2-hypermedia_pagination.py

#!/usr/bin/env python3

"""
Module 2-hypermedia_pagination
"""
import csv
import math
from typing import List


def index_range(page: int, page_size: int) -> tuple:
    """
    Takes two integer arguments page and page_size.
    Returns a tuple of size two containing a start
    index and an end index corresponding to the range
    of indexes to return in a list for those particular
    pagination parameters.
    """
    index_tuple = page_size * (page - 1), page * page_size
    return index_tuple


class Server:
    """Server class to paginate a database of popular baby names.
    """
    DATA_FILE = "Popular_Baby_Names.csv"

    def __init__(self):
        """init object"""
        self.__dataset = None

    def dataset(self) -> List[List]:
        """Cached dataset
        """
        if self.__dataset is None:
            with open(self.DATA_FILE) as f:
                reader = csv.reader(f)
                dataset = [row for row in reader]
            self.__dataset = dataset[1:]
        return self.__dataset

    def get_page(self, page: int = 1, page_size: int = 10) -> List[List]:
        """
        paginate dataset
        """
        assert type(page) is int and page > 0
        assert type(page_size) is int and page_size > 0

        indexes = index_range(page, page_size)
        try:
            data = self.dataset()
            return data[indexes[0]: indexes[1]]
        except IndexError:
            return []

    def get_hyper(self, page: int = 1, page_size: int = 10) -> dict:
        """
        Illustration of hypermedia pagination
        """
        data = self.get_page(page, page_size)
        total_pages = math.ceil(len(self.dataset()) / page_size)
        next_page = page + 1 if page < total_pages else None
        prev_page = page - 1 if page > 1 else None

        return {
                "page_size": len(data),
                "page": page,
                "data": data,
                "next_page": next_page,
                "prev_page": prev_page,
                "total_pages": total_pages
                }