How do you log in your projects?

Fri Feb 11 16:11:27 EST 2022

On Wed, 9 Feb 2022 19:38:23 +0000, Martin Di Paola wrote:
>>> - On a line per line basis? on a function/method basis?
>> In general I prefer logging line by line instead per function.
>> It is easy to add a bunch of decorators to the functions and get the
> logs of all the program but I most of the time I end up with very
> confusing logs.
>> There are exceptions, yes, but I prefer the line by line where the log
> should explain what is doing the code.
>>>> - Which kind of variable contents do you write into your logfiles?
>>> - How do you decide, which kind of log message goes into which level?
>>> - How do you prevent logging cluttering your actual code?
>> These three comes to the same answer: I think on whom is going to read
> the logs.
>> If the logs are meant to be read by my users I log high level messages,
> specially before parts that can take a while (like the classic
> "Loading...").
>> If I log variables, those must be the ones set by the users so he/she
> can understand how he/she is controlling the behaviour of the program.
>> For exceptions I print the message but not the traceback. Across the
> code tag some important functions to put an extra message that will
> enhance the final message printed to the user.
>> https://github.com/byexamples/byexample/blob/master/byexample/
common.py#L192-L238
>> For example:
>> for example in examples:
> with enhance_exceptions(example, ...):
> foo()
>> So if an exception is raised by foo(), enhance_exceptions() will attach
> to it useful information for the user from the example variable.
>> In the main, then I do the pretty print
> https://github.com/byexamples/byexample/blob/master/byexample/
byexample.py#L17-L22
>> If the user of the logs is me or any other developer I write more
> debugging stuff.
>> My approach is to not log anything and when I have to debug something I
> use a debugger + some prints. When the issue is fixed I review which
> prints would be super useful and I turn them into logs and the rest is
> deleted.
>>> On Tue, Feb 08, 2022 at 09:40:07PM +0100, Marco Sulla wrote:
>>These are a lot of questions. I hope we're not off topic.
>>I don't know if mine are best practices. I can tell what I try to do.
>>>>On Tue, 8 Feb 2022 at 15:15, Lars Liedtke <liedtke at punkt.de> wrote:
>>> - On a line per line basis? on a function/method basis?
>>>>I usually log the start and end of functions. I could also log inside a
>>branch or in other parts of the function/method.
>>>>> - Do you use decorators to mark beginnings and ends of
>>> methods/functions in log files?
>>>>No, since I put the function parameters in the first log. But I think
>>that such a decorator it's not bad.
>>>>> - Which kind of variable contents do you write into your logfiles? Of
>>> course you shouldn't leak secrets...
>>>>Well, all the data that is useful to understand what the code is doing.
>>It's better to repeat the essential data to identify a specific call in
>>all the logs of the function, so if it is called simultaneously by more
>>clients you can distinguish them
>>>>> - How do you decide, which kind of log message goes into which level?
>>>>It depends on the importance, the verbosity and the occurrences of the
>>logs.
>>>>> - How do you prevent logging cluttering your actual code?
>>>>I have the opposite problem, I should log more. So I can't answer your
>>question.
>>--
>>https://mail.python.org/mailman/listinfo/python-list
In my current project I use the loggin module & write to a file
I log at info level for the entry & exit of each function/method
& scatter debug level logs for arease where I need to check data is as 
expected
I have also found Ansi colour codes usefull when skiming through the 
output
-- 
If an experiment works, something has gone wrong.