-# $Id$
-# $URL$
+#
+# Thierry Parmentelat - INRIA
+#
from types import StringTypes
try:
set
A type of parameter that represents a filter on one or more
columns of a database table.
Special features provide support for negation, upper and lower bounds,
- as well as sorting and clipping.
+ sorting and clipping and more...
fields should be a dictionary of field names and types.
example : filter = { 'hostname' : '*.edu' , site_id : [34,54] }
- Whether the filter represents an intersection (AND) or a union (OR)
- of these criteria is determined as follows:
- * if the dictionnary has the '-AND' or the '-OR' key, this is chosen
- * otherwise, the join_with argument, as provided to the sql method below,
- is expected to hold the 'AND' or 'OR' string
- this argument defaults to 'AND' and in most of the code, this default applies
- as the join_with argument is left unspecified
-
-
Special features:
- * a field starting with '&' or '|' should refer to a sequence type
- the semantic is then that the object value (expected to be a list)
- should contain all (&) or any (|) value specified in the corresponding
- filter value. See other examples below.
- example : filter = { '|role_ids' : [ 20, 40 ] }
- example : filter = { '|roles' : ['tech', 'pi'] }
- example : filter = { '&roles' : ['admin', 'tech'] }
- example : filter = { '&roles' : 'tech' }
-
* a field starting with the ~ character means negation.
example : filter = { '~peer_id' : None }
SQL wildcard character.
example : filter = { 'hostname' : '*.jp' }
+ * a field starting with '&' or '|' should refer to a sequence type
+ the semantics is then that the object value (expected to be a list)
+ should contain all (&) or any (|) value specified in the corresponding
+ filter value. See other examples below.
+ example : filter = { '|role_ids' : [ 20, 40 ] }
+ example : filter = { '|roles' : ['tech', 'pi'] }
+ example : filter = { '&roles' : ['admin', 'tech'] }
+ example : filter = { '&roles' : 'tech' }
+
* the filter's keys starting with '-' are special and relate to sorting and clipping
- * '-SORT' : a field name, or an ordered list of field names that are used for sorting
- these fields may start with + (default) or - for denoting increasing or decreasing order
+ * '-SORT' : a field name, or an ordered list of field names that are used for sorting
+ these fields may start with + (default) or - for denoting increasing or decreasing order
example : filter = { '-SORT' : [ '+node_id', '-hostname' ] }
- * '-OFFSET' : the number of first rows to be ommitted
- * '-LIMIT' : the amount of rows to be returned
+ * '-OFFSET' : the number of first rows to be ommitted
+ * '-LIMIT' : the amount of rows to be returned
example : filter = { '-OFFSET' : 100, '-LIMIT':25}
+ * similarly the two special keys below allow to change the semantics of multi-keys filters
+ * '-AND' : select rows that match ALL the criteria (default)
+ * '-OR' : select rows that match ANY criteria
+ The value attached to these keys is ignored.
+ Please note however that because a Filter is a dict, you cannot provide two criteria on a given key.
+
Here are a few realistic examples
value = "NULL"
elif isinstance(value, StringTypes) and \
(value.find("*") > -1 or value.find("%") > -1):
- operator = "LIKE"
+ operator = "ILIKE"
# insert *** in pattern instead of either * or %
# we dont use % as requests are likely to %-expansion later on
# actual replacement to % done in PostgreSQL.py
value = "FALSE"
clause = "%s %s %s" % (field, operator, value)
else:
- value = map(str, map(api.db.quote, value))
- do_join = True
vals = {}
for val in value:
base_op, val = get_op_and_val(val)
- if base_op != '=':
- do_join = False
if base_op in vals:
vals[base_op].append(val)
else:
vals[base_op] = [val]
- if do_join:
- if modifiers['&']:
- operator = "@>"
- value = "ARRAY[%s]" % ", ".join(value)
- elif modifiers['|']:
- operator = "&&"
- value = "ARRAY[%s]" % ", ".join(value)
- else:
- operator = "IN"
- value = "(%s)" % ", ".join(value)
- clause = "%s %s %s" % (field, operator, value)
- else:
- # We need something more complex
- subclauses = []
- for operator in vals.keys():
- if operator == '=':
- subclauses.append("(%s IN (%s))" % (field, ",".join(vals[operator])))
- elif operator == 'IS':
- subclauses.append("(%s IS NULL)" % field)
+ subclauses = []
+ for operator in vals.keys():
+ if operator == '=':
+ if modifiers['&']:
+ subclauses.append("(%s @> ARRAY[%s])" % (field, ",".join(vals[operator])))
+ elif modifiers['|']:
+ subclauses.append("(%s && ARRAY[%s])" % (field, ",".join(vals[operator])))
else:
- for value in vals[operator]:
- subclauses.append("(%s %s %s)" % (field, operator, value))
- clause = "(" + " OR ".join(subclauses) + ")"
+ subclauses.append("(%s IN (%s))" % (field, ",".join(vals[operator])))
+ elif operator == 'IS':
+ subclauses.append("(%s IS NULL)" % field)
+ else:
+ for value in vals[operator]:
+ subclauses.append("(%s %s %s)" % (field, operator, value))
+ clause = "(" + " OR ".join(subclauses) + ")"
else:
operator, value = get_op_and_val(value)
+
clause = "%s %s %s" % (field, operator, value)
if modifiers['~']: