Python django.forms.FileField() Examples

def field_value(field):
	""" 
	Returns the value for this BoundField, as rendered in widgets. 
	""" 
	if field.form.is_bound: 
		if isinstance(field.field, FileField) and field.data is None: 
			val = field.form.initial.get(field.name, field.field.initial) 
		else: 
			val = field.data 
	else:
		val = field.form.initial.get(field.name, field.field.initial)
		if isinstance(val, collections.Callable):
			val = val()
	if val is None:
		val = ''
	return val 

def clean(self, value, initial):
        files = value['files']
        cleared = value['cleared']
        if not files and not cleared:
            return initial
        new = [
            FileField(validators=[
                FileExtensionValidator(allowed_extensions=settings.FILE_ALLOWED_EXTENSIONS)
            ]).clean(file, initial) for file in files
        ]

        if initial:
            old = [file for i, file in enumerate(initial) if i not in cleared]
        else:
            old = []

        return old + new 

def process_form_submission(self, form):
        cleaned_data = form.cleaned_data

        for name, field in form.fields.items():
            if isinstance(field, FileField):
                file_data = cleaned_data[name]
                if file_data:
                    file_name = file_data.name
                    file_name = webform_storage.generate_filename(file_name)
                    upload_to = os.path.join('webform', str(self.id), file_name)
                    saved_file_name = webform_storage.save(upload_to, file_data)
                    file_details_dict = {name: webform_storage.url(saved_file_name)}
                    cleaned_data.update(file_details_dict)
                else:
                    del cleaned_data[name]

        form_data = json.dumps(cleaned_data, cls=DjangoJSONEncoder)
        return self.get_submission_class().objects.create(
            form_data=form_data,
            page=self,
        ) 

def test_full_clear(self):
        """
        Integration happy-path test that a model FileField can actually be set
        and cleared via a ModelForm.
        """
        class DocumentForm(forms.ModelForm):
            class Meta:
                model = Document
                fields = '__all__'

        form = DocumentForm()
        self.assertIn('name="myfile"', str(form))
        self.assertNotIn('myfile-clear', str(form))
        form = DocumentForm(files={'myfile': SimpleUploadedFile('something.txt', b'content')})
        self.assertTrue(form.is_valid())
        doc = form.save(commit=False)
        self.assertEqual(doc.myfile.name, 'something.txt')
        form = DocumentForm(instance=doc)
        self.assertIn('myfile-clear', str(form))
        form = DocumentForm(instance=doc, data={'myfile-clear': 'true'})
        doc = form.save(commit=False)
        self.assertFalse(doc.myfile) 

def test_filefield_changed(self):
        """
        The value of data will more than likely come from request.FILES. The
        value of initial data will likely be a filename stored in the database.
        Since its value is of no use to a FileField it is ignored.
        """
        f = FileField()

        # No file was uploaded and no initial data.
        self.assertFalse(f.has_changed('', None))

        # A file was uploaded and no initial data.
        self.assertTrue(f.has_changed('', {'filename': 'resume.txt', 'content': 'My resume'}))

        # A file was not uploaded, but there is initial data
        self.assertFalse(f.has_changed('resume.txt', None))

        # A file was uploaded and there is initial data (file identity is not dealt
        # with here)
        self.assertTrue(f.has_changed('resume.txt', {'filename': 'resume.txt', 'content': 'My resume'})) 

def test_disabled_has_changed(self):
        f = FileField(disabled=True)
        self.assertIs(f.has_changed('x', 'y'), False) 

def test_filefield_3(self):
        f = FileField(allow_empty_file=True)
        self.assertIsInstance(f.clean(SimpleUploadedFile('name', b'')), SimpleUploadedFile) 

def deconstruct(self):
        name, path, args, kwargs = super(FileField, self).deconstruct()
        if kwargs.get("max_length") == 100:
            del kwargs["max_length"]
        kwargs['upload_to'] = self.upload_to
        if self.storage is not default_storage:
            kwargs['storage'] = self.storage
        return name, path, args, kwargs 

