def namespaces_of(name):
if name is None:
raise ValueError('name')
if not isinstance(name, basestring):
raise TypeError('name')
if not name:
return [SEP]
splits = [x for x in name.split(SEP) if x]
return ['/'] + ['/'+SEP.join(splits[:i]) for i in xrange(1, len(splits))]
def search_param(self, ns, key):
"""
Search for matching parameter key for search param
key. Search for key starts at ns and proceeds upwards to
the root. As such, search_param should only be called with a
relative parameter name.
search_param's behavior is to search for the first partial match.
For example, imagine that there are two 'robot_description' parameters:
- /robot_description
- /robot_description/arm
- /robot_description/base
- /pr2/robot_description
- /pr2/robot_description/base
If I start in the namespace /pr2/foo and search for
'robot_description', search_param will match
/pr2/robot_description. If I search for 'robot_description/arm'
it will return /pr2/robot_description/arm, even though that
parameter does not exist (yet).
@param ns: namespace to begin search from.
@type ns: str
@param key: Parameter key.
@type key: str
@return: key of matching parameter or None if no matching
parameter.
@rtype: str
"""
if not key or is_private(key):
raise ValueError("invalid key")
if not is_global(ns):
raise ValueError("namespace must be global")
if is_global(key):
if self.has_param(key):
return key
else:
return None
# there are more efficient implementations, but our hiearchy
# is not very deep and this is fairly clean code to read.
# - we only search for the first namespace in the key to check for a match
key_namespaces = [x for x in key.split(SEP) if x]
key_ns = key_namespaces[0]
# - corner case: have to test initial namespace first as
# negative indices won't work with 0
search_key = ns_join(ns, key_ns)
if self.has_param(search_key):
# resolve to full key
return ns_join(ns, key)
namespaces = [x for x in ns.split(SEP) if x]
for i in xrange(1, len(namespaces)+1):
search_key = SEP + SEP.join(namespaces[0:-i] + [key_ns])
if self.has_param(search_key):
# we have a match on the namespace of the key, so
# compose the full key and return it
full_key = SEP + SEP.join(namespaces[0:-i] + [key])
return full_key
return None
