Getting started

For example purposes, we’ll use a simplified book app. Here is our models.py:

# app/models.py

class Author(models.Model):
    name = models.CharField(max_length=100)

    def __unicode__(self):
        return self.name


class Category(models.Model):
    name = models.CharField(max_length=100)

    def __unicode__(self):
        return self.name


class Book(models.Model):
    name = models.CharField('Book name', max_length=100)
    author = models.ForeignKey(Author, blank=True, null=True)
    author_email = models.EmailField('Author email', max_length=75, blank=True)
    imported = models.BooleanField(default=False)
    published = models.DateField('Published', blank=True, null=True)
    price = models.DecimalField(max_digits=10, decimal_places=2, null=True, blank=True)
    categories = models.ManyToManyField(Category, blank=True)

    def __unicode__(self):
        return self.name

Creating import-export resource

To integrate django-import-export with our Book model, we will create a ModelResource class in admin.py that will describe how this resource can be imported or exported:

# app/admin.py

from import_export import resources
from core.models import Book

class BookResource(resources.ModelResource):

    class Meta:
        model = Book

Exporting data

Now that we have defined a ModelResource class, we can export books:

>>> from app.admin import BookResource
>>> dataset = BookResource().export()
>>> print dataset.csv
id,name,author,author_email,imported,published,price,categories
2,Some book,1,,0,2012-12-05,8.85,1

Customize resource options

By default ModelResource introspects model fields and creates Field-attributes with an appropriate Widget for each field.

To affect which model fields will be included in an import-export resource, use the fields option to whitelist fields:

class BookResource(resources.ModelResource):

    class Meta:
        model = Book
        fields = ('id', 'name', 'price',)

Or the exclude option to blacklist fields:

class BookResource(resources.ModelResource):

    class Meta:
        model = Book
        exclude = ('imported', )

An explicit order for exporting fields can be set using the export_order option:

class BookResource(resources.ModelResource):

    class Meta:
        model = Book
        fields = ('id', 'name', 'author', 'price',)
        export_order = ('id', 'price', 'author', 'name')

The default field for object identification is id, you can optionally set which fields are used as the id when importing:

class BookResource(resources.ModelResource):

    class Meta:
        model = Book
        import_id_fields = ('isbn',)
        fields = ('isbn', 'name', 'author', 'price',)

When defining ModelResource fields it is possible to follow model relationships:

class BookResource(resources.ModelResource):

    class Meta:
        model = Book
        fields = ('author__name',)

Note

Following relationship fields sets field as readonly, meaning this field will be skipped when importing data.

By default all records will be imported, even if no changes are detected. This can be changed setting the skip_unchanged option. Also, the report_skipped option controls whether skipped records appear in the import Result object, and if using the admin whether skipped records will show in the import preview page:

class BookResource(resources.ModelResource):

    class Meta:
        model = Book
        skip_unchanged = True
        report_skipped = False
        fields = ('id', 'name', 'price',)

See also

Resources

Declaring fields

It is possible to override a resource field to change some of its options:

from import_export import fields

class BookResource(resources.ModelResource):
    published = fields.Field(column_name='published_date')

    class Meta:
        model = Book

Other fields that don’t exist in the target model may be added:

from import_export import fields

class BookResource(resources.ModelResource):
    myfield = fields.Field(column_name='myfield')

    class Meta:
        model = Book

See also

Fields
Available field types and options.

Advanced data manipulation

Not all data can be easily extracted from an object/model attribute. In order to turn complicated data model into a (generally simpler) processed data structure, dehydrate_<fieldname> method should be defined:

from import_export import fields

class BookResource(resources.ModelResource):
    full_title = fields.Field()

    class Meta:
        model = Book

    def dehydrate_full_title(self, book):
        return '%s by %s' % (book.name, book.author.name)

Customize widgets

A ModelResource creates a field with a default widget for a given field type. If the widget should be initialized with different arguments, set the widgets dict.

In this example widget, the published field is overriden to use a different date format. This format will be used both for importing and exporting resource.

class BookResource(resources.ModelResource):

    class Meta:
        model = Book
        widgets = {
                'published': {'format': '%d.%m.%Y'},
                }

See also

Widgets
available widget types and options.

Importing data

Let’s import some data!

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>>> import tablib
>>> from import_export import resources
>>> from core.models import Book
>>> book_resource = resources.modelresource_factory(model=Book)()
>>> dataset = tablib.Dataset(['', 'New book'], headers=['id', 'name'])
>>> result = book_resource.import_data(dataset, dry_run=True)
>>> print result.has_errors()
False
>>> result = book_resource.import_data(dataset, dry_run=False)

In the fourth line we use modelresource_factory() to create a default ModelResource. The ModelResource class created this way is equal to the one shown in the example in section Creating import-export resource.

In fifth line a Dataset with columns id and name, and one book entry, are created. A field for a primary key field (in this case, id) always needs to be present.

In the rest of the code we first pretend to import data using import_data() and dry_run set, then check for any errors and actually import data this time.

See also

Import data workflow
for a detailed description of the import workflow and its customization options.

Deleting data

To delete objects during import, implement the for_delete() method on your Resource class.

The following is an example resource which expects a delete field in the dataset. An import using this resource will delete model instances for rows that have their column delete set to 1:

class BookResource(resources.ModelResource):
    delete = fields.Field(widget=widgets.BooleanWidget())

    def for_delete(self, row, instance):
        return self.fields['delete'].clean(row)

    class Meta:
        model = Book

Signals

To hook in the import export workflow, you can connect to post_import, post_export signals:

from django.dispatch import receiver from import_export.signals import post_import, post_export

@receiver(post_import, dispatch_uid=’balabala...’) def _post_import(model, **kwargs):

# model is the actual model instance which after import pass

@receiver(post_export, dispatch_uid=’balabala...’) def _post_export(model, **kwargs):

# model is the actual model instance which after export pass

Admin integration

Exporting via list filters

Admin integration is achieved by subclassing ImportExportModelAdmin or one of the available mixins (ImportMixin, ExportMixin, ImportExportMixin):

# app/admin.py
from import_export.admin import ImportExportModelAdmin

class BookAdmin(ImportExportModelAdmin):
    resource_class = BookResource
_images/django-import-export-change.png

A screenshot of the change view with Import and Export buttons.

_images/django-import-export-import.png

A screenshot of the import view.

_images/django-import-export-import-confirm.png

A screenshot of the confirm import view.

Exporting via admin action

Another approach to exporting data is by subclassing ImportExportActionModelAdmin which implements export as an admin action. As a result it’s possible to export a list of objects selected on the change list page:

# app/admin.py
from import_export.admin import ImportExportActionModelAdmin

class BookAdmin(ImportExportActionModelAdmin):
    pass
_images/django-import-export-action.png

A screenshot of the change view with Import and Export as an admin action.

See also

Admin
available mixins and options.