add possibility to preprocess ipynb files

converters/template.py

@@ -1,151 +1,165 b''
 """Base classes for the notebook conversion pipeline.
 
 This module defines Converter, from which all objects designed to implement
 a conversion of IPython notebooks to some other format should inherit.
 """
 #-----------------------------------------------------------------------------
 # Copyright (c) 2012, the IPython Development Team.
 #
 # Distributed under the terms of the Modified BSD License.
 #
 # The full license is in the file COPYING.txt, distributed with this software.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
 from __future__ import print_function, absolute_import
 
 # Stdlib imports
 import io
 import os
 from IPython.utils import path
 
 from jinja2 import Environment, FileSystemLoader
 env = Environment(
-        loader=FileSystemLoader('./templates/'), 
+        loader=FileSystemLoader('./templates/'),
         extensions=['jinja2.ext.loopcontrols']
         )
 
 # IPython imports
 from IPython.nbformat import current as nbformat
 from IPython.config.configurable import Configurable
 from IPython.utils.traitlets import ( Unicode, Any)
 
 # Our own imports
 from IPython.utils.text import indent
 from .utils import remove_ansi
 from markdown import markdown
 from .utils import highlight, ansi2html
 #-----------------------------------------------------------------------------
 # Class declarations
 #-----------------------------------------------------------------------------
 def rm_fake(strng):
     return strng.replace('/files/', '')
 
 class ConversionException(Exception):
     pass
 
 
 def python_comment(string):
     return '# '+'\n# '.join(string.split('\n'))
 
 
 
 def header_body():
     """Return the body of the header as a list of strings."""
 
     from pygments.formatters import HtmlFormatter
 
     header = []
     static = os.path.join(path.get_ipython_package_dir(),
     'frontend', 'html', 'notebook', 'static',
     )
     here = os.path.split(os.path.realpath(__file__))[0]
     css = os.path.join(static, 'css')
     for sheet in [
         # do we need jquery and prettify?
         # os.path.join(static, 'jquery', 'css', 'themes', 'base',
         # 'jquery-ui.min.css'),
         # os.path.join(static, 'prettify', 'prettify.css'),
         os.path.join(css, 'boilerplate.css'),
         os.path.join(css, 'fbm.css'),
         os.path.join(css, 'notebook.css'),
         os.path.join(css, 'renderedhtml.css'),
         # our overrides:
         os.path.join(here, '..', 'css', 'static_html.css'),
     ]:
 
         with io.open(sheet, encoding='utf-8') as f:
             s = f.read()
             header.append(s)
 
     pygments_css = HtmlFormatter().get_style_defs('.highlight')
     header.append(pygments_css)
     return header
 
 inlining = {}
 inlining['css'] = header_body()
 
 
 def filter_data_type(output):
     for fmt in ['html', 'pdf', 'svg', 'latex', 'png', 'jpg', 'jpeg' , 'text']:
         if fmt in output:
             return [fmt]
 
 
 env.filters['filter_data_type'] = filter_data_type
 env.filters['pycomment'] = python_comment
 env.filters['indent'] = indent
 env.filters['rm_fake'] = rm_fake
 env.filters['rm_ansi'] = remove_ansi
 env.filters['markdown'] = markdown
 env.filters['highlight'] = highlight
 env.filters['ansi2html'] = ansi2html
 
 class ConverterTemplate(Configurable):
 
     display_data_priority = ['pdf', 'svg', 'png', 'jpg', 'text']
     #-------------------------------------------------------------------------
     # Instance-level attributes that are set in the constructor for this
     # class.
     #-------------------------------------------------------------------------
     infile = Any()
 
 
     infile_dir = Unicode()
 
-    def __init__(self, tplfile='fullhtml', config=None, **kw):
+    def __init__(self, tplfile='fullhtml', preprocessors=[], config=None, **kw):
+        """
+        preprocessors: list of function to run on ipynb json data before conversion
+        to extract/inline file,
+
+
+
+        """
         self.template = env.get_template(tplfile+'.tpl')
         self.nb = None
+        self.preprocessors = preprocessors
         super(ConverterTemplate, self).__init__(config=config, **kw)
 
     def process(self):
-        converted_cells = []
-        for worksheet in self.nb.worksheets:
+        nb = self.nb
+
+        for preprocessor in self.preprocessors:
+            nb = preprocessor(nb,{})
+
+        worksheets = []
+        for worksheet in nb.worksheets:
             for cell in worksheet.cells:
                 cell.type = cell.cell_type
                 cell.haspyout = False
                 for out in cell.get('outputs', []):
                     if out.output_type == 'pyout':
                         cell.haspyout = True
                         break
-            converted_cells.append(worksheet)
+            worksheets.append(worksheet)
+
 
-        return converted_cells
+        return worksheets
 
     def convert(self):
         """ convert the ipynb file
 
         return both the converted ipynb file and a dict containing potential
         other resources
         """
         return self.template.render(worksheets=self.process(), inlining=inlining), {}
 
 
     def read(self, filename):
         "read and parse notebook into NotebookNode called self.nb"
         with io.open(filename) as f:
             self.nb = nbformat.read(f, 'json')