目录
概述
为了提高服务的访问速度，减轻geoserver服务的压力，同时避免服务节点出现问题而影响服务访问的稳定性，我们通常会通过部署多个geoserver来解决，但是部署了多个geoserver后，我们需要一个统一的接口提供出来供使用，nginx很好地可以这样的需求，本文讲讲如何通过nginx实现多geoserver服务的负载均衡。
实现效果
实现
1. 多geoserver部署
为了保持geoserver的服务一致，我们先配置好一个geoserver服务，配置好之后将部署的Tomcat复制，克隆多个出来，本文为演示复制了两个（共三个geoserver），修改Tomcat的端口，使三个端口不冲突，复制好之后分别启动三个Tomcat。
2. nginx配置
修改nginx.conf文件，配置信息如下：
#user nobody;
worker_processes 1;
#error_log logs/error.log;
#error_log logs/error.log notice;
#error_log logs/error.log info;
#pid logs/nginx.pid;
events {
worker_connections 1024;
}
http {
include mime.types;
default_type application/octet-stream;
#log_format main '$remote_addr - $remote_user [$time_local] "$request" '
# '$status $body_bytes_sent "$http_referer" '
# '"$http_user_agent" "$http_x_forwarded_for"';
#access_log logs/access.log main;
sendfile on;
#tcp_nopush on;
#keepalive_timeout 0;
keepalive_timeout 65;
#gzip on;
# 反向代理配置
upstream server_list{
# 这个是tomcat的访问路径
server localhost:8081;
server localhost:8082;
server localhost:8083;
}
server {
listen 80;
server_name localhost;
location / {
add_header 'Access-Control-Allow-Origin' $http_origin;
add_header 'Access-Control-Allow-Credentials' 'true';
add_header 'Access-Control-Allow-Methods' 'GET, POST, OPTIONS';
add_header 'Access-Control-Allow-Headers' 'DNT,web-token,app-token,Authorization,Accept,Origin,Keep-Alive,User-Agent,X-Mx-ReqToken,X-Data-Type,X-Auth-Token,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Range';
add_header 'Access-Control-Expose-Headers' 'Content-Length,Content-Range';
if ($request_method = 'OPTIONS') {
add_header 'Access-Control-Max-Age' 1728000;
add_header 'Content-Type' 'text/plain; charset=utf-8';
add_header 'Content-Length' 0;
return 204;
}
root html;
proxy_pass http://server_list;
index index.html index.htm;
}
error_page 500 502 503 504 /50x.html;
location = /50x.html {
root html;
}
}
}
配置好nginx后，启动nginx。
3. 前端调用
根据上述的配置，nginx的端口为80，因此geoserver的地址为http://localhost/geoserver,在ol中的调用代码如下：
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>OpenLayers map preview</title>
<link rel="stylesheet" href="lib/ol/ol.css" rel="external nofollow" type="text/css">
<link rel="stylesheet" href="css/common.css" rel="external nofollow" >
<script src="../ol5/ol.js" type="text/javascript"></script>
</head>
<body>
<div id="map" class="map"></div>
<script>
const options = {
center: [52102781.07568731, 4456849.777083951],
zoom: 3,
minZoom: 0,
maxZoom: 18
}
const base = new ol.layer.Tile({
visible: true,
source: new ol.source.OSM()
});
const wms = new ol.layer.Tile({
source: new ol.source.TileWMS({
url: 'http://localhost/geoserver/mapbox/wms',
params: {'LAYERS': 'mapbox:city', 'TILED': true},
serverType: 'geoserver',
transition: 0
})
})
window.map = new ol.Map({
controls: ol.control.defaults({
attribution: false
}).extend([new ol.control.ScaleLine()]),
target: 'map',
layers: [base, wms],
view: new ol.View({
center: options.center,
zoom: options.zoom,
minZoom: options.minZoom,
maxZoom: options.maxZoom
})
});
</script>
</body>
</html>
