feat(gRPC): Add proto conversion utilities

src/a2a/utils/proto_utils.py

@@ -46,6 +46,88 @@ def dict_to_struct(dictionary: dict[str, Any]) -> struct_pb2.Struct:
     return struct
 
 
+def make_dict_serializable(value: Any) -> Any:
+    """Dict pre-processing utility: converts non-serializable values to serializable form.
+
+    Use this when you want to normalize a dictionary before dict->Struct conversion.
+
+    Args:
+        value: The value to convert.
+
+    Returns:
+        A serializable value.
+    """
+    if isinstance(value, dict):
+        return {k: make_dict_serializable(v) for k, v in value.items()}
+    if isinstance(value, list | tuple):
+        return [make_dict_serializable(item) for item in value]
+    if isinstance(value, str | int | float | bool) or value is None:
+        return value
+    return str(value)
+
+
+def normalize_large_integers_to_strings(
+    value: Any, max_safe_digits: int = 15
+) -> Any:
+    """Integer preprocessing utility: converts large integers to strings.
+
+    Use this when you want to convert large integers to strings considering
+    JavaScript's MAX_SAFE_INTEGER (2^53 - 1) limitation.
+
+    Args:
+        value: The value to convert.
+        max_safe_digits: Maximum safe integer digits (default: 15).
+
+    Returns:
+        A normalized value.
+    """
+    if isinstance(value, dict):
+        return {
+            k: normalize_large_integers_to_strings(v, max_safe_digits)
+            for k, v in value.items()
+        }
+    if isinstance(value, list | tuple):
+        return [
+            normalize_large_integers_to_strings(item, max_safe_digits)
+            for item in value
+        ]
+    if isinstance(value, int) and abs(value) > (10**max_safe_digits - 1):
+        return str(value)
+    return value
+
+
+def parse_string_integers_in_dict(value: Any, max_safe_digits: int = 15) -> Any:
+    """String post-processing utility: converts large integer strings back to integers.
+
+    Use this when you want to restore large integer strings to integers
+    after Struct->dict conversion.
+
+    Args:
+        value: The value to convert.
+        max_safe_digits: Maximum safe integer digits (default: 15).
+
+    Returns:
+        A parsed value.
+    """
+    if isinstance(value, dict):
+        return {
+            k: parse_string_integers_in_dict(v, max_safe_digits)
+            for k, v in value.items()
+        }
+    if isinstance(value, list | tuple):
+        return [
+            parse_string_integers_in_dict(item, max_safe_digits)
+            for item in value
+        ]
+    if (
+        isinstance(value, str)
+        and value.lstrip('-').isdigit()
+        and len(value.lstrip('-')) > max_safe_digits
+    ):
+        return int(value)
+    return value
+
+
 class ToProto:
     """Converts Python types to proto types."""
 

