bugfix: ngx_http_lua_gen_chunk_name should take into account full file name instead of last path component

[lonerr]

I hope this should solve the following collision:

server {
    listen 80;
    include /etc/nginx/a/proxy.conf;
    include /etc/nginx/b/proxy.conf;
}

Where /etc/nginx/a/proxy.conf is

location /a/ {
    content_by_lua_block { ngx.say("/a/ is called") }
}

and /etc/nginx/b/proxy.conf is

location /b/ {
    content_by_lua_block { ngx.say("/b/ is called") }
}

I hereby granted the copyright of the changes in this pull request
to the authors of this lua-nginx-module project.

[felixcolaci]

Hi Guys,
thank you for your great work on the open resty project. It's really helpful to be able to integrate lua with nginx.
Never the less we are experiencing serious trouble with this issue in production right now. Can you give us any hint on when this issue will be resolved and integrated?
Kind regards & keep up the great work!
Felix

[agentzh]

@lonerr Are you seeing that all the travis ci jobs are failing horribly in this PR?

https://travis-ci.org/openresty/lua-nginx-module/builds/459270635?utm_source=github_status&utm_medium=notification

I'm not sure what problem this PR tries to address. The *_by_lua_block directives do not involve any Lua source file paths anyway.

[lonerr]

@agentzh yes, I saw. But it seems that all these travis errors are about changed format of error log messages. As for the problem itself, please have a look at the simplest test case below:

/etc/nginx/nginx.conf

user  nginx;
error_log /var/log/nginx/error.log notice;
pid /var/run/nginx.pid;

load_module modules/ndk_http_module-debug.so;
load_module modules/ngx_http_lua_module-debug.so;

events {}

http {
    access_log /var/log/nginx/access.log;
    server {
        listen 80;
        include /etc/nginx/a/proxy.conf;
        include /etc/nginx/b/proxy.conf;
    }
}

/etc/nginx/a/proxy.conf

location /a/ {
    content_by_lua_block { ngx.say("/a/ is called") }
}

/etc/nginx/b/proxy.conf

location /b/ {
  content_by_lua_block { ngx.say("/b/ is called") }
}

The results are unexpectedly incorrect:

% curl http://ubuntu-18.04.stand/a/
/a/ is called

% curl http://ubuntu-18.04.stand/b/
/a/ is called

Adding lua_code_cache off; corrects the behavior:

% curl http://ubuntu-18.04.stand/a/
/a/ is called

% curl http://ubuntu-18.04.stand/b/
/b/ is called

Hope this helps.

[agentzh]

@lonerr OK, I see what's going on here. I proposed a pull request to fix this properly. See #1469.