confd: 本地配置文件的管理工具
目录
说明
confd从etcd或者consul等获取数据更新，更新本地的配置文件后，重新加载目标应用。
confd支持一下backends:
etcd
consul
vault
environment variables
redis
zookeeper
dynamodb
rancher
ssm (AWS Simple Systems Manager Parameter Store)
使用
在backends中写入配置项的值，以etcd为例:
etcdctl set /myapp/subdomain myapp
etcdctl set /myapp/upstream/app2 "10.0.1.100:80"
etcdctl set /myapp/upstream/app1 "10.0.1.101:80"
etcdctl set /yourapp/subdomain yourapp
etcdctl set /yourapp/upstream/app2 "10.0.1.102:80"
etcdctl set /yourapp/upstream/app1 "10.0.1.103:80"
在/etc/confd/conf.d/中创建应用模版：
[template]
prefix = "/myapp"
src = "nginx.tmpl"
dest = "/tmp/myapp.conf"
owner = "nginx"
mode = "0644"
keys = [
"/subdomain",
"/upstream",
]
check_cmd = "/usr/sbin/nginx -t -c {{.src }}"
reload_cmd = "/usr/sbin/service nginx reload"
在/etc/confd/templates中创建配置模版：
upstream {{getv "/subdomain"}} {
{{range getvs "/upstream/*"}}
server {{.}};
{{end}}
}
server {
server_name {{getv "/subdomain"}}.example.com;
location / {
proxy_pass http://{{getv "/subdomain"}};
proxy_redirect off;
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
}
}
启动confd之后，confd就会监听etcd中的key，根据应用模版中的内容，从配置模版生成配置文件。
confd -onetime -backend etcd -node http://127.0.0.1:2379
confd -backend etcd -node http://127.0.0.1:2379
配置文件生成后，confd执行应用模版中指定命令进行配置文件的重新加载。
如果使用-onetime，则只生成一次，不持续监听、动态更新。
参考
