Lua 条目线程中止：运行时错误：尝试连接字段'cookie_sessionid'(无值)

Question

/etc/nginx/站点启用/默认:

location /pine {
    add_header Access-Control-Allow-Origin http://localhost:6285;
    add_header Access-Control-Allow-Credentials true;
    access_by_lua_file /home/akuznetsov/auth.lua;
    proxy_pass http://localhost:9100;
}

auth.loa（版本1，运行良好）：

ngx.req.set_header('x-user-id', ngx.var.cookie_sessionid)

auth.loa（版本2，不工作）：

ngx.req.set_header('x-user-id', 'session:' .. ngx.var.cookie_sessionid)

在/var/log/nginx/error.log中，我得到了这个错误：

2016/04/06 16:13:10 [error] 14183#0: *1 lua entry thread aborted: runtime error: /home/akuznetsov/auth.lua:2: attempt to concatenate field 'cookie_sessionid' (a nil value)
stack traceback:
coroutine 0:
/home/akuznetsov/auth.lua:2: in function </home/akuznetsov/auth.lua:1>, client: 127.0.0.1, server: localhost, request: "OPTIONS /pine HTTP/1.1", host: "localhost", referrer: "http://localhost:6285/chart/kjckCBcG/?pine=http://localhost/pine"

concat怎么了？

Answer 1

ngx.var.cookie_sessionid是nil，正如消息告诉您的，您不能将其连接（即..）。为if检查提供逻辑来处理这种情况，或者如果您同意使用空字符串作为默认值，则使用ngx.req.set_header('x-user-id', 'session:' .. ngx.var.cookie_sessionid or "")。