python-peps/docutils/core.py

326 lines
14 KiB
Python

# Authors: David Goodger
# Contact: goodger@users.sourceforge.net
# Revision: $Revision$
# Date: $Date$
# Copyright: This module has been placed in the public domain.
"""
Calling the ``publish_*`` convenience functions (or instantiating a
`Publisher` object) with component names will result in default
behavior. For custom behavior (setting component options), create
custom component objects first, and pass *them* to
``publish_*``/`Publisher`.
"""
__docformat__ = 'reStructuredText'
import sys
from docutils import Component
from docutils import frontend, io, readers, parsers, writers
from docutils.frontend import OptionParser, ConfigParser
class Publisher:
"""
A facade encapsulating the high-level logic of a Docutils system.
"""
def __init__(self, reader=None, parser=None, writer=None,
source=None, source_class=io.FileInput,
destination=None, destination_class=io.FileOutput,
settings=None):
"""
Initial setup. If any of `reader`, `parser`, or `writer` are not
specified, the corresponding ``set_...`` method should be called with
a component name (`set_reader` sets the parser as well).
"""
self.reader = reader
"""A `readers.Reader` instance."""
self.parser = parser
"""A `parsers.Parser` instance."""
self.writer = writer
"""A `writers.Writer` instance."""
self.source = source
"""The source of input data, an `io.Input` instance."""
self.source_class = source_class
"""The class for dynamically created source objects."""
self.destination = destination
"""The destination for docutils output, an `io.Output` instance."""
self.destination_class = destination_class
"""The class for dynamically created destination objects."""
self.settings = settings
"""An object containing Docutils settings as instance attributes.
Set by `self.process_command_line()` or `self.get_settings()`."""
def set_reader(self, reader_name, parser, parser_name):
"""Set `self.reader` by name."""
reader_class = readers.get_reader_class(reader_name)
self.reader = reader_class(parser, parser_name)
self.parser = self.reader.parser
def set_writer(self, writer_name):
"""Set `self.writer` by name."""
writer_class = writers.get_writer_class(writer_name)
self.writer = writer_class()
def set_components(self, reader_name, parser_name, writer_name):
if self.reader is None:
self.set_reader(reader_name, self.parser, parser_name)
if self.parser is None:
if self.reader.parser is None:
self.reader.set_parser(parser_name)
self.parser = self.reader.parser
if self.writer is None:
self.set_writer(writer_name)
def setup_option_parser(self, usage=None, description=None,
settings_spec=None, **defaults):
#@@@ Add self.source & self.destination to components in future?
option_parser = OptionParser(
components=(settings_spec, self.parser, self.reader, self.writer),
usage=usage, description=description)
config = ConfigParser()
config.read_standard_files()
config_settings = config.get_section('options')
frontend.make_paths_absolute(config_settings,
option_parser.relative_path_settings)
defaults.update(config_settings)
option_parser.set_defaults(**defaults)
return option_parser
def get_settings(self, usage=None, description=None,
settings_spec=None, **defaults):
"""
Set and return default settings (overrides in `defaults` keyword
argument).
Set components first (`self.set_reader` & `self.set_writer`).
Explicitly setting `self.settings` disables command line option
processing from `self.publish()`.
"""
option_parser = self.setup_option_parser(usage, description,
settings_spec, **defaults)
self.settings = option_parser.get_default_values()
return self.settings
def process_command_line(self, argv=None, usage=None, description=None,
settings_spec=None, **defaults):
"""
Pass an empty list to `argv` to avoid reading `sys.argv` (the
default).
Set components first (`self.set_reader` & `self.set_writer`).
"""
option_parser = self.setup_option_parser(usage, description,
settings_spec, **defaults)
if argv is None:
argv = sys.argv[1:]
self.settings = option_parser.parse_args(argv)
def set_io(self, source_path=None, destination_path=None):
if self.source is None:
self.set_source(source_path=source_path)
if self.destination is None:
self.set_destination(destination_path=destination_path)
def set_source(self, source=None, source_path=None):
if source_path is None:
source_path = self.settings._source
else:
self.settings._source = source_path
self.source = self.source_class(self.settings, source=source,
source_path=source_path)
def set_destination(self, destination=None, destination_path=None):
if destination_path is None:
destination_path = self.settings._destination
else:
self.settings._destination = destination_path
self.destination = self.destination_class(
self.settings, destination=destination,
destination_path=destination_path)
def apply_transforms(self, document):
document.transformer.populate_from_components(
(self.source, self.reader, self.reader.parser, self.writer,
self.destination))
document.transformer.apply_transforms()
def publish(self, argv=None, usage=None, description=None,
settings_spec=None, settings_overrides=None):
"""
Process command line options and arguments (if `self.settings` not
already set), run `self.reader` and then `self.writer`. Return
`self.writer`'s output.
"""
if self.settings is None:
self.process_command_line(argv, usage, description, settings_spec,
**(settings_overrides or {}))
elif settings_overrides:
self.settings._update(settings_overrides, 'loose')
self.set_io()
document = self.reader.read(self.source, self.parser, self.settings)
self.apply_transforms(document)
output = self.writer.write(document, self.destination)
if self.settings.dump_settings:
from pprint import pformat
print >>sys.stderr, '\n::: Runtime settings:'
print >>sys.stderr, pformat(self.settings.__dict__)
if self.settings.dump_internals:
from pprint import pformat
print >>sys.stderr, '\n::: Document internals:'
print >>sys.stderr, pformat(document.__dict__)
if self.settings.dump_transforms:
from pprint import pformat
print >>sys.stderr, '\n::: Transforms applied:'
print >>sys.stderr, pformat(document.transformer.applied)
if self.settings.dump_pseudo_xml:
print >>sys.stderr, '\n::: Pseudo-XML:'
print >>sys.stderr, document.pformat().encode(
'raw_unicode_escape')
return output
default_usage = '%prog [options] [<source> [<destination>]]'
default_description = ('Reads from <source> (default is stdin) and writes to '
'<destination> (default is stdout).')
def publish_cmdline(reader=None, reader_name='standalone',
parser=None, parser_name='restructuredtext',
writer=None, writer_name='pseudoxml',
settings=None, settings_spec=None,
settings_overrides=None, argv=None,
usage=default_usage, description=default_description):
"""
Set up & run a `Publisher`. For command-line front ends.
