camera/docs/metadata_validate.py - platform/system/media - Git at Google

 #!/usr/bin/python

 #
 # Copyright (C) 2012 The Android Open Source Project
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
 # You may obtain a copy of the License at
 #
 #      http://www.apache.org/licenses/LICENSE-2.0
 #
 # Unless required by applicable law or agreed to in writing, software
 # distributed under the License is distributed on an "AS IS" BASIS,
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
 #

 """
 Usage:
   metadata_validate.py <filename.xml>
   - validates that the metadata properties defined in filename.xml are
     semantically correct.
   - does not do any XSD validation, use xmllint for that (in metadata-validate)

 Module:
   A set of helpful functions for dealing with BeautifulSoup element trees.
   Especially the find_* and fully_qualified_name functions.

 Dependencies:
   BeautifulSoup - an HTML/XML parser available to download from
                   http://www.crummy.com/software/BeautifulSoup/
 """

 from bs4 import BeautifulSoup
 from bs4 import Tag
 import sys


 #####################
 #####################

 def fully_qualified_name(entry):
   """
   Calculates the fully qualified name for an entry by walking the path
   to the root node.

   Args:
     entry: a BeautifulSoup Tag corresponding to an <entry ...> XML node

   Returns:
     A string with the full name, e.g. "android.lens.info.availableApertureSizes"
   """
   filter_tags = ['namespace', 'section']
   parents = [i['name'] for i in entry.parents if i.name in filter_tags]

   name = entry['name']

   parents.reverse()
   parents.append(name)

   fqn = ".".join(parents)

   return fqn

 def find_parent_by_name(element, names):
   """
   Find the ancestor for an element whose name matches one of those
   in names.

   Args:
     element: A BeautifulSoup Tag corresponding to an XML node

   Returns:
     A BeautifulSoup element corresponding to the matched parent, or None.

     For example, assuming the following XML structure:
       <static>
         <anything>
           <entry name="Hello" />   # this is in variable 'Hello'
         </anything>
       </static>

       el = find_parent_by_name(Hello, ['static'])
       # el is now a value pointing to the '<static>' element
   """
   matching_parents = [i.name for i in element.parents if i.name in names]

   if matching_parents:
     return matching_parents[0]
   else:
     return None

 def find_all_child_tags(element, tag):
     """
     Finds all the children that are a Tag (as opposed to a NavigableString),
     with a name of tag. This is useful to filter out the NavigableString out
     of the children.

     Args:
       element: A BeautifulSoup Tag corresponding to an XML node
       tag: A string representing the name of the tag

     Returns:
       A list of Tag instances

       For example, given the following XML structure:
         <enum>                    # This is the variable el
           Hello world             # NavigableString
           <value>Apple</value>    # this is the variale apple (Tag)
           <value>Orange</value>   # this is the variable orange (Tag)
           Hello world again       # NavigableString
         </enum>

         lst = find_all_child_tags(el, 'value')
         # lst is [apple, orange]

     """
     matching_tags = [i for i in element.children if isinstance(i, Tag) and i.name == tag]
     return matching_tags

 def find_child_tag(element, tag):
     """
     Finds the first child that is a Tag with the matching name.

     Args:
       element: a BeautifulSoup Tag
       tag: A String representing the name of the tag

     Returns:
       An instance of a Tag, or None if there was no matches.

       For example, given the following XML structure:
         <enum>                    # This is the variable el
           Hello world             # NavigableString
           <value>Apple</value>    # this is the variale apple (Tag)
           <value>Orange</value>   # this is the variable orange (Tag)
           Hello world again       # NavigableString
         </enum>

         res = find_child_tag(el, 'value')
         # res is apple
     """
     matching_tags = find_all_child_tags(element, tag)
     if matching_tags:
         return matching_tags[0]
     else:
         return None

 def find_kind(element):
   """
   Finds the kind Tag ancestor for an element.

