Merge pull request #797 from 0xProject/refactor/contracts/registerAssetProxy

Make registerAssetProxy append only

12 files changed, 68 insertions, 203 deletions

diff --git a/packages/contracts/src/contracts/current/protocol/Exchange/MixinAssetProxyDispatcher.sol b/packages/contracts/src/contracts/current/protocol/Exchange/MixinAssetProxyDispatcher.sol
index 520569185..9e9d88ce7 100644
--- a/packages/contracts/src/contracts/current/protocol/Exchange/MixinAssetProxyDispatcher.sol
+++ b/packages/contracts/src/contracts/current/protocol/Exchange/MixinAssetProxyDispatcher.sol
@@ -32,43 +32,28 @@ contract MixinAssetProxyDispatcher is
     // Mapping from Asset Proxy Id's to their respective Asset Proxy
     mapping (bytes4 => IAssetProxy) public assetProxies;
 
-    /// @dev Registers an asset proxy to an asset proxy id.
-    ///      An id can only be assigned to a single proxy at a given time.
-    /// @param assetProxyId Id to register`newAssetProxy` under.
-    /// @param newAssetProxy Address of new asset proxy to register, or 0x0 to unset assetProxyId.
-    /// @param oldAssetProxy Existing asset proxy to overwrite, or 0x0 if assetProxyId is currently unused.
-    function registerAssetProxy(
-        bytes4 assetProxyId,
-        address newAssetProxy,
-        address oldAssetProxy
-    )
+    /// @dev Registers an asset proxy to its asset proxy id.
+    ///      Once an asset proxy is registered, it cannot be unregistered.
+    /// @param assetProxy Address of new asset proxy to register.
+    function registerAssetProxy(address assetProxy)
         external
         onlyOwner
     {
-        // Ensure the existing asset proxy is not unintentionally overwritten
+        IAssetProxy assetProxyContract = IAssetProxy(assetProxy);
+
+        // Ensure that no asset proxy exists with current id.
+        bytes4 assetProxyId = assetProxyContract.getProxyId();
         address currentAssetProxy = assetProxies[assetProxyId];
         require(
-            oldAssetProxy == currentAssetProxy,
-            "ASSET_PROXY_MISMATCH"
+            currentAssetProxy == address(0),
+            "ASSET_PROXY_ALREADY_EXISTS"
         );
 
-        IAssetProxy assetProxy = IAssetProxy(newAssetProxy);
-
-        // Ensure that the id of newAssetProxy matches the passed in assetProxyId, unless it is being reset to 0.
-        if (newAssetProxy != address(0)) {
-            bytes4 newAssetProxyId = assetProxy.getProxyId();
-            require(
-                newAssetProxyId == assetProxyId,
-                "ASSET_PROXY_ID_MISMATCH"
-            );
-        }
-
         // Add asset proxy and log registration.
-        assetProxies[assetProxyId] = assetProxy;
-        emit AssetProxySet(
+        assetProxies[assetProxyId] = assetProxyContract;
+        emit AssetProxyRegistered(
             assetProxyId,
-            newAssetProxy,
-            oldAssetProxy
+            assetProxy
         );
     }
 
@@ -112,7 +97,7 @@ contract MixinAssetProxyDispatcher is
                     0xFFFFFFFF00000000000000000000000000000000000000000000000000000000
                 )
             }
-            IAssetProxy assetProxy = assetProxies[assetProxyId];
+            address assetProxy = assetProxies[assetProxyId];
 
