openresty ngx_ Lua execution phase

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openresty ngx_lua Execution phase

       

                

                                

nginx http Execution phase

          

nginx http Execution phase

# ngx_http_core_module.h
typedef enum {
    NGX_HTTP_POST_READ_PHASE = 0,

    NGX_HTTP_SERVER_REWRITE_PHASE,

    NGX_HTTP_FIND_CONFIG_PHASE,
    NGX_HTTP_REWRITE_PHASE,
    NGX_HTTP_POST_REWRITE_PHASE,

    NGX_HTTP_PREACCESS_PHASE,

    NGX_HTTP_ACCESS_PHASE,
    NGX_HTTP_POST_ACCESS_PHASE,

    NGX_HTTP_PRECONTENT_PHASE,

    NGX_HTTP_CONTENT_PHASE,

    NGX_HTTP_LOG_PHASE
} ngx_http_phases;

          

Description of the implementation phase

NGX_HTTP_POST_READ_PHASE = 0,
*  Accept and read the request 

NGX_HTTP_SERVER_REWRITE_PHASE,
*  modify url Stage , Usually there is redirection 、 Variable is set 

NGX_HTTP_FIND_CONFIG_PHASE,
*  lookup url Corresponding configuration , If it matches location

NGX_HTTP_REWRITE_PHASE,
*  Match to location after , May enter again NGX_HTTP_SERVER_REWRITE_PHASE

NGX_HTTP_POST_REWRITE_PHASE,
*  Check url Whether the stage has been executed 4, If executed , Enter the stage again 3
*  The maximum number of checks is 10, More than will report error 

NGX_HTTP_PREACCESS_PHASE,
*  Request resource speed limit and other operations 

NGX_HTTP_ACCESS_PHASE,
*  Access control , Such as restrictions ip visit 

NGX_HTTP_POST_ACCESS_PHASE,
*  verification NGX_HTTP_ACCESS_PHASE（ Access control ） result , If yes, continue 

NGX_HTTP_PRECONTENT_PHASE,
* try_files The directive takes effect 

NGX_HTTP_CONTENT_PHASE,
*  Handle http Request content , Generally, you need to interact with back-end applications 

NGX_HTTP_LOG_PHASE
*  Log output 

        

             

                                

ngx_lua Execution phase

         

              

        

Execution order

init_by_lua_block
init_worker_by_lua_block

set_by_lua_block
rewrite_by_lua_block
access_by_lua_block
content_by_lua_block

header_filter_by_lua_block
body_filter_by_lua_block
log_filter_by_lua_block

            

init_by_lua_block：nginx initialization 、 Execute on restart , stay http Set in the module

http {
    include       mime.types;
    default_type  application/octet-stream;
 
    init_by_lua_block {
        local uuid = require 'resty.jit-uuid';
        uuid.seed();
    } 

    ...

}

          

init_by_lua_file： The functions and init_by_lua_block identical , The code block is saved in a file

http {
    include       mime.types;
    default_type  application/octet-stream;
 
    init_worker_by_lua_file /usr/local/nginx/conf/init.lua

    ...

}


# /usr/local/nginx/conf/init.lua  The contents of the document 
local uuid = require 'resty.jit-uuid';
uuid.seed();

           

init_worker_by_lua_block：master After the process starts , Execute related code blocks , stay http Set in the module

#  It can be used to perform scheduled tasks 、 Back end health check 
http {
    include       mime.types;
    default_type  application/octet-stream;
 
    init_worker_by_lua_block {
        ...
    } 

    ...

}

              

set_by_lua_block： Execute code block , And return the result , stay server、location Set

 Grammar format ：set_by_lua_block $result {...}
*  This command is a blocking command , The executed statement block should be as short as possible 、 fast , Avoid taking too much time 
*  Disable ：ngx.say()、ngx.exit()、ngx.sleep() Wait for the order 

server {
    listen       80;
    server_name  localhost; 

    set $a "";
    set_by_lua_block $a {
        return "1";
    }


    location / {
        root   /usr/local/openresty/nginx/html;
        index  index.html index.htm;
    }

    ...

