msgpack: support UUID extended type

Tarantool supports UUID type since version 2.4.1 [1]. This patch
introduced the support of Tarantool UUID type in msgpack decoders and
encoders. The Tarantool UUID type is mapped to the native Python
uuid.UUID type.

1. tarantool/tarantool#4268

Closed #202

Author: DifferentialOrange

Diff for: CHANGELOG.md

@@ -8,6 +8,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 - Decimal type support (#203).
+- UUID type support (#202).
 
 ### Changed
 - Bump msgpack requirement to 1.0.4 (PR #223).

Diff for: tarantool/ext_types/packer.py

@@ -1,9 +1,17 @@
 from decimal import Decimal
+from uuid import UUID
 from msgpack import ExtType
 
 import tarantool.ext_types.decimal as ext_decimal
+import tarantool.ext_types.uuid as ext_uuid
+
+encoders = [
+    {'type': Decimal, 'ext': ext_decimal},
+    {'type': UUID,    'ext': ext_uuid   },
+]
 
 def default(obj):
-    if isinstance(obj, Decimal):
-        return ExtType(ext_decimal.EXT_ID, ext_decimal.encode(obj))
+    for encoder in encoders:
+        if isinstance(obj, encoder['type']):
+            return ExtType(encoder['ext'].EXT_ID, encoder['ext'].encode(obj))
     raise TypeError("Unknown type: %r" % (obj,))

Diff for: tarantool/ext_types/unpacker.py

@@ -1,8 +1,14 @@
 from decimal import Decimal
 
 import tarantool.ext_types.decimal as ext_decimal
+import tarantool.ext_types.uuid as ext_uuid
+
+decoders = {
+    ext_decimal.EXT_ID: ext_decimal.decode,
+    ext_uuid.EXT_ID   : ext_uuid.decode   ,
+}
 
 def ext_hook(code, data):
-    if code == ext_decimal.EXT_ID:
-        return ext_decimal.decode(data)
+    if decoders[code]:
+        return decoders[code](data)
     raise NotImplementedError("Unknown msgpack type: %d" % (code,))

Diff for: tarantool/ext_types/uuid.py

@@ -0,0 +1,17 @@
+from uuid import UUID
+
+# https://www.tarantool.io/en/doc/latest/dev_guide/internals/msgpack_extensions/#the-uuid-type
+#
+# The UUID MessagePack representation looks like this:
+# +--------+------------+-----------------+
+# | MP_EXT | MP_UUID    | UuidValue       |
+# | = d8   | = 2        | = 16-byte value |
+# +--------+------------+-----------------+
+
+EXT_ID = 2
+
+def encode(obj):
+    return obj.bytes
+
+def decode(data):
+    return UUID(bytes=data)

Diff for: test/suites/lib/skip.py

@@ -143,3 +143,14 @@ def skip_or_run_decimal_test(func):
 
     return skip_or_run_test_pcall_require(func, 'decimal',
                                       'does not support decimal type')
+
+def skip_or_run_UUID_test(func):
+    """Decorator to skip or run UUID-related tests depending on
+    the tarantool version.
+
+    Tarantool supports UUID type only since 2.4.1 version.
+    See https://github.com/tarantool/tarantool/issues/4268
+    """
+
+    return skip_or_run_test_tarantool(func, '2.4.1',
+                                      'does not support UUID type')

Diff for: test/suites/test_ext_types.py

@@ -4,12 +4,13 @@
 
 import sys
 import unittest
+import uuid
 import decimal
 import warnings
 import tarantool
 
 from .lib.tarantool_server import TarantoolServer
-from .lib.skip import skip_or_run_decimal_test
+from .lib.skip import skip_or_run_decimal_test, skip_or_run_UUID_test
 from tarantool.error import MsgpackError, MsgpackWarning
 
 class TestSuite_ExtTypes(unittest.TestCase):
@@ -24,6 +25,7 @@ def setUpClass(self):
         self.adm = self.srv.admin
         self.adm(r"""
             _, decimal = pcall(require, 'decimal')
+            _, uuid = pcall(require, 'uuid')
 
             box.schema.space.create('test')
             box.space['test']:create_index('primary', {
@@ -200,6 +202,44 @@ def test_decimal_encode_with_precision_loss(self):
                     """ % (i, decimal_case['result'])),
                     [True])
 
+
+    UUID_cases = [
+        "ae28d4f6-076c-49dd-8227-7f9fae9592d0",
+        "b3121301-9300-4038-a652-ead943fb9c39",
+        "dfa69f02-92e6-44a5-abb5-84b39292ff93",
+        "8b69a1ce-094a-4e21-a5dc-4cdae7cd8960",
+        "25932334-1d42-4686-9299-ec1a7165227c",
+    ]
+
+    @skip_or_run_UUID_test
+    def test_UUID_decode(self):
+        for i in range(len(self.UUID_cases)):
+            with self.subTest(msg=str(i)):
+                UUID_case = self.UUID_cases[i]
+
+                self.adm("box.space['test']:replace{%d, uuid.fromstr('%s')}" % (i, UUID_case))
+
+                self.assertSequenceEqual(
+                    self.con.select('test', i),
+                    [[i, uuid.UUID(UUID_case)]])
+
+    @skip_or_run_UUID_test
+    def test_UUID_encode(self):
+        for i in range(len(self.UUID_cases)):
+            with self.subTest(msg=str(i)):
+                UUID_case = self.UUID_cases[i]
+
+                self.con.insert('test', [i, uuid.UUID(UUID_case)])
+
+                self.assertSequenceEqual(
+                    self.con.eval("""
+                        local tuple = box.space['test']:get(%d)
+                        assert(tuple ~= nil)
+
+                        return tuple[2] == uuid.fromstr('%s')
+                    """ % (i, UUID_case)),
+                    [True])
+
     @classmethod
     def tearDownClass(self):
         self.con.close()