tests/utils/test_proto_utils.py

@@ -251,3 +251,260 @@ def test_none_handling(self):
         assert proto_utils.ToProto.provider(None) is None
         assert proto_utils.ToProto.security(None) is None
         assert proto_utils.ToProto.security_schemes(None) is None
+
+    def test_metadata_conversion(self):
+        """Test metadata conversion with various data types."""
+        metadata = {
+            'null_value': None,
+            'bool_value': True,
+            'int_value': 42,
+            'float_value': 3.14,
+            'string_value': 'hello',
+            'dict_value': {'nested': 'dict', 'count': 10},
+            'list_value': [1, 'two', 3.0, True, None],
+            'tuple_value': (1, 2, 3),
+            'complex_list': [
+                {'name': 'item1', 'values': [1, 2, 3]},
+                {'name': 'item2', 'values': [4, 5, 6]},
+            ],
+        }
+
+        # Convert to proto
+        proto_metadata = proto_utils.ToProto.metadata(metadata)
+        assert proto_metadata is not None
+
+        # Convert back to Python
+        roundtrip_metadata = proto_utils.FromProto.metadata(proto_metadata)
+
+        # Verify all values are preserved correctly
+        assert roundtrip_metadata['null_value'] is None
+        assert roundtrip_metadata['bool_value'] is True
+        assert roundtrip_metadata['int_value'] == 42
+        assert roundtrip_metadata['float_value'] == 3.14
+        assert roundtrip_metadata['string_value'] == 'hello'
+        assert roundtrip_metadata['dict_value']['nested'] == 'dict'
+        assert roundtrip_metadata['dict_value']['count'] == 10
+        assert roundtrip_metadata['list_value'] == [1, 'two', 3.0, True, None]
+        assert roundtrip_metadata['tuple_value'] == [
+            1,
+            2,
+            3,
+        ]  # tuples become lists
+        assert len(roundtrip_metadata['complex_list']) == 2
+        assert roundtrip_metadata['complex_list'][0]['name'] == 'item1'
+
+    def test_metadata_with_custom_objects(self):
+        """Test metadata conversion with custom objects using preprocessing utility."""
+
+        class CustomObject:
+            def __str__(self):
+                return 'custom_object_str'
+
+            def __repr__(self):
+                return 'CustomObject()'
+
+        metadata = {
+            'custom_obj': CustomObject(),
+            'list_with_custom': [1, CustomObject(), 'text'],
+            'nested_custom': {'obj': CustomObject(), 'normal': 'value'},
+        }
+
+        # Use preprocessing utility to make it serializable
+        serializable_metadata = proto_utils.make_dict_serializable(metadata)
+
+        # Convert to proto
+        proto_metadata = proto_utils.ToProto.metadata(serializable_metadata)
+        assert proto_metadata is not None
+
+        # Convert back to Python
+        roundtrip_metadata = proto_utils.FromProto.metadata(proto_metadata)
+
+        # Custom objects should be converted to strings
+        assert roundtrip_metadata['custom_obj'] == 'custom_object_str'
+        assert roundtrip_metadata['list_with_custom'] == [
+            1,
+            'custom_object_str',
+            'text',
+        ]
+        assert roundtrip_metadata['nested_custom']['obj'] == 'custom_object_str'
+        assert roundtrip_metadata['nested_custom']['normal'] == 'value'
+
+    def test_metadata_edge_cases(self):
+        """Test metadata conversion with edge cases."""
+        metadata = {
+            'empty_dict': {},
+            'empty_list': [],
+            'zero': 0,
+            'false': False,
+            'empty_string': '',
+            'unicode_string': 'string test',
+            'safe_number': 9007199254740991,  # JavaScript MAX_SAFE_INTEGER
+            'negative_number': -42,
+            'float_precision': 0.123456789,
+            'numeric_string': '12345',
+        }
+
+        # Convert to proto and back
+        proto_metadata = proto_utils.ToProto.metadata(metadata)
+        roundtrip_metadata = proto_utils.FromProto.metadata(proto_metadata)
+
+        # Verify edge cases are handled correctly
+        assert roundtrip_metadata['empty_dict'] == {}
+        assert roundtrip_metadata['empty_list'] == []
+        assert roundtrip_metadata['zero'] == 0
+        assert roundtrip_metadata['false'] is False
+        assert roundtrip_metadata['empty_string'] == ''
+        assert roundtrip_metadata['unicode_string'] == 'string test'
+        assert roundtrip_metadata['safe_number'] == 9007199254740991
+        assert roundtrip_metadata['negative_number'] == -42
+        assert abs(roundtrip_metadata['float_precision'] - 0.123456789) < 1e-10
+        assert roundtrip_metadata['numeric_string'] == '12345'
+
+    def test_make_dict_serializable(self):
+        """Test the make_dict_serializable utility function."""
+
+        class CustomObject:
+            def __str__(self):
+                return 'custom_str'
+
+        test_data = {
+            'string': 'hello',
+            'int': 42,
+            'float': 3.14,
+            'bool': True,
+            'none': None,
+            'custom': CustomObject(),
+            'list': [1, 'two', CustomObject()],
+            'tuple': (1, 2, CustomObject()),
+            'nested': {'inner_custom': CustomObject(), 'inner_normal': 'value'},
+        }
+
+        result = proto_utils.make_dict_serializable(test_data)
+
+        # Basic types should be unchanged