 }

              

rewrite_by_lua_block： Rewrite phase execution , Can be found in http、server、location Set in

 Grammar format ：rewrite_by_lua_block {...}
*  The statement block will be executed at the end , It can be done by rewrite_by_lua_no_postpone（ Default off） Change the order of execution 
*  All... Can be called ngx api

# a The value of is 2
server {
    listen       80;
    server_name  localhost; 

    set $a "1";
    rewrite_by_lua_block {
        ngx_var_a="2";
    }
    set $a "3"


    location / {
        root   /usr/local/openresty/nginx/html;
        index  index.html index.htm;
    }

    ...

 }


# http Stage configuration ：rewrite_by_lua_no_postpone on
# a The value of is 3
server {
    listen       80;
    server_name  localhost; 

    set $a "1";
    rewrite_by_lua_block {
        ngx_var_a="2";
    }
    set $a "3"


    location / {
        root   /usr/local/openresty/nginx/html;
        index  index.html index.htm;
    }

    ...

 }

             

access_by_lua_block：access Stage execution statement block （ Permission check 、 Black and white list ）, stay http、server、location Set in

 Grammar format ：access_by_lua_block {...}
*  The statement block will be executed at the end , It can be done by access_by_lua_no_postpone（ Default off） Change the order of execution 
*  All... Can be called ngx api
*  application ： Store the black and white list in redis、 In shared memory , Dynamically set the black and white list 

         

content_by_lua_block： The content processing phase executes , Set the output content , stay location Set in

 Grammar format ：content_by_lua_block {...}
*  All... Can be called ngx api
*  If used in conjunction with other content execution phase statements ,content_by_lua_block May not execute 

location / {

    content_by_lua_block {
        ngx.say("hello gtlx");
    }
    
    echo "test"    # Only output test, No output hello gtlx
}

               

content_by_lua_file： And content_by_lua_block identical , Statements are saved in a file , stay location Set in

 Grammar format ：content_by_lua_file file
*  All... Can be called ngx api

location / {

    content_by_lua_file /usr/local/openresty/file/test.lua
    
}


#  file ：/usr/local/openresty/file/test.lua
hello gtlx

            

balancer_by_lua_block： The content processing phase executes , stay upstream Use in statement

 Grammar format ：balancer_by_lua_block {...}
* upstream The use of ip by balancer_by_lua_block The address set in 
*  Forbidden api：cosockets、light threads


upstream web-server {
    server  172.18.0.2   # Will ignore server Set up ip Address 

    balancer_by_lua_block {
        ...              # It's really used ip Address 
    }
}

                  

header_filter_by_lua_block： The response phase adds 、 Delete response header , stay http、server、location Set in

 Grammar format ：header_filter_by_lua_block {...}
*  Forbidden api：ngx.say()、ngx.redirect()、ngx.exec() etc. 

#  Add response header 
location {
    header_filter_by_lua_block {
        ngx.header.test="hello gtlx"
    }

    echo "hello"
}

           

body_filter_by_lua_block： In the response phase, modify the response body , stay http、server、location Set in

 Grammar format ：body_filter_by_lua_block {...}
*  Forbidden api：ngx.say()、ngx.redirect()、ngx.exec() etc. 

#  Convert the corresponding data to uppercase (ngx.arg[1] Get response data ,ngx.arg[2] Response terminator )
#  Output ：HELLO
location {
    body_filter_by_lua_block {
        ngx.arg[1] = string.upper(ngx.arg[1]);
    }

    echo "hello"
}

        

log_by_lua_block： Output log , Can be found in http、server、location Set in

 Grammar format ：log_filter_by_lua_block {...}
*  stay access_log Before execution , Will not replace the current access_log journal 
*  Forbidden api：ngx.say()、ngx.redirect()、ngx.exec() etc. 

location {
    log_filter_by_lua_block {
        ngx.log("hello gtlx")
    }

    echo "hello"
}