基于 SSE(Server-Sent Events) 技术，实现聊天室功能
| 实现方式 | 优点 | 缺点 | 使用场景 |
|---|---|---|---|
| http轮询 | 简单易用，兼容性好，流量可控 | 高延迟，服务器负载高，带宽使用高 | 对实时性要求不高，低并发，对带宽不敏感 |
| SSE | 实时更新，服务器负载低、带宽使用少（相比轮训），实现简单且支持自动重连 | 单向通信，数据只能从服务端到客户端 | 实时性高且服务器负载较小的场景，如股票行情、新闻推送、在线聊天等 |
| websocket | 实时更新，支持全双工通信 | 实现和维护相比SSE复杂，需要处理连接的建立、重连、断开等 | 聊天应用、在线游戏、视频会议等 |
附上代码的连接 GitHub
如果没有安装，自行搜索解决，此处不表
|____docker
| |____docker-compose.yaml
| |____php.ini-production
| |____Dockerfile
| |____www.conf.ini
| |____.env
| |____nginx.conf
|____index.html
|____sse.php
|____send.php
# 使用指定基础镜像
FROM php:8.2-fpm-bullseye
# 设置环境变量 DEBIAN_FRONTEND
ENV DEBIAN_FRONTEND noninteractive
COPY www.conf.ini /usr/local/etc/php-fpm.d/www.conf
# 安装必要的软件包和依赖项
RUN apt-get update \
&& cp /usr/local/etc/php/php.ini-production /usr/local/etc/php/php.ini
RUN docker-php-ext-install pcntl bcmath mysqli pdo_mysql \
&& docker-php-ext-enable pcntl bcmath mysqli
# 安装 git unzip (安装laravel需要)
RUN apt install git unzip -y
RUN pecl install redis \
&& docker-php-ext-enable redis
RUN apt install -y redis-server redis-tools \
&& /etc/init.d/redis-server start
# 安装 composer
RUN curl -sS https://getcomposer.org/installer | php -- --install-dir=/usr/local/bin --filename=composer; 禁用输出缓冲
output_buffering = Off
; 启用隐式刷新
implicit_flush = Onworker_processes 1;
events { worker_connections 1024; }
http {
keepalive_timeout 65;
keepalive_requests 100;
# 禁用输出缓冲
fastcgi_buffering off;
proxy_buffering off;
gzip off;
server {
listen 80;
server_name localhost;
root /var/www;
index index.php index.html index.htm;
location / {
try_files $uri $uri/ =404;
}
location /sse.php {
# 关闭缓冲区以避免延迟
proxy_buffering off;
proxy_cache off;
chunked_transfer_encoding off;
# 确保 SSE 响应头正确
add_header Cache-Control "no-cache";
add_header Content-Type "text/event-stream";
}
location ~ \.php$ {
# include snippets/fastcgi-php.conf;
fastcgi_pass sse-chat-php:9000;
fastcgi_index index.php;
fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
include fastcgi_params;
# 禁用 FastCGI 缓冲
fastcgi_buffering off;
fastcgi_keep_conn on;
# 设置缓冲区大小
fastcgi_buffers 8 16k;
fastcgi_buffer_size 32k;
}
}
}version: '3'
services:
sse-chat-nginx:
image: nginx:1.27.0
container_name: sse-chat-nginx
ports:
- "80:80"
volumes:
- ./nginx.conf:/etc/nginx/nginx.conf
- ../:/var/www
depends_on:
- sse-chat-php
- sse-chat-redis
networks:
- local_host
sse-chat-php:
build:
context: .
dockerfile: Dockerfile
container_name: sse-chat-php
ports:
- 8081:8081
volumes:
- ../:/var/www
stdin_open: true
tty: true
working_dir: /var/www
restart: always
networks:
- local_host
sse-chat-redis:
container_name: sse-chat-redis
image: redis:alpine
ports:
- 16379:6379
restart: always
networks:
- local_host
networks:
local_host:
driver: bridge
cd docker && docker-compose up -d
<?php
$name = $_GET['name'] ?? '';
$message = $_GET['message'] ?? '';
if (empty($name) || empty($message)) {
echo json_encode([
'code' => -1,
'msg' => 'fail',
]);
} else {
$host = 'sse-chat-redis';
$port = '6379';
$redis = new \Redis();
$redis->connect($host, $port);
$redis->rpush('chat_room_1', json_encode([
'name' => $name,
'message' => $message,
'created_at' => date('Y-m-d H:i:s'),
], JSON_UNESCAPED_UNICODE));
echo json_encode([
'code' => 0,
'msg' => 'success',
]);
}curl localhost/send.php?name=Alice&message=This_is_Alice
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>SSE Chat</title>
<script type="text/javascript">
document.addEventListener('DOMContentLoaded', function () {
if (typeof (EventSource) !== "undefined") {
const source = new EventSource('sse.php');
source.addEventListener('update', function (event) {
const data = JSON.parse(event.data);
const messageElement = document.createElement('p');
messageElement.textContent = data.created_at + "</br>" + data.name + ":" + data.message;
document.getElementById('messages').appendChild(messageElement);
console.log('id:', data.id);
});
source.addEventListener('close', function (event) {
const messageElement = document.createElement('p');
messageElement.textContent = "Connection closed by server.";
document.getElementById('messages').appendChild(messageElement);
source.close();
});
} else {
alert("Your browser does not support Server-Sent Events.");
}
});
</script>
</head>
<body>
<h1>SSE Chat</h1>
<div id="messages"></div>
</body>
</html><?php
require './vendor/autoload.php';
set_time_limit(0);
header('Content-Type: text/event-stream');
header('Cache-Control: no-cache');
header('Connection: keep-alive');
// 设置重试间隔时间
echo "retry: 2000\n\n";
ob_flush();
flush();
$host = 'sse-chat-redis';
$port = '6379';
$redis = new \Redis();
$redis->connect($host, $port);
while (true) {
if (!$messageList = $redis->lpop('chat_room_1', 2)) {
continue;
}
foreach ($messageList as $message) {
$message = json_decode($message, true);
$lastEventId = $id = $message['id'];
// 推送数据到客户端
echo "id: " . $id . "\n";
echo "event: update\n";
echo "data: " . json_encode($message, JSON_UNESCAPED_UNICODE) . "\n\n";
ob_flush();
flush();
}
usleep(500);
}