Parameters:
- `reader`: A `docutils.readers.Reader` object.
- `reader_name`: Name or alias of the Reader class to be instantiated if
no `reader` supplied.
- `parser`: A `docutils.parsers.Parser` object.
- `parser_name`: Name or alias of the Parser class to be instantiated if
no `parser` supplied.
- `writer`: A `docutils.writers.Writer` object.
- `writer_name`: Name or alias of the Writer class to be instantiated if
no `writer` supplied.
- `settings`: Runtime settings object.
- `settings_spec`: Extra settings specification; a `docutils.SettingsSpec`
subclass. Used only if no `settings` specified.
- `settings_overrides`: A dictionary containing program-specific overrides
of component settings.
- `argv`: Command-line argument list to use instead of ``sys.argv[1:]``.
- `usage`: Usage string, output if there's a problem parsing the command
line.
- `description`: Program description, output for the "--help" option
(along with command-line option descriptions).
"""
pub = Publisher(reader, parser, writer, settings=settings)
pub.set_components(reader_name, parser_name, writer_name)
pub.publish(argv, usage, description, settings_spec, settings_overrides)
def publish_file(source=None, source_path=None,
destination=None, destination_path=None,
reader=None, reader_name='standalone',
parser=None, parser_name='restructuredtext',
writer=None, writer_name='pseudoxml',
settings=None, settings_spec=None, settings_overrides=None):
"""
Set up & run a `Publisher`. For programmatic use with file-like I/O.
Parameters:
- `source`: A file-like object (must have "read" and "close" methods).
- `source_path`: Path to the input file. Opened if no `source` supplied.
If neither `source` nor `source_path` are supplied, `sys.stdin` is used.
- `destination`: A file-like object (must have "write" and "close"
methods).
- `destination_path`: Path to the input file. Opened if no `destination`
supplied. If neither `destination` nor `destination_path` are supplied,
`sys.stdout` is used.
- `reader`: A `docutils.readers.Reader` object.
- `reader_name`: Name or alias of the Reader class to be instantiated if
no `reader` supplied.
- `parser`: A `docutils.parsers.Parser` object.
- `parser_name`: Name or alias of the Parser class to be instantiated if
no `parser` supplied.
- `writer`: A `docutils.writers.Writer` object.
- `writer_name`: Name or alias of the Writer class to be instantiated if
no `writer` supplied.
- `settings`: Runtime settings object.
- `settings_spec`: Extra settings specification; a `docutils.SettingsSpec`
subclass. Used only if no `settings` specified.
- `settings_overrides`: A dictionary containing program-specific overrides
of component settings.
"""
pub = Publisher(reader, parser, writer, settings=settings)
pub.set_components(reader_name, parser_name, writer_name)
if settings is None:
settings = pub.get_settings(settings_spec=settings_spec)
if settings_overrides:
settings._update(settings_overrides, 'loose')
pub.set_source(source, source_path)
pub.set_destination(destination, destination_path)
pub.publish()
def publish_string(source, source_path=None, destination_path=None,
reader=None, reader_name='standalone',
parser=None, parser_name='restructuredtext',
writer=None, writer_name='pseudoxml',
settings=None, settings_spec=None,
settings_overrides=None):
"""
Set up & run a `Publisher`, and return the string output.
For programmatic use with string I/O.
For encoded string output, be sure to set the "output_encoding" setting to
the desired encoding. Set it to "unicode" for unencoded Unicode string
output.
Parameters:
- `source`: An input string; required. This can be an encoded 8-bit
string (set the "input_encoding" setting to the correct encoding) or a
Unicode string (set the "input_encoding" setting to "unicode").
- `source_path`: Path to the file or object that produced `source`;
optional. Only used for diagnostic output.
- `destination_path`: Path to the file or object which will receive the
output; optional. Used for determining relative paths (stylesheets,
source links, etc.).
- `reader`: A `docutils.readers.Reader` object.
- `reader_name`: Name or alias of the Reader class to be instantiated if
no `reader` supplied.
- `parser`: A `docutils.parsers.Parser` object.
- `parser_name`: Name or alias of the Parser class to be instantiated if
no `parser` supplied.
- `writer`: A `docutils.writers.Writer` object.
- `writer_name`: Name or alias of the Writer class to be instantiated if
no `writer` supplied.
- `settings`: Runtime settings object.
- `settings_spec`: Extra settings specification; a `docutils.SettingsSpec`
subclass. Used only if no `settings` specified.
- `settings_overrides`: A dictionary containing program-specific overrides
of component settings.
"""
pub = Publisher(reader, parser, writer, settings=settings,
source_class=io.StringInput,
destination_class=io.StringOutput)
pub.set_components(reader_name, parser_name, writer_name)
if settings is None:
settings = pub.get_settings(settings_spec=settings_spec)
if settings_overrides:
settings._update(settings_overrides, 'loose')
pub.set_source(source, source_path)
pub.set_destination(destination_path=destination_path)
return pub.publish()