-# $Id$
-# $URL$
+#
+# Thierry Parmentelat - INRIA
+#
from types import StringTypes
-try:
- set
-except NameError:
- from sets import Set
- set = Set
-
import time
from PLC.Faults import *
from PLC.Parameter import Parameter, Mixed, python_type
+from PLC.Logger import logger
class Filter(Parameter, dict):
"""
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.
+ Special features provide support for negation, upper and lower bounds,
+ sorting and clipping and more...
fields should be a dictionary of field names and types.
filter should be a dictionary of field names and values
- representing the criteria for filtering.
+ representing the criteria for filtering.
example : filter = { 'hostname' : '*.edu' , site_id : [34,54] }
- Whether the filter represents an intersection (AND) or a union (OR)
- of these criteria is determined by the join_with argument
- provided to the sql method below
- 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' }
+ Special features:
* a field starting with the ~ character means negation.
example : filter = { '~peer_id' : None }
example : filter = { '>time' : 1178531418 }
in this example the integer value denotes a unix timestamp
- * if a value is a sequence type, then it should represent
+ * if a value is a sequence type, then it should represent
a list of possible values for that field
example : filter = { 'node_id' : [12,34,56] }
* a (string) value containing either a * or a % character is
treated as a (sql) pattern; * are replaced with % that is the
SQL wildcard character.
- example : filter = { 'hostname' : '*.jp' }
+ 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
- GetNodes ( { 'node_type' : 'regular' , 'hostname' : '*.edu' , '-SORT' : 'hostname' , '-OFFSET' : 30 , '-LIMIT' : 25 } )
+ GetNodes ( { 'node_type' : 'regular' , 'hostname' : '*.edu' ,
+ '-SORT' : 'hostname' , '-OFFSET' : 30 , '-LIMIT' : 25 } )
would return regular (usual) nodes matching '*.edu' in alphabetical order from 31th to 55th
+ GetNodes ( { '~peer_id' : None } )
+ returns the foreign nodes - that have an integer peer_id
+
GetPersons ( { '|role_ids' : [ 20 , 40] } )
would return all persons that have either pi (20) or tech (40) roles
all 4 forms are equivalent and would return all admin users in the system
"""
+ debug=False
+# debug=True
+
def __init__(self, fields = {}, filter = {}, doc = "Attribute filter"):
# Store the filter in our dict instance
dict.__init__(self, filter)
# Declare ourselves as a type of parameter that can take
# either a value or a list of values for each of the specified
# fields.
- self.fields = dict ( [ ( field, Mixed (expected, [expected]))
+ self.fields = dict ( [ ( field, Mixed (expected, [expected]))
for (field,expected) in fields.iteritems() ] )
# Null filter means no filter
Returns a SQL conditional that represents this filter.
"""
+ if self.has_key('-AND'):
+ del self['-AND']
+ join_with='AND'
+ if self.has_key('-OR'):
+ del self['-OR']
+ join_with='OR'
+
+ self.join_with=join_with
+
# So that we always return something
if join_with == "AND":
conditionals = ["True"]
else:
assert join_with in ("AND", "OR")
- # init
+ # init
sorts = []
clips = []
for field, value in self.iteritems():
- # handle negation, numeric comparisons
- # simple, 1-depth only mechanism
+ # handle negation, numeric comparisons
+ # simple, 1-depth only mechanism
- modifiers={'~' : False,
- '<' : False, '>' : False,
- '[' : False, ']' : False,
+ modifiers={'~' : False,
+ '<' : False, '>' : False,
+ '[' : False, ']' : False,
'-' : False,
'&' : False, '|' : False,
- }
+ }
def check_modifiers(field):
if field[0] in modifiers.keys():
modifiers[field[0]] = True
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
if isinstance(value, (list, tuple, set)):
# handling filters like '~slice_id':[]
# this should return true, as it's the opposite of 'slice_id':[] which is false
- # prior to this fix, 'slice_id':[] would have returned ``slice_id IN (NULL) '' which is unknown
+ # prior to this fix, 'slice_id':[] would have returned ``slice_id IN (NULL) '' which is unknown
# so it worked by coincidence, but the negation '~slice_ids':[] would return false too
if not value:
if modifiers['&'] or modifiers['|']:
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['~']:
clip_part += " ORDER BY " + ",".join(sorts)
if clips:
clip_part += " " + " ".join(clips)
-# print 'where_part=',where_part,'clip_part',clip_part
- return (where_part,clip_part)
+ if Filter.debug:
+ logger.debug('Filter.sql: where_part={} - clip_part={}'
+ .format(where_part, clip_part))
+ return where_part, clip_part
git://git.onelab.eu / plcapi.git / blobdiff