292b
--- /dev/null
+++ b/packages/contracts/util/exchange_wrapper.ts
@@ -0,0 +1,168 @@
+import {BigNumber} from 'bignumber.js';
+import * as _ from 'lodash';
+
+import {formatters} from './formatters';
+import {Order} from './order';
+import {ContractInstance} from './types';
+
+export class ExchangeWrapper {
+  private exchange: ContractInstance;
+  constructor(exchangeContractInstance: ContractInstance) {
+    this.exchange = exchangeContractInstance;
+  }
+  public async fillOrderAsync(order: Order, from: string,
+                              opts: {
+                                  fillTakerTokenAmount?: BigNumber;
+                                  shouldThrowOnInsufficientBalanceOrAllowance?: boolean;
+                              } = {}) {
+    const shouldThrowOnInsufficientBalanceOrAllowance = !!opts.shouldThrowOnInsufficientBalanceOrAllowance;
+    const params = order.createFill(shouldThrowOnInsufficientBalanceOrAllowance, opts.fillTakerTokenAmount);
+    const tx = await this.exchange.fillOrder(
+      params.orderAddresses,
+      params.orderValues,
+      params.fillTakerTokenAmount,
+      params.shouldThrowOnInsufficientBalanceOrAllowance,
+      params.v,
+      params.r,
+      params.s,
+      {from},
+    );
+    _.each(tx.logs, log => wrapLogBigNumbers(log));
+    return tx;
+  }
+  public async cancelOrderAsync(order: Order, from: string,
+                                opts: {cancelTakerTokenAmount?: BigNumber} = {}) {
+    const params = order.createCancel(opts.cancelTakerTokenAmount);
+    const tx = await this.exchange.cancelOrder(
+      params.orderAddresses,
+      params.orderValues,
+      params.cancelTakerTokenAmount,
+      {from},
+    );
+    _.each(tx.logs, log => wrapLogBigNumbers(log));
+    return tx;
+  }
+  public async fillOrKillOrderAsync(order: Order, from: string,
+                                    opts: {fillTakerTokenAmount?: BigNumber} = {}) {
+    const shouldThrowOnInsufficientBalanceOrAllowance = true;
+    const params = order.createFill(shouldThrowOnInsufficientBalanceOrAllowance, opts.fillTakerTokenAmount);
+    const tx = await this.exchange.fillOrKillOrder(
+      params.orderAddresses,
+      params.orderValues,
+      params.fillTakerTokenAmount,
+      params.v,
+      params.r,
+      params.s,
+      {from},
+    );
+    _.each(tx.logs, log => wrapLogBigNumbers(log));
+    return tx;
+  }
+  public async batchFillOrdersAsync(orders: Order[], from: string,
+                                    opts: {
+                                        fillTakerTokenAmounts?: BigNumber[];
+                                        shouldThrowOnInsufficientBalanceOrAllowance?: boolean;
+                                    } = {}) {
+    const shouldThrowOnInsufficientBalanceOrAllowance = !!opts.shouldThrowOnInsufficientBalanceOrAllowance;
+    const params = formatters.createBatchFill(
+        orders, shouldThrowOnInsufficientBalanceOrAllowance, opts.fillTakerTokenAmounts);
+    const tx = await this.exchange.batchFillOrders(
+      params.orderAddresses,
+      params.orderValues,
+      params.fillTakerTokenAmounts,
+      params.shouldThrowOnInsufficientBalanceOrAllowance,
+      params.v,
+      params.r,
+      params.s,
+      {from},
+    );
+    _.each(tx.logs, log => wrapLogBigNumbers(log));
+    return tx;
+  }
+  public async batchFillOrKillOrdersAsync(orders: Order[], from: string,
+                                          opts: {
+                                              fillTakerTokenAmounts?: BigNumber[];
+                                          } = {}) {
+    const params = formatters.createBatchFill(orders, undefined, opts.fillTakerTokenAmounts);
+    const tx = await this.exchange.batchFillOrKillOrders(
+      params.orderAddresses,
+      params.orderValues,
+      params.fillTakerTokenAmounts,
+      params.v,
+      params.r,
+      params.s,
+      {from},
+    );
+    _.each(tx.logs, log => wrapLogBigNumbers(log));
+    return tx;
+  }
+  public async fillOrdersUpToAsync(orders: Order[], from: string,
+                                   opts: {fillTakerTokenAmount?: BigNumber;
+                                          shouldThrowOnInsufficientBalanceOrAllowance?: boolean;
+                                   } = {}) {
