"""

Parser for HTML forms, that fills in defaults and errors. See ``render``.

"""

import re

from formencode.rewritingparser import RewritingParser, html_quote

__all__ = ['render', 'htmlliteral', 'default_formatter',

'none_formatter', 'escape_formatter',

'FillingParser']

def render(form, defaults=None, errors=None, use_all_keys=False,

error_formatters=None, add_attributes=None,

auto_insert_errors=True, auto_error_formatter=None,

text_as_default=False, checkbox_checked_if_present=False,

listener=None, encoding=None,

error_class='error', prefix_error=True,

force_defaults=True, skip_passwords=False,

data_formencode_form=None, data_formencode_ignore=None,

):

"""

Render the ``form`` (which should be a string) given the ``defaults``

and ``errors``. Defaults are the values that go in the input fields

(overwriting any values that are there) and errors are displayed

inline in the form (and also effect input classes). Returns the

rendered string.

If ``auto_insert_errors`` is true (the default) then any errors

for which ``<form:error>`` tags can't be found will be put just

above the associated input field, or at the top of the form if no

field can be found.

If ``use_all_keys`` is true, if there are any extra fields from

defaults or errors that couldn't be used in the form it will be an

error.

``error_formatters`` is a dictionary of formatter names to

one-argument functions that format an error into HTML. Some

default formatters are provided if you don't provide this.

``error_class`` is the class added to input fields when there is

an error for that field.

``add_attributes`` is a dictionary of field names to a dictionary

of attribute name/values. If the name starts with ``+`` then the

value will be appended to any existing attribute (e.g.,

``{'+class': ' important'}``).

``auto_error_formatter`` is used to create the HTML that goes

above the fields. By default it wraps the error message in a span

and adds a ``<br>``.

If ``text_as_default`` is true (default false) then ``<input

type="unknown">`` will be treated as text inputs.

If ``checkbox_checked_if_present`` is true (default false) then

``<input type="checkbox">`` will be set to ``checked`` if any

corresponding key is found in the ``defaults`` dictionary, even

a value that evaluates to False (like an empty string). This

can be used to support pre-filling of checkboxes that do not have

a ``value`` attribute, since browsers typically will only send

the name of the checkbox in the form submission if the checkbox

is checked, so simply the presence of the key would mean the box

should be checked.

``listener`` can be an object that watches fields pass; the only

one currently is in ``htmlfill_schemabuilder.SchemaBuilder``

``encoding`` specifies an encoding to assume when mixing bytes and

str text in the template.

``prefix_error`` specifies if the HTML created by auto_error_formatter is

put before the input control (default) or after the control.

``force_defaults`` specifies if a field default is not given in

the ``defaults`` dictionary then the control associated with the

field should be set as an unsuccessful control. So checkboxes will

be cleared, radio and select controls will have no value selected,

and textareas will be emptied. This defaults to ``True``, which is

appropriate the defaults are the result of a form submission.

``skip_passwords`` specifies if password fields should be skipped when

rendering form-content. If disabled the password fields will not be filled

with anything, which is useful when you don't want to return a user's

password in plain-text source.

``data_formencode_form`` if a string is passed in (default `None`) only

fields with the html attribute `data-formencode-form` that matches this

string will be processed. For example: if a HTML fragment has two forms they

can be differentiated to Formencode by decorating the input elements with

attributes such as `data-formencode-form="a"` or `data-formencode-form="b"`,

then instructing `render()` to only process the "a" or "b" fields.

``data_formencode_ignore`` if True (default `None`) fields with the html

attribute `data-formencode-ignore` will not be processed. This attribute

need only be present in the tag: `data-formencode-ignore="1"`,

`data-formencode-ignore=""` and `data-formencode-ignore` without a value are

all valid signifiers.

"""

if defaults is None:

defaults = {}

if auto_insert_errors and auto_error_formatter is None:

auto_error_formatter = default_formatter

p = FillingParser(

defaults=defaults, errors=errors,

use_all_keys=use_all_keys,

error_formatters=error_formatters,

add_attributes=add_attributes,

auto_error_formatter=auto_error_formatter,

text_as_default=text_as_default,

checkbox_checked_if_present=checkbox_checked_if_present,

listener=listener, encoding=encoding,

prefix_error=prefix_error,

error_class=error_class,

force_defaults=force_defaults,

skip_passwords=skip_passwords,

data_formencode_form=data_formencode_form,

data_formencode_ignore=data_formencode_ignore,

)

p.feed(form)

p.close()

return p.text()

class htmlliteral:

def __init__(self, html, text=None):

if text is None:

text = re.sub(r'<.*?>', '', html)

text = html.replace('&gt;', '>')

text = html.replace('&lt;', '<')

text = html.replace('&quot;', '"')