             // Ensure that assetProxy exists
             require(
diff --git a/packages/contracts/src/contracts/current/protocol/Exchange/interfaces/IAssetProxyDispatcher.sol b/packages/contracts/src/contracts/current/protocol/Exchange/interfaces/IAssetProxyDispatcher.sol
index fa55dff00..66f3b5796 100644
--- a/packages/contracts/src/contracts/current/protocol/Exchange/interfaces/IAssetProxyDispatcher.sol
+++ b/packages/contracts/src/contracts/current/protocol/Exchange/interfaces/IAssetProxyDispatcher.sol
@@ -20,16 +20,10 @@ pragma solidity ^0.4.24;
 
 contract IAssetProxyDispatcher {
 
-    /// @dev Registers an asset proxy to an asset proxy id.
-    ///      An id can only be assigned to a single proxy at a given time.
-    /// @param assetProxyId Id to register`newAssetProxy` under.
-    /// @param newAssetProxy Address of new asset proxy to register, or 0x0 to unset assetProxyId.
-    /// @param oldAssetProxy Existing asset proxy to overwrite, or 0x0 if assetProxyId is currently unused.
-    function registerAssetProxy(
-        bytes4 assetProxyId,
-        address newAssetProxy,
-        address oldAssetProxy
-    )
+    /// @dev Registers an asset proxy to its asset proxy id.
+    ///      Once an asset proxy is registered, it cannot be unregistered.
+    /// @param assetProxy Address of new asset proxy to register.
+    function registerAssetProxy(address assetProxy)
         external;
 
     /// @dev Gets an asset proxy.
diff --git a/packages/contracts/src/contracts/current/protocol/Exchange/libs/LibExchangeErrors.sol b/packages/contracts/src/contracts/current/protocol/Exchange/libs/LibExchangeErrors.sol
index e37f41ada..01aa78a1d 100644
--- a/packages/contracts/src/contracts/current/protocol/Exchange/libs/LibExchangeErrors.sol
+++ b/packages/contracts/src/contracts/current/protocol/Exchange/libs/LibExchangeErrors.sol
@@ -54,8 +54,7 @@ contract LibExchangeErrors {
     string constant FAILED_EXECUTION = "FAILED_EXECUTION";                              // Transaction execution failed. 
     
     /// registerAssetProxy errors ///
-    string constant ASSET_PROXY_MISMATCH = "ASSET_PROXY_MISMATCH";                      // oldAssetProxy proxy does not match currentAssetProxy. 
-    string constant ASSET_PROXY_ID_MISMATCH = "ASSET_PROXY_ID_MISMATCH";                // newAssetProxyId does not match given assetProxyId.
+    string constant ASSET_PROXY_ALREADY_EXISTS = "ASSET_PROXY_ALREADY_EXISTS";          // AssetProxy with same id already exists.
 
     /// dispatchTransferFrom errors ///
     string constant ASSET_PROXY_DOES_NOT_EXIST = "ASSET_PROXY_DOES_NOT_EXIST";          // No assetProxy registered at given id.
diff --git a/packages/contracts/src/contracts/current/protocol/Exchange/mixins/MAssetProxyDispatcher.sol b/packages/contracts/src/contracts/current/protocol/Exchange/mixins/MAssetProxyDispatcher.sol
index c2b506dcf..5bf59c6ce 100644
--- a/packages/contracts/src/contracts/current/protocol/Exchange/mixins/MAssetProxyDispatcher.sol
+++ b/packages/contracts/src/contracts/current/protocol/Exchange/mixins/MAssetProxyDispatcher.sol
@@ -26,10 +26,9 @@ contract MAssetProxyDispatcher is
 {
 
     // Logs registration of new asset proxy
-    event AssetProxySet(
+    event AssetProxyRegistered(
         bytes4 id,              // Id of new registered AssetProxy.
-        address newAssetProxy,  // Address of new registered AssetProxy.
-        address oldAssetProxy   // Address of AssetProxy that was overwritten at given id (or null address).
+        address assetProxy      // Address of new registered AssetProxy.
     );
 
