How to Use django-adaptors

Django-adaptors is a valuable Django application that streamlines data import and export processes between various file formats and your Django models. It provides a flexible and efficient way to manage data exchange in your Django projects. This guide will explain how to install and use django-adaptors to import data from CSV files and export data to CSV files.

Installation

To get started, install django-adaptors using pip:

pip install django-adaptors

Next, add ‘django-adaptors’ to your INSTALLED_APPS list in your project’s settings.py file:

# settings.py

INSTALLED_APPS = [
# ...
'django_adaptors',
# ...
]

Importing Data from CSV

Let’s walk through an example of importing data from a CSV file into a Django model using django-adaptors.

1. Define Your Django Model

First, create your Django model. Here’s a simple example of a Person model:

# models.py

from django.db import models

class Person(models.Model):
    first_name = models.CharField(max_length=30)
    last_name = models.CharField(max_length=30)
    email = models.EmailField(unique=True)

    def __str__(self):
        return f"{self.first_name} {self.last_name}"

2. Create a CSV Adapter

We’ll create a CSV adapter class to map the CSV file’s fields to the corresponding fields in your model. This adapter tells django-adaptors how to interpret the data in the CSV file.

# adapters.py

from django_adaptors import models
from .models import Person

class PersonCSVAdapter(models.CsvDbModel):
    class Meta:
        dbModel = Person
        delimiter = ';'  # Adjust this if your CSV uses a different delimiter
        has_header = True  # Set to False if your CSV file has no header row
        mapping = {
            'first_name': 'FirstName',
            'last_name': 'LastName',
            'email': 'Email',
        }

Here’s a breakdown of the code:

dbModel: Specifies the Django model to which data will be imported.
delimiter: The delimiter used in your CSV file (e.g., comma, semicolon).
has_header: Indicates if the CSV file has a header row.
mapping: A dictionary that maps model fields (keys) to CSV column headers (values).

Import Data

Now, you can import data from a CSV file into your model:

# import_data.py

from .adapters import PersonCSVAdapter

# Read CSV data from a file
with open('people.csv', 'r') as csv_file:
    content = csv_file.read()

# Import data using the adapter
result = PersonCSVAdapter.import_from_string(content)

# Check for errors
    if result.errors:
        print("Errors occurred during import:")
        for error in result.errors:
            print(error)
    else:
        print(f"Successfully imported {len(result.cleaned_objects)} records.")

Exporting Data to CSV

You can also export data from your Django models to a CSV file using django-adaptors.

Create an Export Adapter

Define a CSV adapter for exporting data:

# adapters.py (add to existing code)

    class PersonCSVExporter(models.CsvModel):
        first_name = models.CharField()
        last_name = models.CharField()
        email = models.EmailField()

        class Meta:
            delimiter = ';'
            has_header = True

Export Data

Use the exporter to write data to a CSV file:

# export_data.py

    from .adapters import PersonCSVExporter
    from .models import Person

    # Query the data you want to export
    people = Person.objects.all()

    # Convert queryset to CSV string
    csv_data = PersonCSVExporter.export_csv(people)

    # Write to a CSV file
    with open('exported_people.csv', 'w') as csv_file:
        csv_file.write(csv_data)

Handling Import Errors

django-adaptors provides mechanisms to handle errors during data import. When calling import_from_string(), it returns a result object containing:

errors: A list of errors encountered during import.
cleaned_objects: A list of successfully imported objects.

You can use this information to log errors or take corrective actions.

Importing Data from Other Formats

While this guide focuses on CSV files, django-adaptors also supports other data formats like XML. You can create adapters similar to the CSV adapter for different formats by extending the appropriate classes provided by django-adaptors.