   Args:
     element: a BeautifulSoup Tag

   Returns:
     a BeautifulSoup tag, or None if there was no matches

   Remarks:
     This function only makes sense to be called for an Entry, Clone, or
     InnerNamespace XML types. It will always return 'None' for other nodes.
   """
   kinds = ['dynamic', 'static', 'controls']
   parent_kind = find_parent_by_name(element, kinds)
   return parent_kind

 def validate_error(msg):
   """
   Print a validation error to stderr.

   Args:
     msg: a string you want to be printed
   """
   print >> sys.stderr, "Validation error: " + msg


 def validate_clones(soup):
   """
   Validate that all <clone> elements point to an existing <entry> element.

   Args:
     soup - an instance of BeautifulSoup

   Returns:
     True if the validation succeeds, False otherwise
   """
   success = True

   for clone in soup.find_all("clone"):
     clone_entry = clone['entry']
     clone_kind = clone['kind']

     parent_kind = find_kind(clone)

     find_entry = lambda x: x.name == 'entry'                           \
                        and find_kind(x) == clone_kind                  \
                        and fully_qualified_name(x) == clone_entry
     matching_entry = soup.find(find_entry)

     if matching_entry is None:
       error_msg = ("Did not find corresponding clone entry '%s' " +    \
                "with kind '%s'") %(clone_entry, clone_kind)
       validate_error(error_msg)
       success = False

   return success

 # All <entry> elements with container=$foo have a <$foo> child
 # If type="enum", <enum> tag is present
 # In <enum> for all <value id="$x">, $x is numeric
 def validate_entries(soup):
   """
   Validate all <entry> elements with the following rules:
     * If there is a container="$foo" attribute, there is a <$foo> child
     * If there is a type="enum" attribute, there is an <enum> child
     * In the <enum> child, all <value id="$x"> have a numeric $x

   Args:
     soup - an instance of BeautifulSoup

   Returns:
     True if the validation succeeds, False otherwise
   """
   success = True
   for entry in soup.find_all("entry"):
     entry_container = entry.attrs.get('container')

     if entry_container is not None:
       container_tag = entry.find(entry_container)

       if container_tag is None:
         success = False
         validate_error(("Entry '%s' in kind '%s' has type '%s' but " +  \
                  "missing child element <%s>")                          \
                  %(fully_qualified_name(entry), find_kind(entry),       \
                  entry_container, entry_container))

     typ = entry.attrs.get('type')
     if typ == 'enum':
       if entry.enum is None:
         validate_error(("Entry '%s' in kind '%s' is missing enum")     \
                                % (fully_qualified_name(entry), find_kind(entry),
                                   ))

       if typ == 'enum' and entry.enum is not None:

         for value in entry.enum.find_all('value'):
           value_id = value.attrs.get('id')

           if value_id is not None:
             try:
               id_int = int(value_id, 0) #autoguess base
             except ValueError:
               validate_error(("Entry '%s' has id '%s', which is not" + \
                                         " numeric.")                   \
                              %(fully_qualified_name(entry), value_id))
               success = False

   return success

 def validate_xml(file_name):
   """
   Validate all XML nodes according to the rules in validate_clones and
   validate_entries.

   Args:
     file_name - a string path to an XML file we wish to validate

   Returns:
     a BeautifulSoup instance if validation succeeds, None otherwise
   """

   xml = file(file_name).read()
   soup = BeautifulSoup(xml, features='xml')

   succ = validate_clones(soup)
   succ = validate_entries(soup) and succ

   if succ:
     return soup
   else:
     return None

 #####################
 #####################

 if __name__ == "__main__":
   if len(sys.argv) <= 1:
     print >> sys.stderr, "Usage: %s <filename.xml>" % (sys.argv[0])
     sys.exit(0)

   file_name = sys.argv[1]
   succ = validate_xml(file_name) is not None

   if succ:
     print "%s: SUCCESS! Document validated" %(file_name)
     sys.exit(0)
   else:
     print >> sys.stderr, "%s: ERRORS: Document failed to validate" %(file_name)
     sys.exit(1)
	#!/usr/bin/python

