1 files changed, 79 insertions, 7 deletions

diff --git a/packages/0x.js/src/contract_wrappers/ether_token_wrapper.ts b/packages/0x.js/src/contract_wrappers/ether_token_wrapper.ts
index a6acbe45d..969f30463 100644
--- a/packages/0x.js/src/contract_wrappers/ether_token_wrapper.ts
+++ b/packages/0x.js/src/contract_wrappers/ether_token_wrapper.ts
@@ -1,9 +1,20 @@
+import {schemas} from '@0xproject/json-schemas';
 import {Web3Wrapper} from '@0xproject/web3-wrapper';
 import BigNumber from 'bignumber.js';
 import * as _ from 'lodash';
 
 import {artifacts} from '../artifacts';
-import {TransactionOpts, ZeroExError} from '../types';
+import {
+    BlockRange,
+    EtherTokenContractEventArgs,
+    EtherTokenEvents,
+    EventCallback,
+    IndexedFilterValues,
+    LogWithDecodedArgs,
+    TransactionOpts,
+    ZeroExError,
+} from '../types';
+import {AbiDecoder} from '../utils/abi_decoder';
 import {assert} from '../utils/assert';
 
 import {ContractWrapper} from './contract_wrapper';
@@ -15,10 +26,10 @@ import {TokenWrapper} from './token_wrapper';
  * The caller can convert ETH into the equivalent number of wrapped ETH ERC20 tokens and back.
  */
 export class EtherTokenWrapper extends ContractWrapper {
-    private _etherTokenContractIfExists?: EtherTokenContract;
+    private _etherTokenContractsByAddress: {[address: string]: EtherTokenContract} = {};
     private _tokenWrapper: TokenWrapper;
-    constructor(web3Wrapper: Web3Wrapper, networkId: number, tokenWrapper: TokenWrapper) {
-        super(web3Wrapper, networkId);
+    constructor(web3Wrapper: Web3Wrapper, networkId: number, abiDecoder: AbiDecoder, tokenWrapper: TokenWrapper) {
+        super(web3Wrapper, networkId, abiDecoder);
         this._tokenWrapper = tokenWrapper;
     }
     /**
@@ -75,15 +86,76 @@ export class EtherTokenWrapper extends ContractWrapper {
         });
         return txHash;
     }
+    /**
+     * Gets historical logs without creating a subscription
+     * @param   etherTokenAddress   An address of the ether token that emmited the logs.
+     * @param   eventName           The ether token contract event you would like to subscribe to.
+     * @param   blockRange          Block range to get logs from.
+     * @param   indexFilterValues   An object where the keys are indexed args returned by the event and
+     *                              the value is the value you are interested in. E.g `{_owner: aUserAddressHex}`
+     * @return  Array of logs that match the parameters
+     */
+    public async getLogsAsync<ArgsType extends EtherTokenContractEventArgs>(
+        etherTokenAddress: string, eventName: EtherTokenEvents, blockRange: BlockRange,
+        indexFilterValues: IndexedFilterValues): Promise<Array<LogWithDecodedArgs<ArgsType>>> {
+        assert.isETHAddressHex('etherTokenAddress', etherTokenAddress);
+        assert.doesBelongToStringEnum('eventName', eventName, EtherTokenEvents);
+        assert.doesConformToSchema('blockRange', blockRange, schemas.blockRangeSchema);
+        assert.doesConformToSchema('indexFilterValues', indexFilterValues, schemas.indexFilterValuesSchema);
+        const logs = await this._getLogsAsync<ArgsType>(
+            etherTokenAddress, eventName, blockRange, indexFilterValues, artifacts.EtherTokenArtifact.abi,
+        );
+        return logs;
+    }
+    /**
+     * Subscribe to an event type emitted by the Token contract.
+     * @param   etherTokenAddress   The hex encoded address where the ether token is deployed.
+     * @param   eventName           The ether token contract event you would like to subscribe to.
+     * @param   indexFilterValues   An object where the keys are indexed args returned by the event and
+     *                              the value is the value you are interested in. E.g `{_owner: aUserAddressHex}`
+     * @param   callback            Callback that gets called when a log is added/removed
+     * @return Subscription token used later to unsubscribe
+     */
+    public subscribe<ArgsType extends EtherTokenContractEventArgs>(
+        etherTokenAddress: string, eventName: EtherTokenEvents, indexFilterValues: IndexedFilterValues,
+        callback: EventCallback<ArgsType>): string {
+        assert.isETHAddressHex('etherTokenAddress', etherTokenAddress);
+        assert.doesBelongToStringEnum('eventName', eventName, EtherTokenEvents);
+        assert.doesConformToSchema('indexFilterValues', indexFilterValues, schemas.indexFilterValuesSchema);
+        assert.isFunction('callback', callback);
+        const subscriptionToken = this._subscribe<ArgsType>(
+            etherTokenAddress, eventName, indexFilterValues, artifacts.EtherTokenArtifact.abi, callback,
+        );
+        return subscriptionToken;
+    }
+    /**
+     * Cancel a subscription
+     * @param   subscriptionToken Subscription token returned by `subscribe()`
+     */
+    public unsubscribe(subscriptionToken: string): void {
+        this._unsubscribe(subscriptionToken);
+    }
+    /**
+     * Cancels all existing subscriptions
+     */
+    public unsubscribeAll(): void {
+        super.unsubscribeAll();
+    }
     private _invalidateContractInstance(): void {
-        delete this._etherTokenContractIfExists;
+        this.unsubscribeAll();
+        this._etherTokenContractsByAddress = {};
     }
     private async _getEtherTokenContractAsync(etherTokenAddress: string): Promise<EtherTokenContract> {
+        let etherTokenContract = this._etherTokenContractsByAddress[etherTokenAddress];
+        if (!_.isUndefined(etherTokenContract)) {
+            return etherTokenContract;
+        }
         const web3ContractInstance = await this._instantiateContractIfExistsAsync(
             artifacts.EtherTokenArtifact, etherTokenAddress,
         );
         const contractInstance = new EtherTokenContract(web3ContractInstance, this._web3Wrapper.getContractDefaults());
-        this._etherTokenContractIfExists = contractInstance;
-        return this._etherTokenContractIfExists;
+        etherTokenContract = contractInstance;
+        this._etherTokenContractsByAddress[etherTokenAddress] = etherTokenContract;
+        return etherTokenContract;
     }
 }