@baqhub/sdk
Version:
The official JavaScript SDK for the BAQ federated app platform.
122 lines (121 loc) • 5.17 kB
JavaScript
;
// MIT License
Object.defineProperty(exports, "__esModule", { value: true });
exports.fetchEventSource = fetchEventSource;
// Copyright (c) Microsoft Corporation.
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE
//
// File from:
// https://github.com/Azure/fetch-event-source/blob/main/src/fetch.ts
//
// Modifications:
// - Allow headers to be rebuilt on each request.
const eventSourceParse_js_1 = require("./eventSourceParse.js");
const eventStreamContentType = "text/event-stream";
const defaultRetryInterval = 1000; // 1s
const defaultMonitorInterval = 40 * 1000; // 40s
function fetchEventSource(eventSourceFetch, input, options) {
return new Promise(resolve => {
const { onMessage, buildHeaders, signal, ...rest } = options;
if (signal?.aborted) {
return;
}
// function onVisibilityChange() {
// abortController.abort(); // close existing request on every visibility change
// if (!document.hidden) {
// create(); // page is now visible again, recreate request.
// }
// }
// if (!openWhenHidden) {
// document.addEventListener("visibilitychange", onVisibilityChange);
// }
let abortController;
let lastEventId = undefined;
let retryInterval = defaultRetryInterval;
let retryTimer = 0;
let monitorTimer = 0;
function dispose() {
// if (!openWhenHidden) {
// document.removeEventListener("visibilitychange", onVisibilityChange);
// }
clearTimeout(retryTimer);
clearTimeout(monitorTimer);
abortController.abort();
}
// If the incoming signal aborts, dispose resources and resolve.
signal?.addEventListener("abort", () => {
dispose();
resolve();
});
function scheduleRetry() {
dispose();
retryTimer = setTimeout(create, retryInterval);
}
function resetMonitor() {
clearTimeout(monitorTimer);
monitorTimer = setTimeout(scheduleRetry, defaultMonitorInterval);
}
function onMessageInternal(event) {
resetMonitor();
return onMessage(event);
}
async function create() {
abortController = new AbortController();
try {
while (!abortController.signal.aborted) {
const headers = {
...buildHeaders?.(lastEventId),
Accept: eventStreamContentType,
};
const response = await eventSourceFetch(input, {
...rest,
headers,
signal: abortController.signal,
});
await defaultOnOpen(response);
resetMonitor();
await (0, eventSourceParse_js_1.getBytes)(response.body, (0, eventSourceParse_js_1.getLines)((0, eventSourceParse_js_1.getMessages)(id => {
if (id) {
// Store the id and send it back on the next retry.
lastEventId = id;
}
else {
// Don't send the last-event-id header anymore.
lastEventId = undefined;
}
}, retry => {
retryInterval = retry;
}, onMessageInternal)));
}
}
catch (err) {
if (abortController.signal.aborted) {
return;
}
// If we haven't aborted the request ourselves, retry.
scheduleRetry();
}
}
create();
});
}
function defaultOnOpen(response) {
const contentType = response.headers.get("content-type");
if (!contentType?.startsWith(eventStreamContentType)) {
throw new Error(`Expected content-type to be ${eventStreamContentType}, Actual: ${contentType}`);
}
}