	#
	# Copyright (C) 2012 The Android Open Source Project
	#
	# Licensed under the Apache License, Version 2.0 (the "License");
	# you may not use this file except in compliance with the License.
	# You may obtain a copy of the License at
	#
	# http://www.apache.org/licenses/LICENSE-2.0
	#
	# Unless required by applicable law or agreed to in writing, software
	# distributed under the License is distributed on an "AS IS" BASIS,
	# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	# See the License for the specific language governing permissions and
	# limitations under the License.
	#

	"""
	Usage:
	metadata_validate.py <filename.xml>
	- validates that the metadata properties defined in filename.xml are
	semantically correct.
	- does not do any XSD validation, use xmllint for that (in metadata-validate)

	Module:
	A set of helpful functions for dealing with BeautifulSoup element trees.
	Especially the find_* and fully_qualified_name functions.

	Dependencies:
	BeautifulSoup - an HTML/XML parser available to download from
	http://www.crummy.com/software/BeautifulSoup/
	"""

	from bs4 import BeautifulSoup
	from bs4 import Tag
	import sys


	#####################
	#####################

	def fully_qualified_name(entry):
	"""
	Calculates the fully qualified name for an entry by walking the path
	to the root node.

	Args:
	entry: a BeautifulSoup Tag corresponding to an <entry ...> XML node

	Returns:
	A string with the full name, e.g. "android.lens.info.availableApertureSizes"
	"""
	filter_tags = ['namespace', 'section']
	parents = [i['name'] for i in entry.parents if i.name in filter_tags]

	name = entry['name']

	parents.reverse()
	parents.append(name)

	fqn = ".".join(parents)

	return fqn

	def find_parent_by_name(element, names):
	"""
	Find the ancestor for an element whose name matches one of those
	in names.

	Args:
	element: A BeautifulSoup Tag corresponding to an XML node

	Returns:
	A BeautifulSoup element corresponding to the matched parent, or None.

	For example, assuming the following XML structure:
	<static>
	<anything>
	<entry name="Hello" /> # this is in variable 'Hello'
	</anything>
	</static>

	el = find_parent_by_name(Hello, ['static'])
	# el is now a value pointing to the '<static>' element
	"""
	matching_parents = [i.name for i in element.parents if i.name in names]

	if matching_parents:
	return matching_parents[0]
	else:
	return None

	def find_all_child_tags(element, tag):
	"""
	Finds all the children that are a Tag (as opposed to a NavigableString),
	with a name of tag. This is useful to filter out the NavigableString out
	of the children.

	Args:
	element: A BeautifulSoup Tag corresponding to an XML node
	tag: A string representing the name of the tag

	Returns:
	A list of Tag instances

	For example, given the following XML structure:
	<enum> # This is the variable el
	Hello world # NavigableString
	<value>Apple</value> # this is the variale apple (Tag)
	<value>Orange</value> # this is the variable orange (Tag)
	Hello world again # NavigableString
	</enum>

	lst = find_all_child_tags(el, 'value')
	# lst is [apple, orange]

	"""
	matching_tags = [i for i in element.children if isinstance(i, Tag) and i.name == tag]
	return matching_tags

	def find_child_tag(element, tag):
	"""
	Finds the first child that is a Tag with the matching name.

	Args:
	element: a BeautifulSoup Tag
	tag: A String representing the name of the tag

	Returns:
	An instance of a Tag, or None if there was no matches.

	For example, given the following XML structure:
	<enum> # This is the variable el
	Hello world # NavigableString
	<value>Apple</value> # this is the variale apple (Tag)
	<value>Orange</value> # this is the variable orange (Tag)
	Hello world again # NavigableString
	</enum>

	res = find_child_tag(el, 'value')
	# res is apple
	"""
	matching_tags = find_all_child_tags(element, tag)
	if matching_tags:
	return matching_tags[0]
	else:
	return None

	def find_kind(element):
	"""
	Finds the kind Tag ancestor for an element.

