Re: [boost] [log] init_from_settings - problem with applying format and filter

Subject: Re: [boost] [log] init_from_settings - problem with applying format and filter
From: Petrovskiy Yuriy (yuriy.petrovskiy_at_[hidden])
Date: 2011-07-04 11:08:08

2011/7/4 Andrey Semashev <andrey.semashev_at_[hidden]>

> On 07/04/2011 03:47 PM, Petrovskiy Yuriy wrote:
>
>  The questions are:
>> - How to configure  severity_logger using    init_from_settings() to get
>> the
>> custom severity levels in the log?
>>
>
> You have to register any user-defined attribute value types with the
> library in order to be able to use it with filter and format parsers. This
> includes your severity level enum.
>
> If your type supports insertion and extraction from stream, you can do it
> by these two lines:
>
>  boost::log::register_simple_formatter_factory< logMessageSeverityLevels
> >("Severity");
>  boost::log::register_simple_filter_factory< logMessageSeverityLevels
> >("Severity");
>  ...

Thank you, this worked good.

>
>  - Why "Format" variables do not work? (and why  %TimeStamp% starts to work
>> if using BOOST_LOG_TRIVIAL for output)?
>>
>
> Because you didn't add the TimeStamp attribute to the core. Your log
> records don't contain time stamps and thus you don't see them in the output.
>
How to add it correctly?

>  - What should be done to make logger append to log (not overwrite)?
>>
>
> You should specify open_mode parameter when creating the text file sink,
> like this:
>
>  init_log_to_file(
>    keywords::file_name = "my.log",
>    keywords::open_mode = std::ios::app);
>
> You can also pass this option to the backend constructor, if you create it
> explicitly.

Is it possible to do with  init_from_settings? I found no corresponding
option in documentation. I think it is important feature to be configured
through config file|settings.

>  - Is it possible to log file and line using format variables (only to
>> file)?
>>
>
>  You mean file and line where a log record is made? You can do this, but
> only if you add file name and line number as attributes to each record. You
> can wrap in the logging macros to do this automatically.
>
Is there any standard solution for this?

Thank you for guidance.
Yuriy Petrovskiy