Merge branch 'development' of github.com:0xProject/0x.js into development

2 files changed, 14 insertions, 1 deletions

diff --git a/packages/0x.js/src/contract_wrappers/contract_wrapper.ts b/packages/0x.js/src/contract_wrappers/contract_wrapper.ts
index dcd59059f..2fbf8c32d 100644
--- a/packages/0x.js/src/contract_wrappers/contract_wrapper.ts
+++ b/packages/0x.js/src/contract_wrappers/contract_wrapper.ts
@@ -32,7 +32,7 @@ const CONTRACT_NAME_TO_NOT_FOUND_ERROR: {
 
 export class ContractWrapper {
     protected _web3Wrapper: Web3Wrapper;
-    private _networkId: number;
+    protected _networkId: number;
     private _abiDecoder?: AbiDecoder;
     private _blockAndLogStreamerIfExists?: BlockAndLogStreamer;
     private _blockAndLogStreamIntervalIfExists?: NodeJS.Timer;
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 cbafcfe94..32c9ae6a9 100644
--- a/packages/0x.js/src/contract_wrappers/ether_token_wrapper.ts
+++ b/packages/0x.js/src/contract_wrappers/ether_token_wrapper.ts
@@ -162,6 +162,19 @@ export class EtherTokenWrapper extends ContractWrapper {
     public _unsubscribeAll(): void {
         super._unsubscribeAll();
     }
+    /**
+     * Retrieves the Ethereum address of the EtherToken contract deployed on the network
+     * that the user-passed web3 provider is connected to. If it's not Kovan, Ropsten, Rinkeby, Mainnet or TestRPC
+     * (networkId: 50), it will return undefined (e.g a private network).
+     * @returns The Ethereum address of the EtherToken contract or undefined.
+     */
+    public getContractAddressIfExists(): string | undefined {
+        const networkSpecificArtifact = artifacts.EtherTokenArtifact.networks[this._networkId];
+        const contractAddressIfExists = _.isUndefined(networkSpecificArtifact)
+            ? undefined
+            : networkSpecificArtifact.address;
+        return contractAddressIfExists;
+    }
     private _invalidateContractInstance(): void {
         this._unsubscribeAll();
         this._etherTokenContractsByAddress = {};