     /// @dev Forwards arguments to assetProxy and calls `transferFrom`. Either succeeds or throws.
diff --git a/packages/contracts/src/utils/core_combinatorial_utils.ts b/packages/contracts/src/utils/core_combinatorial_utils.ts
index 5b725fbe3..93f4fc79d 100644
--- a/packages/contracts/src/utils/core_combinatorial_utils.ts
+++ b/packages/contracts/src/utils/core_combinatorial_utils.ts
@@ -96,8 +96,8 @@ export async function coreCombinatorialUtilsFactoryAsync(
         zrxAssetData,
     );
     const exchangeWrapper = new ExchangeWrapper(exchangeContract, provider);
-    await exchangeWrapper.registerAssetProxyAsync(AssetProxyId.ERC20, erc20Proxy.address, ownerAddress);
-    await exchangeWrapper.registerAssetProxyAsync(AssetProxyId.ERC721, erc721Proxy.address, ownerAddress);
+    await exchangeWrapper.registerAssetProxyAsync(erc20Proxy.address, ownerAddress);
+    await exchangeWrapper.registerAssetProxyAsync(erc721Proxy.address, ownerAddress);
 
     await web3Wrapper.awaitTransactionSuccessAsync(
         await erc20Proxy.addAuthorizedAddress.sendTransactionAsync(exchangeContract.address, {
diff --git a/packages/contracts/src/utils/exchange_wrapper.ts b/packages/contracts/src/utils/exchange_wrapper.ts
index ad68c8ff4..baf967065 100644
--- a/packages/contracts/src/utils/exchange_wrapper.ts
+++ b/packages/contracts/src/utils/exchange_wrapper.ts
@@ -1,12 +1,10 @@
-import { AssetProxyId, SignedOrder } from '@0xproject/types';
+import { SignedOrder } from '@0xproject/types';
 import { BigNumber } from '@0xproject/utils';
 import { Web3Wrapper } from '@0xproject/web3-wrapper';
 import { Provider, TransactionReceiptWithDecodedLogs } from 'ethereum-types';
-import * as _ from 'lodash';
 
 import { ExchangeContract } from '../generated_contract_wrappers/exchange';
 
-import { constants } from './constants';
 import { formatters } from './formatters';
 import { LogDecoder } from './log_decoder';
 import { orderUtils } from './order_utils';
@@ -192,20 +190,10 @@ export class ExchangeWrapper {
         return tx;
     }
     public async registerAssetProxyAsync(
-        assetProxyId: AssetProxyId,
         assetProxyAddress: string,
         from: string,
-        opts: { oldAssetProxyAddressIfExists?: string } = {},
     ): Promise<TransactionReceiptWithDecodedLogs> {
-        const oldAssetProxyAddress = _.isUndefined(opts.oldAssetProxyAddressIfExists)
-            ? constants.NULL_ADDRESS
-            : opts.oldAssetProxyAddressIfExists;
-        const txHash = await this._exchange.registerAssetProxy.sendTransactionAsync(
-            assetProxyId,
-            assetProxyAddress,
-            oldAssetProxyAddress,
-            { from },
-        );
+        const txHash = await this._exchange.registerAssetProxy.sendTransactionAsync(assetProxyAddress, { from });
         const tx = await this._logDecoder.getTxWithDecodedLogsAsync(txHash);
         return tx;
     }
diff --git a/packages/contracts/test/exchange/core.ts b/packages/contracts/test/exchange/core.ts
index 0c7381aac..682de01c2 100644
--- a/packages/contracts/test/exchange/core.ts
+++ b/packages/contracts/test/exchange/core.ts
@@ -1,6 +1,6 @@
 import { BlockchainLifecycle } from '@0xproject/dev-utils';
 import { assetProxyUtils, orderHashUtils } from '@0xproject/order-utils';
-import { AssetProxyId, RevertReason, SignedOrder } from '@0xproject/types';
+import { RevertReason, SignedOrder } from '@0xproject/types';
 import { BigNumber } from '@0xproject/utils';
 import { Web3Wrapper } from '@0xproject/web3-wrapper';
 import * as chai from 'chai';
@@ -90,8 +90,8 @@ describe('Exchange core', () => {
             assetProxyUtils.encodeERC20AssetData(zrxToken.address),
         );
         exchangeWrapper = new ExchangeWrapper(exchange, provider);
-        await exchangeWrapper.registerAssetProxyAsync(AssetProxyId.ERC20, erc20Proxy.address, owner);
-        await exchangeWrapper.registerAssetProxyAsync(AssetProxyId.ERC721, erc721Proxy.address, owner);
+        await exchangeWrapper.registerAssetProxyAsync(erc20Proxy.address, owner);
+        await exchangeWrapper.registerAssetProxyAsync(erc721Proxy.address, owner);
 
