##// END OF EJS Templates
Reset the interactive namespace __warningregistry__ before executing code...
Reset the interactive namespace __warningregistry__ before executing code Fixes #6611. Idea: Right now, people often don't see important warnings when running code in IPython, because (to a first approximation) any given warning will only issue once per session. Blink and you'll miss it! This is a very common contributor to confused emails to numpy-discussion. E.g.: In [5]: 1 / my_array_with_random_contents /home/njs/.user-python2.7-64bit-3/bin/ipython:1: RuntimeWarning: divide by zero encountered in divide #!/home/njs/.user-python2.7-64bit-3/bin/python Out[5]: array([ 1.77073316, -2.29765021, -2.01800811, ..., 1.13871243, -1.08302964, -8.6185091 ]) Oo, right, guess I gotta be careful of those zeros -- thanks, numpy, for giving me that warning! A few days later: In [592]: 1 / some_other_array Out[592]: array([ 3.07735763, 0.50769289, 0.83984078, ..., -0.67563917, -0.85736257, -1.36511271]) Oops, it turns out that this array had a zero in it too, and that's going to bite me later. But no warning this time! The effect of this commit is to make it so that warnings triggered by the code in cell 5 do *not* suppress warnings triggered by the code in cell 592. Note that this only applies to warnings triggered *directly* by code entered interactively -- if somepkg.foo() calls anotherpkg.bad_func() which issues a warning, then this warning will still only be displayed once, even if multiple cells call somepkg.foo(). But if cell 5 and cell 592 both call anotherpkg.bad_func() directly, then both will get warnings. (Important exception: if foo() is defined *interactively*, and calls anotherpkg.bad_func(), then every cell that calls foo() will display the warning again. This is unavoidable without fixes to CPython upstream.) Explanation: Python's warning system has some weird quirks. By default, it tries to suppress duplicate warnings, where "duplicate" means the same warning message triggered twice by the same line of code. This requires determining which line of code is responsible for triggering a warning, and this is controlled by the stacklevel= argument to warnings.warn. Basically, though, the idea is that if foo() calls bar() which calls baz() which calls some_deprecated_api(), then baz() will get counted as being "responsible", and the warning system will make a note that the usage of some_deprecated_api() inside baz() has already been warned about and doesn't need to be warned about again. So far so good. To accomplish this, obviously, there has to be a record of somewhere which line this was. You might think that this would be done by recording the filename:linenumber pair in a dict inside the warnings module, or something like that. You would be wrong. What actually happens is that the warnings module will use stack introspection to reach into baz()'s execution environment, create a global (module-level) variable there named __warningregistry__, and then, inside this dictionary, record just the line number. Basically, it assumes that any given module contains only one line 1, only one line 2, etc., so storing the filename is irrelevant. Obviously for interactive code this is totally wrong -- all cells share the same execution environment and global namespace, and they all contain a new line 1. Currently the warnings module treats these as if they were all the same line. In fact they are not the same line; once we have executed a given chunk of code, we will never see those particular lines again. As soon as a given chunk of code finishes executing, its line number labels become meaningless, and the corresponding warning registry entries become meaningless as well. Therefore, with this patch we delete the __warningregistry__ each time we execute a new block of code.

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nbconvertapp.py
320 lines | 11.8 KiB | text/x-python | PythonLexer
#!/usr/bin/env python
"""NbConvert is a utility for conversion of .ipynb files.
Command-line interface for the NbConvert conversion utility.
"""
# Copyright (c) IPython Development Team.
# Distributed under the terms of the Modified BSD License.
from __future__ import print_function
import logging
import sys
import os
import glob
from IPython.core.application import BaseIPythonApplication, base_aliases, base_flags
from IPython.core.profiledir import ProfileDir
from IPython.config import catch_config_error, Configurable
from IPython.utils.traitlets import (
Unicode, List, Instance, DottedObjectName, Type, CaselessStrEnum,
)
from IPython.utils.importstring import import_item
from .exporters.export import get_export_names, exporter_map
from IPython.nbconvert import exporters, preprocessors, writers, postprocessors
from .utils.base import NbConvertBase
from .utils.exceptions import ConversionException
#-----------------------------------------------------------------------------
#Classes and functions
#-----------------------------------------------------------------------------
class DottedOrNone(DottedObjectName):
"""
A string holding a valid dotted object name in Python, such as A.b3._c
Also allows for None type."""
