Re: [Tarantool-patches] [PATCH v7 10/11] log/lua: allow to specify logging level as a string

[Oleg Babin <olegrok@tarantool.org>]

Also. I've found that it's not allowed to set log level as string via 
box API:

```

tarantool> box.cfg{log_level = 'info'}
---
- error: 'Incorrect value for option ''log_level'': should be of type 
number'
...

```

But it could be easily fixed here: 
https://github.com/tarantool/tarantool/blob/master/src/box/lua/load_cfg.lua#L129

On 02/06/2020 01:25, Cyrill Gorcunov wrote:
> Allow to specify logging level as a string in log.cfg() call.
> 
> @TarantoolBot document
> Title: Module log
> 
> The `log.cfg({level='string'})` accepts not only number but
> symbolic repreentation of loglevels such as: `fatal`, `syserror`,
> `error`, `crit`, `warn`, `info`, `verbose` and `debug`.
> 
> Part-of #689
> 
> Suggested-by: Oleg Babin <olegrok@tarantool.org>
> Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
> ---
>   src/lua/log.lua              | 36 ++++++++++++++++++++++++++++++++++--
>   test/app-tap/logger.test.lua | 29 ++++++++++++++++++++++++++++-
>   2 files changed, 62 insertions(+), 3 deletions(-)
> 
> diff --git a/src/lua/log.lua b/src/lua/log.lua
> index dfdc326fe..3376932ff 100644
> --- a/src/lua/log.lua
> +++ b/src/lua/log.lua
> @@ -140,6 +140,26 @@ local function update_box_cfg(k)
>       end
>   end
>   
> +-- Logging levels symbolic representation.
> +local log_level_keys = {
> +    ['fatal']       = ffi.C.S_FATAL,
> +    ['syserror']    = ffi.C.S_SYSERROR,
> +    ['error']       = ffi.C.S_ERROR,
> +    ['crit']        = ffi.C.S_CRIT,
> +    ['warn']        = ffi.C.S_WARN,
> +    ['info']        = ffi.C.S_INFO,
> +    ['verbose']     = ffi.C.S_VERBOSE,
> +    ['debug']       = ffi.C.S_DEBUG,
> +}
> +
> +local function log_level_list()
> +    local keyset = {}
> +    for k in pairs(log_level_keys) do
> +        keyset[#keyset + 1] = k
> +    end
> +    return table.concat(keyset, ',')
> +end
> +
>   local function say(level, fmt, ...)
>       if ffi.C.log_level < level then
>           -- don't waste cycles on debug.getinfo()
> @@ -279,8 +299,20 @@ local function load_cfg(oldcfg, cfg)
>       end
>   
>       if cfg.level ~= nil then
> -        if type(cfg.level) ~= 'number' then
> -            error("log: 'level' option must be a number")
> +        if type(cfg.level) == 'number' then
> +            if cfg.level < ffi.C.S_FATAL or
> +                cfg.level > ffi.C.S_DEBUG then
> +                local m = "log: 'level' must be in range [%d;%d]"
> +                error(m:format(ffi.C.S_FATAL, ffi.C.S_DEBUG))
> +            end
> +        elseif type(cfg.level) == 'string' then
> +            if log_level_keys[cfg.level] == nil then
> +                local m = "log: 'level' must be one of [%s]"
> +                error(m:format(log_level_list()))
> +            end
> +            cfg.level = log_level_keys[cfg.level]
> +        else
> +            error("log: 'level' must be a number or string")
>           end
>       end
>   
> diff --git a/test/app-tap/logger.test.lua b/test/app-tap/logger.test.lua
> index c6f207908..557c31f1a 100755
> --- a/test/app-tap/logger.test.lua
> +++ b/test/app-tap/logger.test.lua
> @@ -1,7 +1,7 @@
>   #!/usr/bin/env tarantool
>   
>   local test = require('tap').test('log')
> -test:plan(34)
> +test:plan(44)
>   
>   -- gh-3946: Assertion failure when using log_format() before box.cfg()
>   local log = require('log')
> @@ -60,6 +60,33 @@ log.cfg({format='plain', level=5})
>   test:is(box.cfg.log_format, 'plain', 'box sees plain format')
>   test:is(box.cfg.log_level, 5, 'box sees level change')
>   
> +-- Test symbolic names for loglevels
> +log.cfg({level='fatal'})
> +test:ok(log.cfg.level == 0 and box.cfg.log_level == 0, 'both sees fatal')
> +log.cfg({level='syserror'})
> +test:ok(log.cfg.level == 1 and box.cfg.log_level == 1, 'both sees fatal')
> +log.cfg({level='error'})
> +test:ok(log.cfg.level == 2 and box.cfg.log_level == 2, 'both sees fatal')
> +log.cfg({level='crit'})
> +test:ok(log.cfg.level == 3 and box.cfg.log_level == 3, 'both sees fatal')
> +log.cfg({level='warn'})
> +test:ok(log.cfg.level == 4 and box.cfg.log_level == 4, 'both sees fatal')
> +log.cfg({level='info'})
> +test:ok(log.cfg.level == 5 and box.cfg.log_level == 5, 'both sees fatal')
> +log.cfg({level='verbose'})
> +test:ok(log.cfg.level == 6 and box.cfg.log_level == 6, 'both sees fatal')
> +log.cfg({level='debug'})
> +test:ok(log.cfg.level == 7 and box.cfg.log_level == 7, 'both sees fatal')
> +
> +_,err = pcall(log, {level = -1})
> +test:ok(err ~= nil, 'level = -1 error')
> +
> +_,err = pcall(log, {level = 'unknown'})
> +test:ok(err ~= nil, "level = 'unknown' error")
> +
> +-- restore to info for next tests
> +log.cfg({level='info'})
> +
>   --
>   -- Check that Tarantool creates ADMIN session for #! script
>   --
>