librarian/embeds/latex.py

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