default_value = u''
def validate(self, obj, value):
if value is not None and len(value) > 0:
return super(DottedOrNone, self).validate(obj, value)
else:
return value
nbconvert_aliases = {}
nbconvert_aliases.update(base_aliases)
nbconvert_aliases.update({
'to' : 'NbConvertApp.export_format',
'template' : 'TemplateExporter.template_file',
'writer' : 'NbConvertApp.writer_class',
'post': 'NbConvertApp.postprocessor_class',
'output': 'NbConvertApp.output_base',
'reveal-prefix': 'RevealHelpPreprocessor.url_prefix',
'nbformat': 'NotebookExporter.nbformat_version',
})
nbconvert_flags = {}
nbconvert_flags.update(base_flags)
nbconvert_flags.update({
'stdout' : (
{'NbConvertApp' : {'writer_class' : "StdoutWriter"}},
"Write notebook output to stdout instead of files."
)
})
class NbConvertApp(BaseIPythonApplication):
"""Application used to convert from notebook file type (``*.ipynb``)"""
name = 'ipython-nbconvert'
aliases = nbconvert_aliases
flags = nbconvert_flags
def _log_level_default(self):
return logging.INFO
def _classes_default(self):
classes = [NbConvertBase, ProfileDir]
for pkg in (exporters, preprocessors, writers, postprocessors):
for name in dir(pkg):
cls = getattr(pkg, name)
if isinstance(cls, type) and issubclass(cls, Configurable):
classes.append(cls)
return classes
description = Unicode(
u"""This application is used to convert notebook files (*.ipynb)
to various other formats.
WARNING: THE COMMANDLINE INTERFACE MAY CHANGE IN FUTURE RELEASES.""")
output_base = Unicode('', config=True, help='''overwrite base name use for output files.
can only be used when converting one notebook at a time.
''')
examples = Unicode(u"""
The simplest way to use nbconvert is
> ipython nbconvert mynotebook.ipynb
which will convert mynotebook.ipynb to the default format (probably HTML).
You can specify the export format with `--to`.
Options include {0}
> ipython nbconvert --to latex mynotebook.ipynb
Both HTML and LaTeX support multiple output templates. LaTeX includes
'base', 'article' and 'report'. HTML includes 'basic' and 'full'. You
can specify the flavor of the format used.
> ipython nbconvert --to html --template basic mynotebook.ipynb
You can also pipe the output to stdout, rather than a file
> ipython nbconvert mynotebook.ipynb --stdout
PDF is generated via latex
> ipython nbconvert mynotebook.ipynb --to pdf
You can get (and serve) a Reveal.js-powered slideshow
> ipython nbconvert myslides.ipynb --to slides --post serve
Multiple notebooks can be given at the command line in a couple of
different ways:
> ipython nbconvert notebook*.ipynb
> ipython nbconvert notebook1.ipynb notebook2.ipynb
or you can specify the notebooks list in a config file, containing::
c.NbConvertApp.notebooks = ["my_notebook.ipynb"]
> ipython nbconvert --config mycfg.py
""".format(get_export_names()))
# Writer specific variables
writer = Instance('IPython.nbconvert.writers.base.WriterBase',
help="""Instance of the writer class used to write the
results of the conversion.""")
writer_class = DottedObjectName('FilesWriter', config=True,
help="""Writer class used to write the
results of the conversion""")
writer_aliases = {'fileswriter': 'IPython.nbconvert.writers.files.FilesWriter',
'debugwriter': 'IPython.nbconvert.writers.debug.DebugWriter',
'stdoutwriter': 'IPython.nbconvert.writers.stdout.StdoutWriter'}
writer_factory = Type()
def _writer_class_changed(self, name, old, new):
if new.lower() in self.writer_aliases:
new = self.writer_aliases[new.lower()]
self.writer_factory = import_item(new)
# Post-processor specific variables
postprocessor = Instance('IPython.nbconvert.postprocessors.base.PostProcessorBase',
help="""Instance of the PostProcessor class used to write the
results of the conversion.""")
postprocessor_class = DottedOrNone(config=True,
help="""PostProcessor class used to write the
results of the conversion""")
postprocessor_aliases = {'serve': 'IPython.nbconvert.postprocessors.serve.ServePostProcessor'}
postprocessor_factory = Type()
def _postprocessor_class_changed(self, name, old, new):
if new.lower() in self.postprocessor_aliases:
new = self.postprocessor_aliases[new.lower()]
if new:
self.postprocessor_factory = import_item(new)
# Other configurable variables
export_format = CaselessStrEnum(get_export_names(),
default_value="html",
config=True,
help="""The export format to be used."""
