Poll channels to keep home screen up to date

src/action/channel.js

@@ -3,7 +3,7 @@
  * call the corresponding GRPC apis for channel management.
  */
 
-import { toSatoshis } from '../helper';
+import { toSatoshis, poll } from '../helper';
 import * as log from './log';
 
 class ChannelAction {
@@ -58,7 +58,6 @@ class ChannelAction {
    */
   init() {
     this._nav.goChannels();
-    this.update();
   }
 
   /**
@@ -70,7 +69,6 @@ class ChannelAction {
   select({ item }) {
     this._store.selectedChannel = item;
     this._nav.goChannelDetail();
-    this.update();
   }
 
   /**
@@ -87,6 +85,14 @@ class ChannelAction {
     ]);
   }
 
+  /**
+   * Poll the channels in the background since there is no streaming grpc api
+   * @return {Promise<undefined>}
+   */
+  async pollChannels() {
+    await poll(() => this.update());
+  }
+
   //
   // Generic channel actions
   //

src/action/index-mobile.js

@@ -100,7 +100,7 @@ when(
     wallet.getNewAddress();
     wallet.pollBalances();
     wallet.pollExchangeRate();
-    channel.update();
+    channel.pollChannels();
     transaction.update();
     info.pollInfo();
   }

src/action/index.js

@@ -91,7 +91,7 @@ when(
     wallet.getNewAddress();
     wallet.pollBalances();
     wallet.pollExchangeRate();
-    channel.update();
+    channel.pollChannels();
     transaction.update();
     transaction.subscribeTransactions();
     transaction.subscribeInvoices();

test/unit/action/channel.spec.js

@@ -59,21 +59,17 @@ describe('Action Channels Unit Tests', () => {
   });
 
   describe('init()', () => {
-    it('should update channels and navigate to list', () => {
-      sandbox.stub(channel, 'update');
+    it('should navigate to list', () => {
       channel.init();
-      expect(channel.update, 'was called once');
       expect(nav.goChannels, 'was called once');
     });
   });
 
   describe('select()', () => {
     it('should set selectedChannel', () => {
-      sandbox.stub(channel, 'update');
       const item = 'some-channel';
       channel.select({ item });
       expect(store.selectedChannel, 'to equal', 'some-channel');
-      expect(channel.update, 'was called once');
       expect(nav.goChannelDetail, 'was called once');
     });
   });
@@ -85,6 +81,15 @@ describe('Action Channels Unit Tests', () => {
     });
   });
 
+  describe('pollChannels()', () => {
+    it('should poll all channels', async () => {
+      sandbox.stub(channel, 'update');
+      channel.update.onSecondCall().resolves(true);
+      await channel.pollChannels();
+      expect(channel.update, 'was called twice');
+    });
+  });
+
   describe('getChannels()', () => {
     it('should list open channels', async () => {
       grpc.sendCommand.withArgs('listChannels').resolves({