class Class(Schema):
@match(basestring, basestring, object, many(Field))
def __init__(self, name, docs, constructor, *fields):
self.name = name
self.docs = docs
self.constructor = constructor
self.fields = OrderedDict()
for f in fields:
self.fields[f.name] = f
@match(basestring, object, many(Field))
def __init__(self, name, constructor, *fields):
self.__init__(name, "", constructor, *fields)
@match(MappingNode)
def load(self, node):
loaded = {}
for k, v in node.value:
key = k.value
if key not in self.fields:
raise SchemaError("no such field: %s\n%s" % (key, k.start_mark))
f = self.fields[key]
loaded[f.alias or f.name] = f.type.load(v)
for f in self.fields.values():
key = (f.alias or f.name)
if key not in loaded:
if f.default is REQUIRED:
raise SchemaError("required field '%s' is missing\n%s" % (f.name, node.start_mark))
else:
loaded[key] = f.default
try:
return self.constructor(**loaded)
except SchemaError, e:
raise SchemaError("%s\n\n%s" % (e, node.start_mark))
class Class(Schema):
@match(basestring, basestring, object, many(Field))
def __init__(self, name, docs, constructor, *fields, **kwargs):
self.name = name
self.docs = docs
if isinstance(constructor, Field):
fields = (constructor, ) + fields
constructor = OrderedDict
elif not callable(constructor):
raise TypeError("constructor must be callable")
self.constructor = constructor
self.fields = OrderedDict()
for f in fields:
self.fields[f.name] = f
self.strict = kwargs.pop("strict", True)
if kwargs:
raise TypeError("no such arg(s): %s" % ", ".join(kwargs.keys()))
@match(basestring, object, many(Field))
def __init__(self, name, constructor, *fields):
self.__init__(name, "", constructor, *fields)
@match(MappingNode)
def load(self, node):
loaded = {}
for k, v in node.value:
key = k.value
if key in self.fields:
f = self.fields[key]
elif self.strict:
raise SchemaError("no such field: %s\n%s" %
(key, k.start_mark))
else:
f = Field(key, Any())
loaded[f.alias or f.name] = f.type.load(v)
for f in self.fields.values():
key = (f.alias or f.name)
if key not in loaded:
if f.default is REQUIRED:
raise SchemaError("required field '%s' is missing\n%s" %
(f.name, node.start_mark))
elif f.default is not OMIT:
loaded[key] = f.default
try:
return self.constructor(**loaded)
except SchemaError, e:
raise SchemaError("%s\n\n%s" % (e, node.start_mark))
class ATest(object):
@match(str)
def __init__(self, x):
"init1"
self.x = x
self.case = 1
@match(int)
def __init__(self, y):
"init2"
self.__init__(str(y))
self.case = 2
@match(str, int)
def foo(self, x, y):
"foo1"
return 1, x, y
@match(int, str)
def foo(self, x, y):
"foo2"
return 2, x, y
@match([many(int)])
def foo(self, lst):
"foo3"
return 3, lst
class Union(Schema):
@match(many(Schema, min=1))
def __init__(self, *schemas):
self.schemas = schemas
@property
def name(self):
return "(%s)" % "|".join(s.name for s in self.schemas)
@match(Node)
def load(self, node):
for s in self.schemas:
try:
return s.load(node)
except SchemaError, e:
pass
raise SchemaError("expecting one of (%s), got %s\n%s" % ("|".join((s.name for s in self.schemas)),
node.tag, node.start_mark))
class Union(Schema):
"""Unions must be able to descriminate between their schemas. The
means to descriminate can be somewhat flexible. A descriminator is
computed according to the following algorithm:
Logically the descriminator consists of the following components:
1. The type. This is sufficient for scalar values and seqences,
but we need more to descriminate maps into distinct types.
2. For maps, a further descriminator is computed based on a
signature composed of all required fields of type Constant.
"""
@match(many(Schema, min=1))
def __init__(self, *schemas):
self.schemas = schemas
self.tags = {}
for s in self.schemas:
if isinstance(s, Class): continue
t = _tag(s)
if t in self.tags:
raise ValueError("ambiguous union: %s appears multiple times" %
t)
else:
self.tags[t] = s
self.signatures = []
self.constants = {}
for s in self.schemas:
if not isinstance(s, Class): continue
cls_sig = _sig(s)
for sig in self.signatures:
if not cls_sig.descriminates(sig):
raise ValueError("ambiguous union: %s, %s" %
(sig, cls_sig))
else:
self.signatures.append(cls_sig)
for f in s.fields.values():
if f.required and isinstance(f.type, Constant):
if f.name not in self.constants:
self.constants[f.name] = {}
if f.type.value not in self.constants[f.name]:
self.constants[f.name][f.type.value] = set()
self.constants[f.name][f.type.value].add(s)
for s in self.schemas:
if not isinstance(s, Class): continue
for f in s.fields.values():
if not isinstance(f.type,
Constant) and f.name in self.constants:
raise ValueError(
"ambiguous union: '%s' both constant and unconstrained"
% f.name)
if self.signatures and "map" in self.tags:
raise ValueError("ambiguous union: map and %s" %
", ".join(str(s) for s in self.signatures))
@property
def name(self):
return "(%s)" % "|".join(s.name for s in self.schemas)
@property
def docname(self):
return "(%s)" % "|".join(s.docname for s in self.schemas)
@match(Node)
def load(self, node):
t = _tag(node)
if self.signatures and t == "map":
candidates = set(s for s in self.schemas if isinstance(s, Class))
for k, v in node.value:
if v.tag.endswith(":map") or v.tag.endswith(":seq"): continue
if k.value in self.constants and v.value in self.constants[
k.value]:
candidates.intersection_update(
self.constants[k.value][v.value])
if len(candidates) == 1:
s = candidates.pop()
return s.load(node)
else:
raise SchemaError(
"expecting one of (%s), got %s\n%s" %
("|".join(str(s)
for s in self.signatures), t, node.start_mark))
