pyfastexcel 0.0.6

High performace excel file generation library.

pyfastexcel

This package enables high-performance Excel writing by integrating with the streaming API from the golang package excelize. Users can leverage this functionality without the need to write any Go code, as the entire process can be accomplished through Python.

Installation

Install via pip (Recommended)

You can easily install the package via pip

pip install pyfastexcel

Install manually

If you prefer to build the package manually, follow these steps:

1. Clone the repository:

   git clone https://github.com/Zncl2222/pyfastexcel.git
   

2. Go to the project root directory:

   cd pyfastexcel
   

3. Install the required golang packages:

   go mod download
   

4. Build the Golang shared library using the Makefile:

   make
   

5. Install the required python packages:

   pip install -r requirements.txt
   

   or

   pipenv install
   

6. Import the project and start using it!

Features

• Python and Golang Integration: Seamlessly call Golang built shared libraries from Python.

• No Golang Code Required: Users can solely rely on Python for Excel file generation, eliminating the need for Golang expertise.

How it Works

The core functionality revolves around encoding Excel cell data and styles, or any other Excel properties, into a JSON string within Python. This JSON payload is then passed through ctypes to a Golang shared library. In Golang, the JSON is parsed, and using the streaming writer of excelize to wrtie excel in high performance.

Usage

The index assignment is now avaliable in Workbook and the FastWriter. Here is the example usage:

from pyfastexcel import Workbook
from pyfastexcel.utils import set_custom_style

# CustomStyle will be integrate to the pyfatexcel in next version
# Beside, CustomStyle will be re-implement in future to make it no-longer
# depend on openpyxl_style writer and openpyxl
from openpyxl_style_writer import CustomStyle


if __name__ == '__main__':
    # Workbook
    wb = Workbook()

    # Set and register CustomStyle
    bold_style = CustomStyle(font_size=15, font_bold=True)
    set_custom_style('bold_style', bold_style)

    ws = wb['Sheet1']
    # Write value with default style
    ws['A1'] = 'A1 value'
    # Write value with custom style
    ws['B1'] = ('B1 value', 'bold_style')

    # Write value in slice with default style
    ws['A2': 'C2'] = [1, 2, 3]
    # Write value in slice with custom style
    ws['A3': 'C3'] = [(1, 'bold_style'), (2, 'bold_style'), (3, 'bold_style')]

    # Write value by row with default style (python index 0 is the index 1 in excel)
    ws[3] = [9, 8, 'go']
    # Write value by row with custom style
    ws[4] = [(9, 'bold_style'), (8, 'bold_style'), ('go', 'bold_style')]

    # Send request to golang lib and create excel
    wb.read_lib_and_create_excel()

    # File path to save
    file_path = 'pyexample_workbook.xlsx'
    wb.save(file_path)

You can also using the FastWriter or NormalWriter which was the subclass of Workbook to write excel row by row, see the following steps:

1. Create a class for your style registed like StyleCollections in the example.

2. Create a class for your excel creation implementation and inherit NormalWriter or FastWriter and StyleCollections.

3. Implement your data writing logic in def _create_body() and def _create_single_header()(The latter is not necessary)

from openpyxl_style_writer import CustomStyle
from openpyxl.styles import Side
from pyfastexcel.driver import FastWriter, NormalWriter


def prepare_example_data(rows: int = 1000, cols: int = 10) -> list[dict[str, str]]:
    import random

    random.seed(42)
    headers = [f'Column_{i}' for i in range(cols)]
    data = [[random.random() for _ in range(cols)] for _ in range(rows)]
    records = []
    for row in data:
        record = {}
        for header, value in zip(headers, row):
            record[header] = str(round(value * 100, 2))
        records.append(record)
    return records


