create ensureOkResponse and check against RPC responses

common/libs/nodes/rpc/index.ts

@@ -6,6 +6,21 @@ import { INode } from '../INode';
 import RPCClient from './client';
 import RPCRequests from './requests';
 
+// TODO - understand response values
+// "RPC" requests will sometimes resolve with 200, but contain a payload informing there was an error.
+function ensureOkResponse(response: any) {
+  if (response.error) {
+    throw new Error(response.error.message);
+  }
+  if (response.status === 0) {
+    throw new Error('Error!: Status Code: RSP0');
+  }
+  if (response.result.toLowerCase().includes('error')) {
+    throw new Error('Error! Status Code: "RPCLIE"');
+  }
+  return response;
+}
+
 export default class RpcNode implements INode {
   public client: RPCClient;
   public requests: RPCRequests;
@@ -18,36 +33,39 @@ export default class RpcNode implements INode {
   public getBalance(address: string): Promise<Wei> {
     return this.client
       .call(this.requests.getBalance(address))
+      .then(ensureOkResponse)
       .then(response => {
-        if (response.error) {
-          throw new Error(response.error.message);
-        }
         return new Wei(String(response.result));
+      })
+      .catch(err => {
+        throw new Error('Warning: Unable to Get Balance');
       });
   }
 
   public estimateGas(transaction: TransactionWithoutGas): Promise<BigNumber> {
     return this.client
       .call(this.requests.estimateGas(transaction))
+      .then(ensureOkResponse)
       .then(response => {
-        if (response.error) {
-          throw new Error(response.error.message);
-        }
         return new Big(String(response.result));
+      })
+      .catch(err => {
+        throw new Error('Warning: Unable to Estimate Gas');
       });
   }
 
   public getTokenBalance(address: string, token: Token): Promise<BigNumber> {
     return this.client
       .call(this.requests.getTokenBalance(address, token))
+      .then(ensureOkResponse)
       .then(response => {
-        if (response.error) {
-          // TODO - Error handling
-          return new Big(0);
-        }
         return new Big(String(response.result)).div(
           new Big(10).pow(token.decimal)
         );
+      })
+      .catch(err => {
+        // TODO - do we want to alert if a single token request fails?
+        throw new Error('Warning: Unable to Get Token Balance');
       });
   }
 
@@ -74,22 +92,30 @@ export default class RpcNode implements INode {
   public getTransactionCount(address: string): Promise<string> {
     return this.client
       .call(this.requests.getTransactionCount(address))
+      .then(ensureOkResponse)
       .then(response => {
         if (response.error) {
           throw new Error(response.error.message);
         }
         return response.result;
+      })
+      .catch(err => {
+        throw new Error('Warning: Unable to Get Transaction Count (Nonce)');
       });
   }
 
   public sendRawTx(signedTx: string): Promise<string> {
     return this.client
       .call(this.requests.sendRawTx(signedTx))
+      .then(ensureOkResponse)
       .then(response => {
         if (response.error) {
           throw new Error(response.error.message);
         }
         return response.result;
+      })
+      .catch(err => {
+        throw new Error('Warning: Unable Send Raw Tx');
       });
   }
 }