         await web3Wrapper.awaitTransactionSuccessAsync(
             await erc20Proxy.addAuthorizedAddress.sendTransactionAsync(exchange.address, {
diff --git a/packages/contracts/test/exchange/dispatcher.ts b/packages/contracts/test/exchange/dispatcher.ts
index e35cca845..8c1052922 100644
--- a/packages/contracts/test/exchange/dispatcher.ts
+++ b/packages/contracts/test/exchange/dispatcher.ts
@@ -3,24 +3,29 @@ import { assetProxyUtils } from '@0xproject/order-utils';
 import { AssetProxyId, RevertReason } from '@0xproject/types';
 import { BigNumber } from '@0xproject/utils';
 import * as chai from 'chai';
+import { LogWithDecodedArgs } from 'ethereum-types';
 import * as _ from 'lodash';
 
 import { DummyERC20TokenContract } from '../../src/generated_contract_wrappers/dummy_e_r_c20_token';
 import { ERC20ProxyContract } from '../../src/generated_contract_wrappers/e_r_c20_proxy';
 import { ERC721ProxyContract } from '../../src/generated_contract_wrappers/e_r_c721_proxy';
-import { TestAssetProxyDispatcherContract } from '../../src/generated_contract_wrappers/test_asset_proxy_dispatcher';
+import {
+    AssetProxyRegisteredContractEventArgs,
+    TestAssetProxyDispatcherContract,
+} from '../../src/generated_contract_wrappers/test_asset_proxy_dispatcher';
 import { artifacts } from '../../src/utils/artifacts';
 import { expectRevertReasonOrAlwaysFailingTransactionAsync } from '../../src/utils/assertions';
 import { chaiSetup } from '../../src/utils/chai_setup';
 import { constants } from '../../src/utils/constants';
 import { ERC20Wrapper } from '../../src/utils/erc20_wrapper';
 import { ERC721Wrapper } from '../../src/utils/erc721_wrapper';
+import { LogDecoder } from '../../src/utils/log_decoder';
 import { provider, txDefaults, web3Wrapper } from '../../src/utils/web3_wrapper';
 
 chaiSetup.configure();
 const expect = chai.expect;
 const blockchainLifecycle = new BlockchainLifecycle(web3Wrapper);
-
+// tslint:disable:no-unnecessary-type-assertion
 describe('AssetProxyDispatcher', () => {
     let owner: string;
     let notOwner: string;
@@ -82,14 +87,8 @@ describe('AssetProxyDispatcher', () => {
     });
     describe('registerAssetProxy', () => {
         it('should record proxy upon registration', async () => {
-            const prevProxyAddress = constants.NULL_ADDRESS;
             await web3Wrapper.awaitTransactionSuccessAsync(
-                await assetProxyDispatcher.registerAssetProxy.sendTransactionAsync(
-                    AssetProxyId.ERC20,
-                    erc20Proxy.address,
-                    prevProxyAddress,
-                    { from: owner },
-                ),
+                await assetProxyDispatcher.registerAssetProxy.sendTransactionAsync(erc20Proxy.address, { from: owner }),
                 constants.AWAIT_TRANSACTION_MINED_MS,
             );
             const proxyAddress = await assetProxyDispatcher.getAssetProxy.callAsync(AssetProxyId.ERC20);
@@ -98,46 +97,30 @@ describe('AssetProxyDispatcher', () => {
 
