Ticket #3094: validators.3.py

File validators.3.py, 5.4 KB (added by David Danier <goliath.mailinglist@…>, 18 years ago)
Line 
1from StringIO import StringIO
2from django.utils.translation import ugettext as _
3from lxml import etree
4import re
5
6# example XmlField:
7#class XmlField(forms.CharField):
8# widget = forms.Textarea
9#
10# def __init__(self, schema_path=None, additional_root_element=None, *args, **kwargs):
11# super(XmlField, self).__init__(*args, **kwargs)
12# self.additional_root_element = additional_root_element
13# self.schema_path = schema_path
14#
15# def clean(self, value):
16# from ....validators import RelaxNGValidator
17# super(XmlField, self).clean(value)
18# schema_path = self.schema_path
19# xml_validator = RelaxNGValidator(schema_path, self.additional_root_element)
20# return xml_validator.forms_validate(value)
21
22# copy of django.core.validators.ValidationError, cut most of the code out
23# needed to throw different exceptions for new/old-forms
24class ValidationError(Exception):
25 def __init__(self, messages): # messages must be a list
26 self.messages = messages
27
28# for rnc-files see:
29# rnc2rng: http://www.gnosis.cx/download/relax/
30class RelaxNGValidator(object):
31 "Validate against a Relax NG schema"
32 def __init__(self, schema_path, additional_root_element=None):
33 self.schema_path = schema_path
34 self.additional_root_element = additional_root_element
35
36 def raiseValidationError(self, xml_data, error_log):
37 display_errors = []
38 if self.additional_root_element:
39 adjust_line = -1
40 else:
41 adjust_line = 0
42 lines = xml_data.split('\n')
43 for error in error_log:
44 # Scrape the lxml error messages to reword them more nicely.
45 m = re.search(r'Opening and ending tag mismatch: (.+?) line (\d+?) and (.+?)$', error.message)
46 if m:
47 display_errors.append(_(u'Please close the unclosed %(tag)s tag from line %(line)s. (Line starts with "%(start)s".)') % \
48 {'tag':m.group(1).replace('/', ''), 'line':int(m.group(2)) + adjust_line, 'start':lines[int(m.group(2)) - 1][:30]})
49 continue
50 m = re.search(r'Did not expect text in element (.+?) content', error.message)
51 if m:
52 display_errors.append(_(u'Some text starting on line %(line)s is not allowed in that context. (Line starts with "%(start)s".)') % \
53 {'line':error.line + adjust_line, 'start':lines[int(error.line) - 1][:30]})
54 continue
55 m = re.search(r'Specification mandate value for attribute (.+?)$', error.message)
56 if m:
57 display_errors.append(_(u'"%(attr)s" on line %(line)s is an invalid attribute. (Line starts with "%(start)s".)') % \
58 {'attr':m.group(1), 'line':error.line + adjust_line, 'start':lines[int(error.line) - 1][:30]})
59 continue
60 m = re.search(r'Invalid attribute (.+?) for element (.+?)$', error.message)
61 if m:
62 display_errors.append(_(u'"%(attr)s" on line %(line)s is an invalid attribute. (Line starts with "%(start)s".)') % \
63 {'attr':m.group(1), 'line':error.line + adjust_line, 'start':lines[int(error.line) - 1][:30]})
64 continue
65 m = re.search(r'Did not expect element (.+?) there', error.message)
66 if m:
67 display_errors.append(_(u'"<%(tag)s>" on line %(line)s is an invalid tag. (Line starts with "%(start)s".)') % \
68 {'tag':m.group(1), 'line':error.line + adjust_line, 'start':lines[int(error.line) - 1][:30]})
69 continue
70 m = re.search(r'Element (.+?) failed to validate attributes', error.message)
71 if m:
72 display_errors.append(_(u'A tag on line %(line)s is missing one or more required attributes. (Line starts with "%(start)s".)') % \
73 {'line':error.line + adjust_line, 'start':lines[int(error.line) - 1][:30]})
74 continue
75 m = re.search(r'Invalid attribute (.+?) for element (.+?)$', error.message)
76 if m:
77 display_errors.append(_(u'The "%(attr)s" attribute on line %(line)s has an invalid value. (Line starts with "%(start)s".)') % \
78 {'attr':m.group(1), 'line':error.line + adjust_line, 'start':lines[int(error.line) - 1][:30]})
79 continue
80 # Failing all those checks, use the default error message.
81 display_errors.append(u'Line %s: %s [%s]' % (error.line + adjust_line, error.message, error.level_name))
82 raise ValidationError, display_errors
83
84 def validate(self, xml_data):
85 self.errors = []
86 if self.additional_root_element:
87 xml_data = '<%(are)s>\n%(data)s\n</%(are)s>' % {
88 'are': self.additional_root_element,
89 'data': xml_data
90 }
91
92 etree.clearErrorLog()
93 try:
94 doc = etree.parse(StringIO(xml_data))
95 except etree.XMLSyntaxError, e:
96 self.raiseValidationError(xml_data, e.error_log)
97 etree.clearErrorLog()
98
99 schema_path = self.schema_path
100 if schema_path:
101 if not schema_path[0] == '/':
102 import os.path
103 schema_path = os.path.join(os.path.dirname(__file__), "rng/%s" % schema_path)
104
105 try:
106 rng_doc = etree.parse(schema_path)
107 rng = etree.RelaxNG(rng_doc)
108 except (etree.XMLSyntaxError, etree.RelaxNGParseError), e:
109 import os.path
110 raise ValidationError, [_(u"Could not load %s for validation, please contact the admin") % os.path.basename(self.schema_path)]
111 if not rng(doc):
112 self.raiseValidationError(xml_data, rng.error_log)
113
114 # oldforms-way of using this
115 def __call__(self, field_data, all_data):
116 from django.core.validators import ValidationError as CoreValidationError
117 try:
118 self.validate(field_data)
119 except ValidationError, e:
120 raise CoreValidationError(e.messages)
121
122 # newforms-way of using this
123 def forms_validate(self, value):
124 from django.newforms.util import ValidationError as FormsValidationError
125 from django.utils.encoding import smart_unicode
126 try:
127 self.validate(value)
128 except ValidationError, e:
129 raise FormsValidationError(e.messages)
130 return smart_unicode(value)
131
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