)
notebooks = List([], config=True, help="""List of notebooks to convert.
Wildcards are supported.
Filenames passed positionally will be added to the list.
""")
@catch_config_error
def initialize(self, argv=None):
self.init_syspath()
super(NbConvertApp, self).initialize(argv)
self.init_notebooks()
self.init_writer()
self.init_postprocessor()
def init_syspath(self):
"""
Add the cwd to the sys.path ($PYTHONPATH)
"""
sys.path.insert(0, os.getcwd())
def init_notebooks(self):
"""Construct the list of notebooks.
If notebooks are passed on the command-line,
they override notebooks specified in config files.
Glob each notebook to replace notebook patterns with filenames.
"""
# Specifying notebooks on the command-line overrides (rather than adds)
# the notebook list
if self.extra_args:
patterns = self.extra_args
else:
patterns = self.notebooks
# Use glob to replace all the notebook patterns with filenames.
filenames = []
for pattern in patterns:
# Use glob to find matching filenames. Allow the user to convert
# notebooks without having to type the extension.
globbed_files = glob.glob(pattern)
globbed_files.extend(glob.glob(pattern + '.ipynb'))
if not globbed_files:
self.log.warn("pattern %r matched no files", pattern)
for filename in globbed_files:
if not filename in filenames:
filenames.append(filename)
self.notebooks = filenames
def init_writer(self):
"""
Initialize the writer (which is stateless)
"""
self._writer_class_changed(None, self.writer_class, self.writer_class)
self.writer = self.writer_factory(parent=self)
def init_postprocessor(self):
"""
Initialize the postprocessor (which is stateless)
"""
self._postprocessor_class_changed(None, self.postprocessor_class,
self.postprocessor_class)
if self.postprocessor_factory:
self.postprocessor = self.postprocessor_factory(parent=self)
def start(self):
"""
Ran after initialization completed
"""
super(NbConvertApp, self).start()
self.convert_notebooks()
def convert_notebooks(self):
"""
Convert the notebooks in the self.notebook traitlet
"""
# Export each notebook
conversion_success = 0
if self.output_base != '' and len(self.notebooks) > 1:
self.log.error(
"""UsageError: --output flag or `NbConvertApp.output_base` config option
cannot be used when converting multiple notebooks.
""")
self.exit(1)
exporter = exporter_map[self.export_format](config=self.config)
for notebook_filename in self.notebooks:
self.log.info("Converting notebook %s to %s", notebook_filename, self.export_format)
# Get a unique key for the notebook and set it in the resources object.
basename = os.path.basename(notebook_filename)
notebook_name = basename[:basename.rfind('.')]
if self.output_base:
# strip duplicate extension from output_base, to avoid Basname.ext.ext
if getattr(exporter, 'file_extension', False):
base, ext = os.path.splitext(self.output_base)
if ext == '.' + exporter.file_extension:
self.output_base = base
notebook_name = self.output_base
resources = {}
resources['profile_dir'] = self.profile_dir.location
resources['unique_key'] = notebook_name
resources['output_files_dir'] = '%s_files' % notebook_name
self.log.info("Support files will be in %s", os.path.join(resources['output_files_dir'], ''))
# Try to export
try:
output, resources = exporter.from_filename(notebook_filename, resources=resources)
except ConversionException as e:
self.log.error("Error while converting '%s'", notebook_filename,
exc_info=True)
self.exit(1)
else:
if 'output_suffix' in resources and not self.output_base:
notebook_name += resources['output_suffix']
write_results = self.writer.write(output, resources, notebook_name=notebook_name)
#Post-process if post processor has been defined.
if hasattr(self, 'postprocessor') and self.postprocessor:
self.postprocessor(write_results)
conversion_success += 1
# If nothing was converted successfully, help the user.
if conversion_success == 0:
self.print_help()
sys.exit(-1)
#-----------------------------------------------------------------------------
# Main entry point
#-----------------------------------------------------------------------------
launch_new_instance = NbConvertApp.launch_instance