Re: [PATCH 12/14] doc-rst: add ABI documentation to the admin-guide book

[Jani Nikula <jani.nikula@linux.intel.com>]

On Fri, 21 Jun 2019, Mauro Carvalho Chehab <mchehab+samsung@kernel.org> wrote:
> Em Wed, 19 Jun 2019 13:37:39 -0300
> Mauro Carvalho Chehab <mchehab+samsung@kernel.org> escreveu:
>
>> Em Tue, 18 Jun 2019 11:47:32 +0300
>> Jani Nikula <jani.nikula@linux.intel.com> escreveu:
>> 
>> > On Mon, 17 Jun 2019, Mauro Carvalho Chehab <mchehab+samsung@kernel.org> wrote:  
>> > > Yeah, I guess it should be possible to do that. How a python script
>> > > can identify if it was called by Sphinx, or if it was called directly?    
>> > 
>> > if __name__ == '__main__':
>> > 	# run on the command-line, not imported  
>> 
>> Ok, when I have some spare time, I may try to convert one script
>> to python and see how it behaves. 
>
> Did a quick test here... 
>
> Probably I'm doing something wrong (as I'm a rookie with Python), but,
> in order to be able to use the same script as command line and as an Sphinx
> extension, everything that it is currently there should be "escaped"
> by an:
>
> 	if __name__ != '__main__':
>
> As event the class definition:
>
>     class KernelCmd(Directive):
>
> depends on:
>
> 	from docutils.parsers.rst import directives, Directive
>
> With is only required when one needs to parse ReST - e. g. only
> when the script runs as a Sphinx extension.
>
> If this is right, as we want a script that can run by command line
> to parse and search inside ABI files, at the end of the day, it will
> be a lot easier to maintain if the parser script is different from the
> Sphinx extension. 

Split it into two files, one has the nuts and bolts of parsing and has
the "if __name__ == '__main__':" bit to run on the command line, and the
other interfaces with Sphinx and imports the parser.

> If so, as the Sphinx extension script will need to call a parsing script
> anyway, it doesn't matter the language of the script with will be
> doing the ABI file parsing.

Calling the parser using an API will be easier to use, maintain and
extend than using pipes, with all the interleaved sideband information
to adjust line numbers and whatnot.

BR,
Jani.



