apisix lua插件开发

1. 怎么定义ngx自定义变量 ngx.var.custom_var

nginx_config: # config for render the template to generate nginx.conf
...
...
...
  http_server_configuration_snippet: |
    set $custom_key "test";
    set $custom_key1 "tetet";
    # Add custom Nginx http server configuration to nginx.conf.
    # The configuration should be well indented!

2. 自定义内存变量 lua_shared_dict

nginx_config: # config for render the template to generate nginx.conf
  http:
     custom_lua_shared_dict:       # add custom shared cache to nginx.conf
        customDb: 10m

3. 刷新 nginx 共享内存

local function ngx_db_flush()
    -- 刷新共享字典的内存
    local ok, err = customDb:flush_all()
    if err then
        core.log.error(err)
    end
    local ok, err = customDb:flush_expired()
    if err then
        core.log.error(err)
    end
end