def test_ordering():
"""
FrozenDict should preserve ordering
"""
f = FrozenDict([('a', 1), ('b', 2)])
assert list(f.items()) == [('a', 1), ('b', 2)]
class VDOM(object):
"""A basic virtual DOM class which allows you to write literal VDOM spec
>>> VDOM(tag_name='h1', children='Hey', attributes: {}})
>>> from vdom.helpers import h1
>>> h1('Hey')
"""
# This class should only have these 5 attributes
__slots__ = [
'tag_name', 'attributes', 'style', 'children', 'key', 'event_handlers',
'_frozen'
]
def __init__(
self,
tag_name,
attributes=None,
style=None,
children=None,
key=None,
event_handlers=None,
schema=None,
):
if isinstance(tag_name, dict) or isinstance(tag_name, list):
# Backwards compatible interface
warnings.warn('Passing dict to VDOM constructor is deprecated')
value = tag_name
vdom_obj = VDOM.from_dict(value)
tag_name = vdom_obj.tag_name
style = vdom_obj.style
event_handlers = vdom_obj.event_handlers
attributes = vdom_obj.attributes
children = vdom_obj.children
key = vdom_obj.key
self.tag_name = tag_name
# Sort attributes so our outputs are predictable
self.attributes = FrozenDict(sorted(
attributes.items())) if attributes else FrozenDict()
self.children = tuple(children) if children else tuple()
self.key = key
# Sort attributes so our outputs are predictable
self.style = FrozenDict(sorted(
style.items())) if style else FrozenDict()
self.event_handlers = (FrozenDict(sorted(event_handlers.items()))
if event_handlers else FrozenDict())
# Validate that all children are VDOMs or strings
if not all(
isinstance(c, (VDOM, string_types[:])) for c in self.children):
raise ValueError(
'Children must be a list of VDOM objects or strings')
# All style keys & values must be strings
if not all(
isinstance(k, string_types) and isinstance(v, string_types)
for k, v in self.style.items()):
raise ValueError('Style must be a dict with string keys & values')
# mark completion of object creation. Object is immutable from now.
self._frozen = True
if schema is not None:
self.validate(schema)
def __setattr__(self, attr, value):
"""
Make instances immutable after creation
"""
if hasattr(self, '_frozen') and self._frozen:
raise AttributeError("Cannot change attribute of immutable object")
super(VDOM, self).__setattr__(attr, value)
def validate(self, schema):
"""
Validate VDOM against given JSON Schema
Raises ValidationError if schema does not match
"""
try:
validate(instance=self.to_dict(),
schema=schema,
cls=Draft4Validator)
except ValidationError as e:
raise ValidationError(_validate_err_template.format(
VDOM_SCHEMA, e))
def to_dict(self):
"""Converts VDOM object to a dictionary that passes our schema
"""
attributes = dict(self.attributes.items())
if self.style:
attributes.update({"style": dict(self.style.items())})
vdom_dict = {'tagName': self.tag_name, 'attributes': attributes}
if self.event_handlers:
event_handlers = dict(self.event_handlers.items())
for key, value in event_handlers.items():
value = create_event_handler(key, value)
event_handlers[key] = value
vdom_dict['eventHandlers'] = event_handlers
if self.key:
vdom_dict['key'] = self.key
vdom_dict['children'] = [
c.to_dict() if isinstance(c, VDOM) else c for c in self.children
]
return vdom_dict
def to_json(self):
return json.dumps(self.to_dict())
def to_html(self):
return self._repr_html_()
def json_contents(self):
warnings.warn(
'VDOM.json_contents method is deprecated, use to_json instead')
return self.to_json()
def _to_inline_css(self, style):
"""
Return inline CSS from CSS key / values
"""
return "; ".join([
'{}: {}'.format(convert_style_key(k), v) for k, v in style.items()
])
def _repr_html_(self):
"""
Return HTML representation of VDOM object.
HTML escaping is performed wherever necessary.
"""
# Use StringIO to avoid a large number of memory allocations with string concat
with io.StringIO() as out:
out.write('<{tag}'.format(tag=escape(self.tag_name)))
if self.style:
# Important values are in double quotes - cgi.escape only escapes double quotes, not single quotes!
out.write(' style="{css}"'.format(
css=escape(self._to_inline_css(self.style))))
for k, v in self.attributes.items():
