librarian/embeds/latex.py

   1 import os
   2 import shutil
   3 from subprocess import call, PIPE
   4 from tempfile import mkdtemp
   5 from librarian import get_resource
   6 from . import DataEmbed, create_embed, downgrades_to, converts_to
   7
   8 class LaTeX(DataEmbed):
   9     @downgrades_to('image/png')
  10     def to_png(self):
  11         tmpl = open(get_resource('res/embeds/latex/template.tex')).read().decode('utf-8')
  12         tempdir = mkdtemp('-librarian-embed-latex')
  13         fpath = os.path.join(tempdir, 'doc.tex')
  14         with open(fpath, 'w') as f:
  15             f.write((tmpl % {'code': self.data}).encode('utf-8'))
  16         call(['xelatex', '-interaction=batchmode', '-output-directory', tempdir, fpath], stdout=PIPE, stderr=PIPE)
  17         call(['convert', '-density', '150', os.path.join(tempdir, 'doc.pdf'), '-trim',
  18                 os.path.join(tempdir, 'doc.png')])
  19         pngdata = open(os.path.join(tempdir, 'doc.png')).read()
  20         shutil.rmtree(tempdir)
  21         return create_embed('image/png', data=pngdata)