def validate_eval(kv, p):
"""Validate a format with column values
Args:
kv (dict): column name as key, and value
p (str): format to be evaluated
Returns:
bool: True on success, otherwise False
"""
try:
s = p.format(**kv)
except KeyError as e:
raise DbProfilerException.ValidationError(_("Parameter error: ") +
"`%s' %s" % (p, kv),
rule=p,
params=kv)
try:
return eval(s)
except SyntaxError as e:
raise DbProfilerException.ValidationError(_("Syntax error: ") +
"`%s'" % s,
rule=p,
params=kv)
def validate(self, stats):
"""Validate a min/max rule based the column statistics
Args:
stats (dict): a table statistics. see Data_Structure.txt
for more info.
Returns:
True if the expression is true, otherwise False.
"""
# rule: [ column_name, expression ]
assert len(self.rule) == 2
assert 'columns' in stats
c = None
for col in stats['columns']:
if col['column_name'] == self.rule[0]:
c = col
break
if c is None:
raise DbProfilerException.ValidationError(
_("Column `%s' not found. Check your validation rule again.") %
self.rule[0], self.rule)
assert 'row_count' in stats
assert ('nulls' in c and 'min' in c and 'max' in c
and 'cardinality' in c)
kv = {
'rows': stats['row_count'],
'nulls': c['nulls'],
'min': c['min'],
'max': c['max'],
'cardinality': c['cardinality']
}
self.statistics[0] += 1
try:
s = self.rule[1].format(**kv)
except KeyError as e:
self.statistics[1] += 1
raise DbProfilerException.ValidationError(
_("Parameter error: ") + "`%s'" % kv, self.rule)
try:
if eval(s) is False:
self.statistics[1] += 1
return False
except SyntaxError:
self.statistics[1] += 1
raise DbProfilerException.ValidationError(
_("Syntax error: ") + "`%s'" % s, self.rule)
return True
def validate(self, column_names, record):
"""Validate one record
Args:
columns (list): a list of column names associated with each field.
record (list): a record, consisting of list of fields.
Returns:
True on evaluation succeeded, otherwise False.
"""
# self.rule: [ column name, format ]
assert len(self.rule) == 2
assert len(column_names) == len(record)
self.statistics[0] += 1
kv = {}
for k, v in zip(column_names, record):
# if the value is not a number, it needs to be quoted with "'".
try:
float(v)
kv[k] = v
except ValueError as e:
kv[k] = "'" + v + "'"
try:
s = self.rule[1].format(**kv)
except KeyError as e:
self.statistics[1] += 1
raise DbProfilerException.ValidationError(
_("Parameter error: ") + "`%s'" % kv, self.rule)
try:
if eval(s) is False:
self.statistics[1] += 1
return False
except SyntaxError:
self.statistics[1] += 1
raise DbProfilerException.ValidationError(
_("Syntax error: ") + "`%s'" % s, self.rule)
return True
def validate(self, dbdriver):
if dbdriver is None:
raise DbProfilerException.DriverError(
_("Database driver not found."))
try:
res = dbdriver.q2rs(self.query)
except DbProfilerException.QueryError as e:
raise DbProfilerException.ValidationError(_("SQL error: ") +
"`%s'" % self.query,
self.label,
source=e)
assert res
assert len(res.column_names) == len(res.resultset[0])
assert len(res.resultset) == 1
kv = {}
for k, v in zip(res.column_names, res.resultset[0]):
kv[k] = v
return validate_eval(kv, self.rule[2])