         it('should be able to record multiple proxies', async () => {
             // Record first proxy
-            const prevERC20ProxyAddress = constants.NULL_ADDRESS;
             await web3Wrapper.awaitTransactionSuccessAsync(
-                await assetProxyDispatcher.registerAssetProxy.sendTransactionAsync(
-                    AssetProxyId.ERC20,
-                    erc20Proxy.address,
-                    prevERC20ProxyAddress,
-                    { from: owner },
-                ),
+                await assetProxyDispatcher.registerAssetProxy.sendTransactionAsync(erc20Proxy.address, { from: owner }),
                 constants.AWAIT_TRANSACTION_MINED_MS,
             );
             let proxyAddress = await assetProxyDispatcher.getAssetProxy.callAsync(AssetProxyId.ERC20);
             expect(proxyAddress).to.be.equal(erc20Proxy.address);
             // Record another proxy
-            const prevERC721ProxyAddress = constants.NULL_ADDRESS;
             await web3Wrapper.awaitTransactionSuccessAsync(
-                await assetProxyDispatcher.registerAssetProxy.sendTransactionAsync(
-                    AssetProxyId.ERC721,
-                    erc721Proxy.address,
-                    prevERC721ProxyAddress,
-                    { from: owner },
-                ),
+                await assetProxyDispatcher.registerAssetProxy.sendTransactionAsync(erc721Proxy.address, {
+                    from: owner,
+                }),
                 constants.AWAIT_TRANSACTION_MINED_MS,
             );
             proxyAddress = await assetProxyDispatcher.getAssetProxy.callAsync(AssetProxyId.ERC721);
             expect(proxyAddress).to.be.equal(erc721Proxy.address);
         });
 
-        it('should replace proxy address upon re-registration', async () => {
+        it('should throw if a proxy with the same id is already registered', async () => {
             // Initial registration
-            const prevProxyAddress = constants.NULL_ADDRESS;
             await web3Wrapper.awaitTransactionSuccessAsync(
-                await assetProxyDispatcher.registerAssetProxy.sendTransactionAsync(
-                    AssetProxyId.ERC20,
-                    erc20Proxy.address,
-                    prevProxyAddress,
-                    { from: owner },
-                ),
+                await assetProxyDispatcher.registerAssetProxy.sendTransactionAsync(erc20Proxy.address, { from: owner }),
                 constants.AWAIT_TRANSACTION_MINED_MS,
             );
-            let proxyAddress = await assetProxyDispatcher.getAssetProxy.callAsync(AssetProxyId.ERC20);
+            const proxyAddress = await assetProxyDispatcher.getAssetProxy.callAsync(AssetProxyId.ERC20);
             expect(proxyAddress).to.be.equal(erc20Proxy.address);
             // Deploy a new version of the ERC20 Transfer Proxy contract
             const newErc20TransferProxy = await ERC20ProxyContract.deployFrom0xArtifactAsync(
@@ -146,114 +129,37 @@ describe('AssetProxyDispatcher', () => {
                 txDefaults,
             );
             // Register new ERC20 Transfer Proxy contract
-            const newAddress = newErc20TransferProxy.address;
-            const currentAddress = erc20Proxy.address;
-            await web3Wrapper.awaitTransactionSuccessAsync(
-                await assetProxyDispatcher.registerAssetProxy.sendTransactionAsync(
-                    AssetProxyId.ERC20,
-                    newAddress,
-                    currentAddress,
-                    { from: owner },
-                ),
-                constants.AWAIT_TRANSACTION_MINED_MS,
-            );
-            // Verify new asset proxy has replaced initial version
-            proxyAddress = await assetProxyDispatcher.getAssetProxy.callAsync(AssetProxyId.ERC20);
-            expect(proxyAddress).to.be.equal(newAddress);
-        });
-
-        it('should throw if registering with incorrect "currentAssetProxyAddress" field', async () => {
-            // Initial registration
-            const prevProxyAddress = constants.NULL_ADDRESS;
-            await web3Wrapper.awaitTransactionSuccessAsync(
-                await assetProxyDispatcher.registerAssetProxy.sendTransactionAsync(
-                    AssetProxyId.ERC20,
-                    erc20Proxy.address,
-                    prevProxyAddress,
-                    { from: owner },
-                ),
-                constants.AWAIT_TRANSACTION_MINED_MS,
-            );
-            const proxyAddress = await assetProxyDispatcher.getAssetProxy.callAsync(AssetProxyId.ERC20);
-            expect(proxyAddress).to.be.equal(erc20Proxy.address);
-            // The following transaction will throw because the currentAddress is no longer constants.NULL_ADDRESS
             return expectRevertReasonOrAlwaysFailingTransactionAsync(
-                assetProxyDispatcher.registerAssetProxy.sendTransactionAsync(
-                    AssetProxyId.ERC20,
-                    erc20Proxy.address,
-                    constants.NULL_ADDRESS,
-                    { from: owner },
-                ),
-                RevertReason.AssetProxyMismatch,
+                assetProxyDispatcher.registerAssetProxy.sendTransactionAsync(newErc20TransferProxy.address, {
+                    from: owner,
+                }),
+                RevertReason.AssetProxyAlreadyExists,
             );
         });
 
