Source code for pyexcel.internal.generators


    Defintion for the sheet and book generators.

    :copyright: (c) 2015-2020 by Onni Software Ltd.
    :license: New BSD License
from pyexcel._compact import OrderedDict
from pyexcel.internal.common import SheetIterator

[docs]class SheetStream(object): """ Memory efficient sheet representation This class wraps around the data read from pyexcel-io. Comparing with :class:`pyexcel.Sheet`, the instance of this class does not load all data into memory. Hence it performs better when dealing with big data. If you would like to do custom rendering for each row of the two dimensional data, you would need to pass a row formatting/rendering function to the parameter "renderer" of pyexcel's signature functions. """
[docs] def __init__(self, name, payload): = name self.payload = payload self.colnames = []
def to_array(self): """ Simply return the generator """ return self.payload @property def array(self): """array attribute""" return list(self.payload) def get_internal_array(self): return self.payload
[docs]class BookStream(object): """ Memory efficient book representation Comparing with :class:`pyexcel.Book`, the instace of this class uses :class:`pyexcel.generators.SheetStream` as its internal repesentation of sheet objects. Because `SheetStream` does not read data into memory, it is memory efficient. """
[docs] def __init__(self, sheets=None, filename="memory", path=None): """Book constructor Selecting a specific book according to filename extension :param OrderedDict/dict sheets: a dictionary of data :param str filename: the physical file :param str path: the relative path or absolute path :param set keywords: additional parameters to be passed on """ self.path = path self.filename = filename self.name_array = [] if sheets: self.load_from_sheets(sheets) else: self.sheets = {}
def load_from_sheets(self, sheets): """Load content from existing sheets :param dict sheets: a dictionary of sheets. Each sheet is a list of lists """ if sheets is None: return self.sheets = OrderedDict() keys = sheets.keys() if not isinstance(sheets, OrderedDict): # if the end user does not care about the order # we put alphatical order keys = sorted(keys) for name in keys: sheet = SheetStream(name, sheets[name]) # this sheets keep sheet order self.sheets.update({name: sheet}) # this provide the convenience of access the sheet self.__dict__[name] = sheet self.name_array = list(self.sheets.keys()) def sheet_names(self): return self.name_array def to_dict(self): """ Get book data structure as a dictionary """ the_dict = OrderedDict() for sheet in self: the_dict.update({ sheet.payload}) return the_dict def __iter__(self): return SheetIterator(self) def number_of_sheets(self): """Return the number of sheets""" return len(self.name_array) def __getitem__(self, index): if isinstance(index, int): if index < len(self.name_array): sheet_name = self.name_array[index] return self.sheets[sheet_name] else: sheet_name = index return self.sheets[sheet_name]