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nginxluacorsreverse-proxy

lua entry thread aborted: runtime error: attempt to concatenate field 'cookie_sessionid' (a nil value)

/etc/nginx/sites-enabled/default:

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.lua (version 1, works fine):

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

auth.lua (version 2, not working):

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

in /var/log/nginx/error.log i get this error:

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"

What's wrong with concat?

Solution

  • ngx.var.cookie_sessionid is nil and just as message tell you, you can't concatenate (i.e. ..) that. Provide if check with logic to handle this case or use ngx.req.set_header('x-user-id', 'session:' .. ngx.var.cookie_sessionid or "") if you okay with using empty string as default.