Merge pull request #37 from MyEtherWallet/bity_stop_refresh

Sagas: Adjust bity saga to allow for cancelled polling, and stop poll…

.eslintrc.json

@@ -24,6 +24,7 @@
     "no-underscore-dangle": 0,
     "no-console": 0,
     "no-unused-vars": 0,
+    "no-constant-condition": 0,
     "no-trailing-spaces": [1, { "skipBlankLines": true }],
     "no-unreachable": 1,
     "no-alert": 0,

common/actions/swap.js

@@ -8,7 +8,8 @@ import {
   SWAP_PART_TWO_COMPLETE,
   SWAP_DESTINATION_ADDRESS,
   SWAP_RESTART,
-  SWAP_LOAD_BITY_RATES
+  SWAP_LOAD_BITY_RATES,
+  SWAP_STOP_LOAD_BITY_RATES
 } from './swapConstants';
 
 export const originKindSwap = value => {
@@ -78,3 +79,9 @@ export const loadBityRates = () => {
     type: SWAP_LOAD_BITY_RATES
   };
 };
+
+export const stopLoadBityRates = () => {
+  return {
+    type: SWAP_STOP_LOAD_BITY_RATES
+  };
+};

common/actions/swapConstants.js

@@ -8,3 +8,4 @@ export const SWAP_PART_TWO_COMPLETE = 'SWAP_PART_TWO_COMPLETE';
 export const SWAP_DESTINATION_ADDRESS = 'SWAP_DESTINATION_ADDRESS';
 export const SWAP_RESTART = 'SWAP_RESTART';
 export const SWAP_LOAD_BITY_RATES = 'SWAP_LOAD_BITY_RATES';
+export const SWAP_STOP_LOAD_BITY_RATES = 'SWAP_STOP_LOAD_BITY_RATES';

common/containers/Tabs/Swap/components/receivingAddress.js

@@ -10,7 +10,8 @@ export default class ReceivingAddress extends Component {
     destinationKind: PropTypes.string.isRequired,
     destinationAddressSwap: PropTypes.func.isRequired,
     destinationAddress: PropTypes.string,
-    partTwoCompleteSwap: PropTypes.func
+    partTwoCompleteSwap: PropTypes.func,
+    stopLoadBityRates: PropTypes.func
   };
 
   onChangeDestinationAddress = (event: SyntheticInputEvent) => {
@@ -19,6 +20,7 @@ export default class ReceivingAddress extends Component {
   };
 
   onClickPartTwoComplete = () => {
+    this.props.stopLoadBityRates();
     this.props.partTwoCompleteSwap(true);
   };
 

common/containers/Tabs/Swap/index.js

@@ -33,7 +33,8 @@ class Swap extends Component {
     destinationAddressSwap: PropTypes.func,
     restartSwap: PropTypes.func,
     partTwoCompleteSwap: PropTypes.func,
-    partTwoComplete: PropTypes.bool
+    partTwoComplete: PropTypes.bool,
+    stopLoadBityRates: PropTypes.func
   };
 
   componentDidMount() {
@@ -59,7 +60,8 @@ class Swap extends Component {
       destinationAddress,
       restartSwap,
       partTwoCompleteSwap,
-      partTwoComplete
+      partTwoComplete,
+      stopLoadBityRates
     } = this.props;
 
     let wantToSwapMyProps = {
@@ -88,7 +90,8 @@ class Swap extends Component {
       destinationKind,
       destinationAddressSwap,
       destinationAddress,
-      partTwoCompleteSwap
+      partTwoCompleteSwap,
+      stopLoadBityRates
     };
 
     const referenceNumber = '2341asdfads';

common/sagas/bity.js

@@ -1,23 +1,45 @@
 // @flow
 
-import { takeLatest, call, apply, put, select, fork } from 'redux-saga/effects';
+import { call, put, fork, take, cancel, cancelled } from 'redux-saga/effects';
+
 import type { Effect } from 'redux-saga/effects';
 import { delay } from 'redux-saga';
 import { updateBityRatesSwap } from 'actions/swap';
-import { SWAP_LOAD_BITY_RATES } from 'actions/swapConstants';
+import {
+  SWAP_LOAD_BITY_RATES,
+  SWAP_STOP_LOAD_BITY_RATES
+} from 'actions/swapConstants';
 import type { UnlockPrivateKeyAction } from 'actions/wallet';
 import { getAllRates } from 'api/bity';
 
 export function* loadBityRates(action?: any): Generator<Effect, void, any> {
-  if (!action) return;
-  // eslint-disable-next-line
+  try {
     while (true) {
+      // TODO - yield put(actions.requestStart()) if we want to display swap refresh status
+      // network request
       const data = yield call(getAllRates);
+      // action
       yield put(updateBityRatesSwap(data));
+      // wait 5 seconds before refreshing rates
       yield call(delay, 5000);
     }
+  } finally {
+    if (yield cancelled()) {
+      // TODO - implement request cancel if needed
+      // yield put(actions.requestFailure('Request cancelled!'))
+    }
+  }
 }
 
 export default function* bitySaga(): Generator<Effect, void, any> {
-  yield takeLatest(SWAP_LOAD_BITY_RATES, loadBityRates);
+  while (yield take(SWAP_LOAD_BITY_RATES)) {
+    // starts the task in the background
+    const loadBityRatesTask = yield fork(loadBityRates);
+
+    // wait for the user to get to point where refresh is no longer needed
+    yield take(SWAP_STOP_LOAD_BITY_RATES);
+    // cancel the background task
+    // this will cause the forked loadBityRates task to jump into its finally block
+    yield cancel(loadBityRatesTask);
+  }
 }