hub/venv/lib/python3.7/site-packages/nbconvert/exporters/pdf.py

205 lines
7.8 KiB
Python

"""Export to PDF via latex"""
# Copyright (c) IPython Development Team.
# Distributed under the terms of the Modified BSD License.
import subprocess
import os
import sys
from ipython_genutils.py3compat import which, cast_bytes_py2, getcwd
from traitlets import Integer, List, Bool, Instance, Unicode, default
from testpath.tempdir import TemporaryWorkingDirectory
from .latex import LatexExporter
class LatexFailed(IOError):
"""Exception for failed latex run
Captured latex output is in error.output.
"""
def __init__(self, output):
self.output = output
def __unicode__(self):
return u"PDF creating failed, captured latex output:\n%s" % self.output
def __str__(self):
u = self.__unicode__()
return cast_bytes_py2(u)
def prepend_to_env_search_path(varname, value, envdict):
"""Add value to the environment variable varname in envdict
e.g. prepend_to_env_search_path('BIBINPUTS', '/home/sally/foo', os.environ)
"""
if not value:
return # Nothing to add
envdict[varname] = cast_bytes_py2(value) + os.pathsep + envdict.get(varname, '')
class PDFExporter(LatexExporter):
"""Writer designed to write to PDF files.
This inherits from :class:`LatexExporter`. It creates a LaTeX file in
a temporary directory using the template machinery, and then runs LaTeX
to create a pdf.
"""
export_from_notebook="PDF via LaTeX"
latex_count = Integer(3,
help="How many times latex will be called."
).tag(config=True)
latex_command = List([u"xelatex", u"{filename}", "-quiet"],
help="Shell command used to compile latex."
).tag(config=True)
bib_command = List([u"bibtex", u"{filename}"],
help="Shell command used to run bibtex."
).tag(config=True)
verbose = Bool(False,
help="Whether to display the output of latex commands."
).tag(config=True)
texinputs = Unicode(help="texinputs dir. A notebook's directory is added")
writer = Instance("nbconvert.writers.FilesWriter", args=(), kw={'build_directory': '.'})
output_mimetype = "application/pdf"
_captured_output = List()
@default('file_extension')
def _file_extension_default(self):
return '.pdf'
def run_command(self, command_list, filename, count, log_function, raise_on_failure=None):
"""Run command_list count times.
Parameters
----------
command_list : list
A list of args to provide to Popen. Each element of this
list will be interpolated with the filename to convert.
filename : unicode
The name of the file to convert.
count : int
How many times to run the command.
raise_on_failure: Exception class (default None)
If provided, will raise the given exception for if an instead of
returning False on command failure.
Returns
-------
success : bool
A boolean indicating if the command was successful (True)
or failed (False).
"""
command = [c.format(filename=filename) for c in command_list]
# On windows with python 2.x there is a bug in subprocess.Popen and
# unicode commands are not supported
if sys.platform == 'win32' and sys.version_info < (3,0):
#We must use cp1252 encoding for calling subprocess.Popen
#Note that sys.stdin.encoding and encoding.DEFAULT_ENCODING
# could be different (cp437 in case of dos console)
command = [c.encode('cp1252') for c in command]
# This will throw a clearer error if the command is not found
cmd = which(command_list[0])
if cmd is None:
link = "https://nbconvert.readthedocs.io/en/latest/install.html#installing-tex"
raise OSError("{formatter} not found on PATH, if you have not installed "
"{formatter} you may need to do so. Find further instructions "
"at {link}.".format(formatter=command_list[0], link=link))
times = 'time' if count == 1 else 'times'
self.log.info("Running %s %i %s: %s", command_list[0], count, times, command)
shell = (sys.platform == 'win32')
if shell:
command = subprocess.list2cmdline(command)
env = os.environ.copy()
prepend_to_env_search_path('TEXINPUTS', self.texinputs, env)
prepend_to_env_search_path('BIBINPUTS', self.texinputs, env)
prepend_to_env_search_path('BSTINPUTS', self.texinputs, env)
with open(os.devnull, 'rb') as null:
stdout = subprocess.PIPE if not self.verbose else None
for index in range(count):
p = subprocess.Popen(command, stdout=stdout, stderr=subprocess.STDOUT,
stdin=null, shell=shell, env=env)
out, _ = p.communicate()
if p.returncode:
if self.verbose:
# verbose means I didn't capture stdout with PIPE,
# so it's already been displayed and `out` is None.
out = u''
else:
out = out.decode('utf-8', 'replace')
log_function(command, out)
self._captured_output.append(out)
if raise_on_failure:
raise raise_on_failure(
'Failed to run "{command}" command:\n{output}'.format(
command=command, output=out))
return False # failure
return True # success
def run_latex(self, filename, raise_on_failure=LatexFailed):
"""Run xelatex self.latex_count times."""
def log_error(command, out):
self.log.critical(u"%s failed: %s\n%s", command[0], command, out)
return self.run_command(self.latex_command, filename,
self.latex_count, log_error, raise_on_failure)
def run_bib(self, filename, raise_on_failure=False):
"""Run bibtex one time."""
filename = os.path.splitext(filename)[0]
def log_error(command, out):
self.log.warning('%s had problems, most likely because there were no citations',
command[0])
self.log.debug(u"%s output: %s\n%s", command[0], command, out)
return self.run_command(self.bib_command, filename, 1, log_error, raise_on_failure)
def from_notebook_node(self, nb, resources=None, **kw):
latex, resources = super(PDFExporter, self).from_notebook_node(
nb, resources=resources, **kw
)
# set texinputs directory, so that local files will be found
if resources and resources.get('metadata', {}).get('path'):
self.texinputs = resources['metadata']['path']
else:
self.texinputs = getcwd()
self._captured_outputs = []
with TemporaryWorkingDirectory():
notebook_name = 'notebook'
resources['output_extension'] = '.tex'
tex_file = self.writer.write(latex, resources, notebook_name=notebook_name)
self.log.info("Building PDF")
self.run_latex(tex_file)
if self.run_bib(tex_file):
self.run_latex(tex_file)
pdf_file = notebook_name + '.pdf'
if not os.path.isfile(pdf_file):
raise LatexFailed('\n'.join(self._captured_output))
self.log.info('PDF successfully created')
with open(pdf_file, 'rb') as f:
pdf_data = f.read()
# convert output extension to pdf
# the writer above required it to be tex
resources['output_extension'] = '.pdf'
# clear figure outputs, extracted by latex export,
# so we don't claim to be a multi-file export.
resources.pop('outputs', None)
return pdf_data, resources