+    const shouldThrowOnInsufficientBalanceOrAllowance = !!opts.shouldThrowOnInsufficientBalanceOrAllowance;
+    const params = formatters.createFillUpTo(orders,
+                                             shouldThrowOnInsufficientBalanceOrAllowance,
+                                             opts.fillTakerTokenAmount);
+    const tx = await this.exchange.fillOrdersUpTo(
+      params.orderAddresses,
+      params.orderValues,
+      params.fillTakerTokenAmount,
+      params.shouldThrowOnInsufficientBalanceOrAllowance,
+      params.v,
+      params.r,
+      params.s,
+      {from},
+    );
+    _.each(tx.logs, log => wrapLogBigNumbers(log));
+    return tx;
+  }
+  public async batchCancelOrdersAsync(orders: Order[], from: string,
+                                      opts: {cancelTakerTokenAmounts?: BigNumber[]} = {}) {
+    const params = formatters.createBatchCancel(orders, opts.cancelTakerTokenAmounts);
+    const tx = await this.exchange.batchCancelOrders(
+      params.orderAddresses,
+      params.orderValues,
+      params.cancelTakerTokenAmounts,
+      {from},
+    );
+    _.each(tx.logs, log => wrapLogBigNumbers(log));
+    return tx;
+  }
+  public async getOrderHashAsync(order: Order): Promise<string> {
+    const shouldThrowOnInsufficientBalanceOrAllowance = false;
+    const params = order.createFill(shouldThrowOnInsufficientBalanceOrAllowance);
+    const orderHash = await this.exchange.getOrderHash(params.orderAddresses, params.orderValues);
+    return orderHash;
+  }
+  public async isValidSignatureAsync(order: Order): Promise<boolean> {
+    const isValidSignature = await this.exchange.isValidSignature(
+      order.params.maker,
+      order.params.orderHashHex,
+      order.params.v,
+      order.params.r,
+      order.params.s,
+    );
+    return isValidSignature;
+  }
+  public async isRoundingErrorAsync(numerator: BigNumber, denominator: BigNumber,
+                                    target: BigNumber): Promise<boolean> {
+    const isRoundingError = await this.exchange.isRoundingError(numerator, denominator, target);
+    return isRoundingError;
+  }
+  public async getPartialAmountAsync(numerator: BigNumber, denominator: BigNumber,
+                                     target: BigNumber): Promise<BigNumber> {
+    const partialAmount = new BigNumber(await this.exchange.getPartialAmount(numerator, denominator, target));
+    return partialAmount;
+  }
+}
+
+function wrapLogBigNumbers(log: any): any {
+  const argNames = _.keys(log.args);
+  for (const argName of argNames) {
+    const isWeb3BigNumber = _.startsWith(log.args[argName].constructor.toString(), 'function BigNumber(');
+    if (isWeb3BigNumber) {
+      log.args[argName] = new BigNumber(log.args[argName]);
+    }
+  }
+}
diff --git a/packages/contracts/util/formatters.ts b/packages/contracts/util/formatters.ts
new file mode 100644
index 000000000..cda548617
--- /dev/null
+++ b/packages/contracts/util/formatters.ts
@@ -0,0 +1,74 @@
+import {BigNumber} from 'bignumber.js';
+import * as _ from 'lodash';
+
+import {Order} from './order';
+import {BatchCancelOrders, BatchFillOrders, FillOrdersUpTo} from './types';
+
+export const formatters = {
+  createBatchFill(orders: Order[],
+                  shouldThrowOnInsufficientBalanceOrAllowance: boolean,
+                  fillTakerTokenAmounts: BigNumber[] = []) {
+    const batchFill: BatchFillOrders = {
+      orderAddresses: [],
+      orderValues: [],
+      fillTakerTokenAmounts,
+      shouldThrowOnInsufficientBalanceOrAllowance,
+      v: [],
+      r: [],
+      s: [],
+    };
+    _.forEach(orders, order => {
+      batchFill.orderAddresses.push([order.params.maker, order.params.taker, order.params.makerToken,
+                                     order.params.takerToken, order.params.feeRecipient]);
+      batchFill.orderValues.push([order.params.makerTokenAmount, order.params.takerTokenAmount, order.params.makerFee,
+                                  order.params.takerFee, order.params.expirationTimestampInSec, order.params.salt]);
+      batchFill.v.push(order.params.v);
+      batchFill.r.push(order.params.r);
+      batchFill.s.push(order.params.s);
+      if (fillTakerTokenAmounts.length < orders.length) {
+        batchFill.fillTakerTokenAmounts.push(order.params.takerTokenAmount);
