Source Code for Module lxml.html.formfill

  1  from lxml.etree import XPath, ElementBase 
  2  from lxml.html import fromstring, XHTML_NAMESPACE 
  3  from lxml.html import _forms_xpath, _options_xpath, _nons, _transform_result 
  4  from lxml.html import defs 
  5  import copy 
  6   
  7  try: 
  8      basestring 
  9  except NameError: 
 10      # Python 3 
 11      basestring = str 
 12   
 13  __all__ = ['FormNotFound', 'fill_form', 'fill_form_html', 
 14             'insert_errors', 'insert_errors_html', 
 15             'DefaultErrorCreator'] 
 16   
 17 -class FormNotFound(LookupError): 
 18      """ 
 19      Raised when no form can be found 
 20      """ 
 21   
 22  _form_name_xpath = XPath('descendant-or-self::form[name=$name]|descendant-or-self::x:form[name=$name]', namespaces={'x':XHTML_NAMESPACE}) 
 23  _input_xpath = XPath('|'.join(['descendant-or-self::'+_tag for _tag in ('input','select','textarea','x:input','x:select','x:textarea')]), 
 24                                 namespaces={'x':XHTML_NAMESPACE}) 
 25  _label_for_xpath = XPath('//label[@for=$for_id]|//x:label[@for=$for_id]', 
 26                                 namespaces={'x':XHTML_NAMESPACE}) 
 27  _name_xpath = XPath('descendant-or-self::*[@name=$name]') 
 28   
 29 -def fill_form( 
 30      el, 
 31      values, 
 32      form_id=None, 
 33      form_index=None, 
 34      ): 
 35      el = _find_form(el, form_id=form_id, form_index=form_index) 
 36      _fill_form(el, values) 
 37   
 38 -def fill_form_html(html, values, form_id=None, form_index=None): 
 39      result_type = type(html) 
 40      if isinstance(html, basestring): 
 41          doc = fromstring(html) 
 42      else: 
 43          doc = copy.deepcopy(html) 
 44      fill_form(doc, values, form_id=form_id, form_index=form_index) 
 45      return _transform_result(result_type, doc) 
 46   
 47 -def _fill_form(el, values): 
 48      counts = {} 
 49      if hasattr(values, 'mixed'): 
 50          # For Paste request parameters 
 51          values = values.mixed() 
 52      inputs = _input_xpath(el) 
 53      for input in inputs: 
 54          name = input.get('name') 
 55          if not name: 
 56              continue 
 57          if _takes_multiple(input): 
 58              value = values.get(name, []) 
 59              if not isinstance(value, (list, tuple)): 
 60                  value = [value] 
 61              _fill_multiple(input, value) 
 62          elif name not in values: 
 63              continue 
 64          else: 
 65              index = counts.get(name, 0) 
 66              counts[name] = index + 1 
 67              value = values[name] 
 68              if isinstance(value, (list, tuple)): 
 69                  try: 
 70                      value = value[index] 
 71                  except IndexError: 
 72                      continue 
 73              elif index > 0: 
 74                  continue 
 75              _fill_single(input, value) 
 76   
 77 -def _takes_multiple(input): 
 78      if _nons(input.tag) == 'select' and input.get('multiple'): 
 79          # FIXME: multiple="0"? 
 80          return True 
 81      type = input.get('type', '').lower() 
 82      if type in ('radio', 'checkbox'): 
 83          return True 
 84      return False 
 85   
 86 -def _fill_multiple(input, value): 
 87      type = input.get('type', '').lower() 
 88      if type == 'checkbox': 
 89          v = input.get('value') 
 90          if v is None: 
 91              if not value: 
 92                  result = False 
 93              else: 
 94                  result = value[0] 
 95                  if isinstance(value, basestring): 
 96                      # The only valid "on" value for an unnamed checkbox is 'on' 
 97                      result = result == 'on' 
 98              _check(input, result) 
 99          else: 
100              _check(input, v in value) 
101      elif type == 'radio': 
102          v = input.get('value') 
103          _check(input, v in value) 
104      else: 
105          assert _nons(input.tag) == 'select' 
106          for option in _options_xpath(input): 
107              v = option.get('value') 
108              if v is None: 
109                  # This seems to be the default, at least on IE 
110                  # FIXME: but I'm not sure 
111                  v = option.text_content() 
112              _select(option, v in value) 
113   
114 -def _check(el, check): 
115      if check: 
116          el.set('checked', '') 
117      else: 
118          if 'checked' in el.attrib: 
119              del el.attrib['checked'] 
120   
121 -def _select(el, select): 
122      if select: 
123          el.set('selected', '') 
124      else: 
125          if 'selected' in el.attrib: 
126              del el.attrib['selected'] 
127   
128 -def _fill_single(input, value): 
129      if _nons(input.tag) == 'textarea': 
130          input.text = value 
131      else: 
132          input.set('value', value) 
133   
134 -def _find_form(el, form_id=None, form_index=None): 
135      if form_id is None and form_index is None: 
136          forms = _forms_xpath(el) 
137          for form in forms: 
138              return form 
139          raise FormNotFound( 
140              "No forms in page") 
141      if form_id is not None: 
142          form = el.get_element_by_id(form_id) 
143          if form is not None: 
144              return form 
145          forms = _form_name_xpath(el, name=form_id) 
146          if forms: 
147              return forms[0] 
148          else: 
149              raise FormNotFound( 
150                  "No form with the name or id of %r (forms: %s)" 
151                  % (id, ', '.join(_find_form_ids(el))))                
152      if form_index is not None: 