	Args:
	element: a BeautifulSoup Tag

	Returns:
	a BeautifulSoup tag, or None if there was no matches

	Remarks:
	This function only makes sense to be called for an Entry, Clone, or
	InnerNamespace XML types. It will always return 'None' for other nodes.
	"""
	kinds = ['dynamic', 'static', 'controls']
	parent_kind = find_parent_by_name(element, kinds)
	return parent_kind

	def validate_error(msg):
	"""
	Print a validation error to stderr.

	Args:
	msg: a string you want to be printed
	"""
	print >> sys.stderr, "Validation error: " + msg


	def validate_clones(soup):
	"""
	Validate that all <clone> elements point to an existing <entry> element.

	Args:
	soup - an instance of BeautifulSoup

	Returns:
	True if the validation succeeds, False otherwise
	"""
	success = True

	for clone in soup.find_all("clone"):
	clone_entry = clone['entry']
	clone_kind = clone['kind']

	parent_kind = find_kind(clone)

	find_entry = lambda x: x.name == 'entry' \
	and find_kind(x) == clone_kind \
	and fully_qualified_name(x) == clone_entry
	matching_entry = soup.find(find_entry)

	if matching_entry is None:
	error_msg = ("Did not find corresponding clone entry '%s' " + \
	"with kind '%s'") %(clone_entry, clone_kind)
	validate_error(error_msg)
	success = False

	return success

	# All <entry> elements with container=$foo have a <$foo> child
	# If type="enum", <enum> tag is present
	# In <enum> for all <value id="$x">, $x is numeric
	def validate_entries(soup):
	"""
	Validate all <entry> elements with the following rules:
	* If there is a container="$foo" attribute, there is a <$foo> child
	* If there is a type="enum" attribute, there is an <enum> child
	* In the <enum> child, all <value id="$x"> have a numeric $x

	Args:
	soup - an instance of BeautifulSoup

	Returns:
	True if the validation succeeds, False otherwise
	"""
	success = True
	for entry in soup.find_all("entry"):
	entry_container = entry.attrs.get('container')

	if entry_container is not None:
	container_tag = entry.find(entry_container)

	if container_tag is None:
	success = False
	validate_error(("Entry '%s' in kind '%s' has type '%s' but " + \
	"missing child element <%s>") \
	%(fully_qualified_name(entry), find_kind(entry), \
	entry_container, entry_container))

	typ = entry.attrs.get('type')
	if typ == 'enum':
	if entry.enum is None:
	validate_error(("Entry '%s' in kind '%s' is missing enum") \
	% (fully_qualified_name(entry), find_kind(entry),
	))

	if typ == 'enum' and entry.enum is not None:

	for value in entry.enum.find_all('value'):
	value_id = value.attrs.get('id')

	if value_id is not None:
	try:
	id_int = int(value_id, 0) #autoguess base
	except ValueError:
	validate_error(("Entry '%s' has id '%s', which is not" + \
	" numeric.") \
	%(fully_qualified_name(entry), value_id))
	success = False

	return success

	def validate_xml(file_name):
	"""
	Validate all XML nodes according to the rules in validate_clones and
	validate_entries.

	Args:
	file_name - a string path to an XML file we wish to validate

	Returns:
	a BeautifulSoup instance if validation succeeds, None otherwise
	"""

	xml = file(file_name).read()
	soup = BeautifulSoup(xml, features='xml')

	succ = validate_clones(soup)
	succ = validate_entries(soup) and succ

	if succ:
	return soup
	else:
	return None

	#####################
	#####################

	if __name__ == "__main__":
	if len(sys.argv) <= 1:
	print >> sys.stderr, "Usage: %s <filename.xml>" % (sys.argv[0])
	sys.exit(0)

	file_name = sys.argv[1]
	succ = validate_xml(file_name) is not None

	if succ:
	print "%s: SUCCESS! Document validated" %(file_name)
	sys.exit(0)
	else:
	print >> sys.stderr, "%s: ERRORS: Document failed to validate" %(file_name)
	sys.exit(1)