##// END OF EJS Templates
Moved all converter code into nbconvert subdirectory
Moved all converter code into nbconvert subdirectory

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r10482:87812de9
r10482:87812de9
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base.py
120 lines | 3.7 KiB | text/x-python | PythonLexer
"""
Module that regroups transformer that woudl be applied to ipynb files
before going through the templating machinery.
It exposes convenient classes to inherit from to access configurability
as well as decorator to simplify tasks.
"""
from __future__ import print_function, absolute_import
from IPython.config.configurable import Configurable
from IPython.utils.traitlets import Unicode, Bool, Dict, List
from .config import GlobalConfigurable
class ConfigurableTransformers(GlobalConfigurable):
""" A configurable transformer
Inherit from this class if you wish to have configurability for your
transformer.
Any configurable traitlets this class exposed will be configurable in profiles
using c.SubClassName.atribute=value
you can overwrite cell_transform to apply a transformation independently on each cell
or __call__ if you prefer your own logic. See orresponding docstring for informations.
"""
def __init__(self, config=None, **kw):
super(ConfigurableTransformers, self).__init__(config=config, **kw)
def __call__(self, nb, other):
"""transformation to apply on each notebook.
received a handle to the current notebook as well as a dict of resources
which structure depends on the transformer.
You should return modified nb, other.
If you wish to apply on each cell, you might want to overwrite cell_transform method.
"""
try :
for worksheet in nb.worksheets :
for index, cell in enumerate(worksheet.cells):
worksheet.cells[index], other = self.cell_transform(cell, other, 100*index)
return nb, other
except NotImplementedError:
raise NotImplementedError('should be implemented by subclass')
def cell_transform(self, cell, other, index):
"""
Overwrite if you want to apply a transformation on each cell,
receive the current cell, the resource dict and the index of current cell as parameter.
You should return modified cell and resource dict.
"""
raise NotImplementedError('should be implemented by subclass')
return cell, other
def cell_preprocessor(function):
""" wrap a function to be executed on all cells of a notebook
wrapped function parameters :
cell : the cell
other : external resources
index : index of the cell
"""
def wrappedfunc(nb, other):
for worksheet in nb.worksheets :
for index, cell in enumerate(worksheet.cells):
worksheet.cells[index], other = function(cell, other, index)
return nb, other
return wrappedfunc
@cell_preprocessor
def haspyout_transformer(cell, other, count):
"""
Add a haspyout flag to cell that have it
Easier for templating, where you can't know in advance
wether to write the out prompt
"""
cell.type = cell.cell_type
cell.haspyout = False
for out in cell.get('outputs', []):
if out.output_type == 'pyout':
cell.haspyout = True
break
return cell, other
@cell_preprocessor
def coalesce_streams(cell, other, count):
"""merge consecutive sequences of stream output into single stream
to prevent extra newlines inserted at flush calls
TODO: handle \r deletion
"""
outputs = cell.get('outputs', [])
if not outputs:
return cell, other
new_outputs = []
last = outputs[0]
new_outputs = [last]
for output in outputs[1:]:
if (output.output_type == 'stream' and
last.output_type == 'stream' and
last.stream == output.stream
):
last.text += output.text
else:
new_outputs.append(output)
cell.outputs = new_outputs
return cell, other