+      }
+    });
+    return batchFill;
+  },
+  createFillUpTo(orders: Order[],
+                 shouldThrowOnInsufficientBalanceOrAllowance: boolean,
+                 fillTakerTokenAmount: BigNumber) {
+    const fillUpTo: FillOrdersUpTo = {
+      orderAddresses: [],
+      orderValues: [],
+      fillTakerTokenAmount,
+      shouldThrowOnInsufficientBalanceOrAllowance,
+      v: [],
+      r: [],
+      s: [],
+    };
+    orders.forEach(order => {
+      fillUpTo.orderAddresses.push([order.params.maker, order.params.taker, order.params.makerToken,
+                                    order.params.takerToken, order.params.feeRecipient]);
+      fillUpTo.orderValues.push([order.params.makerTokenAmount, order.params.takerTokenAmount, order.params.makerFee,
+                                 order.params.takerFee, order.params.expirationTimestampInSec, order.params.salt]);
+      fillUpTo.v.push(order.params.v);
+      fillUpTo.r.push(order.params.r);
+      fillUpTo.s.push(order.params.s);
+    });
+    return fillUpTo;
+  },
+  createBatchCancel(orders: Order[], cancelTakerTokenAmounts: BigNumber[] = []) {
+    const batchCancel: BatchCancelOrders = {
+      orderAddresses: [],
+      orderValues: [],
+      cancelTakerTokenAmounts,
+    };
+    orders.forEach(order => {
+      batchCancel.orderAddresses.push([order.params.maker, order.params.taker, order.params.makerToken,
+                                       order.params.takerToken, order.params.feeRecipient]);
+      batchCancel.orderValues.push([order.params.makerTokenAmount, order.params.takerTokenAmount, order.params.makerFee,
+                                    order.params.takerFee, order.params.expirationTimestampInSec, order.params.salt]);
+      if (cancelTakerTokenAmounts.length < orders.length) {
+        batchCancel.cancelTakerTokenAmounts.push(order.params.takerTokenAmount);
+      }
+    });
+    return batchCancel;
+  },
+};
diff --git a/packages/contracts/util/multi_sig_wrapper.ts b/packages/contracts/util/multi_sig_wrapper.ts
new file mode 100644
index 000000000..7c13dae97
--- /dev/null
+++ b/packages/contracts/util/multi_sig_wrapper.ts
@@ -0,0 +1,34 @@
+import ABI = require('ethereumjs-abi');
+import ethUtil = require('ethereumjs-util');
+import * as _ from 'lodash';
+import * as Web3 from 'web3';
+
+import {ContractInstance, TransactionDataParams} from './types';
+
+export class MultiSigWrapper {
+  private multiSig: ContractInstance;
+  constructor(multiSigContractInstance: ContractInstance) {
+    this.multiSig = multiSigContractInstance;
+  }
+  public async submitTransactionAsync(destination: string, from: string,
+                                      dataParams: TransactionDataParams,
+                                      value: number = 0) {
+    const {name, abi, args = []} = dataParams;
+    const encoded = this.encodeFnArgs(name, abi, args);
+    return this.multiSig.submitTransaction(destination, value, encoded, {from});
+  }
+  public encodeFnArgs(name: string, abi: Web3.AbiDefinition[], args: any[]) {
+    const abiEntity = _.find(abi, {name}) as Web3.MethodAbi;
+    if (_.isUndefined(abiEntity)) {
+      throw new Error(`Did not find abi entry for name: ${name}`);
+    }
+    const types = _.map(abiEntity.inputs, input => input.type);
+    const funcSig = ethUtil.bufferToHex(ABI.methodID(name, types));
+    const argsData = _.map(args, arg => {
+      const target = _.isBoolean(arg) ? +arg : arg;
+      const targetBuff = ethUtil.toBuffer(target);
+      return ethUtil.setLengthLeft(targetBuff, 32).toString('hex');
+    });
+    return funcSig + argsData.join('');
+  }
+}
diff --git a/packages/contracts/util/order.ts b/packages/contracts/util/order.ts
new file mode 100644
index 000000000..635999348
--- /dev/null
+++ b/packages/contracts/util/order.ts
@@ -0,0 +1,109 @@
+import {BigNumber} from 'bignumber.js';
+import promisify = require('es6-promisify');
+import ethUtil = require('ethereumjs-util');
+import * as _ from 'lodash';
+import Web3 = require('web3');
+
+import {crypto} from './crypto';
+import {OrderParams} from './types';
+
+// In order to benefit from type-safety, we re-assign the global web3 instance injected by Truffle
+// with type `any` to a variable of type `Web3`.