# @@: Not very complete

self.html = html

self.text = text

def __str__(self):

return self.text

def __repr__(self):

return '<%s html=%r text=%r>' % (

self.__class__.__name__, self.html, self.text)

def __html__(self):

return self.html

def default_formatter(error):

"""

Formatter that escapes the error, wraps the error in a span with

class ``error-message``, and adds a ``<br>``

"""

return '<span class="error-message">%s</span><br />\n' % html_quote(error)

def none_formatter(error):

"""

Formatter that does nothing, no escaping HTML, nothin'

"""

return error

def escape_formatter(error):

"""

Formatter that escapes HTML, no more.

"""

return html_quote(error)

def escapenl_formatter(error):

"""

Formatter that escapes HTML, and translates newlines to ``<br>``

"""

error = html_quote(error)

error = error.replace('\n', '<br>\n')

return error

def ignore_formatter(error):

"""

Formatter that emits nothing, regardless of the error.

"""

return ''

class FillingParser(RewritingParser):

r"""

Fills HTML with default values, as in a form.

Examples::

>>> defaults = dict(name='Bob Jones',

... occupation='Crazy Cultist',

... address='14 W. Canal\nNew Guinea',

... living='no',

... nice_guy=0)

>>> parser = FillingParser(defaults)

>>> parser.feed('''<input type="text" name="name" value="fill">

... <select name="occupation"> <option value="">Default</option>

... <option value="Crazy Cultist">Crazy cultist</option> </select>

... <textarea cols="20" style="width: 100%" name="address">

... An address</textarea>

... <input type="radio" name="living" value="yes">

... <input type="radio" name="living" value="no">

... <input type="checkbox" name="nice_guy" checked="checked">''')

>>> parser.close()

>>> print (parser.text()) # doctest: +NORMALIZE_WHITESPACE

<input type="text" name="name" value="Bob Jones">

<select name="occupation">

<option value="">Default</option>

<option value="Crazy Cultist" selected="selected">Crazy cultist</option>

</select>

<textarea cols="20" style="width: 100%" name="address">14 W. Canal

New Guinea</textarea>

<input type="radio" name="living" value="yes">

<input type="radio" name="living" value="no" checked="checked">

<input type="checkbox" name="nice_guy">

"""

default_encoding = 'utf8'

text_input_types = set("text hidden search tel url email datetime date"

" month week time datetime-local number range color".split())

def __init__(self, defaults, errors=None, use_all_keys=False,

error_formatters=None, error_class='error',

add_attributes=None, listener=None,

auto_error_formatter=None,

text_as_default=False, checkbox_checked_if_present=False,

encoding=None, prefix_error=True,

force_defaults=True, skip_passwords=False,

data_formencode_form=None, data_formencode_ignore=None,

):

RewritingParser.__init__(self)

self.source = None

self.lines = None

self.source_pos = None

self.defaults = defaults

self.in_textarea = None

self.skip_textarea = False

self.last_textarea_name = None

self.in_select = None

self.skip_next = False

self.errors = errors or {}

if isinstance(self.errors, str):

self.errors = {None: self.errors}

self.in_error = None

self.skip_error = False

self.use_all_keys = use_all_keys

self.used_keys = set()

self.used_errors = set()

if error_formatters is None:

self.error_formatters = default_formatter_dict

else:

self.error_formatters = error_formatters

self.error_class = error_class

self.add_attributes = add_attributes or {}

self.listener = listener

self.auto_error_formatter = auto_error_formatter

self.text_as_default = text_as_default

self.checkbox_checked_if_present = checkbox_checked_if_present

self.encoding = encoding

self.prefix_error = prefix_error

self.force_defaults = force_defaults

self.skip_passwords = skip_passwords

self.data_formencode_form = data_formencode_form

self.data_formencode_ignore = data_formencode_ignore

def str_compare(self, str1, str2):

"""

Compare the two objects as strings (coercing to strings if necessary).

Also uses encoding to compare the strings.

