class_sync/scraper.py

from bs4 import BeautifulSoup as BS
import datetime
import re
from operator import sub
def dateparse(datetime_str):
    date = '%b %d, %Y'
    time = '%I:%M %p'
    try:
        return datetime.datetime.strptime(datetime_str,date)
    except ValueError:
        return datetime.datetime.strptime(datetime_str,time)
days = [None,'M','T','W','R','F',None]
simp_exceptions = ['Grade Mode']
def datetime2date_time(dtime,mode):
    if mode == 'date':
        return datetime.date(dtime.year,dtime.month,dtime.day)
    elif mode == 'time':
        return datetime.time(dtime.hour,dtime.minute,dtime.second)
def seconds_from_midnight(t):
    return t.hour*60**2+ t.minute*60+t.second
class Class:
    def __init__(self,title,abrv,session,days,location,time_range,date_range,lab=None):
        self.title = title
        self.abrv = abrv
        self.session = session
        self.days = days
        self.location = location
        self.time_range = time_range
        self.lab = lab
        self.date_range = date_range
    # data is a list of two html tables
    def scrape(self,data):
        info,times = data
        # info
        title,abrv,sesession = info.find('caption').text.split(' - ')
        session = int(self.session)
        rows = info.find_all('tr')
        for row in rows:
            name = row.find('th').text.rstrip(':')
            data = re.sub(r'^ +|[\n\r\t]','',row.find('td').text)

            if name == 'Status':
                type,date = data.split(' on ')
                type = type.replace('*','')
                self.type = type
                self.registration_date = dateparse(date)
            else:
                if name in simp_exceptions:
                    name = name.lower().replace(' ','_')
                else:
                    name = name.lower().split(' ')[-1]
                if name != 'instructor':
                    data = data.lower()
                try:
                    data = int(re.sub(r'\.\d+','',data))
                except:

                    pass
                self.__dict__[name] = data

        # time
        headers,*data = times.find_all('tr')
        headers = (header.text.lower() for header in headers.find_all('th'))
        if len(data) > 1:
            data,lab = map(lambda row: parse_horz_row(headers,row),data[:2])
            lab = Class(title + " - Lab",abrv,session,**lab)

        else:
            lab = None
            data = data[0]

        return Class(title,abrv,session,lab=lab,**data)

    def parse_horz_row(headers,row):
        data = (col.text for col in row.find_all('td'))
        ret = {}
        time_data = dict(zip(headers,data))
        if time_data['time'] == 'TBA':
            ret['time_range'] = None
        else:
            s,e = map(dateparse,time_data['time'].split(' - '))
            ret['time_range'] = (
                datetime2date_time(s,'time'),
                datetime2date_time(e,'time'),
                )
        s,e = map(dateparse,time_data['date range'].split(' - '))
        ret['date_range'] = (
            datetime2date_time(s,'date'),
            datetime2date_time(e,'date'),
            )
        time_data['days'] = re.sub('[^{}]'.format(''.join(filter(bool,days))),'',time_data['days'])
        ret['days'] = list(days.index(time_data['days'][i]) for i in range(len(time_data['days'])))
        ret['location'] = time_data['where']
        return ret

    @property
    def length(self):
        return datetime.timedelta(seconds = sub(
            seconds_from_midnight(self.time_range[1]),
            seconds_from_midnight(self.time_range[0]),
            ))


def get_classes(page):
    if not isinstance(page,BS):
        page = BS(page,'lxml')
    tables = page.find_all('table',attrs= {'class':'datadisplaytable'})
    groups = ((tables[i],tables[i+1]) for i in range(0,len(tables),2))
    return list(map(Class.scrape,groups))

if __name__ == "__main__":
    with open('schedule.html') as file:
        page = BS(file.read())
    class1,*classes = get_classes(page)