EventSource polyfill - https://html.spec.whatwg.org/multipage/server-sent-events.html#server-sent-events
Пожалуйста не используйте эту обосранную библиотеку!
You can get the code from npm or bower:
npm install event-source-polyfill
bower install event-source-polyfill
Just include src/eventsource.js
or src/eventsource.min.js
in your page to use the polyfill.
Unless a typescript definition file is created for this polyfill, this is how you would use it in an Ionic2 project. It should (in theory) be very similar in an Angular2 project.
npm install event-source-polyfill
Add to (or create) src/app/polyfills.ts (path is relative to where polyfills.ts is) :
import 'path/to/event-source-polyfill/src/eventsource.min.js'
Add anywhere you need access to EventSourcePolyfill class :
declare var EventSourcePolyfill: any;
import { NativeEventSource, EventSourcePolyfill } from 'event-source-polyfill';
const EventSource = NativeEventSource || EventSourcePolyfill;
// OR: may also need to set as global property
global.EventSource = NativeEventSource || EventSourcePolyfill;
- IE 10+, Firefox 3.5+, Chrome 3+, Safari 4+, Opera 12+
- IE 8 - IE 9: XDomainRequest is used internally, which has some limitations (2KB padding in the beginning is required, no way to send cookies, no way to use client certificates)
- It works on Mobile Safari, Opera Mobile, Chrome for Android, Firefox for Android
- It does not work on: Android Browser(requires 4 KB padding after every chunk), Opera Mini
- Simple server-side code
- Cross-domain requests support
- "Last-Event-ID" is sent in a query string (CORS + "Last-Event-ID" header is not supported by all browsers)
- It is required to send 2 KB padding for IE < 10 and Chrome < 13 at the top of the response stream (the polyfill sends
padding=true
query argument) - You need to send "comment" messages each 15-30 seconds, these messages will be used as heartbeat to detect disconnects - see https://bugzilla.mozilla.org/show_bug.cgi?id=444328
- To build EventSource, just install npm modules (
npm install
) and then run the build (npm run build
). It should generate a new version ofsrc/eventsource.min.js
.
- If you are using HTTP Basic Authentication, you can embed credentials into the URL -
http://username:[email protected]
.
var es = new EventSourcePolyfill('/events', {
headers: {
'X-Custom-Header': 'value'
}
});
- Some server require a special query parameter name for last-event-id, you can change that via option
- The default is
lastEventId
- Example for mercure-hub (https://mercure.rocks/)
var es = new EventSourcePolyfill(hubUrl, {
lastEventIdQueryParameterName: 'Last-Event-Id'
});
- https://github.com/remy/polyfills/blob/master/EventSource.js by Remy Sharp
- https://github.com/rwldrn/jquery.eventsource by Rick Waldron
- https://github.com/amvtek/EventSource by AmvTek
var PORT = 8081;
var http = require("http");
var fs = require("fs");
var url = require("url");
http.createServer(function (request, response) {
var parsedURL = url.parse(request.url, true);
var pathname = parsedURL.pathname;
if (pathname === "/events.php") {
response.writeHead(200, {
"Content-Type": "text/event-stream",
"Cache-Control": "no-store",
"Access-Control-Allow-Origin": "*"
});
var padding = new Array(2049);
response.write(":" + padding.join(" ") + "\n"); // 2kB padding for IE
response.write("retry: 2000\n");
var lastEventId = Number(request.headers["last-event-id"]) || Number(parsedURL.query.lastEventId) || 0;
var timeoutId = 0;
var i = lastEventId;
var c = i + 100;
var f = function () {
if (++i < c) {
response.write("id: " + i + "\n");
response.write("data: " + i + "\n\n");
timeoutId = setTimeout(f, 1000);
} else {
response.end();
}
};
f();
response.on("close", function () {
clearTimeout(timeoutId);
});
} else {
if (pathname === "/") {
pathname = "/index.html";
}
if (pathname === "/index.html" || pathname === "../src/eventsource.js") {
response.writeHead(200, {
"Content-Type": pathname === "/index.html" ? "text/html" : "text/javascript"
});
response.write(fs.readFileSync(__dirname + pathname));
}
response.end();
}
}).listen(PORT);
<?php
header("Content-Type: text/event-stream");
header("Cache-Control: no-store");
header("Access-Control-Allow-Origin: *");
$lastEventId = floatval(isset($_SERVER["HTTP_LAST_EVENT_ID"]) ? $_SERVER["HTTP_LAST_EVENT_ID"] : 0);
if ($lastEventId == 0) {
$lastEventId = floatval(isset($_GET["lastEventId"]) ? $_GET["lastEventId"] : 0);
}
echo ":" . str_repeat(" ", 2048) . "\n"; // 2 kB padding for IE
echo "retry: 2000\n";
// event-stream
$i = $lastEventId;
$c = $i + 100;
while (++$i < $c) {
echo "id: " . $i . "\n";
echo "data: " . $i . ";\n\n";
ob_flush();
flush();
sleep(1);
}
?>
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>EventSource example</title>
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<script src="../src/eventsource.js"></script>
<script>
var es = new EventSource("events.php");
var listener = function (event) {
var div = document.createElement("div");
var type = event.type;
div.appendChild(document.createTextNode(type + ": " + (type === "message" ? event.data : es.url)));
document.body.appendChild(div);
};
es.addEventListener("open", listener);
es.addEventListener("message", listener);
es.addEventListener("error", listener);
</script>
</head>
<body>
</body>
</html>
With some dynamic imports it may work in node.js:
Install the library and the dependency:
npm install @titelmedia/node-fetch
npm install event-source-polyfill
x.js:
// The @titelmedia/node-fetch is used instead of node-fetch as it supports ReadableStream Web API
import('@titelmedia/node-fetch').then(function (fetch) {
globalThis.fetch = fetch.default;
globalThis.Response = fetch.default.Response;
import('event-source-polyfill').then(function (x) {
var es = new x.default.EventSourcePolyfill('http://localhost:8004/events');
es.onerror = es.onopen = es.onmessage = function (event) {
console.log(event.type + ': ' + event.data);
};
});
});
node --experimental-modules ./x.js
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