"""

if not isinstance(str1, str):

str1 = str(str1)

if type(str1) is type(str2):

return str1 == str2

if isinstance(str1, str):

str1 = str1.encode(self.encoding or self.default_encoding)

else:

str2 = str2.encode(self.encoding or self.default_encoding)

return str1 == str2

def close(self):

self.handle_misc(None)

RewritingParser.close(self)

unused_errors = self.errors.copy()

for key in self.used_errors:

if key in unused_errors:

del unused_errors[key]

if self.auto_error_formatter:

for key, value in unused_errors.items():

error_message = self.auto_error_formatter(value)

error_message = '<!-- for: %s -->\n%s' % (key, error_message)

self.insert_at_marker(

key, error_message)

unused_errors = {}

if self.use_all_keys:

unused = self.defaults.copy()

for key in self.used_keys:

if key in unused:

del unused[key]

assert not unused, (

"These keys from defaults were not used in the form: %s"

% ', '.join(unused))

if unused_errors:

error_text = ['%s: %s' % (key, self.errors[key])

for key in sorted(unused_errors)]

assert False, (

"These errors were not used in the form: %s"

% ', '.join(error_text))

if self.encoding is not None:

new_content = []

for item in self._content:

new_content.append(item)

self._content = new_content

self._text = self._get_text()

def skip_output(self):

return (self.in_textarea and self.skip_textarea) or self.skip_error

def add_key(self, key):

self.used_keys.add(key)

def handle_starttag(self, tag, attrs, startend=False):

self.write_pos()

if self.data_formencode_form:

for a in attrs:

if a[0] == 'data-formencode-form':

if a[1] != self.data_formencode_form:

return

if self.data_formencode_ignore:

for a in attrs:

if a[0] == 'data-formencode-ignore':

return

if tag == 'input':

self.handle_input(attrs, startend)

elif tag == 'textarea':

self.handle_textarea(attrs)

elif tag == 'select':

self.handle_select(attrs)

elif tag == 'option':

self.handle_option(attrs)

return

elif tag == 'form:error':

self.handle_error(attrs)

return

elif tag == 'form:iferror':

self.handle_iferror(attrs)

return

else:

return

if self.listener:

self.listener.listen_input(self, tag, attrs)

def handle_endtag(self, tag):

self.write_pos()

if tag == 'textarea':

self.handle_end_textarea()

elif tag == 'select':

self.handle_end_select()

elif tag == 'form:error':

self.handle_end_error()

elif tag == 'form:iferror':

self.handle_end_iferror()

def handle_startendtag(self, tag, attrs):

return self.handle_starttag(tag, attrs, True)

def handle_iferror(self, attrs):

name = self.get_attr(attrs, 'name')

assert name, (

"Name attribute in <iferror> required at %i:%i" % self.getpos())

notted = name.startswith('not ')

if notted:

name = name.split(None, 1)[1]

self.in_error = name

ok = self.errors.get(name)

if notted:

ok = not ok

if not ok:

self.skip_error = True

self.skip_next = True

def handle_end_iferror(self):

self.in_error = None

self.skip_error = False

self.skip_next = True

def handle_error(self, attrs):

name = self.get_attr(attrs, 'name')

if name is None:

name = self.in_error

assert name is not None, (

"Name attribute in <form:error> required"

" if not contained in <form:iferror> at %i:%i" % self.getpos())

formatter = self.get_attr(attrs, 'format') or 'default'

error = self.errors.get(name, '')

if error:

error = self.error_formatters[formatter](error)

self.write_text(error)

self.skip_next = True

self.used_errors.add(name)

def handle_end_error(self):

self.skip_next = True

def handle_input(self, attrs, startend):

t = (self.get_attr(attrs, 'type') or 'text').lower()

name = self.get_attr(attrs, 'name')

if self.prefix_error:

self.write_marker(name)

value = self.defaults.get(name)

if name in self.add_attributes:

for attr_name, attr_value in self.add_attributes[name].items():

if attr_name.startswith('+'):

attr_name = attr_name[1:]

self.set_attr(attrs, attr_name,

self.get_attr(attrs, attr_name, '') + attr_value)

else:

self.set_attr(attrs, attr_name, attr_value)

if (self.error_class

and self.errors.get(self.get_attr(attrs, 'name'))):

self.add_class(attrs, self.error_class)

if t in self.text_input_types:

if value is None and not self.force_defaults:

value = self.get_attr(attrs, 'value', '')

self.set_attr(attrs, 'value', value)

self.write_tag('input', attrs, startend)

self.skip_next = True

self.add_key(name)

elif t == 'checkbox':

if self.force_defaults:

selected = False

else:

selected = self.get_attr(attrs, 'checked')

if not self.get_attr(attrs, 'value'):

if self.checkbox_checked_if_present:

