In most of the cases, you need to export the data from your database to different formats. In this post I will show you how to create functions in your Django applications which export data as files. Here I will be covering the mostly used formats: CSV and Excel.
First of all, look at the model.
from django.db import models class Book(models.Model): title = models.CharField(max_length=100) description = models.TextField(blank=True)
It's a simple model with title and description. Now lets create the functions.
CSV is the most common import and export format for databases.It's a textual format. Python comes with a built-in CSV library called csv.
import csv from django.http import HttpResponse from app_name.models import Book def generate_book_csv(request): books = Book.objects.all() # Create the HttpResponse object with CSV header.This tells browsers that # the document is a CSV file. response = HttpResponse(content_type='text/csv') # The response also has additional Content-Disposition header, which contains # the name of the CSV file. response['Content-Disposition'] = 'attachment; filename=books.csv' # The csv.writer function takes file-like object as argument i.e.,HttpResponse object writer = csv.writer(response) # For each row in your CSV file, call writer.writerow function by passing # a list or tuple to it. writer.writerow(['ID', 'Title', 'Description']) for book in books: writer.writerow([book.id, book.title, book.description]) return response
Finally return the response object.
Excel is the main spreadsheet format which holds data in worksheets, charts etc. We are going to use xlwt library to create a spreadsheet.
First you need to install xlwt library using the command - pip install xlwt
import xlwt from django.http import HttpResponse from app_name.models import Book def generate_book_excel(request): books = Book.objects.all() # Create the HttpResponse object with Excel header.This tells browsers that # the document is a Excel file. response = HttpResponse(content_type='application/ms-excel') # The response also has additional Content-Disposition header, which contains # the name of the Excel file. response['Content-Disposition'] = 'attachment; filename=books.xls' # Create object for the Workbook which is under xlwt library. workbook = xlwt.Workbook() # By using Workbook object, add the sheet with the name of your choice. worksheet = workbook.add_sheet("Books") row_num = 0 columns = ['ID', 'Title', 'Description'] for col_num in range(len(columns)): # For each cell in your Excel Sheet, call write function by passing row number, # column number and cell data. worksheet.write(row_num, col_num, columns[col_num]) for book in books: row_num += 1 row = [book.id,book.title,book.description] for col_num in range(len(row)): worksheet.write(row_num, col_num, row[col_num]) workbook.save(response) return response
After filling up the sheet with the data, save the workbook by passing response object as an argument and return response object. Finally the response will be Excel file(books.xls) with all the records in the Book Model.