[Freeipa-devel] [PATCH 25] Improve error logging for Dogtag subsystem installation

[Petr Spacek]

On 2.12.2015 12:51, Christian Heimes wrote:
> On 2015-12-02 08:37, Petr Spacek wrote:
>> On 1.12.2015 18:42, Christian Heimes wrote:
>>> From 33be1f56a64e53d261a1058c4606a7e48c0aac52 Mon Sep 17 00:00:00 2001
>>> From: Christian Heimes <cheimes at redhat.com>
>>> Date: Tue, 1 Dec 2015 15:49:53 +0100
>>> Subject: [PATCH 25] Improve error logging for Dogtag subsystem installation
>>>
>>> In the case of a failed installation or uninstallation of a Dogtag
>>> subsystem, the error output of pkispawn / pkidestroyed are now shown to
>>> the user. It makes it more obvious what went wrong and makes it easier
>>> to debug a problem.
>>>
>>> The error handler also attempts to get the full name of the installation
>>> / uninstallation log file from stdout. pkispawn and pkidestroy print the
>>> absolute name as 'Log file: /path/to/file.log'. The user no longer has
>>> to guess the right log file.
>>>
>>> Example:
>>>   [1/8]: configuring KRA instance
>>> Failed to configure KRA instance: Command ''/usr/sbin/pkispawn' '-s'
>>> 'KRA' '-f' '/tmp/tmp1UpbwF'' returned non-zero exit status 1
>>> pkispawn    : ERROR    ....... PKI subsystem 'KRA' for instance
>>> 'pki-tomcat' already exists!
>>> See the installation logs and the following files/directories for more
>>> information:
>>>   /var/log/pki/pki-tomcat
>>>   /var/log/pki/pki-kra-spawn.20151201151735.log
>>>   [error] RuntimeError: KRA configuration failed.
>>>
>>> The patch also changes a couple of modules that were using
>>> the CalledProcessError exception object from subprocess instead of
>>> ipautil.
>>
>> I'm wondering if ipautil.run() can log stdout and stderr on log level ERROR
>> when return code is non-zero (and log on level DEBUG as usual when return code
>> is zero).
>>
>> IMHO it would be nicer, universal, and does not require any changes in places
>> calling ipautil.run().
> 
> I think it's a bit confusing to print out stdout and stderr, because
> both streams are captured separately. The output is missing its
> chronological order. subprocess can capture stdout and stderr in the
> same stream, but then we can't distinguish between output and error
> output...

I do not think it is a problem if these two are clearly marked as such:
standard output: %s (if non-empty)
stanrard error output: %s (if non-empty)

> In case of Dogtag stderr contains the relevant error message. In order
> to understand the events, that lead to the particular error, a user has
> to read the log file anyway -- unless you run pkispawn with '-vv' for
> extra verbosity. But then you get pages over pages of debug output on
> *stderr*. It's not helpful either.

Sure, I was not talking about that :-)

-- 
Petr^2 Spacek