+const web3: Web3 = (global as any).web3;
+
+export class Order {
+  public params: OrderParams;
+  constructor(params: OrderParams) {
+    this.params = params;
+  }
+  public isValidSignature() {
+    const {v, r, s} = this.params;
+    if (_.isUndefined(v) || _.isUndefined(r) || _.isUndefined(s)) {
+      throw new Error('Cannot call isValidSignature on unsigned order');
+    }
+    const orderHash = this.getOrderHash();
+    const msgHash = ethUtil.hashPersonalMessage(ethUtil.toBuffer(orderHash));
+    try {
+      const pubKey = ethUtil.ecrecover(msgHash, v, ethUtil.toBuffer(r), ethUtil.toBuffer(s));
+      const recoveredAddress = ethUtil.bufferToHex(ethUtil.pubToAddress(pubKey));
+      return recoveredAddress === this.params.maker;
+    } catch (err) {
+      return false;
+    }
+  }
+  public async signAsync() {
+    const orderHash = this.getOrderHash();
+    const signature = await promisify(web3.eth.sign)(this.params.maker, orderHash);
+    const {v, r, s} = ethUtil.fromRpcSig(signature);
+    this.params = _.assign(this.params, {
+      orderHashHex: orderHash,
+      v,
+      r: ethUtil.bufferToHex(r),
+      s: ethUtil.bufferToHex(s),
+    });
+  }
+  public createFill(shouldThrowOnInsufficientBalanceOrAllowance?: boolean, fillTakerTokenAmount?: BigNumber) {
+    const fill = {
+      orderAddresses: [
+        this.params.maker,
+        this.params.taker,
+        this.params.makerToken,
+        this.params.takerToken,
+        this.params.feeRecipient,
+      ],
+      orderValues: [
+        this.params.makerTokenAmount,
+        this.params.takerTokenAmount,
+        this.params.makerFee,
+        this.params.takerFee,
+        this.params.expirationTimestampInSec,
+        this.params.salt,
+      ],
+      fillTakerTokenAmount: fillTakerTokenAmount || this.params.takerTokenAmount,
+      shouldThrowOnInsufficientBalanceOrAllowance: !!shouldThrowOnInsufficientBalanceOrAllowance,
+      v: this.params.v,
+      r: this.params.r,
+      s: this.params.s,
+    };
+    return fill;
+  }
+  public createCancel(cancelTakerTokenAmount?: BigNumber) {
+    const cancel = {
+      orderAddresses: [
+        this.params.maker,
+        this.params.taker,
+        this.params.makerToken,
+        this.params.takerToken,
+        this.params.feeRecipient,
+      ],
+      orderValues: [
+        this.params.makerTokenAmount,
+        this.params.takerTokenAmount,
+        this.params.makerFee,
+        this.params.takerFee,
+        this.params.expirationTimestampInSec,
+        this.params.salt,
+      ],
+      cancelTakerTokenAmount: cancelTakerTokenAmount || this.params.takerTokenAmount,
+    };
+    return cancel;
+  }
+  private getOrderHash(): string {
+    const orderHash = crypto.solSHA3([
+      this.params.exchangeContractAddress,
+      this.params.maker,
+      this.params.taker,
+      this.params.makerToken,
+      this.params.takerToken,
+      this.params.feeRecipient,
+      this.params.makerTokenAmount,
+      this.params.takerTokenAmount,
+      this.params.makerFee,
+      this.params.takerFee,
+      this.params.expirationTimestampInSec,
+      this.params.salt,
+    ]);
+    const orderHashHex = ethUtil.bufferToHex(orderHash);
+    return orderHashHex;
+  }
+}
diff --git a/packages/contracts/util/order_factory.ts b/packages/contracts/util/order_factory.ts
new file mode 100644
index 000000000..cdce7d18a
--- /dev/null
+++ b/packages/contracts/util/order_factory.ts
@@ -0,0 +1,24 @@
+import {ZeroEx} from '0x.js';
