Merge pull request #1237 from 0xProject/feature/instant/buy-quote-heartbeat

[instant] Heartbeats for account info and buy quotes

3 files changed, 62 insertions, 2 deletions

diff --git a/packages/instant/src/util/buy_quote_updater.ts b/packages/instant/src/util/buy_quote_updater.ts
index e697d3ef7..c33e28f1c 100644
--- a/packages/instant/src/util/buy_quote_updater.ts
+++ b/packages/instant/src/util/buy_quote_updater.ts
@@ -16,12 +16,15 @@ export const buyQuoteUpdater = {
         dispatch: Dispatch<Action>,
         asset: ERC20Asset,
         assetAmount: BigNumber,
+        setPending = true,
         affiliateInfo?: AffiliateInfo,
     ): Promise<void> => {
         // get a new buy quote.
         const baseUnitValue = Web3Wrapper.toBaseUnitAmount(assetAmount, asset.metaData.decimals);
-        // mark quote as pending
-        dispatch(actions.setQuoteRequestStatePending());
+        if (setPending) {
+            // mark quote as pending
+            dispatch(actions.setQuoteRequestStatePending());
+        }
         const feePercentage = oc(affiliateInfo).feePercentage();
         let newBuyQuote: BuyQuote | undefined;
         try {
diff --git a/packages/instant/src/util/heartbeater.ts b/packages/instant/src/util/heartbeater.ts
new file mode 100644
index 000000000..e700d489e
--- /dev/null
+++ b/packages/instant/src/util/heartbeater.ts
@@ -0,0 +1,35 @@
+import { intervalUtils } from '@0x/utils';
+import * as _ from 'lodash';
+
+type HeartbeatableFunction = () => Promise<void>;
+export class Heartbeater {
+    private _intervalId?: NodeJS.Timer;
+    private readonly _performImmediatelyOnStart: boolean;
+    private readonly _performFunction: HeartbeatableFunction;
+
+    public constructor(performingFunctionAsync: HeartbeatableFunction, performImmediatelyOnStart: boolean) {
+        this._performFunction = performingFunctionAsync;
+        this._performImmediatelyOnStart = performImmediatelyOnStart;
+    }
+
+    public start(intervalTimeMs: number): void {
+        if (!_.isUndefined(this._intervalId)) {
+            throw new Error('Heartbeat is running, please stop before restarting');
+        }
+
+        if (this._performImmediatelyOnStart) {
+            // tslint:disable-next-line:no-floating-promises
+            this._performFunction();
+        }
+
+        // tslint:disable-next-line:no-unbound-method
+        this._intervalId = intervalUtils.setAsyncExcludingInterval(this._performFunction, intervalTimeMs, _.noop);
+    }
+
+    public stop(): void {
+        if (this._intervalId) {
+            intervalUtils.clearInterval(this._intervalId);
+        }
+        this._intervalId = undefined;
+    }
+}
diff --git a/packages/instant/src/util/heartbeater_factory.ts b/packages/instant/src/util/heartbeater_factory.ts
new file mode 100644
index 000000000..96a8ac4e6
--- /dev/null
+++ b/packages/instant/src/util/heartbeater_factory.ts
@@ -0,0 +1,22 @@
+import { asyncData } from '../redux/async_data';
+import { Store } from '../redux/store';
+
+import { Heartbeater } from './heartbeater';
+
+export interface HeartbeatFactoryOptions {
+    store: Store;
+    shouldPerformImmediatelyOnStart: boolean;
+}
+export const generateAccountHeartbeater = (options: HeartbeatFactoryOptions): Heartbeater => {
+    const { store, shouldPerformImmediatelyOnStart } = options;
+    return new Heartbeater(async () => {
+        await asyncData.fetchAccountInfoAndDispatchToStore({ store, shouldSetToLoading: false });
+    }, shouldPerformImmediatelyOnStart);
+};
+
+export const generateBuyQuoteHeartbeater = (options: HeartbeatFactoryOptions): Heartbeater => {
+    const { store, shouldPerformImmediatelyOnStart } = options;
+    return new Heartbeater(async () => {
+        await asyncData.fetchCurrentBuyQuoteAndDispatchToStore({ store, shouldSetPending: false });
+    }, shouldPerformImmediatelyOnStart);
+};