+        assert result['string'] == 'hello'
+        assert result['int'] == 42
+        assert result['float'] == 3.14
+        assert result['bool'] is True
+        assert result['none'] is None
+
+        # Custom objects should be converted to strings
+        assert result['custom'] == 'custom_str'
+        assert result['list'] == [1, 'two', 'custom_str']
+        assert result['tuple'] == [1, 2, 'custom_str']  # tuples become lists
+        assert result['nested']['inner_custom'] == 'custom_str'
+        assert result['nested']['inner_normal'] == 'value'
+
+    def test_normalize_large_integers_to_strings(self):
+        """Test the normalize_large_integers_to_strings utility function."""
+
+        test_data = {
+            'small_int': 42,
+            'large_int': 9999999999999999999,  # > 15 digits
+            'negative_large': -9999999999999999999,
+            'float': 3.14,
+            'string': 'hello',
+            'list': [123, 9999999999999999999, 'text'],
+            'nested': {'inner_large': 9999999999999999999, 'inner_small': 100},
+        }
+
+        result = proto_utils.normalize_large_integers_to_strings(test_data)
+
+        # Small integers should remain as integers
+        assert result['small_int'] == 42
+        assert isinstance(result['small_int'], int)
+
+        # Large integers should be converted to strings
+        assert result['large_int'] == '9999999999999999999'
+        assert isinstance(result['large_int'], str)
+        assert result['negative_large'] == '-9999999999999999999'
+        assert isinstance(result['negative_large'], str)
+
+        # Other types should be unchanged
+        assert result['float'] == 3.14
+        assert result['string'] == 'hello'
+
+        # Lists should be processed recursively
+        assert result['list'] == [123, '9999999999999999999', 'text']
+
+        # Nested dicts should be processed recursively
+        assert result['nested']['inner_large'] == '9999999999999999999'
+        assert result['nested']['inner_small'] == 100
+
+    def test_parse_string_integers_in_dict(self):
+        """Test the parse_string_integers_in_dict utility function."""
+
+        test_data = {
+            'regular_string': 'hello',
+            'numeric_string_small': '123',  # small, should stay as string
+            'numeric_string_large': '9999999999999999999',  # > 15 digits, should become int
+            'negative_large_string': '-9999999999999999999',
+            'float_string': '3.14',  # not all digits, should stay as string
+            'mixed_string': '123abc',  # not all digits, should stay as string
+            'int': 42,
+            'list': ['hello', '9999999999999999999', '123'],
+            'nested': {
+                'inner_large_string': '9999999999999999999',
+                'inner_regular': 'value',
+            },
+        }
+
+        result = proto_utils.parse_string_integers_in_dict(test_data)
+
+        # Regular strings should remain unchanged
+        assert result['regular_string'] == 'hello'
+        assert (
+            result['numeric_string_small'] == '123'
+        )  # too small, stays string
+        assert result['float_string'] == '3.14'  # not all digits
+        assert result['mixed_string'] == '123abc'  # not all digits
+
+        # Large numeric strings should be converted to integers
+        assert result['numeric_string_large'] == 9999999999999999999
+        assert isinstance(result['numeric_string_large'], int)
+        assert result['negative_large_string'] == -9999999999999999999
+        assert isinstance(result['negative_large_string'], int)
+
+        # Other types should be unchanged
+        assert result['int'] == 42
+
+        # Lists should be processed recursively
+        assert result['list'] == ['hello', 9999999999999999999, '123']
+
+        # Nested dicts should be processed recursively
+        assert result['nested']['inner_large_string'] == 9999999999999999999
+        assert result['nested']['inner_regular'] == 'value'
+
+    def test_large_integer_roundtrip_with_utilities(self):
+        """Test large integer handling with preprocessing and post-processing utilities."""
+
+        original_data = {
+            'large_int': 9999999999999999999,
+            'small_int': 42,
+            'nested': {'another_large': 12345678901234567890, 'normal': 'text'},
+        }
+
+        # Step 1: Preprocess to convert large integers to strings
+        preprocessed = proto_utils.normalize_large_integers_to_strings(
+            original_data
+        )
+
+        # Step 2: Convert to proto
+        proto_metadata = proto_utils.ToProto.metadata(preprocessed)
+        assert proto_metadata is not None
+
+        # Step 3: Convert back from proto
+        dict_from_proto = proto_utils.FromProto.metadata(proto_metadata)
+
+        # Step 4: Post-process to convert large integer strings back to integers
+        final_result = proto_utils.parse_string_integers_in_dict(
+            dict_from_proto
+        )
+
+        # Verify roundtrip preserved the original data
+        assert final_result['large_int'] == 9999999999999999999
+        assert isinstance(final_result['large_int'], int)
+        assert final_result['small_int'] == 42
+        assert final_result['nested']['another_large'] == 12345678901234567890
+        assert isinstance(final_result['nested']['another_large'], int)
+        assert final_result['nested']['normal'] == 'text'