153          forms = _forms_xpath(el) 
154          try: 
155              return forms[form_index] 
156          except IndexError: 
157              raise FormNotFound( 
158                  "There is no form with the index %r (%i forms found)" 
159                  % (form_index, len(forms))) 
160   
161 -def _find_form_ids(el): 
162      forms = _forms_xpath(el) 
163      if not forms: 
164          yield '(no forms)' 
165          return 
166      for index, form in enumerate(forms): 
167          if form.get('id'): 
168              if form.get('name'): 
169                  yield '%s or %s' % (form.get('id'), 
170                                       form.get('name')) 
171              else: 
172                  yield form.get('id') 
173          elif form.get('name'): 
174              yield form.get('name') 
175          else: 
176              yield '(unnamed form %s)' % index 
177   
178  ############################################################ 
179  ## Error filling 
180  ############################################################ 
181   
182 -class DefaultErrorCreator(object): 
183      insert_before = True 
184      block_inside = True 
185      error_container_tag = 'div' 
186      error_message_class = 'error-message' 
187      error_block_class = 'error-block' 
188      default_message = "Invalid" 
189   
190 -    def __init__(self, **kw): 
191          for name, value in kw.items(): 
192              if not hasattr(self, name): 
193                  raise TypeError( 
194                      "Unexpected keyword argument: %s" % name) 
195              setattr(self, name, value) 
196   
197 -    def __call__(self, el, is_block, message): 
198          error_el = el.makeelement(self.error_container_tag) 
199          if self.error_message_class: 
200              error_el.set('class', self.error_message_class) 
201          if is_block and self.error_block_class: 
202              error_el.set('class', error_el.get('class', '')+' '+self.error_block_class) 
203          if message is None or message == '': 
204              message = self.default_message 
205          if isinstance(message, ElementBase): 
206              error_el.append(message) 
207          else: 
208              assert isinstance(message, basestring), ( 
209                  "Bad message; should be a string or element: %r" % message) 
210              error_el.text = message or self.default_message 
211          if is_block and self.block_inside: 
212              if self.insert_before: 
213                  error_el.tail = el.text 
214                  el.text = None 
215                  el.insert(0, error_el) 
216              else: 
217                  el.append(error_el) 
218          else: 
219              parent = el.getparent() 
220              pos = parent.index(el) 
221              if self.insert_before: 
222                  parent.insert(pos, error_el) 
223              else: 
224                  error_el.tail = el.tail 
225                  el.tail = None 
226                  parent.insert(pos+1, error_el) 
227   
228  default_error_creator = DefaultErrorCreator() 
229       
230   
231 -def insert_errors( 
232      el, 
233      errors, 
234      form_id=None, 
235      form_index=None, 
236      error_class="error", 
237      error_creator=default_error_creator, 
238      ): 
239      el = _find_form(el, form_id=form_id, form_index=form_index) 
240      for name, error in errors.items(): 
241          if error is None: 
242              continue 
243          for error_el, message in _find_elements_for_name(el, name, error): 
244              assert isinstance(message, (basestring, type(None), ElementBase)), ( 
245                  "Bad message: %r" % message) 
246              _insert_error(error_el, message, error_class, error_creator) 
247   
248 -def insert_errors_html(html, values, **kw): 
249      result_type = type(html) 
250      if isinstance(html, basestring): 
251          doc = fromstring(html) 
252      else: 
253          doc = copy.deepcopy(html) 
254      insert_errors(doc, values, **kw) 
255      return _transform_result(result_type, doc) 
256   
257 -def _insert_error(el, error, error_class, error_creator): 
258      if _nons(el.tag) in defs.empty_tags or _nons(el.tag) == 'textarea': 
259          is_block = False 
260      else: 
261          is_block = True 
262      if _nons(el.tag) != 'form' and error_class: 
263          _add_class(el, error_class) 
264      if el.get('id'): 
265          labels = _label_for_xpath(el, for_id=el.get('id')) 
266          if labels: 
267              for label in labels: 
268                  _add_class(label, error_class) 
269      error_creator(el, is_block, error) 
270   
271 -def _add_class(el, class_name): 
272      if el.get('class'): 
273          el.set('class', el.get('class')+' '+class_name) 
274      else: 
275          el.set('class', class_name) 
276   
277 -def _find_elements_for_name(form, name, error): 
278      if name is None: 
279          # An error for the entire form 
280          yield form, error 
281          return 
282      if name.startswith('#'): 
283          # By id 
284          el = form.get_element_by_id(name[1:]) 
285          if el is not None: 
286              yield el, error 
287          return 
288      els = _name_xpath(form, name=name) 
289      if not els: 
290          # FIXME: should this raise an exception? 
291          return 
292      if not isinstance(error, (list, tuple)): 
293          yield els[0], error 
294          return 
295      # FIXME: if error is longer than els, should it raise an error? 
296      for el, err in zip(els, error): 
297          if err is None: 
298              continue 
299          yield el, err 
300