Re: [Tarantool-patches] [PATCH v4 6/8] lua/log: use log module settings inside box.cfg

[Cyrill Gorcunov <gorcunov@gmail.com>]

On Thu, May 28, 2020 at 08:07:02PM +0300, lvasiliev wrote:
> > +local function apply_default_modules_cfg(cfg)
> 
> Looks like apply_default_cfg(cfg, log.box_api.cfg).
> Can we avoid code duplication?

The problem is keys naming. The module may have own mapping.
For example in my latest version we use variables without
log_ prefix but for box module sake we provide a map

log.lua
=======

-- Name mapping from box to log module.
-- Make sure all required fields are covered!
local log2box_keys = {
    ['log']         = 'log',
    ['nonblock']    = 'log_nonblock',
    ['level']       = 'log_level',
    ['format']      = 'log_format',
}

-- Apply defaut config to the box module
local function box_cfg_apply_default(box_cfg)
    for k, v in pairs(log_cfg) do
        if box_cfg[log2box_keys[k]] == nil then
            box_cfg[log2box_keys[k]] = v
        end
    end
end

load_cfg.lua
============

-- Fetch default settings from modules.
local function apply_default_modules_cfg(cfg)
    log.box_api.cfg_apply_default(cfg)
end

This isolate module specifics from box variables as
it should be I believe.

> 
> > +    --
> > +    -- logging
> > +    for k,v in pairs(log.box_api.cfg) do
> 
> Add a space before v.

already reworked, thanks!

> > @@ -146,7 +162,8 @@ local function log_rotate()
> >   end
> >   local function log_level(level)
> > -    return ffi.C.say_set_log_level(level)
> > +    ffi.C.say_set_log_level(level)
> > +    rawset(log_cfg, 'log_level', level)
> 
> Maybe I'm wrong, but seems like after that change the ffi.C.log_level
> is deprecated (log_cfg.log_level can be used instead). But now you
> keep 'level' in two places (ffi.C.log_level and log_cfg.log_level).

Not sure I follow here. You mean to drop their usage in Lua's
"function say()" in this module?

> >   setmetatable(log, {
> > +    __serialize = function(self)
> 
> Can you add a test on __serizlize?

Good point, will do.