>
> See the enclosing file. I didn't add anything from the ABI parsing
> script yet. It was just changed in order to not generate an error
> when trying to run it from command line.
>
>
> Thanks,
> Mauro
> #!/usr/bin/env python3
> # coding=utf-8
> # SPDX-License-Identifier: GPL-2.0
> #
> u"""
>     kernel-abi
>     ~~~~~~~~~~
>
>     Implementation of the ``kernel-abi`` reST-directive.
>
>     :copyright:  Copyright (C) 2016  Markus Heiser
>     :copyright:  Copyright (C) 2016-2019  Mauro Carvalho Chehab
>     :maintained-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
>     :license:    GPL Version 2, June 1991 see Linux/COPYING for details.
>
>     The ``kernel-abi`` (:py:class:`KernelCmd`) directive calls the
>     scripts/get_abi.pl script to parse the Kernel ABI files.
>
>     Overview of directive's argument and options.
>
>     .. code-block:: rst
>
>         .. kernel-abi:: <ABI directory location>
>             :debug:
>
>     The argument ``<ABI directory location>`` is required. It contains the
>     location of the ABI files to be parsed.
>
>     ``debug``
>       Inserts a code-block with the *raw* reST. Sometimes it is helpful to see
>       what reST is generated.
>
> """
>
> import codecs
> import os
> import subprocess
> import sys
>
> from os import path
>
> if __name__ != '__main__':
>     from docutils import nodes, statemachine
>     from docutils.statemachine import ViewList
>     from docutils.parsers.rst import directives, Directive
>     from docutils.utils.error_reporting import ErrorString
>
>     #
>     # AutodocReporter is only good up to Sphinx 1.7
>     #
>     import sphinx
>
>     Use_SSI = sphinx.__version__[:3] >= '1.7'
>     if Use_SSI:
>         from sphinx.util.docutils import switch_source_input
>     else:
>         from sphinx.ext.autodoc import AutodocReporter
>
> __version__  = '1.0'
>
> if __name__ != '__main__':
>     def setup(app):
>
>         app.add_directive("kernel-abi", KernelCmd)
>         return dict(
>             version = __version__
>             , parallel_read_safe = True
>             , parallel_write_safe = True
>         )
>
>     class KernelCmd(Directive):
>
>         u"""KernelABI (``kernel-abi``) directive"""
>
>         required_arguments = 1
>         optional_arguments = 2
>         has_content = False
>         final_argument_whitespace = True
>
>         option_spec = {
>             "debug"     : directives.flag,
>             "rst"       : directives.unchanged
>         }
>
>         def warn(self, message, **replace):
>             replace["fname"]   = self.state.document.current_source
>             replace["line_no"] = replace.get("line_no", self.lineno)
>             message = ("%(fname)s:%(line_no)s: [kernel-abi WARN] : " + message) % replace
>             self.state.document.settings.env.app.warn(message, prefix="")
>
>         def run(self):
>
>             doc = self.state.document
>             if not doc.settings.file_insertion_enabled:
>                 raise self.warning("docutils: file insertion disabled")
>
>             env = doc.settings.env
>             cwd = path.dirname(doc.current_source)
>             fname = self.arguments[0]
>
>             cmd = "get_abi.pl rest --dir "
>             cmd += fname
>
>             if 'rst' in self.options:
>                 cmd += " --rst-source"
>
>             srctree = path.abspath(os.environ["srctree"])
>
>             # extend PATH with $(srctree)/scripts
>             path_env = os.pathsep.join([
>                 srctree + os.sep + "scripts",
>                 os.environ["PATH"]
>             ])
>             shell_env = os.environ.copy()
>             shell_env["PATH"]    = path_env
>             shell_env["srctree"] = srctree
>
>             lines = self.runCmd(cmd, shell=True, cwd=cwd, env=shell_env)
>             nodeList = self.nestedParse(lines, self.arguments[0])
>             return nodeList
>
>         def runCmd(self, cmd, **kwargs):
>             u"""Run command ``cmd`` and return it's stdout as unicode."""
>
>             try:
>                 proc = subprocess.Popen(
>                     cmd
>                     , stdout = subprocess.PIPE
>                     , stderr = subprocess.PIPE
>                     , **kwargs
>                 )
>                 out, err = proc.communicate()
>
>                 out, err = codecs.decode(out, 'utf-8'), codecs.decode(err, 'utf-8')
>
>                 if proc.returncode != 0:
>                     raise self.severe(
>                         u"command '%s' failed with return code %d"
>                         % (cmd, proc.returncode)
>                     )
>             except OSError as exc:
>                 raise self.severe(u"problems with '%s' directive: %s."
>                                 % (self.name, ErrorString(exc)))
>             return out
>
>         def nestedParse(self, lines, fname):
>             content = ViewList()
>             node    = nodes.section()
>
>             if "debug" in self.options:
>                 code_block = "\n\n.. code-block:: rst\n    :linenos:\n"
>                 for l in lines.split("\n"):
>                     code_block += "\n    " + l
>                 lines = code_block + "\n\n"
>
>             for c, l in enumerate(lines.split("\n")):
>                 content.append(l, fname, c)
>
>             buf  = self.state.memo.title_styles, self.state.memo.section_level, self.state.memo.reporter
>
>             if Use_SSI:
>                 with switch_source_input(self.state, content):
>                     self.state.nested_parse(content, 0, node, match_titles=1)
>             else:
>                 self.state.memo.title_styles  = []
>                 self.state.memo.section_level = 0
>                 self.state.memo.reporter      = AutodocReporter(content, self.state.memo.reporter)
>                 try:
>                     self.state.nested_parse(content, 0, node, match_titles=1)
>                 finally:
>                     self.state.memo.title_styles, self.state.memo.section_level, self.state.memo.reporter = buf
>
>             return node.children

-- 
Jani Nikula, Intel Open Source Graphics Center