+import {BigNumber} from 'bignumber.js';
+import * as _ from 'lodash';
+
+import {Order} from './order';
+import {DefaultOrderParams, OptionalOrderParams, OrderParams} from './types';
+
+export class OrderFactory {
+  private defaultOrderParams: DefaultOrderParams;
+  constructor(defaultOrderParams: DefaultOrderParams) {
+    this.defaultOrderParams = defaultOrderParams;
+  }
+  public async newSignedOrderAsync(customOrderParams: OptionalOrderParams = {}) {
+    const randomExpiration = new BigNumber(Math.floor((Date.now() + (Math.random() * 100000000000)) / 1000));
+    const orderParams: OrderParams = _.assign({}, {
+      expirationTimestampInSec: randomExpiration,
+      salt: ZeroEx.generatePseudoRandomSalt(),
+      taker: ZeroEx.NULL_ADDRESS,
+    }, this.defaultOrderParams, customOrderParams);
+    const order = new Order(orderParams);
+    await order.signAsync();
+    return order;
+  }
+}
diff --git a/packages/contracts/util/rpc.ts b/packages/contracts/util/rpc.ts
new file mode 100644
index 000000000..37643874c
--- /dev/null
+++ b/packages/contracts/util/rpc.ts
@@ -0,0 +1,43 @@
+import 'isomorphic-fetch';
+
+import * as truffleConf from '../truffle.js';
+
+export class RPC {
+  private host: string;
+  private port: number;
+  private id: number;
+  constructor() {
+    this.host = truffleConf.networks.development.host;
+    this.port = truffleConf.networks.development.port;
+    this.id = 0;
+  }
+  public async increaseTimeAsync(time: number) {
+    const method = 'evm_increaseTime';
+    const params = [time];
+    const payload = this.toPayload(method, params);
+    return this.sendAsync(payload);
+  }
+  public async mineBlockAsync() {
+    const method = 'evm_mine';
+    const payload = this.toPayload(method);
+    return this.sendAsync(payload);
+  }
+  private toPayload(method: string, params: any[] = []) {
+    const payload = JSON.stringify({
+      id: this.id,
+      method,
+      params,
+    });
+    this.id++;
+    return payload;
+  }
+  private async sendAsync(payload: string): Promise<any> {
+    const opts = {
+      method: 'POST',
+      body: payload,
+    };
+    const response = await fetch(`http://${this.host}:${this.port}`, opts);
+    const responsePayload = await response.json();
+    return responsePayload;
+  }
+}
diff --git a/packages/contracts/util/token_registry_wrapper.ts b/packages/contracts/util/token_registry_wrapper.ts
new file mode 100644
index 000000000..5065a1802
--- /dev/null
+++ b/packages/contracts/util/token_registry_wrapper.ts
@@ -0,0 +1,56 @@
+import {ContractInstance, Token} from './types';
+
+export class TokenRegWrapper {
+  private tokenReg: ContractInstance;
+  constructor(tokenRegContractInstance: ContractInstance) {
+    this.tokenReg = tokenRegContractInstance;
+  }
+  public addTokenAsync(token: Token, from: string) {
+    const tx = this.tokenReg.addToken(
+      token.address,
+      token.name,
+      token.symbol,
+      token.decimals,
+      token.ipfsHash,
+      token.swarmHash,
+      {from},
+    );
+    return tx;
+  }
+  public async getTokenMetaDataAsync(tokenAddress: string) {
+    const data = await this.tokenReg.getTokenMetaData(tokenAddress);
+    const token: Token = {
+      address: data[0],
+      name: data[1],
+      symbol: data[2],
+      decimals: data[3].toNumber(),
+      ipfsHash: data[4],
+      swarmHash: data[5],
+    };
+    return token;
+  }
+  public async getTokenByNameAsync(tokenName: string) {
+    const data = await this.tokenReg.getTokenByName(tokenName);
