Source code for pyexcel.core

"""
    pyexcel.core
    ~~~~~~~~~~~~~~~~~~~

    A list of pyexcel signature functions

    :copyright: (c) 2015-2016 by Onni Software Ltd.
    :license: New BSD License
"""
import re

from .sheets import VALID_SHEET_PARAMETERS, Sheet, SheetStream
from .book import Book, BookStream
from .constants import (
    MESSAGE_DEPRECATED_OUT_FILE,
    MESSAGE_DEPRECATED_CONTENT,
    MESSAGE_ERROR_02,
    MESSAGE_ERROR_NO_HANDLER
)
from .sources import sources
from . import params
from .factory import SourceFactory
from ._compact import PY2
from pyexcel_io.manager import RWManager


SourceFactory.register_sources(sources)


[docs]def get_sheet(**keywords): """Get an instance of :class:`Sheet` from an excel source :param file_name: a file with supported file extension :param file_content: the file content :param file_stream: the file stream :param file_type: the file type in *content* :param session: database session :param table: database table :param model: a django model :param adict: a dictionary of one dimensional arrays :param url: a download http url for your excel file :param with_keys: load with previous dictionary's keys, default is True :param records: a list of dictionaries that have the same keys :param array: a two dimensional array, a list of lists :param keywords: additional parameters, see :meth:`Sheet.__init__` :param sheet_name: sheet name. if sheet_name is not given, the default sheet at index 0 is loaded Not all parameters are needed. Here is a table ========================== ========================================= source parameters ========================== ========================================= loading from file file_name, sheet_name, keywords loading from memory file_type, content, sheet_name, keywords loading from sql session, table loading from sql in django model loading from query sets any query sets(sqlalchemy or django) loading from dictionary adict, with_keys loading from records records loading from array array ========================== ========================================= see also :ref:`a-list-of-data-structures` """ sheet_params = {} for field in VALID_SHEET_PARAMETERS: if field in keywords: sheet_params[field] = keywords.pop(field) named_content = _get_content(**keywords) sheet = Sheet(named_content.payload, named_content.name, **sheet_params) return sheet
def _get_content(**keywords): if params.DEPRECATED_CONTENT in keywords: print(MESSAGE_DEPRECATED_CONTENT) keywords[params.FILE_CONTENT] = keywords.pop( params.DEPRECATED_CONTENT) source = SourceFactory.get_source(**keywords) if source is not None: sheets = source.get_data() sheet_name, data = one_sheet_tuple(sheets.items()) return SheetStream(sheet_name, data) raise NotImplementedError(MESSAGE_ERROR_NO_HANDLER)
[docs]def get_book(**keywords): """Get an instance of :class:`Book` from an excel source :param file_name: a file with supported file extension :param file_content: the file content :param file_stream: the file stream :param file_type: the file type in *content* :param session: database session :param tables: a list of database table :param models: a list of django models :param bookdict: a dictionary of two dimensional arrays :param url: a download http url for your excel file see also :ref:`a-list-of-data-structures` Here is a table of parameters: ========================== =============================== source parameters ========================== =============================== loading from file file_name, keywords loading from memory file_type, content, keywords loading from sql session, tables loading from django models models loading from dictionary bookdict ========================== =============================== Where the dictionary should have text as keys and two dimensional array as values. """ book_stream = _get_book(**keywords) book = Book(book_stream.to_dict(), filename=book_stream.filename, path=book_stream.path) return book
def _get_book(**keywords): """Get an instance of :class:`Book` from an excel source Where the dictionary should have text as keys and two dimensional array as values. """ if params.DEPRECATED_CONTENT in keywords: print(MESSAGE_DEPRECATED_CONTENT) keywords[params.FILE_CONTENT] = keywords.pop( params.DEPRECATED_CONTENT) source = SourceFactory.get_book_source(**keywords) if source is not None: sheets = source.get_data() filename, path = source.get_source_info() book = BookStream(sheets, filename=filename, path=path) return book raise NotImplementedError(MESSAGE_ERROR_NO_HANDLER) def split_keywords(**keywords): dest_keywords = {} source_keywords = {} for key in keywords.keys(): result = re.match(params.STARTS_WITH_DEST, key) if result: dest_keywords[result.group(1)] = keywords[key] else: source_keywords[key] = keywords[key] if params.DEPRECATED_OUT_FILE in keywords: print(MESSAGE_DEPRECATED_OUT_FILE) dest_keywords[params.FILE_NAME] = keywords.pop( params.DEPRECATED_OUT_FILE) if params.DEPRECATED_CONTENT in keywords: print(MESSAGE_DEPRECATED_CONTENT) dest_keywords[params.FILE_CONTENT] = keywords.pop( params.DEPRECATED_CONTENT) return dest_keywords, source_keywords
