Random date gen class. Returns a tuple of a start date and end date

Question

Just interested in any comments about the way the code is written. I am very new to python and programming. I did think about a func with a generator, but thought this approach was better.

from datetime import date
from datetime import timedelta

import calendar
import random

class rand_dates(object):
    '''
        returns a date range as tuple of a random start date in the current year and an end date + random.randint(term) param. 
    the end date can exceed the current year.
        my usage: i want a random reservation date for a hotel stay. 
    A base year can also be passed as a param if another year is required other than the current year
    '''

    def __init__(self, term = 5, year=None):
        self.term = term
        self.year = year

    def __iter__(self):
        return self

    def next(self):
        td = date.today()
        if self.year == None:
            y = td.year
        else:
            y = self.year

        m = random.randint(1,12)
        d_in_month = calendar.monthrange(y,m)[1]
        d = random.randint(1,d_in_month)
        sd = date(y,m,d)
        ed= sd + timedelta(days=random.randint(1,self.term))
        return (sd,ed)

Answer 1

You thought about using a generator… and why did you reject the idea? If you have an object that does nothing other than iterating, then you might as well make it a generator — that's exactly what they are for.

The code is generally sound. In my opinion, it could flow better if you defined the variables in a more logical order: (random year, random month, random day), followed by (random span), then packaging the results.

The meaning of the term parameter is unclear. I would prefer a more explicit name. The default value, 5, is unexpected to me. Choose either:

• A "sensible" default of 1 day, because that is a natural lower limit for a hotel stay (unless you run one of those sleazy hotels that rents rooms by the hour)
• A default value of 0 days, because 0 is the additive identity
• No default at all: make it a required parameter

In any case, it's probably a good idea to handle max_days=0 correctly without crashing.

The docstring is a bit cumbersome, and slightly self-contradictory when it comes to explaining the year parameter.

import calendar
from datetime import date, timedelta
import random

def rand_dates(max_days=1, year=None):
    '''
    Returns a date range as (start_date, end_date) tuple.

    The start date is a random date in the specified year (defaulting
    to the current year).

    The end date is a random date between 1 and max_days (inclusive) after
    the start date.

    Example usage: Picking random check-in and check-out dates for a hotel stay. 
    '''
    while True:
        y = year or date.today().year
        m = random.randint(1, 12)
        d = random.randint(1, calendar.monthrange(y, m)[1])
        days = random.randint(1, max_days) if max_days > 0 else 0
        start_date = date(y, m, d)
        yield start_date, start_date + timedelta(days=days)