log: consume TSS logging and feed into python logging module

[joholl]

Remove the TSS logging to stderr. Instead, have the TSS log to a pipe. Read the pipe and feed the logging records into the python logging framework.

Example:

import logging

from test.TSS2_BaseTest import TpmSimulator

from tpm2_pytss import FAPI, FapiConfig
from tpm2_pytss.log import tss_loggers

# highlight using ANSI color codes
green = "\x1b[32m"
yellow = "\x1b[93m"
red = "\x1b[31"
blue = "\x1b[34m"
cyan = "\x1b[96m"
light_grey = "\x1b[37m"
reset = "\x1b[0m"

# setup logging
root_logger = logging.getLogger()
root_logger.setLevel(logging.NOTSET)
handler = logging.StreamHandler()
formatter = logging.Formatter(
    f"{light_grey}[%(levelname)s]{reset} {blue}%(pathname)s:%(lineno)d{reset} - {cyan}%(name)s {yellow}%(message)s{reset}",
    "%Y-%m-%d %H:%M:%S",
)
handler.setFormatter(formatter)
root_logger.addHandler(handler)

# set some TSS log levels as an example
for _module, logger in tss_loggers.items():
    logger.setLevel(logging.WARNING)
logging.getLogger("TSS.fapijson").setLevel(logging.DEBUG)

if __name__ == "__main__":
    tpm = TpmSimulator.getSimulator()
    tpm.start()

    with FapiConfig(
        temp_dirs=True, tcti=tpm.tcti_name_conf, ek_cert_less="yes"
    ) as fapi_config:
        with FAPI() as fapi:
            fapi.provision()

            fapi.create_key(path=f"/{fapi.config.profile_name}/HS/SRK/key_123")

            # provoke error logs
            fapi.create_key(
                path=f"/{fapi.config.profile_name}/HS/SRK/key_123", exists_ok=True
            )

    tpm.close()

Fixes #49.

[codecov]

Codecov Report

Merging #164 (ec28137) into master (07a92e9) will decrease coverage by 0.76%.
The diff coverage is 53.24%.

❗ Current head ec28137 differs from pull request most recent head 9868644. Consider uploading reports for the commit 9868644 to get more accurate results

@@            Coverage Diff             @@
##           master     #164      +/-   ##
==========================================
- Coverage   87.81%   87.04%   -0.77%     
==========================================
  Files          13       14       +1     
  Lines        3382     3459      +77     
  Branches      318      330      +12     
==========================================
+ Hits         2970     3011      +41     
- Misses        277      306      +29     
- Partials      135      142       +7     

Impacted Files	Coverage Δ
tpm2_pytss/log.py	52.63% <52.63%> (ø)
tpm2_pytss/__init__.py	100.00% <100.00%> (ø)

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[lgtm-com]

This pull request introduces 1 alert when merging ec28137 into 07a92e9 - view on LGTM.com

new alerts:

• 1 for Unused local variable

[lgtm-com]

This pull request introduces 1 alert when merging 9868644 into 07a92e9 - view on LGTM.com

new alerts:

• 1 for Unused local variable

[williamcroberts]

#49 was for logs needed within the Python bindings, I never really expected to grab the TSS log errors from stderr from the underlying C library.

It would be nicer if the C libraries had a setlog function where we could specify a callback into the Python code to decide what to do with the log over spinning up a Thread to consume stderr and filter.

[joholl]

Of course, why didn't I think about that? I agree, a C callback would be much more elegant. I'd really like to see that in the release!

Closing this for now. I'll work on this some more when I find the time.