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

[Cyrill Gorcunov <gorcunov@gmail.com>]

Since we're going to implement early setup of
logging module we need both.

Part-of #689

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
---
 src/box/lua/load_cfg.lua | 21 +++++++++++++++------
 src/lua/log.lua          | 37 ++++++++++++++++++++++++++++++++++++-
 2 files changed, 51 insertions(+), 7 deletions(-)

diff --git a/src/box/lua/load_cfg.lua b/src/box/lua/load_cfg.lua
index 5d818addf..9aef12840 100644
--- a/src/box/lua/load_cfg.lua
+++ b/src/box/lua/load_cfg.lua
@@ -1,4 +1,6 @@
 -- load_cfg.lua - internal file
+--
+-- vim: ts=4 sw=4 et
 
 local log = require('log')
 local json = require('json')
@@ -59,10 +61,6 @@ local default_cfg = {
     vinyl_range_size          = nil, -- set automatically
     vinyl_page_size           = 8 * 1024,
     vinyl_bloom_fpr           = 0.05,
-    log                 = nil,
-    log_nonblock        = nil,
-    log_level           = 5,
-    log_format          = "plain",
     io_collect_interval = nil,
     readahead           = 16320,
     snap_io_rate_limit  = nil, -- no limit
@@ -233,8 +231,8 @@ end
 local dynamic_cfg = {
     listen                  = private.cfg_set_listen,
     replication             = private.cfg_set_replication,
-    log_level               = private.cfg_set_log_level,
-    log_format              = private.cfg_set_log_format,
+    log_level               = log.box_api.set_log_level,
+    log_format              = log.box_api.set_log_format,
     io_collect_interval     = private.cfg_set_io_collect_interval,
     readahead               = private.cfg_set_readahead,
     too_long_threshold      = private.cfg_set_too_long_threshold,
@@ -470,6 +468,16 @@ local function apply_default_cfg(cfg, default_cfg)
     end
 end
 
+local function apply_default_modules_cfg(cfg)
+    --
+    -- logging
+    for k,v in pairs(log.box_api.cfg) do
+        if cfg[k] == nil then
+            cfg[k] = v
+        end
+    end
+end
+
 -- Return true if two configurations are equivalent.
 local function compare_cfg(cfg1, cfg2)
     if type(cfg1) ~= type(cfg2) then
@@ -554,6 +562,7 @@ local function load_cfg(cfg)
     cfg = upgrade_cfg(cfg, translate_cfg)
     cfg = prepare_cfg(cfg, default_cfg, template_cfg, modify_cfg)
     apply_default_cfg(cfg, default_cfg);
+    apply_default_modules_cfg(cfg)
     -- Save new box.cfg
     box.cfg = cfg
     if not pcall(private.cfg_check)  then
diff --git a/src/lua/log.lua b/src/lua/log.lua
index 4b078d598..ce546f21e 100644
--- a/src/lua/log.lua
+++ b/src/lua/log.lua
@@ -97,6 +97,22 @@ local fmt_str2num = {
     ["json"]            = ffi.C.SF_JSON,
 }
 
+--
+-- Default options. The keys are part of
+-- user API, so change with caution.
+local default_cfg = {
+    log             = nil,
+    log_nonblock    = nil,
+    log_level       = S_INFO,
+    log_format      = fmt_num2str[ffi.C.SF_PLAIN],
+}
+
+local log_cfg = setmetatable(default_cfg, {
+    __newindex = function()
+        error('log: Attempt to modify a read-only table')
+    end,
+})
+
 local function say(level, fmt, ...)
     if ffi.C.log_level < level then
         -- don't waste cycles on debug.getinfo()
@@ -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)
 end
 
 local function log_format(name)
@@ -170,6 +187,7 @@ local function log_format(name)
     else
         ffi.C.say_set_log_format(ffi.C.SF_PLAIN)
     end
+    rawset(log_cfg, 'log_format', name)
 end
 
 local function log_pid()
@@ -197,9 +215,26 @@ local log = {
     pid = log_pid,
     level = log_level,
     log_format = log_format,
+    --
+    -- Internal API to box module, not for users,
+    -- names can be changed.
+    box_api = {
+        cfg = log_cfg,
+        set_log_level = function()
+            log_level(box.cfg.log_level)
+        end,
+        set_log_format = function()
+            log_format(box.cfg.log_format)
+        end,
+    },
 }
 
 setmetatable(log, {
+    __serialize = function(self)
+        local res = table.copy(self)
+        res.box_api = nil
+        return setmetatable(res, {})
+    end,
     __index = compat_v16;
 })
 
-- 
2.26.2