Use python logging to populate junit-xml without showing up in console

[redlars]

How can logging information from pytest be piped to junit-xml without being shown in console output? Used Windows 10 to test this code.

We have the following simple unittest:

import logging
import unittest 
class fixture(unittest.TestCase):

def test_log(self):
   logging.basicConfig()
   logger = logging.getLogger(__name__)
   logger.info("Hello from inside a test")

if __name__ == '__main__':
    unittest.main()

The unittest is invoked as shown below, notice that diagnostics info message is included in console output. This is obviously a simple example but in a scenario with many tests and logging messages the console will quickly become very messy. We would therefore prefer that logging messages are not displayed in console and only show in the junit-xml file. We not be able to configure this setup yet.

py -m pytest test_1.py -v --capture=fd --junit-xml output.xml
========================== test session starts==================================
platform win32 -- Python 3.9.4, pytest-6.2.3, py-1.10.0, pluggy-0.13.1 -- 
C:\Users\JohnDoe\AppData\Local\Programs\Python\Python39\python.exe
cachedir: .pytest_cache
rootdir: C:\work\pytest_logging, configfile: pytest.ini
collected 1 item

test_1.py::fixture::test_log
---------------------------------- live log call ----------------------------------------------------------------------
20:09:03:INFO:Hello from inside a test
PASSED

-------------------------------- generated xml file: C:\work\pytest_logging\output.xml ---------------------------
======================== 1 passed in 0.03s ===================================   

The pytest.ini file looks like this

[pytest]
log_cli = true
log_cli_level = INFO
log_cli_format = %(asctime)s:%(levelname)s:%(message)s
junit_logging=log

The junit-xml file looks like this;

<testsuites>
 <testsuite name="pytest" errors="0" failures="0" skipped="0" tests="1" time="0.027" timestamp="2021-04-15T20:09:03.216546" hostname="myhost">
   <testcase classname="test_1.fixture" name="test_log" time="0.001">
    <system-out>--------------------------------- Captured Log ---------------------------------
#x1B[32mINFO    #x1B[0m test_1:test_1.py:9 Hello from inside a test
 --------------------------------- Captured Out ---------------------------------
    </system-out>
    <system-err>--------------------------------- Captured Err ---------------------------------
    </system-err>
  </testcase>
 </testsuite>
</testsuites>

A second tiny question, does pytest allow formatting the message that is displayed in junit-xml? The current text is a bit verbose and contains what I am guessing is color values for parts of the text.

[redlars]

Appreciate any input on this matter.

[nicoddemus]

Hi @redlars,

See if --show-capture can help you out:

  --show-capture={no,stdout,stderr,log,all}
    Controls how captured stdout/stderr/log is shown on failed tests. Default is 'all'.

[redlars]

Hi @nicoddemus,

Appreciate your input.

The argument did not control the console output from logging.info("...").
The argument did control writing directly to stdout or stderr (see code below) but only when test failed.

sys.stdout.write('Write some text\n\n\n')