+    const token: Token = {
+      address: data[0],
+      name: data[1],
+      symbol: data[2],
+      decimals: data[3].toNumber(),
+      ipfsHash: data[4],
+      swarmHash: data[5],
+    };
+    return token;
+  }
+  public async getTokenBySymbolAsync(tokenSymbol: string) {
+    const data = await this.tokenReg.getTokenBySymbol(tokenSymbol);
+    const token: Token = {
+      address: data[0],
+      name: data[1],
+      symbol: data[2],
+      decimals: data[3].toNumber(),
+      ipfsHash: data[4],
+      swarmHash: data[5],
+    };
+    return token;
+  }
+}
diff --git a/packages/contracts/util/types.ts b/packages/contracts/util/types.ts
new file mode 100644
index 000000000..2e16fac7a
--- /dev/null
+++ b/packages/contracts/util/types.ts
@@ -0,0 +1,119 @@
+import {BigNumber} from 'bignumber.js';
+import * as Web3 from 'web3';
+
+export interface BalancesByOwner {
+  [ownerAddress: string]: {
+    [tokenAddress: string]: BigNumber;
+  };
+}
+
+export interface BatchFillOrders {
+  orderAddresses: string[][];
+  orderValues: BigNumber[][];
+  fillTakerTokenAmounts: BigNumber[];
+  shouldThrowOnInsufficientBalanceOrAllowance: boolean;
+  v: number[];
+  r: string[];
+  s: string[];
+}
+
+export interface FillOrdersUpTo {
+  orderAddresses: string[][];
+  orderValues: BigNumber[][];
+  fillTakerTokenAmount: BigNumber;
+  shouldThrowOnInsufficientBalanceOrAllowance: boolean;
+  v: number[];
+  r: string[];
+  s: string[];
+}
+
+export interface BatchCancelOrders {
+  orderAddresses: string[][];
+  orderValues: BigNumber[][];
+  cancelTakerTokenAmounts: BigNumber[];
+}
+
+export interface DefaultOrderParams {
+  exchangeContractAddress: string;
+  maker: string;
+  feeRecipient: string;
+  makerToken: string;
+  takerToken: string;
+  makerTokenAmount: BigNumber;
+  takerTokenAmount: BigNumber;
+  makerFee: BigNumber;
+  takerFee: BigNumber;
+}
+
+export interface OptionalOrderParams {
+  exchangeContractAddress?: string;
+  maker?: string;
+  taker?: string;
+  feeRecipient?: string;
+  makerToken?: string;
+  takerToken?: string;
+  makerTokenAmount?: BigNumber;
+  takerTokenAmount?: BigNumber;
+  makerFee?: BigNumber;
+  takerFee?: BigNumber;
+  expirationTimestampInSec?: BigNumber;
+}
+
+export interface OrderParams {
+  exchangeContractAddress: string;
+  maker: string;
+  taker: string;
+  feeRecipient: string;
+  makerToken: string;
+  takerToken: string;
+  makerTokenAmount: BigNumber;
+  takerTokenAmount: BigNumber;
+  makerFee: BigNumber;
+  takerFee: BigNumber;
+  expirationTimestampInSec: BigNumber;
+  salt: BigNumber;
+  orderHashHex?: string;
+  v?: number;
+  r?: string;
+  s?: string;
+}
+
+export interface TransactionDataParams {
+  name: string;
+  abi: Web3.AbiDefinition[];
+  args: any[];
+}
+
+export interface Token {
+  address?: string;
+  name: string;
+  symbol: string;
+  decimals: number;
+  ipfsHash: string;
+  swarmHash: string;
+}
+
+export interface MultiSigConfig {
+  owners: string[];
+  confirmationsRequired: number;
+  secondsRequired: number;
+}
+
+export interface MultiSigConfigByNetwork {
+  [networkName: string]: MultiSigConfig;
+}
+
+export interface TokenInfoByNetwork {
+  development: Token[];
+  live: Token[];
+}
+
+// Named type aliases to improve readability
+export type ContractInstance = any;
+
+export enum ExchangeContractErrs {
+  ERROR_ORDER_EXPIRED,
+  ERROR_ORDER_FULLY_FILLED_OR_CANCELLED,
+  ERROR_ROUNDING_ERROR_TOO_LARGE,
+  ERROR_INSUFFICIENT_BALANCE_OR_ALLOWANCE,
+}