Field

Base class: Part

Class that describes a field, i.e. what input controls to render, the label, etc.

See Form for more complete examples.

The life cycle of the data is:

1. raw_data: will be set if the corresponding key is present in the HTTP request

2. parsed_data: set if parsing is successful, which only happens if the previous step succeeded

3. value: set if validation is successful, which only happens if the previous step succeeded

Note that, in addition to the parameters with the defined behavior below, you can pass in any keyword argument you need yourself, including callables that conform to the protocol, and they will be added and evaluated as members.

All these parameters can be callables, and if they are, will be evaluated with the keyword arguments form and field. The only exceptions are is_valid (which gets form, field and parsed_data), render_value (which takes form, field and value) and parse (which gets form, field, string_value). Example of using a lambda to specify a value:

Field(attrs__id=lambda form, field: 'my_id_%s' % field._name)

Refinable members

• after     (evaluated)

  Set the order of columns, see the howto for an example.

  Type: Union[int, str]

• assets

  Type: Namespace

• attr     (evaluated)

  The attribute path to apply or get the data from. For example using foo__bar__baz will result in your_instance.foo.bar.baz will be set by the apply() function. Defaults to same as name

  Type: str

• attrs     (evaluated)

  A dict containing any custom html attributes to be sent to the input__template.

  Type: Attrs

• choice_display_name_formatter

  Callback given the keyword argument choice in addition to standard parameters, to obtain the display name representing a given choice to the end user. Default implementation will use str(choice)

  Type: Callable[..., str]

  Default: lambda choice, **_: '%s' % choice

• choice_id_formatter

  Callback given the keyword argument choice in addition to standard parameters, to obtain the string value to represent the identity of a given choice. Default implementation will use str(choice)

  Type: Callable[..., str]

  Default: lambda choice, **_: '%s' % choice

• choice_to_optgroup

  Type: Union[Callable[..., Union[str, NoneType]], NoneType]

• choices     (evaluated)

  Type: Callable[..., List[Any]]

• display_name     (evaluated)

  The text in the HTML label tag. Default: capitalize(name).replace('_', ' ')

  Type: str

• editable     (evaluated)

  Is this field editable.

  Type: bool

  Default: True

• empty_label     (evaluated)

  Type: str

  Default: ---

• endpoints

  Type: Namespace

• errors

  Type: Errors

• extra

  Type: Dict[str, Any]

• extra_evaluated

  Type: Dict[str, Any]

• extra_params

• group     (evaluated)

  Type: str

• help

  Type: Fragment

• help_text

  The help text will be grabbed from the django model if specified and available.

• include     (evaluated)

  Type: bool

• initial     (evaluated)

  Initial value of the field

  Type: Any

• input

  Type: Fragment

• iommi_style

  Type: str

• is_boolean     (evaluated)

  Type: bool

  Default: False

• is_list     (evaluated)

  Interpret request data as a list (can NOT be a callable). Default: False`

  Type: bool

  Default: False

• is_valid

  Validation function. Should return a tuple of (bool, reason_for_failure_if_bool_is_false) or raise ValidationError.

form = Form.create(
    auto__model=Artist,
    fields__name__is_valid=lambda parsed_data, **_: (parsed_data.startswith('H'), 'Must start with H!'),
)

▼ Hide result

• label

  Type: Fragment

• model     (evaluated)

  Type: Union[Type[django.db.models.base.Model], NoneType]

• model_field

  Type: Union[django.db.models.fields.Field, NoneType]

• model_field_name

• non_editable_input

  Type: Fragment

  Default: {'call_target': <class 'iommi.fragment.Fragment'>, 'children__text': <function Field.<lambda> at 0x7f77d8c8e4d0>, 'attrs__value': <function Field.<lambda> at 0x7f77d8c8e560>, 'attrs__disabled': <function Field.<lambda> at 0x7f77d8c8e5f0>}

• parse

  Parse function. Default just returns the string input unchanged. This function can raise ValueError or ValidationError to produce a field error message.

• parse_empty_string_as_none     (evaluated)

  Type: bool

  Default: True

• parsed_data     (evaluated)

  Type: Any

• post_validation

• raw_data

  Type: str

• read_from_instance

  Callback to retrieve value from edited instance. Invoked with parameters field and instance.

