self.filters = kwargs["filters"]
del kwargs["filters"]
else:
- self.filters = Filter([])
+ self.filters = Filter()
if "fields" in kwargs:
self.fields = set(kwargs["fields"])
del kwargs["fields"]
else:
- self.fields = set([])
+ self.fields = set()
# "update table set x = 3" => params == set
if "params" in kwargs:
#else:
# raise ParameterError, "No valid constructor found for %s : args = %r" % (self.__class__.__name__, args)
- if not self.filters: self.filters = Filter([])
+ if not self.filters: self.filters = Filter()
if not self.params: self.params = {}
- if not self.fields: self.fields = set([])
+ if not self.fields: self.fields = set()
if not self.timestamp: self.timestamp = "now"
if isinstance(self.filters, list):
f = self.filters
- self.filters = Filter([])
+ self.filters = Filter()
for x in f:
pred = Predicate(x)
self.filters.add(pred)
def clear(self):
self.action = 'get'
self.object = None
- self.filters = Filter([])
+ self.filters = Filter()
self.params = {}
- self.fields = set([])
+ self.fields = set()
self.timestamp = "now"
self.timestamp = 'now' # ignored for now
+
+ def to_sql(self, platform='', multiline=False):
+ get_params_str = lambda : ', '.join(['%s = %r' % (k, v) for k, v in self.get_params().items()])
+ get_select_str = lambda : ', '.join(self.get_select())
+
+ table = self.get_from()
+ select = 'SELECT %s' % (get_select_str() if self.get_select() else '*')
+ where = 'WHERE %s' % self.get_where() if self.get_where() else ''
+ at = 'AT %s ' % self.get_timestamp() if self.get_timestamp() else ''
+ params = 'SET %s' % get_params_str() if self.get_params() else ''
+
+ sep = ' ' if not multiline else '\n '
+ if platform: platform = "%s:" % platform
+ strmap = {
+ 'get' : '%(select)s%(sep)s%(at)sFROM %(platform)s%(table)s%(sep)s%(where)s%(sep)s',
+ 'update': 'UPDATE %(platform)s%(table)s%(sep)s%(params)s%(sep)s%(where)s%(sep)s%(select)s',
+ 'create': 'INSERT INTO %(platform)s%(table)s%(sep)s%(params)s%(sep)s%(select)s',
+ 'delete': 'DELETE FROM %(platform)s%(table)s%(sep)s%(where)s'
+ }
+
+ return strmap[self.action] % locals()
+
@returns(StringTypes)
def __str__(self):
- return "SELECT %(select)s%(from)s%(where)s%(at)s" % {
- "select": ", ".join(self.get_select()) if self.get_select() else "*",
- "from" : "\n FROM %s" % self.get_from(),
- "where" : "\n WHERE %s" % self.get_where() if self.get_where() else "",
- "at" : "\n AT %s" % self.get_timestamp() if self.get_timestamp() else ""
- }
+ return self.to_sql(multiline=True)
@returns(StringTypes)
def __repr__(self):
- return "SELECT %s FROM %s WHERE %s" % (
- ", ".join(self.get_select()) if self.get_select() else '*',
- self.get_from(),
- self.get_where()
- )
+ return self.to_sql()
def __key(self):
return (self.action, self.object, self.filters, frozendict(self.params), frozenset(self.fields))
#---------------------------------------------------------------------------
@classmethod
+ #@returns(Query)
def action(self, action, object):
+ """
+ (Internal usage). Craft a Query according to an action name
+ See methods: get, update, delete, execute.