-        it('should be able to reset proxy address to NULL', async () => {
-            // Initial registration
-            const prevProxyAddress = constants.NULL_ADDRESS;
-            await web3Wrapper.awaitTransactionSuccessAsync(
-                await assetProxyDispatcher.registerAssetProxy.sendTransactionAsync(
-                    AssetProxyId.ERC20,
-                    erc20Proxy.address,
-                    prevProxyAddress,
-                    { from: owner },
-                ),
-                constants.AWAIT_TRANSACTION_MINED_MS,
-            );
-            const proxyAddress = await assetProxyDispatcher.getAssetProxy.callAsync(AssetProxyId.ERC20);
-            expect(proxyAddress).to.be.equal(erc20Proxy.address);
-            // The following transaction will reset the proxy address
-            const newProxyAddress = constants.NULL_ADDRESS;
-            await web3Wrapper.awaitTransactionSuccessAsync(
-                await assetProxyDispatcher.registerAssetProxy.sendTransactionAsync(
-                    AssetProxyId.ERC20,
-                    newProxyAddress,
-                    erc20Proxy.address,
-                    { from: owner },
-                ),
-                constants.AWAIT_TRANSACTION_MINED_MS,
-            );
-            const finalProxyAddress = await assetProxyDispatcher.getAssetProxy.callAsync(AssetProxyId.ERC20);
-            expect(finalProxyAddress).to.be.equal(newProxyAddress);
-        });
-
         it('should throw if requesting address is not owner', async () => {
-            const prevProxyAddress = constants.NULL_ADDRESS;
             return expectRevertReasonOrAlwaysFailingTransactionAsync(
-                assetProxyDispatcher.registerAssetProxy.sendTransactionAsync(
-                    AssetProxyId.ERC20,
-                    erc20Proxy.address,
-                    prevProxyAddress,
-                    { from: notOwner },
-                ),
+                assetProxyDispatcher.registerAssetProxy.sendTransactionAsync(erc20Proxy.address, { from: notOwner }),
                 RevertReason.OnlyContractOwner,
             );
         });
 
-        it('should throw if attempting to register a proxy to the incorrect id', async () => {
-            const prevProxyAddress = constants.NULL_ADDRESS;
-            return expectRevertReasonOrAlwaysFailingTransactionAsync(
-                assetProxyDispatcher.registerAssetProxy.sendTransactionAsync(
-                    AssetProxyId.ERC721,
-                    erc20Proxy.address,
-                    prevProxyAddress,
-                    { from: owner },
-                ),
-                RevertReason.AssetProxyIdMismatch,
+        it('should log an event with correct arguments when an asset proxy is registered', async () => {
+            const logDecoder = new LogDecoder(web3Wrapper, assetProxyDispatcher.address);
+            const txReceipt = await logDecoder.getTxWithDecodedLogsAsync(
+                await assetProxyDispatcher.registerAssetProxy.sendTransactionAsync(erc20Proxy.address, { from: owner }),
             );
+            const logs = txReceipt.logs;
+            const log = logs[0] as LogWithDecodedArgs<AssetProxyRegisteredContractEventArgs>;
+            expect(log.args.id).to.equal(AssetProxyId.ERC20);
+            expect(log.args.assetProxy).to.equal(erc20Proxy.address);
         });
     });
 
