Add getExchangeInstanceOrThrowAsync && getSenderAddressOrThrowAsync

1 files changed, 7 insertions, 0 deletions

diff --git a/src/web3_wrapper.ts b/src/web3_wrapper.ts
index 3b460e4da..72daabe6f 100644
--- a/src/web3_wrapper.ts
+++ b/src/web3_wrapper.ts
@@ -2,6 +2,8 @@ import * as _ from 'lodash';
 import * as Web3 from 'web3';
 import * as BigNumber from 'bignumber.js';
 import promisify = require('es6-promisify');
+import {ZeroExError} from "./types";
+import {assert} from "./utils/assert";
 
 export class Web3Wrapper {
     private web3: Web3;
@@ -20,6 +22,11 @@ export class Web3Wrapper {
         const firstAccount = await this.getFirstAddressIfExistsAsync();
         return firstAccount;
     }
+    public async getSenderAddressOrThrowAsync(): Promise<string> {
+        const senderAddressIfExists = await this.getSenderAddressIfExistsAsync();
+        assert.assert(!_.isUndefined(senderAddressIfExists), ZeroExError.USER_HAS_NO_ASSOCIATED_ADDRESSES);
+        return senderAddressIfExists as string;
+    }
     public async getFirstAddressIfExistsAsync(): Promise<string|undefined> {
         const addresses = await promisify(this.web3.eth.getAccounts)();
         if (_.isEmpty(addresses)) {