+ Args:
+ action: A String among {"get", "update", "delete", "execute"}
+ object: The name of the queried object (String)
+ Returns:
+ The corresponding Query instance
+ """
query = Query()
query.action = action
query.object = object
return query
@classmethod
- def get(self, object): return self.action('get', object)
+ #@returns(Query)
+ def get(self, object):
+ """
+ Craft the Query which fetches the records related to a given object
+ Args:
+ object: The name of the queried object (String)
+ Returns:
+ The corresponding Query instance
+ """
+ return self.action("get", object)
@classmethod
- def update(self, object): return self.action('update', object)
+ #@returns(Query)
+ def update(self, object):
+ """
+ Craft the Query which updates the records related to a given object
+ Args:
+ object: The name of the queried object (String)
+ Returns:
+ The corresponding Query instance
+ """
+ return self.action("update", object)
@classmethod
- def create(self, object): return self.action('create', object)
+ #@returns(Query)
+ def create(self, object):
+ """
+ Craft the Query which create the records related to a given object
+ Args:
+ object: The name of the queried object (String)
+ Returns:
+ The corresponding Query instance
+ """
+ return self.action("create", object)
@classmethod
- def delete(self, object): return self.action('delete', object)
+ #@returns(Query)
+ def delete(self, object):
+ """
+ Craft the Query which delete the records related to a given object
+ Args:
+ object: The name of the queried object (String)
+ Returns:
+ The corresponding Query instance
+ """
+ return self.action("delete", object)
@classmethod
- def execute(self, object): return self.action('execute', object)
-
+ #@returns(Query)
+ def execute(self, object):
+ """
+ Craft the Query which execute a processing related to a given object
+ Args:
+ object: The name of the queried object (String)
+ Returns:
+ The corresponding Query instance
+ """
+ return self.action("execute", object)
+
+ #@returns(Query)
def at(self, timestamp):
+ """
+ Set the timestamp carried by the query
+ Args:
+ timestamp: The timestamp (it may be a python timestamp, a string
+ respecting the "%Y-%m-%d %H:%M:%S" python format, or "now")
+ Returns:
+ The self Query instance
+ """
self.timestamp = timestamp
return self
def filter_by(self, *args):
if len(args) == 1:
filters = args[0]
+ if filters == None:
+ self.filters = Filter()
+ return self
if not isinstance(filters, (set, list, tuple, Filter)):
filters = [filters]
for predicate in filters:
raise Exception, 'Invalid expression for filter'
return self
- def select(self, fields=None):
+ def select(self, *fields):
if not fields:
# Delete all fields
self.fields = set()
return self
- if not isinstance(fields, (set, list, tuple)):
- fields = [fields]
+
+ # Accept passing iterables
+ if len(fields) == 1:
+ tmp, = fields
+ if isinstance(tmp, (list, tuple, set, frozenset)):
+ fields = tuple(tmp)
+
for field in fields:
self.fields.add(field)
return self
self.params.update(params)
return self
+ def __or__(self, query):
+ assert self.action == query.action
+ assert self.object == query.object
+ assert self.timestamp == query.timestamp # XXX
+ filter = self.filters | query.filters
+ # fast dict union
+ # http://my.safaribooksonline.com/book/programming/python/0596007973/python-shortcuts/pythoncook2-chp-4-sect-17
+ params = dict(self.params, **query.params)
+ fields = self.fields | query.fields
+ return Query.action(self.action, self.object).filter_by(filter).select(fields)
+
+ def __and__(self, query):
+ assert self.action == query.action
+ assert self.object == query.object
+ assert self.timestamp == query.timestamp # XXX
+ filter = self.filters & query.filters
+ # fast dict intersection
+ # http://my.safaribooksonline.com/book/programming/python/0596007973/python-shortcuts/pythoncook2-chp-4-sect-17
+ params = dict.fromkeys([x for x in self.params if x in query.params])
+ fields = self.fields & query.fields
+ return Query.action(self.action, self.object).filter_by(filter).select(fields)
+
+ def __le__(self, query):
+ return ( self == self & query ) or ( query == self | query )
+
class AnalyzedQuery(Query):
# XXX we might need to propagate special parameters sur as DEBUG, etc.
if not method in self._subqueries:
analyzed_query = AnalyzedQuery(metadata=self.metadata)
analyzed_query.action = self.action
- if self.metadata:
- try:
- type = self.metadata.get_field_type(self.object, method)
- except ValueError ,e: # backwards 1..N
- type = method
- else:
+ try:
+ type = self.metadata.get_field_type(self.object, method)
+ except ValueError ,e: # backwards 1..N
type = method
analyzed_query.object = type
self._subqueries[method] = analyzed_query
def get_subquery_names(self):
return set(self._subqueries.keys())
+ def get_subqueries(self):
+ return self._subqueries
+
def subqueries(self):
for method, subquery in self._subqueries.iteritems():
yield (method, subquery)
def filter_by(self, filters):
- if not filters: return self
if not isinstance(filters, (set, list, tuple, Filter)):
filters = [filters]
for predicate in filters:
- if '.' in predicate.key:
- method, subkey = pred.key.split('.', 1)
+ if predicate and '.' in predicate.key:
+ method, subkey = predicate.key.split('.', 1)
# Method contains the name of the subquery, we need the type
# XXX type = self.metadata.get_field_type(self.object, method)
- sub_pred = Predicate(subkey, pred.op, pred.value)
+ sub_pred = Predicate(subkey, predicate.op, predicate.value)
self.subquery(method).filter_by(sub_pred)
else:
super(AnalyzedQuery, self).filter_by(predicate)
return self
- def select(self, fields):
- if not isinstance(fields, (set, list, tuple)):
- fields = [fields]
+ def select(self, *fields):
+
+ # XXX passing None should reset fields in all subqueries
+
+ # Accept passing iterables
+ if len(fields) == 1:
+ tmp, = fields
+ if isinstance(tmp, (list, tuple, set, frozenset)):
+ fields = tuple(tmp)
+
for field in fields:
- if '.' in field:
+ if field and '.' in field:
method, subfield = field.split('.', 1)
# Method contains the name of the subquery, we need the type
# XXX type = self.metadata.get_field_type(self.object, method)
git://git.onelab.eu / myslice.git / blobdiff