selected = name in self.defaults

else:

selected = value

elif self.selected_multiple(value,

self.get_attr(attrs, 'value', '')):

selected = True

if selected:

self.set_attr(attrs, 'checked', 'checked')

else:

self.del_attr(attrs, 'checked')

self.write_tag('input', attrs, startend)

self.skip_next = True

self.add_key(name)

elif t == 'radio':

if self.str_compare(value, self.get_attr(attrs, 'value', '')):

self.set_attr(attrs, 'checked', 'checked')

elif self.force_defaults or name in self.defaults:

self.del_attr(attrs, 'checked')

self.write_tag('input', attrs, startend)

self.skip_next = True

self.add_key(name)

elif t == 'password':

if self.skip_passwords:

return

if value is None and not self.force_defaults:

value = value or self.get_attr(attrs, 'value', '')

self.set_attr(attrs, 'value', value)

self.write_tag('input', attrs, startend)

self.skip_next = True

self.add_key(name)

elif t in ('file', 'image'):

self.write_tag('input', attrs, startend)

self.skip_next = True

self.add_key(name)

elif t in ('submit', 'reset', 'button'):

self.set_attr(attrs, 'value', value or

self.get_attr(attrs, 'value', ''))

self.write_tag('input', attrs, startend)

self.skip_next = True

self.add_key(name)

elif self.text_as_default:

if value is None:

value = self.get_attr(attrs, 'value', '')

self.set_attr(attrs, 'value', value)

self.write_tag('input', attrs, startend)

self.skip_next = True

self.add_key(name)

else:

assert False, ("I don't know about this kind of <input>:"

" %s at %i:%i" % ((t,) + self.getpos()))

if not self.prefix_error:

self.write_marker(name)

def handle_textarea(self, attrs):

name = self.get_attr(attrs, 'name')

if self.prefix_error:

self.write_marker(name)

if (self.error_class

and self.errors.get(name)):

self.add_class(attrs, self.error_class)

value = self.defaults.get(name, '')

if value or self.force_defaults:

self.write_tag('textarea', attrs)

self.write_text(html_quote(value))

self.write_text('</textarea>')

self.skip_textarea = True

self.in_textarea = True

self.last_textarea_name = name

self.add_key(name)

def handle_end_textarea(self):

if self.skip_textarea:

self.skip_textarea = False

else:

self.write_text('</textarea>')

self.in_textarea = False

self.skip_next = True

if not self.prefix_error:

self.write_marker(self.last_textarea_name)

self.last_textarea_name = None

def handle_select(self, attrs):

name = self.get_attr(attrs, 'name', False)

if name and self.prefix_error:

self.write_marker(name)

if (self.error_class

and self.errors.get(name)):

self.add_class(attrs, self.error_class)

self.in_select = self.get_attr(attrs, 'name', False)

self.write_tag('select', attrs)

self.skip_next = True

self.add_key(self.in_select)

def handle_end_select(self):

self.write_text('</select>')

self.skip_next = True

if not self.prefix_error and self.in_select:

self.write_marker(self.in_select)

self.in_select = None

def handle_option(self, attrs):

assert self.in_select is not None, (

"<option> outside of <select> at %i:%i" % self.getpos())

if self.in_select is not False:

if self.force_defaults or self.in_select in self.defaults:

if self.selected_multiple(self.defaults.get(self.in_select),

self.get_attr(attrs, 'value', '')):

self.set_attr(attrs, 'selected', 'selected')

self.add_key(self.in_select)

else:

self.del_attr(attrs, 'selected')

self.write_tag('option', attrs)

self.skip_next = True

def selected_multiple(self, obj, value):

"""

Returns true/false if obj indicates that value should be

selected. If obj has a __contains__ method it is used, otherwise

identity is used.

"""

if obj is None:

return False

if isinstance(obj, str):

return obj == value

if hasattr(obj, '__contains__'):

if value in obj:

return True

if hasattr(obj, '__iter__'):

for inner in obj:

if self.str_compare(inner, value):

return True

return self.str_compare(obj, value)

def write_marker(self, marker):

self._content.append((marker,))

def insert_at_marker(self, marker, text):

for i, item in enumerate(self._content):

if item == (marker,):

self._content.insert(i, text)

break

else:

self._content.insert(0, text)

# This can potentially be extended globally

default_formatter_dict = dict(

default=default_formatter,

none=none_formatter,

escape=escape_formatter,

escapenl=escapenl_formatter,

ignore=ignore_formatter)