77 lines
2.6 KiB
HTML
77 lines
2.6 KiB
HTML
<!DOCTYPE html>
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<html>
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<head>
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<meta charset="utf-8" />
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<title></title>
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<script>
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document.addEventListener('DOMContentLoaded', () => {
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function xhr(method, url) {
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return new Promise((resolve, reject) => {
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let xhr = new XMLHttpRequest();
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xhr.open(method, url, true);
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xhr.send();
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xhr.onload = () => {
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if (xhr.status >= 200 && xhr.status < 300) {
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resolve(xhr.response);
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} else {
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reject({
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status: xhr.status,
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statusText: xhr.statusText
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});
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}
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};
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xhr.onerror = () => {
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reject({
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status: xhr.status,
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statusText: xhr.statusText
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});
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};
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});
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}
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function send(connectionId, data) {
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var xhr = new XMLHttpRequest();
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var url = `/chat/send?id=${connectionId}`;
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xhr.open("POST", url, true);
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xhr.onreadystatechange = function () {
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if (xhr.readyState == 4 && xhr.status == 200) {
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}
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}
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xhr.send(data);
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}
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function poll(connectionId, xhr) {
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var url = `/chat/poll?id=${connectionId}`;
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xhr.open("POST", url, true);
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xhr.onreadystatechange = () => {
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if (xhr.readyState == 4 && xhr.status == 200) {
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var child = document.createElement('li');
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child.innerText = xhr.response;
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document.getElementById('messages').appendChild(child);
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poll(connectionId, xhr);
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}
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}
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xhr.send(null);
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}
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xhr('GET', '/chat/getid').then(connectionId => {
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document.getElementById('sendmessage').addEventListener('click', () => {
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let data = document.getElementById('data').value;
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send(connectionId, data);
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});
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poll(connectionId, new XMLHttpRequest());
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});
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});
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</script>
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</head>
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<body>
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<h1>Long Polling</h1>
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<input type="text" id="data" />
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<input type="button" id="sendmessage" value="Send" />
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<ul id="messages"></ul>
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</body>
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</html> |