Re: [tarantool-patches] [PATCH] log: add missing assert into log_set_format()

[Vladimir Davydov <vdavydov.dev@gmail.com>]

On Sat, Mar 02, 2019 at 08:29:46PM +0300, Roman Khabibov wrote:
> Add missing condition for json format into assert in log_set_format() function.
> 
> Closes #3946
> ---
> 
> Branch: https://github.com/tarantool/tarantool/tree/romanhabibov/gh-3946-log-assert/test
> Issue: https://github.com/tarantool/tarantool/issues/3946
> 
>  src/lib/core/say.c           | 3 ++-
>  test/app-tap/logger.test.lua | 6 +++++-
>  2 files changed, 7 insertions(+), 2 deletions(-)
> 
> diff --git a/src/lib/core/say.c b/src/lib/core/say.c
> index 50ee55692..758b1c234 100644
> --- a/src/lib/core/say.c
> +++ b/src/lib/core/say.c
> @@ -170,7 +170,8 @@ log_set_level(struct log *log, enum say_level level)
>  void
>  log_set_format(struct log *log, log_format_func_t format_func)
>  {
> -	assert(format_func == say_format_plain ||
> +	assert(format_func == say_format_json ||
> +	       format_func == say_format_plain ||
>  	       log->type == SAY_LOGGER_STDERR ||
>  	       log->type == SAY_LOGGER_PIPE || log->type == SAY_LOGGER_FILE);

The assertion is meaningless after this change. At least the log->type
check. I guess the idea was to check that json format isn't used in
conjunction with syslog.

Also, there's another similar assertion failure that I think should be
fixed in the scope of this patch:

box.cfg{log = 'syslog:identity=tarantool'}
require('log').log_format('json')

tarantool: /home/vlad/src/tarantool/src/lib/core/say.c:195: say_set_log_format: Assertion `log_default->type != SAY_LOGGER_SYSLOG' failed.

>  
> diff --git a/test/app-tap/logger.test.lua b/test/app-tap/logger.test.lua
> index 0c11702c8..4e18d53e9 100755
> --- a/test/app-tap/logger.test.lua
> +++ b/test/app-tap/logger.test.lua
> @@ -1,13 +1,17 @@
>  #!/usr/bin/env tarantool
>  
>  local test = require('tap').test('log')
> -test:plan(24)
> +test:plan(25)
>  
>  --
>  -- Check that Tarantool creates ADMIN session for #! script
>  --
>  local filename = "1.log"
>  local message = "Hello, World!"
> +
> +jlog = require('log')
> +test:ok(jlog.log_format("json") == nil, "no assertions")
> +

Squeezing a test case like this, without a proper comment, looks bad -
it seems that the comment above is related to it although it isn't.
Also, jlog is a bad name. If you don't want to pollute the namespace,
you can get along without it:

	require('log').log_format('json')

>  box.cfg{
>      log=filename,
>      memtx_memory=107374182,