备注：
即时消息的安全对于我们来说是比较重要的，作者在设计Nchan 的时候已经考虑了
a. nchan_authorize_request （Hooks and Callbacks）可以集成后端服务
配置如下：
upstream my_app {
server 127.0.0.1:8080;
}
location = /auth {
proxy_pass http://my_app/pubsub_authorize;
proxy_pass_request_body off;
proxy_set_header Content-Length "";
proxy_set_header X-Subscriber-Type $nchan_subscriber_type;
proxy_set_header X-Publisher-Type $nchan_publisher_type;
proxy_set_header X-Prev-Message-Id $nchan_prev_message_id;
proxy_set_header X-Channel-Id $nchan_channel_id;
proxy_set_header X-Original-URI $request_uri;
proxy_set_header X-Forwarded-For $remote_addr;
}
location ~ /pubsub/auth/(w+)$ {
nchan_channel_id $1;
nchan_authorize_request /auth;
nchan_pubsub;
nchan_channel_group test;
}
b. 使用内部channel ，控制访问ip
// 只能内部访问
http {
server {
#available only on localhost
listen 127.0.0.1:8080;
location ~ /pub/(w+)$ {
nchan_publisher;
nchan_channel_group my_app_group;
nchan_channel_id $1;
}
}
server {
#available to the world
listen 80;
location ~ /sub/(w+)$ {
nchan_subscriber;
nchan_channel_group my_app_group;
nchan_channel_id $1;
}
}
}
// ip 过滤
server {
#available to the world
listen 80;
location ~ /pub/(w+)$ {
allow 127.0.0.1;
deny all;
nchan_publisher;
nchan_channel_group my_app_group;
nchan_channel_id $1;
}
c. 对于重要的，外部服务进行加密
http {
server {
#available only on localhost
listen 127.0.0.1:8080;
#...publisher endpoint config
}
server {
#available to the world
listen 443 ssl;
#SSL config goes here
location ~ /sub/(w+)$ {
nchan_subscriber;
nchan_channel_group my_app_group;
nchan_channel_id $1;
}
}
}