     describe('getAssetProxy', () => {
         it('should return correct address of registered proxy', async () => {
-            const prevProxyAddress = constants.NULL_ADDRESS;
             await web3Wrapper.awaitTransactionSuccessAsync(
-                await assetProxyDispatcher.registerAssetProxy.sendTransactionAsync(
-                    AssetProxyId.ERC20,
-                    erc20Proxy.address,
-                    prevProxyAddress,
-                    { from: owner },
-                ),
+                await assetProxyDispatcher.registerAssetProxy.sendTransactionAsync(erc20Proxy.address, { from: owner }),
                 constants.AWAIT_TRANSACTION_MINED_MS,
             );
             const proxyAddress = await assetProxyDispatcher.getAssetProxy.callAsync(AssetProxyId.ERC20);
@@ -269,14 +175,8 @@ describe('AssetProxyDispatcher', () => {
     describe('dispatchTransferFrom', () => {
         it('should dispatch transfer to registered proxy', async () => {
             // Register ERC20 proxy
-            const prevProxyAddress = constants.NULL_ADDRESS;
             await web3Wrapper.awaitTransactionSuccessAsync(
-                await assetProxyDispatcher.registerAssetProxy.sendTransactionAsync(
-                    AssetProxyId.ERC20,
-                    erc20Proxy.address,
-                    prevProxyAddress,
-                    { from: owner },
-                ),
+                await assetProxyDispatcher.registerAssetProxy.sendTransactionAsync(erc20Proxy.address, { from: owner }),
                 constants.AWAIT_TRANSACTION_MINED_MS,
             );
             // Construct metadata for ERC20 proxy
@@ -323,3 +223,4 @@ describe('AssetProxyDispatcher', () => {
         });
     });
 });
+// tslint:enable:no-unnecessary-type-assertion
diff --git a/packages/contracts/test/exchange/match_orders.ts b/packages/contracts/test/exchange/match_orders.ts
index 7bdb9c385..3ebe7e690 100644
--- a/packages/contracts/test/exchange/match_orders.ts
+++ b/packages/contracts/test/exchange/match_orders.ts
@@ -1,6 +1,6 @@
 import { BlockchainLifecycle } from '@0xproject/dev-utils';
 import { assetProxyUtils } from '@0xproject/order-utils';
-import { AssetProxyId, RevertReason } from '@0xproject/types';
+import { RevertReason } from '@0xproject/types';
 import { BigNumber } from '@0xproject/utils';
 import { Web3Wrapper } from '@0xproject/web3-wrapper';
 import * as chai from 'chai';
@@ -103,8 +103,8 @@ describe('matchOrders', () => {
             assetProxyUtils.encodeERC20AssetData(zrxToken.address),
         );
         exchangeWrapper = new ExchangeWrapper(exchange, provider);
-        await exchangeWrapper.registerAssetProxyAsync(AssetProxyId.ERC20, erc20Proxy.address, owner);
-        await exchangeWrapper.registerAssetProxyAsync(AssetProxyId.ERC721, erc721Proxy.address, owner);
+        await exchangeWrapper.registerAssetProxyAsync(erc20Proxy.address, owner);
+        await exchangeWrapper.registerAssetProxyAsync(erc721Proxy.address, owner);
         // Authorize ERC20 and ERC721 trades by exchange
         await web3Wrapper.awaitTransactionSuccessAsync(
             await erc20Proxy.addAuthorizedAddress.sendTransactionAsync(exchange.address, {
diff --git a/packages/contracts/test/exchange/transactions.ts b/packages/contracts/test/exchange/transactions.ts
index c4de58bb9..23441e7f8 100644
--- a/packages/contracts/test/exchange/transactions.ts
+++ b/packages/contracts/test/exchange/transactions.ts
@@ -1,6 +1,6 @@
 import { BlockchainLifecycle } from '@0xproject/dev-utils';
 import { assetProxyUtils, generatePseudoRandomSalt } from '@0xproject/order-utils';
-import { AssetProxyId, OrderWithoutExchangeAddress, RevertReason, SignedOrder } from '@0xproject/types';
+import { OrderWithoutExchangeAddress, RevertReason, SignedOrder } from '@0xproject/types';
 import { BigNumber } from '@0xproject/utils';
 import * as chai from 'chai';
 import * as _ from 'lodash';
@@ -91,7 +91,7 @@ describe('Exchange transactions', () => {
             assetProxyUtils.encodeERC20AssetData(zrxToken.address),
         );
         exchangeWrapper = new ExchangeWrapper(exchange, provider);
-        await exchangeWrapper.registerAssetProxyAsync(AssetProxyId.ERC20, erc20Proxy.address, owner);
+        await exchangeWrapper.registerAssetProxyAsync(erc20Proxy.address, owner);
 