class StyleCollections:
    black_fill_style = CustomStyle(
        font_size='11',
        font_bold=True,
        font_color='F62B00',
        fill_color='000000',
    )
    green_fill_style = CustomStyle(
        font_size='29',
        font_bold=False,
        font_color='000000',
        fill_color='375623',
    )
    test_fill_style = CustomStyle(
        font_params={
            'size': 20,
            'bold': True,
            'italic': True,
            'color': '5e03fc',
        },
        fill_params={
            'patternType': 'solid',
            'fgColor': '375623',
        },
        border_params={
            'left': Side(style='thin', color='e12aeb'),
            'right': Side(style='thick', color='e12aeb'),
            'top': Side(style=None, color='e12aeb'),
            'bottom': Side(style='dashDot', color='e12aeb'),
        },
        ali_params={
            'wrapText': True,
            'shrinkToFit': True,
        },
        number_format='0.00%',
    )


class PyExcelizeNormalExample(NormalWriter, StyleCollections):

    def create_excel(self) -> bytes:
        self._set_header()
        self._create_style()
        self.set_file_props('Creator', 'Hello')
        self._create_single_header()
        self._create_body()
        return self.read_lib_and_create_excel()

    def _set_header(self):
        self.headers = list(self.data[0].keys())

    def _create_single_header(self):
        for h in self.headers:
            self.row_append(h, style='green_fill_style')
        self.create_row()

    def _create_body(self) -> None:
        for row in self.data:
            for h in self.headers:
                if h[-1] in ('1', '3', '5', '7', '9'):
                    self.row_append(row[h], style='black_fill_style')
                else:
                    self.row_append(row[h], style='test_fill_style')
            self.create_row()

        self.switch_sheet('Sheet2')
        for row in self.data:
            for h in self.headers:
                if h[-1] in ('1', '3', '5', '7', '9'):
                    self.row_append(row[h], style=self.green_fill_style)
                else:
                    self.row_append(row[h], style='black_fill_style')
            self.create_row()

if __name__ == '__main__':
    data = prepare_example_data(653, 90)
    normal_writer = PyExcelizeFastExample(data)
    excel_normal = normal_writer.create_excel()
    file_path = 'pyexample_normal.xlsx'
    normal_writer.save('pyexample_normal.xlsx')

The example of FastWriter now supports index assignment. Please see the last few lines of code in _create_body() for reference.

from pyfastexcel.driver import FastWriter


class PyExcelizeFastExample(FastWriter, StyleCollections):

    def create_excel(self) -> bytes:
        self._set_header()
        self._create_style()
        self.set_file_props('Creator', 'Hello')
        self._create_single_header()
        self._create_body()
        return self.read_lib_and_create_excel()

    def _set_header(self):
        self.headers = list(self.data[0].keys())

    def _create_single_header(self):
        for h in self.headers:
            self.row_append(h, style='green_fill_style')
        self.create_row()

    def _create_body(self) -> None:
        for row in self.data:
            for h in self.headers:
                if h[-1] in ('1', '3', '5', '7', '9'):
                    self.row_append(row[h], style='black_fill_style')
                else:
                    self.row_append(row[h], style='test_fill_style')
            self.create_row()

        self.switch_sheet('Sheet2')
        for row in self.data:
            for h in self.headers:
                if h[-1] in ('1', '3', '5', '7', '9'):
                    self.row_append(row[h], style=self.green_fill_style)
                else:
                    self.row_append(row[h], style='black_fill_style')
            self.create_row()

        # Assigning a value with a specific style
        self.workbook['Sheet1']['A2'] = ('Hellow World', 'black_fill_style')

        # Assigning a value without specifying a style (default style used)
        self.workbook['Sheet1']['A3'] = 'I am A3'
        self.workbook['Sheet1']['AB9'] = 'GOGOGO'


if __name__ == '__main__':
    data = prepare_example_data(653, 90)
    normal_writer = PyExcelizeFastExample(data)
    excel_normal = normal_writer.create_excel()
    file_path = 'pyexample_normal.xlsx'
    normal_writer.save('pyexample_normal.xlsx')

Current Limitations & Future Plans

Problem 1: Dependence on Other Excel Package

Limitations:

This project currently depends on the CustomStyle object of the openpyxl_style_writer package, which is built for openpyxl to write styles in write-only mode more efficiently without duplicating code.

Future Plans:

This project plans to create its own Style object, making it no longer dependent on the mentioned package.