def __init__(self, name='', array=None, maps=None, attributes=None):
self.name = quote(name)
self.array = array
self.maps = maps or odict()
self.attributes = attributes or {}
self._id = name
self._filters = []
def parse_querystring(query):
"""
Parse a query_string returning the requested variables, dimensions, and CEs.
>>> parse_querystring('a,b')
({'a': (slice(None, None, None),), 'b': (slice(None, None, None),)}, [])
>>> parse_querystring('a[0],b[1]')
({'a': (slice(0, 1, 1),), 'b': (slice(1, 2, 1),)}, [])
>>> parse_querystring('a[0],b[1]&foo.bar>1')
({'a': (slice(0, 1, 1),), 'b': (slice(1, 2, 1),)}, ['foo.bar>1'])
>>> parse_querystring('a[0],b[1]&foo.bar>1&LAYERS=SST')
({'a': (slice(0, 1, 1),), 'b': (slice(1, 2, 1),)}, ['foo.bar>1', 'LAYERS=SST'])
>>> parse_querystring('foo.bar>1&LAYERS=SST')
({}, ['foo.bar>1', 'LAYERS=SST'])
"""
if query is None: return {}, []
query = unquote(query)
constraints = query.split('&')
# Check if the first item is either a list of variables (projection)
# or a selection.
relops = ['<', '<=', '>', '>=', '=', '!=',' =~']
for relop in relops:
if relop in constraints[0]:
vars_ = []
queries = constraints[:]
break
else:
vars_ = constraints[0].split(',')
queries = constraints[1:]
fields = odict()
p = re.compile(r'(?P<name>[^[]+)(?P<shape>(\[[^\]]+\])*)')
for var in vars_:
if var:
# Check if the var has a slice.
c = p.match(var).groupdict()
id_ = quote(c['name'])
fields[id_] = getslice(c['shape'])
return fields, queries