[docs]def save_as(**keywords): """Save a sheet from a data srouce to another one It accepts two sets of keywords. Why two sets? one set is source, the other set is destination. In order to distiguish the two sets, source set will be exactly the same as the ones for :meth:`pyexcel.get_sheet`; destination set are exactly the same as the ones for :class:`pyexcel.Sheet.save_as` but require a 'dest' prefix. :param keywords: additional keywords can be found at :meth:`pyexcel.get_sheet` :param dest_file_name: another file name. **out_file** is deprecated though is still accepted. :param dest_file_type: this is needed if you want to save to memory :param dest_session: the target database session :param dest_table: the target destination table :param dest_model: the target django model :param dest_mapdict: a mapping dictionary, see :meth:`pyexcel.Sheet.save_to_memory` :param dest_initializer: a custom initializer function for table or model :param dest_mapdict: nominate headers :param dest_batch_size: object creation batch size. it is Django specific if csv file is destination format, python csv `fmtparams <https://docs.python.org/release/3.1.5/ library/csv.html#dialects-and-formatting-parameters>`_ are accepted for example: dest_lineterminator will replace default '\r\n' to the one you specified :returns: IO stream if saving to memory. None otherwise ================= ============================================= Saving to source parameters ================= ============================================= file dest_file_name, dest_sheet_name, keywords with prefix 'dest' memory dest_file_type, dest_content, dest_sheet_name, keywords with prefix 'dest' sql dest_session, table, dest_initializer, dest_mapdict django model dest_model, dest_initializer, dest_mapdict, dest_batch_size ================= ============================================= """ dest_keywords, source_keywords = split_keywords(**keywords) dest_source = SourceFactory.get_writeable_source(**dest_keywords) if dest_source is not None: sheet_params = {} for field in VALID_SHEET_PARAMETERS: if field in source_keywords: sheet_params[field] = source_keywords.pop(field) sheet = _get_content(**source_keywords) if sheet_params != {}: sheet = Sheet(sheet.payload, sheet.name, **sheet_params) sheet.save_to(dest_source) if params.FILE_TYPE in dest_source.fields: _try_put_file_read_pointer_to_its_begining(dest_source.content) return dest_source.content else: raise ValueError(MESSAGE_ERROR_02)
[docs]def save_book_as(**keywords): """Save a book from a data source to another one :param dest_file_name: another file name. **out_file** is deprecated though is still accepted. :param dest_file_type: this is needed if you want to save to memory :param dest_session: the target database session :param dest_tables: the list of target destination tables :param dest_models: the list of target destination django models :param dest_mapdicts: a list of mapping dictionaries :param dest_initializers: table initialization fuctions :param dest_mapdicts: to nominate a model or table fields. Optional :param dest_batch_size: batch creation size. Optional :param keywords: additional keywords can be found at :meth:`pyexcel.get_sheet` :returns: IO stream if saving to memory. None otherwise ================ ============================================ Saving to source parameters ================ ============================================ file dest_file_name, dest_sheet_name, keywords with prefix 'dest' memory dest_file_type, dest_content, dest_sheet_name, keywords with prefix 'dest' sql dest_session, dest_tables, dest_table_init_func, dest_mapdict django model dest_models, dest_initializers, dest_mapdict, dest_batch_size ================ ============================================ """ dest_keywords, source_keywords = split_keywords(**keywords) dest_source = SourceFactory.get_writeable_book_source(**dest_keywords) if dest_source is not None: book = _get_book(**source_keywords) book.save_to(dest_source) if params.FILE_TYPE in dest_source.fields: _try_put_file_read_pointer_to_its_begining(dest_source.content) return dest_source.content else: raise ValueError(MESSAGE_ERROR_02)
[docs]def get_array(**keywords): """Obtain an array from an excel source :param keywords: see :meth:`~pyexcel.get_sheet` """ sheet = get_sheet(**keywords) if sheet: return sheet.to_array() else: return None
[docs]def get_dict(name_columns_by_row=0, **keywords): """Obtain a dictionary from an excel source :param name_columns_by_row: specify a row to be a dictionary key. It is default to 0 or first row. :param keywords: see :meth:`~pyexcel.get_sheet` If you would use a column index 0 instead, you should do:: get_dict(name_columns_by_row=-1, name_rows_by_column=0) """ sheet = get_sheet(name_columns_by_row=name_columns_by_row, **keywords) if sheet: return sheet.to_dict() else: return None
[docs]def get_records(name_columns_by_row=0, **keywords): """Obtain a list of records from an excel source :param name_columns_by_row: specify a row to be a dictionary key. It is default to 0 or first row. :param keywords: see :meth:`~pyexcel.get_sheet` If you would use a column index 0 instead, you should do:: get_records(name_columns_by_row=-1, name_rows_by_column=0) """ sheet = get_sheet(name_columns_by_row=name_columns_by_row, **keywords) if sheet: return sheet.to_records() else: return None
[docs]def get_book_dict(**keywords): """Obtain a dictionary of two dimensional arrays :param keywords: see :meth:`~pyexcel.get_book` """ book = get_book(**keywords) if book: return book.to_dict() else: return None
def get_io_type(file_type): """ Return the io stream types, string or bytes """ io_type = RWManager.get_io_type(file_type) if io_type is None: io_type = "string" return io_type def one_sheet_tuple(items): if not PY2: items = list(items) return items[0][0], items[0][1] def _try_put_file_read_pointer_to_its_begining(a_stream): if PY2: try: a_stream.seek(0) except IOError: pass else: import io try: a_stream.seek(0) except io.UnsupportedOperation: pass