def test_clean_false_required(self):
        """
        If the ``clean`` method on a required FileField receives False as the
        data, it has the same effect as None: initial is returned if non-empty,
        otherwise the validation catches the lack of a required value.
        """
        f = forms.FileField(required=True)
        self.assertEqual(f.clean(False, 'initial'), 'initial')
        with self.assertRaises(ValidationError):
            f.clean(False) 

def test_clean_false(self):
        """
        If the ``clean`` method on a non-required FileField receives False as
        the data (meaning clear the field value), it returns False, regardless
        of the value of ``initial``.
        """
        f = forms.FileField(required=False)
        self.assertIs(f.clean(False), False)
        self.assertIs(f.clean(False, 'initial'), False) 

def create_document_field(self, field, options):
        return FileField(**options) 

def get_form_field(self, **kwargs):
    """Return a Django form field appropriate for a blob property.

    This defaults to a forms.FileField instance when using Django 0.97
    or later.  For 0.96 this returns None, as file uploads are not
    really supported in that version.
    """
    if not hasattr(forms, 'FileField'):
      return None
    defaults = {'form_class': forms.FileField}
    defaults.update(kwargs)
    return super(BlobProperty, self).get_form_field(**defaults) 

def make_value_from_form(self, value):
    """Convert a form value to a property value.

    This extracts the content from the UploadedFile instance returned
    by the FileField instance.
    """
    if have_uploadedfile and isinstance(value, uploadedfile.UploadedFile):
      if not self.form_value:
        self.form_value = value.read()
      b = db.Blob(self.form_value)
      return b
    return super(BlobProperty, self).make_value_from_form(value) 

def test_filefield_required_false(self):
        # Test the non-required FileField
        f = TextFileForm(data={'description': 'Assistance'})
        f.fields['file'].required = False
        self.assertTrue(f.is_valid())
        instance = f.save()
        self.assertEqual(instance.file.name, '')

        f = TextFileForm(
            data={'description': 'Assistance'},
            files={'file': SimpleUploadedFile('test3.txt', b'hello world')},
            instance=instance,
        )
        self.assertTrue(f.is_valid())
        instance = f.save()
        self.assertEqual(instance.file.name, 'tests/test3.txt')

        # Instance can be edited w/out re-uploading the file and existing file should be preserved.
        f = TextFileForm({'description': 'New Description'}, instance=instance)
        f.fields['file'].required = False
        self.assertTrue(f.is_valid())
        instance = f.save()
        self.assertEqual(instance.description, 'New Description')
        self.assertEqual(instance.file.name, 'tests/test3.txt')

        # Delete the current file since this is not done by Django.
        instance.file.delete()
        instance.delete() 

def __eq__(self, other):
        # Older code may be expecting FileField values to be simple strings.
        # By overriding the == operator, it can remain backwards compatibility.
        if hasattr(other, 'name'):
            return self.name == other.name
        return self.name == other 

def __set__(self, instance, value):
        previous_file = instance.__dict__.get(self.field.name)
        super(ImageFileDescriptor, self).__set__(instance, value)

        # To prevent recalculating image dimensions when we are instantiating
        # an object from the database (bug #11084), only update dimensions if
        # the field had a value before this assignment.  Since the default
        # value for FileField subclasses is an instance of field.attr_class,
        # previous_file will only be None when we are called from
        # Model.__init__().  The ImageField.update_dimension_fields method
        # hooked up to the post_init signal handles the Model.__init__() cases.
        # Assignment happening outside of Model.__init__() will trigger the
        # update right here.
        if previous_file is not None:
            self.field.update_dimension_fields(instance, force=True) 

