Merge pull request #1031 from lightninglabs/fee-estimation

Fee estimation

Author: tanx

src/action/payment.js

@@ -192,6 +192,25 @@ class PaymentAction {
     }
   }
 
+  /**
+   * Initialize the pay bitcoin confirm view by getting a fee estimate
+   * from lnd and navigating to the view.
+   */
+  async initPayBitcoinConfirm() {
+    try {
+      const { payment, settings } = this._store;
+      const AddrToAmount = {};
+      AddrToAmount[payment.address] = toSatoshis(payment.amount, settings);
+      const { feeSat } = await this._grpc.sendCommand('estimateFee', {
+        AddrToAmount,
+      });
+      payment.fee = toAmount(feeSat, settings);
+      this._nav.goPayBitcoinConfirm();
+    } catch (err) {
+      this._notification.display({ msg: 'Fee estimation failed!', err });
+    }
+  }
+
   /**
    * Send the specified amount as an on-chain transaction to the provided
    * bitcoin address and display a payment confirmation screen.

src/view/pay-bitcoin-mobile.js

@@ -50,7 +50,7 @@ const PayBitcoinView = ({ store, nav, payment }) => (
               autoFocus={true}
               value={store.payment.amount}
               onChangeText={amount => payment.setAmount({ amount })}
-              onSubmitEditing={() => nav.goPayBitcoinConfirm()}
+              onSubmitEditing={() => payment.initPayBitcoinConfirm()}
             />
             <BalanceLabelUnit style={styles.unit}>
               {store.unitFiatLabel}
@@ -60,12 +60,12 @@ const PayBitcoinView = ({ store, nav, payment }) => (
             placeholder="Bitcoin Address"
             value={store.payment.address}
             onChangeText={address => payment.setAddress({ address })}
-            onSubmitEditing={() => nav.goPayBitcoinConfirm()}
+            onSubmitEditing={() => payment.initPayBitcoinConfirm()}
           />
         </FormStretcher>
       </Card>
     </MainContent>
-    <SmallGlasButton onPress={() => nav.goPayBitcoinConfirm()}>
+    <SmallGlasButton onPress={() => payment.initPayBitcoinConfirm()}>
       Next
     </SmallGlasButton>
   </Background>

src/view/pay-bitcoin.js

@@ -51,7 +51,7 @@ const PayBitcoinView = ({ store, nav, payment }) => (
               autoFocus={true}
               value={store.payment.amount}
               onChangeText={amount => payment.setAmount({ amount })}
-              onSubmitEditing={() => nav.goPayBitcoinConfirm()}
+              onSubmitEditing={() => payment.initPayBitcoinConfirm()}
             />
             <BalanceLabelUnit style={styles.unit}>
               {store.unitFiatLabel}
@@ -61,12 +61,12 @@ const PayBitcoinView = ({ store, nav, payment }) => (
             placeholder="Bitcoin Address"
             value={store.payment.address}
             onChangeText={address => payment.setAddress({ address })}
-            onSubmitEditing={() => nav.goPayBitcoinConfirm()}
+            onSubmitEditing={() => payment.initPayBitcoinConfirm()}
           />
         </FormStretcher>
         <PillButton
           style={styles.nextBtn}
-          onPress={() => nav.goPayBitcoinConfirm()}
+          onPress={() => payment.initPayBitcoinConfirm()}
         >
           Next
         </PillButton>

stories/screen-story.js

@@ -108,6 +108,7 @@ const payment = new PaymentAction(store, grpc, nav, notify);
 sinon.stub(payment, 'checkType');
 sinon.stub(payment, 'payBitcoin');
 sinon.stub(payment, 'payLightning');
+sinon.stub(payment, 'initPayBitcoinConfirm');
 const channel = new ChannelAction(store, grpc, nav, notify);
 sinon.stub(channel, 'update');
 sinon.stub(channel, 'connectAndOpen');

test/unit/action/payment.spec.js

@@ -168,6 +168,30 @@ describe('Action Payments Unit Tests', () => {
     });
   });
 
+  describe('initPayBitcoinConfirm()', () => {
+    it('should get estimate and navigate to confirm view', async () => {
+      store.payment.address = 'foo';
+      store.payment.amount = '2000';
+      grpc.sendCommand.withArgs('estimateFee').resolves({
+        feeSat: 10000,
+      });
+      await payment.initPayBitcoinConfirm();
+      expect(nav.goPayBitcoinConfirm, 'was called once');
+      expect(notification.display, 'was not called');
+      expect(store.payment.fee, 'to be', '0.0001');
+    });
+
+    it('should display notification on error', async () => {
+      store.payment.address = 'foo';
+      store.payment.amount = '2000';
+      grpc.sendCommand.withArgs('estimateFee').rejects();
+      await payment.initPayBitcoinConfirm();
+      expect(nav.goPayBitcoinConfirm, 'was not called');
+      expect(notification.display, 'was called once');
+      expect(store.payment.fee, 'to be', '');
+    });
+  });
+
   describe('setAddress()', () => {
     it('should set attribute', () => {
       payment.setAddress({ address: 'some-address' });