         await web3Wrapper.awaitTransactionSuccessAsync(
             await erc20Proxy.addAuthorizedAddress.sendTransactionAsync(exchange.address, { from: owner }),
diff --git a/packages/contracts/test/exchange/wrapper.ts b/packages/contracts/test/exchange/wrapper.ts
index 1af8bde9d..6abb660a8 100644
--- a/packages/contracts/test/exchange/wrapper.ts
+++ b/packages/contracts/test/exchange/wrapper.ts
@@ -1,6 +1,6 @@
 import { BlockchainLifecycle } from '@0xproject/dev-utils';
 import { assetProxyUtils } from '@0xproject/order-utils';
-import { AssetProxyId, RevertReason, SignedOrder } from '@0xproject/types';
+import { RevertReason, SignedOrder } from '@0xproject/types';
 import { BigNumber } from '@0xproject/utils';
 import { Web3Wrapper } from '@0xproject/web3-wrapper';
 import * as chai from 'chai';
@@ -87,8 +87,8 @@ describe('Exchange wrappers', () => {
             assetProxyUtils.encodeERC20AssetData(zrxToken.address),
         );
         exchangeWrapper = new ExchangeWrapper(exchange, provider);
-        await exchangeWrapper.registerAssetProxyAsync(AssetProxyId.ERC20, erc20Proxy.address, owner);
-        await exchangeWrapper.registerAssetProxyAsync(AssetProxyId.ERC721, erc721Proxy.address, owner);
+        await exchangeWrapper.registerAssetProxyAsync(erc20Proxy.address, owner);
+        await exchangeWrapper.registerAssetProxyAsync(erc721Proxy.address, owner);
 
         await web3Wrapper.awaitTransactionSuccessAsync(
             await erc20Proxy.addAuthorizedAddress.sendTransactionAsync(exchange.address, {
diff --git a/packages/types/src/index.ts b/packages/types/src/index.ts
index 4b70c36f9..4ad10fdee 100644
--- a/packages/types/src/index.ts
+++ b/packages/types/src/index.ts
@@ -187,8 +187,7 @@ export enum RevertReason {
     InvalidTxHash = 'INVALID_TX_HASH',
     InvalidTxSignature = 'INVALID_TX_SIGNATURE',
     FailedExecution = 'FAILED_EXECUTION',
-    AssetProxyMismatch = 'ASSET_PROXY_MISMATCH',
-    AssetProxyIdMismatch = 'ASSET_PROXY_ID_MISMATCH',
+    AssetProxyAlreadyExists = 'ASSET_PROXY_ALREADY_EXISTS',
     LengthGreaterThan0Required = 'LENGTH_GREATER_THAN_0_REQUIRED',
     LengthGreaterThan131Required = 'LENGTH_GREATER_THAN_131_REQUIRED',
     Length0Required = 'LENGTH_0_REQUIRED',