• render_value

  Render the parsed and validated value into a string. Default just converts to str.

sentinel = '!!custom!!'
form = Form(
    fields__foo=Field(
        initial='not sentinel value',
        render_value=lambda form, field, value, **_: sentinel,
    )
)

▼ Hide result

• required     (evaluated)

  If the field is a required field. Default: True

  Type: bool

  Default: True

• search_fields

• strip_input     (evaluated)

  Runs the input data through standard python .strip() before passing it to the parse function (can NOT be callable). Default: True

  Type: bool

  Default: True

• tag     (evaluated)

  Type: str

  Default: div

• template     (evaluated)

  Django template filename or Template instance for the entire row. Normally you shouldn’t need to override on this level. Prefer overriding input__template, label__template or error__template as needed.

  Type: Union[str, iommi._web_compat.Template]

• write_to_instance

  Callback to write value to instance. Invoked with parameters field, instance and value.

Shortcuts

boolean

Defaults

• parse

  • iommi.form.bool_parse

• required

  • False

• is_boolean

  • True

boolean_tristate

Defaults

• choices

  • [True, False]

• choice_id_formatter

  • lambda choice, **_: 'true' if choice else 'false'

• choice_display_name_formatter

  • lambda choice, **_: gettext('Yes') if choice else gettext('No')

• parse

  • iommi.form.boolean_tristate__parse

• required

  • False

choice

Shortcut for single choice field. If required is false it will automatically add an option first with the value ‘’ and the title ‘—’. To override that text pass in the parameter empty_label.

Defaults

• required

  • True

• is_list

  • False

• is_valid

  • iommi.form.choice_is_valid

• input__attrs__multiple

  • lambda field, **_: True if field.is_list else None

• parse

  • iommi.form.choice_parse

choice_queryset

Defaults

• parse

  • iommi.form.choice_queryset__parse

• choice_id_formatter

  • lambda choice, **_: choice.pk

• endpoints__choices__func

  • iommi.form.choice_queryset__endpoint_handler

• is_valid

  • iommi.form.choice_queryset__is_valid

• extra__filter_and_sort

  • iommi.form.choice_queryset__extra__filter_and_sort

• extra__model_from_choices

  • iommi.form.choice_queryset__extra__model_from_choices

date

Defaults

• parse

  • iommi.form.date_parse

• render_value

  • iommi.form.date_render_value

datetime

Defaults

• parse

  • iommi.form.datetime_parse

• render_value

  • iommi.form.datetime_render_value

decimal

Defaults

• parse

  • iommi.form.decimal_parse

email

Defaults

• input__attrs__type

  • email

• parse

  • iommi.form.email_parse

file

Defaults

• input__attrs__type

  • file

• raw_data

  • iommi.form.file__raw_data

• write_to_instance

  • iommi.form.file_write_to_instance

float

Defaults

• parse

  • iommi.form.float_parse

foreign_key

foreign_key_reverse

Defaults

• editable

  • False

• display_name

  • lambda field, **_: capitalize(field.model_field.related_model._meta.verbose_name_plural)

• help_text

  • None

heading

Defaults

• editable

  • False

• attr

  • None

hidden

Defaults

• input__attrs__type

  • hidden

• attrs__style__display

  • none

image

Defaults

• template

  • iommi/form/image_row.html

info

Shortcut to create an info entry.

Defaults

• editable

  • False

• attr

  • None

integer

Defaults

• parse

  • iommi.form.int_parse

many_to_many

many_to_many_reverse

Defaults

• display_name

  • lambda field, **_: capitalize(field.model_field.remote_field.model._meta.verbose_name_plural)

• help_text

  • None

multi_choice

Defaults

• is_list

  • True

multi_choice_queryset

Defaults

• is_list

  • True

non_rendered

Defaults

• template

  • <iommi._web_compat.Template object at 0x7f77d8c98e10>

• editable

  • False

number

password

Defaults

• input__attrs__type

  • password

phone_number

Defaults

• is_valid

  • iommi.form.phone_number_is_valid

radio

Defaults

• input__attrs__id

  • None

• extra_evaluated__id

  • iommi.form.default_input_id

text

Defaults

• input__attrs__type

  • text

textarea

Defaults

• input__tag

  • textarea

• input__attrs__type

  • None

• input__attrs__value

  • None

• input__attrs__readonly

  • lambda field, **_: True if field.editable is False else None

• input__children__text

  • lambda field, **_: field.rendered_value

time

Defaults

• parse

  • iommi.form.time_parse

• render_value

  • iommi.form.time_render_value

url

Defaults

• input__attrs__type

  • url

• parse

  • iommi.form.url_parse

Methods

add_error

bind_from_instance

get_errors

on_bind

on_refine_done

own_evaluate_parameters

Class methods

from_model