# in case this is an union contains constant(s), and t is a 'string' of the value "foo" from the yaml,
# the user might have intended a constant named "foo".
if t not in self.tags:
v = node.value
# `v` could have an unhashable type (like 'list') which results in a type error while the `in` check
if (isinstance(v, str) or isinstance(v, unicode)):
if v not in self.tags:
raise SchemaError(
"expecting one of (%s), got %s(%s)" % ("|".join(
str(s)
for s in self.tags.keys() + self.signatures), t,
v))
return self.tags[v].load(node)
# it doesn't seem like a constant hence not fit within the union
raise SchemaError(
"expecting one of (%s), got %s" %
("|".join(str(s)
for s in self.tags.keys() + self.signatures), t))
return self.tags[t].load(node)
@property
def traversal(self):
for s in self.schemas:
for t in s.traversal:
yield t
# limitations under the License.
from yaml import ScalarNode, SequenceNode, MappingNode, CollectionNode, Node, compose, compose_all, serialize, \
serialize_all
from forge.match import choice, match, many
from StringIO import StringIO
from .schema import _scalar2py
# modes
LEAF_AS_NODE = "LEAF_AS_NODE"
LEAF_AS_PYTHON = "LEAF_AS_PYTHON"
LEAF_AS_STRING = "LEAF_AS_STRING"
@match(MappingNode, many(Node))
def traversal(node, *parents):
yield node
for k, v in node.value:
for n in traversal(k):
yield n
for n in traversal(v):
yield n
@match(SequenceNode)
def traversal(node):
yield node
for v in node.value:
for n in traversal(v):
yield n
def test_giant_switch():
OBJECT = Action("object")
BAZ = Action("Baz")
FOO_TYPE = Action("Foo")
FOO_VALUE = Action("FOO")
FOO_BAZ = Action("Foo, Baz")
FOO_OBJECT = Action("Foo, object")
OBJECT_THREE = Action("object, 3")
OBJECT_OBJECT = Action("object, object")
INTS = Action("ints")
THREES = Action("threes")
ONE_TO_FOUR = Action("1, 2, 3, 4")
LIST_OF_INT = Action("list-of-int")
LIST_OF_ZERO = Action("list-of-zero")
TUPLE_OF_INT = Action("tuple-of-int")
PAIRS = Action("PAIRS")
frag = choice(
when(object, OBJECT),
when(Baz, BAZ),
when(Foo, FOO_TYPE),
when(FOO, FOO_VALUE),
when(one(Foo, Baz), FOO_BAZ),
when(one(Foo, object), FOO_OBJECT),
when(one(Bar, 3), FOO_OBJECT),
when(one(object, 3), OBJECT_THREE),
when(one(object, object), OBJECT_OBJECT),
when(one(int, many(int)), INTS),
when(one(3, many(3)), THREES),
when(one(1, 2, 3, 4), ONE_TO_FOUR),
when([many(int)], LIST_OF_INT),
when([0], LIST_OF_ZERO),
when((int,), TUPLE_OF_INT),
when(many(str, int), PAIRS)
)
n = compile(frag)
assert n.apply(Foo()) == FOO_TYPE
assert n.apply(Bar()) == FOO_TYPE
assert n.apply(Baz()) == BAZ
assert n.apply(FOO) == FOO_VALUE
assert n.apply(Foo(), Baz()) == FOO_BAZ
assert n.apply(Foo(), 3) == FOO_OBJECT
assert n.apply(Bar(), 3) == FOO_OBJECT
assert n.apply(object(), object()) == OBJECT_OBJECT
assert n.apply(3) == THREES
assert n.apply(3, 3) == THREES
assert n.apply(3, 3, 3) == THREES
assert n.apply(3, 3, 3, 3) == THREES
assert n.apply(1, 2, 3, 4) == ONE_TO_FOUR
assert n.apply(0, 1, 2, 3) == INTS
assert n.apply([1, 2, 3, 4]*100) == LIST_OF_INT
assert n.apply([0]) == LIST_OF_ZERO
assert n.apply((0,)) == TUPLE_OF_INT
assert n.apply("one", 1, "two", 2, "three", 3) == PAIRS
try:
n.apply("one", 1, "two", 2, "three")
assert False, "expected MatchError"
except MatchError:
pass
def test_init_doc():
for i in range(1, 3):
assert "init%i" % i in ATest.__init__.__doc__
assert "init4" not in ATest.__init__.__doc__
for i in range(1, 4):
assert "init%i" % i in Sub.__init__.__doc__
def test_method_doc():
for i in range(1, 4):
assert "foo%i" % i in ATest.foo.__doc__
assert "foo5" not in ATest.foo.__doc__
for i in range(1, 5):
assert "foo%i" % i in Sub.foo.__doc__
@match(many(int))
def fdsa(*args):
return args
def test_fdsa():
assert fdsa() == ()
assert fdsa(1) == (1,)
assert fdsa(1, 2) == (1, 2)
@match(int)
def fib(n):
return fib(n-1) + fib(n-2)
@match(choice(0, 1))
def fib(n):
return n
