angrybeanie_wagtail/env/lib/python3.12/site-packages/wagtail/fields.py

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2025-07-25 21:32:16 +10:00
import json
from django.core.serializers.json import DjangoJSONEncoder
from django.core.validators import MaxLengthValidator
from django.db import models
from django.utils.encoding import force_str
from django.utils.functional import cached_property
from wagtail.blocks import Block, BlockField, StreamBlock, StreamValue
from wagtail.blocks.definition_lookup import (
BlockDefinitionLookup,
BlockDefinitionLookupBuilder,
)
from wagtail.rich_text import (
RichTextMaxLengthValidator,
extract_references_from_rich_text,
get_text_for_indexing,
)
class RichTextField(models.TextField):
def __init__(self, *args, **kwargs):
# 'editor' and 'features' are popped before super().__init__ has chance to capture them
# for use in deconstruct(). This is intentional - they would not be useful in migrations
# and retrospectively adding them would generate unwanted migration noise
self.editor = kwargs.pop("editor", "default")
self.features = kwargs.pop("features", None)
super().__init__(*args, **kwargs)
def clone(self):
name, path, args, kwargs = self.deconstruct()
# add back the 'features' and 'editor' kwargs that were not preserved by deconstruct()
kwargs["features"] = self.features
kwargs["editor"] = self.editor
return self.__class__(*args, **kwargs)
def formfield(self, **kwargs):
from wagtail.admin.rich_text import get_rich_text_editor_widget
defaults = {
"widget": get_rich_text_editor_widget(self.editor, features=self.features)
}
defaults.update(kwargs)
field = super().formfield(**defaults)
# replace any MaxLengthValidators with RichTextMaxLengthValidators to ignore tags
for i, validator in enumerate(field.validators):
if isinstance(validator, MaxLengthValidator):
field.validators[i] = RichTextMaxLengthValidator(
validator.limit_value, message=validator.message
)
return field
def get_searchable_content(self, value):
# Strip HTML tags to prevent search backend from indexing them
source = force_str(value)
return [get_text_for_indexing(source)]
def extract_references(self, value):
yield from extract_references_from_rich_text(force_str(value))
# https://github.com/django/django/blob/64200c14e0072ba0ffef86da46b2ea82fd1e019a/django/db/models/fields/subclassing.py#L31-L44
class Creator:
"""
A placeholder class that provides a way to set the attribute on the model.
"""
def __init__(self, field):
self.field = field
def __get__(self, obj, type=None):
if obj is None:
return self
field_name = self.field.name
if field_name not in obj.__dict__:
# Field is deferred. Fetch it from db.
obj.refresh_from_db(fields=[field_name])
return obj.__dict__[field_name]
def __set__(self, obj, value):
obj.__dict__[self.field.name] = self.field.to_python(value)
class StreamField(models.Field):
def __init__(self, block_types, use_json_field=True, block_lookup=None, **kwargs):
"""
Construct a StreamField.
:param block_types: Either a list of block types that are allowed in this StreamField
(as a list of tuples of block name and block instance) or a StreamBlock to use as
the top level block (as a block instance or class).
:param use_json_field: Ignored, but retained for compatibility with historical migrations.
:param block_lookup: Used in migrations to provide a more compact block definition -
see ``wagtail.blocks.definition_lookup.BlockDefinitionLookup``. If passed, ``block_types``
can contain integer indexes into this lookup table, in place of actual block instances.
"""
# extract kwargs that are to be passed on to the block, not handled by super
self.block_opts = {}
for arg in ["min_num", "max_num", "block_counts", "collapsed"]:
if arg in kwargs:
self.block_opts[arg] = kwargs.pop(arg)
# for a top-level block, the 'blank' kwarg (defaulting to False) always overrides the
# block's own 'required' meta attribute, even if not passed explicitly; this ensures
# that the field and block have consistent definitions
self.block_opts["required"] = not kwargs.get("blank", False)
# Store the `block_types` and `block_lookup` arguments to be handled in the `stream_block`
# property
self.block_types_arg = block_types
self.block_lookup = block_lookup
super().__init__(**kwargs)
@cached_property
def stream_block(self):
has_block_lookup = self.block_lookup is not None
if has_block_lookup:
lookup = BlockDefinitionLookup(self.block_lookup)
if isinstance(self.block_types_arg, Block):
# use the passed block as the top-level block
block = self.block_types_arg
elif isinstance(self.block_types_arg, int) and has_block_lookup:
# retrieve block from lookup table to use as the top-level block
block = lookup.get_block(self.block_types_arg)
elif isinstance(self.block_types_arg, type):
# block passed as a class - instantiate it
block = self.block_types_arg()
else:
