pelican-plugins/rmd_reader/rmd_reader.py

#-*- conding: utf-8 -*-

import os
import warnings

from pelican import readers
from pelican import signals
from pelican import settings
from pelican.utils import pelican_open
from markdown import Markdown

#import pelicanconf

knitr = None
rmd = False

def initsignal(pelicanobj):
    global knitr,rmd
    try:
        with warnings.catch_warnings():
            warnings.simplefilter("ignore")
            from rpy2.robjects.packages import importr
        knitr = importr('knitr')
        idx = knitr.opts_knit.names.index('set')
        PATH = pelicanobj.settings.get('PATH','%s/content' % settings.DEFAULT_CONFIG.get('PATH'))
        knitr.opts_knit[idx](**{'base.dir': PATH})
        idy = knitr.opts_chunk.names.index('set')
        knitroptschunk = pelicanobj.settings.get('KNITR_OPTS_CHUNK',None)
        if knitroptschunk is not None:     
            knitr.opts_chunk[idy](**{str(k): v for k,v in knitroptschunk.iteritems()})
        rmd = True
    except ImportError:
        rmd = False
    
class RmdReader(readers.BaseReader):
    enabled = rmd
    file_extensions = ['Rmd', 'rmd']

    # You need to have a read method, which takes a filename and returns
    # some content and the associated metadata.
    def read(self, filename):
        """Parse content and metadata of markdown files"""
        # replace single backslashes with double backslashes
        filename = filename.replace('\\', '\\\\')
        # parse Rmd file - generate md file
        md_filename = filename.replace('.Rmd', '.aux').replace('.rmd', '.aux')
        knitr.knit(filename, md_filename, quiet=True, encoding='UTF-8')
        # read md file - create a MarkdownReader
        md_reader = readers.MarkdownReader(self.settings)
        content, metadata = md_reader.read(md_filename)
        # remove md file
        os.remove(md_filename)
        return content, metadata

def add_reader(readers):
    readers.reader_classes['rmd'] = RmdReader

def register():
    signals.readers_init.connect(add_reader)
    signals.initialized.connect(initsignal)