# Important values are in double quotes - cgi.escape only escapes double quotes, not single quotes!
if isinstance(v, string_types):
out.write(' {key}="{value}"'.format(key=escape(k),
value=escape(v)))
if isinstance(v, bool) and v:
out.write(' {key}'.format(key=escape(k)))
out.write('>')
for c in self.children:
if isinstance(c, string_types):
out.write(escape(safe_unicode(c)))
else:
out.write(c._repr_html_())
out.write('</{tag}>'.format(tag=escape(self.tag_name)))
return out.getvalue()
def _repr_mimebundle_(self, include=None, exclude=None, **kwargs):
return {
'application/vdom.v1+json': self.to_dict(),
'text/plain': self.to_html()
}
@classmethod
def from_dict(cls, value):
try:
validate(instance=value, schema=VDOM_SCHEMA, cls=Draft4Validator)
except ValidationError as e:
raise ValidationError(_validate_err_template.format(
VDOM_SCHEMA, e))
attributes = value.get('attributes', {})
style = None
event_handlers = None
if 'style' in attributes:
# Make a copy of attributes, since we're gonna remove styles from it
attributes = attributes.copy()
style = attributes.pop('style')
for key, val in attributes.items():
if callable(val):
attributes = attributes.copy()
if event_handlers == None:
event_handlers = {key: attributes.pop(key)}
else:
event_handlers[key] = attributes.pop(key)
return cls(
tag_name=value['tagName'],
attributes=attributes,
style=style,
event_handlers=event_handlers,
children=[
VDOM.from_dict(c) if isinstance(c, dict) else c
for c in value.get('children', [])
],
key=value.get('key'),
)
class VDOM(object):
"""A basic virtual DOM class which allows you to write literal VDOM spec
>>> VDOM(tag_name='h1', children='Hey', attributes: {}})
>>> from vdom.helpers import h1
>>> h1('Hey')
"""
# This class should only have these 4 attributes
__slots__ = ['tag_name', 'attributes', 'children', 'key', '_frozen']
def __init__(self, tag_name, attributes=None, children=None, key=None, schema=None):
if isinstance(tag_name, dict) or isinstance(tag_name, list):
# Backwards compatible interface
warnings.warn('Passing dict to VDOM constructor is deprecated')
value = tag_name
vdom_obj = VDOM.from_dict(value)
tag_name = vdom_obj.tag_name
attributes = vdom_obj.attributes
children = vdom_obj.children
key = vdom_obj.key
self.tag_name = tag_name
self.attributes = FrozenDict(attributes) if attributes else FrozenDict()
self.children = tuple(children) if children else tuple()
self.key = key
# Validate that all children are VDOMs or strings
if not all([isinstance(c, (VDOM, string_types[:])) for c in self.children]):
raise ValueError('Children must be a list of VDOM objects or strings')
# mark completion of object creation. Object is immutable from now.
self._frozen = True
if schema is not None:
self.validate(schema)
def __setattr__(self, attr, value):
"""
Make instances immutable after creation
"""
if hasattr(self, '_frozen') and self._frozen:
raise AttributeError("Cannot change attribute of immutable object")
super(VDOM, self).__setattr__(attr, value)
def validate(self, schema):
"""
Validate VDOM against given JSON Schema
Raises ValidationError if schema does not match
"""
try:
validate(instance=self.to_dict(), schema=schema, cls=Draft4Validator)
except ValidationError as e:
raise ValidationError(_validate_err_template.format(VDOM_SCHEMA, e))
def to_dict(self):
vdom_dict = {
'tagName': self.tag_name,
'attributes': self.attributes
}
if self.key:
vdom_dict['key'] = self.key
vdom_dict['children'] = [c.to_dict() if isinstance(c, VDOM) else c for c in self.children]
return vdom_dict
def to_json(self):
return json.dumps(self.to_dict())
def to_html(self):
return self._repr_html_()
def json_contents(self):
warnings.warn('VDOM.json_contents method is deprecated, use to_json instead')
return self.to_json()
def _repr_html_(self):
"""
Return HTML representation of VDOM object.
HTML escaping is performed wherever necessary.
"""
# Use StringIO to avoid a large number of memory allocations with string concat
with io.StringIO() as out:
out.write('<{tag}'.format(tag=escape(self.tag_name)))
for k, v in self.attributes.items():
# Important values are in double quotes - cgi.escape only escapes double quotes, not single quotes!
out.write(' {key}="{value}"'.format(key=escape(k), value=escape(v)))
out.write('>')
for c in self.children:
if isinstance(c, string_types):
out.write(escape(safe_unicode(c)))
else:
out.write(c._repr_html_())
out.write('</{tag}>'.format(tag=escape(self.tag_name)))
return out.getvalue()
def _repr_mimebundle_(self, include, exclude, **kwargs):
return {
'application/vdom.v1+json': self.to_dict(),
'text/plain': self.to_html()
}
@classmethod
def from_dict(cls, value):
try:
validate(instance=value, schema=VDOM_SCHEMA, cls=Draft4Validator)
except ValidationError as e:
raise ValidationError(_validate_err_template.format(VDOM_SCHEMA, e))
return cls(
tag_name=value['tagName'],
attributes=value.get('attributes', {}),
children=[VDOM.from_dict(c) if isinstance(c, dict) else c for c in value.get('children', [])],
key=value.get('key')
)