# construct a top-level StreamBlock from the list of block types.
# If an integer is found in place of a block instance, and block_lookup is
# provided, it will be replaced with the corresponding block definition.
child_blocks = []
for name, child_block in self.block_types_arg:
if isinstance(child_block, int) and has_block_lookup:
child_blocks.append((name, lookup.get_block(child_block)))
else:
child_blocks.append((name, child_block))
block = StreamBlock(child_blocks)
block.set_meta_options(self.block_opts)
return block
@property
def json_field(self):
return models.JSONField(encoder=DjangoJSONEncoder)
def get_internal_type(self):
return "JSONField"
def get_lookup(self, lookup_name):
return self.json_field.get_lookup(lookup_name)
def get_transform(self, lookup_name):
return self.json_field.get_transform(lookup_name)
def deconstruct(self):
name, path, _, kwargs = super().deconstruct()
lookup = BlockDefinitionLookupBuilder()
block_types = [
(name, lookup.add_block(block))
for name, block in self.stream_block.child_blocks.items()
]
args = [block_types]
kwargs["block_lookup"] = lookup.get_lookup_as_dict()
return name, path, args, kwargs
def to_python(self, value):
result = self.stream_block.to_python(value)
# The top-level StreamValue is passed a reference to the StreamField, to support
# pickling. This is necessary because unpickling needs access to the StreamBlock
# definition, which cannot itself be pickled; instead we store a pointer to the
# field within the model, which gives us a path to retrieve the StreamBlock definition.
result._stream_field = self
return result
def get_prep_value(self, value):
value = super().get_prep_value(value)
if (
isinstance(value, StreamValue)
and not (value)
and value.raw_text is not None
):
# An empty StreamValue with a nonempty raw_text attribute should have that
# raw_text attribute written back to the db. (This is probably only useful
# for reverse migrations that convert StreamField data back into plain text
# fields.)
return value.raw_text
elif isinstance(value, StreamValue):
# StreamValue instances must be prepared first.
return self.stream_block.get_prep_value(value)
else:
# If the value is not a StreamValue, it's likely the field is being
# used in a non-Wagtail context, e.g. in queries with JSONField features.
return super().get_prep_value(value)
def get_db_prep_value(self, value, connection, prepared=False):
# Use JSONField's get_db_prep_value method to handle the serialization,
# which may differ between database backends. However, use our own
# get_prep_value method to ensure that StreamValue instances are prepared
# before being passed to JSONField.
if not prepared:
value = self.get_prep_value(value)
return self.json_field.get_db_prep_value(
value, connection=connection, prepared=True
)
def from_db_value(self, value, expression, connection):
# Historically, StreamField's deserialization used to be handled by
# to_python, which in turn handled by BaseStreamBlock.to_python. This was
# always the case even before and after the use of the JSON data type.
# However, now that we can be confident all StreamField data has been
# migrated to use JSON in the database, we can reuse any special handling
# that JSONField.from_db_value provides, e.g. for handling KeyTransforms
# on SQLite.
# This means we are passing a deserialized value to StreamBlock.to_python,
# which is a change from the previous behaviour. However, this is fine
# because to_python can handle both serialized and deserialized values.
value = self.json_field.from_db_value(value, expression, connection)
return self.to_python(value)
def formfield(self, **kwargs):
"""
Override formfield to use a plain forms.Field so that we do no transformation on the value
(as distinct from the usual fallback of forms.CharField, which transforms it into a string).
"""
defaults = {"form_class": BlockField, "block": self.stream_block}
defaults.update(kwargs)
return super().formfield(**defaults)
def get_default(self):
return self.stream_block.normalize(super().get_default())
def value_to_string(self, obj):
# This method is used for serialization using django.core.serializers,
# which is used by dumpdata and loaddata for serializing model objects.
# Unlike other fields, JSONField only uses value_from_object without
# doing the actual serialization, so that it doesn't end up being
# double-serialized when the model object is serialized.
# Unfortunately, this is also used by django-modelcluster, which is used
# to serialize model objects to be stored in revisions. When we migrated
# StreamField to use the JSON data type, we did not change this method's
# behaviour, i.e. it still returns a JSON-shaped string, to ensure that
# revisions are still saved in the same format as before even if it
# means StreamField inside the revision data becomes double-serialized.
# Now that we change get_prep_value to not do the serialization in favor
# of get_db_prep_value, we need to add the serialization here too.
value = self.value_from_object(obj)
return json.dumps(self.get_prep_value(value), cls=self.json_field.encoder)
def get_searchable_content(self, value):
return self.stream_block.get_searchable_content(value)
def extract_references(self, value):
yield from self.stream_block.extract_references(value)
def get_block_by_content_path(self, value, path_elements):
"""
Given a list of elements from a content path, retrieve the block at that path
as a BoundBlock object, or None if the path does not correspond to a valid block.
"""
return self.stream_block.get_block_by_content_path(value, path_elements)
def check(self, **kwargs):
errors = super().check(**kwargs)
errors.extend(self.stream_block.check(field=self, **kwargs))
return errors
def contribute_to_class(self, cls, name, **kwargs):
super().contribute_to_class(cls, name, **kwargs)
# Add Creator descriptor to allow the field to be set from a list or a
# JSON string.
setattr(cls, self.name, Creator(self))