def formfield(self, **kwargs):
        defaults = {'form_class': forms.FileField, 'max_length': self.max_length}
        # If a file has been provided previously, then the form doesn't require
        # that a new file is provided this time.
        # The code to mark the form field as not required is used by
        # form_for_instance, but can probably be removed once form_for_instance
        # is gone. ModelForm uses a different method to check for an existing file.
        if 'initial' in kwargs:
            defaults['required'] = False
        defaults.update(kwargs)
        return super(FileField, self).formfield(**defaults) 

def contribute_to_class(self, cls, name, **kwargs):
        super(FileField, self).contribute_to_class(cls, name, **kwargs)
        setattr(cls, self.name, self.descriptor_class(self)) 

def pre_save(self, model_instance, add):
        "Returns field's value just before saving."
        file = super(FileField, self).pre_save(model_instance, add)
        if file and not file._committed:
            # Commit the file to storage prior to saving the model
            file.save(file.name, file, save=False)
        return file 

def get_prep_value(self, value):
        "Returns field's value prepared for saving into a database."
        value = super(FileField, self).get_prep_value(value)
        # Need to convert File objects provided via a form to unicode for database insertion
        if value is None:
            return None
        return six.text_type(value) 

def get_internal_type(self):
        return "FileField" 

def deconstruct(self):
        name, path, args, kwargs = super(FileField, self).deconstruct()
        if kwargs.get("max_length") == 100:
            del kwargs["max_length"]
        kwargs['upload_to'] = self.upload_to
        if self.storage is not default_storage:
            kwargs['storage'] = self.storage
        return name, path, args, kwargs 

def check(self, **kwargs):
        errors = super(FileField, self).check(**kwargs)
        errors.extend(self._check_unique())
        errors.extend(self._check_primary_key())
        return errors 

def __init__(self, verbose_name=None, name=None, upload_to='', storage=None, **kwargs):
        self._primary_key_set_explicitly = 'primary_key' in kwargs
        self._unique_set_explicitly = 'unique' in kwargs

        self.storage = storage or default_storage
        self.upload_to = upload_to

        kwargs['max_length'] = kwargs.get('max_length', 100)
        super(FileField, self).__init__(verbose_name, name, **kwargs) 

def __eq__(self, other):
        # Older code may be expecting FileField values to be simple strings.
        # By overriding the == operator, it can remain backwards compatibility.
        if hasattr(other, 'name'):
            return self.name == other.name
        return self.name == other 

def __set__(self, instance, value):
        previous_file = instance.__dict__.get(self.field.name)
        super(ImageFileDescriptor, self).__set__(instance, value)

        # To prevent recalculating image dimensions when we are instantiating
        # an object from the database (bug #11084), only update dimensions if
        # the field had a value before this assignment.  Since the default
        # value for FileField subclasses is an instance of field.attr_class,
        # previous_file will only be None when we are called from
        # Model.__init__().  The ImageField.update_dimension_fields method
        # hooked up to the post_init signal handles the Model.__init__() cases.
        # Assignment happening outside of Model.__init__() will trigger the
        # update right here.
        if previous_file is not None:
            self.field.update_dimension_fields(instance, force=True) 

def formfield(self, **kwargs):
        defaults = {'form_class': forms.FileField, 'max_length': self.max_length}
        # If a file has been provided previously, then the form doesn't require
        # that a new file is provided this time.
        # The code to mark the form field as not required is used by
        # form_for_instance, but can probably be removed once form_for_instance
        # is gone. ModelForm uses a different method to check for an existing file.
        if 'initial' in kwargs:
            defaults['required'] = False
        defaults.update(kwargs)
        return super(FileField, self).formfield(**defaults) 

def pre_save(self, model_instance, add):
        "Returns field's value just before saving."
        file = super(FileField, self).pre_save(model_instance, add)
        if file and not file._committed:
            # Commit the file to storage prior to saving the model
            file.save(file.name, file, save=False)
        return file 

def get_prep_lookup(self, lookup_type, value):
        if hasattr(value, 'name'):
            value = value.name
        return super(FileField, self).get_prep_lookup(lookup_type, value) 

def get_internal_type(self):
        return "FileField"