epub_date.py

"""Module to handle dates from the Journal Publishing tag set
<date> Element: http://dtd.nlm.nih.gov/publishing/tag-library/2.0/n-kh50.html
<pub-date>: http://dtd.nlm.nih.gov/publishing/tag-library/2.0/n-d8x0.html
Citation elements also require date information
"""

import datetime

class DateInfo(object):
    """Date with extra info
    datenode -- the XML Element containing the date info
    """
    def __init__(self, datenode):
        self.type = ''
        self.season = ''
        self.date = None
        self.year = 0
        self.month = 0
        self.day = 0
        
        self.monthlist = ['January', 'February', 'March', 'April', 'May', 
                          'June', 'July', 'August', 'September', 'October', 
                          'November', 'December']
        
        self.parse(datenode)
        try:
            self.date = datetime.date(self.year, self.month, self.day)
        except ValueError:
            if self.day == 0:
                pass
            else:
                raise ValueError('day is out of range for month')
        
    def parse(self, datenode):
        """Handle the node contents
        datenode -- the XML Element containing the date info
        returns a 3-tuple: (year, month, day)
        """
        
        if datenode.tagName == 'date':
            self.type = datenode.getAttribute('date-type')
        elif datenode.tagName == 'pub-date':
            self.type = datenode.getAttribute('pub-type')
        
        try:
            self.season = datenode.getElementsByTagName('season')[0].firstChild.data
        except IndexError:
            try:
                self.day = int(datenode.getElementsByTagName('day')[0].firstChild.data)
            except IndexError:
                pass
            try:
                self.month = int(datenode.getElementsByTagName('month')[0].firstChild.data)
            except IndexError:
                pass
            except ValueError:
                data = datenode.getElementsByTagName('month')[0].firstChild.data
                self.month = self.monthlist.index(data) + 1
        
        self.year = int(datenode.getElementsByTagName('year')[0].firstChild.data)
    
    def niceString(self):
        retstr = '{0} {1}, {2}'.format(self.monthlist[self.month - 1], self.day,
                                       self.year)
        return retstr
    
    def dateString(self):
        newstring = '{0}'.format(self.year)
        if self.month:
            monstr = str(self.month).zfill(2)
            newstring += '-{0}'.format(monstr)
        if self.day:
            daystr = str(self.day).zfill(2)
            newstring += '-{0}'.format(daystr)
        return newstring