Merge branch '1.0-dev' into ishymko/samples

Author: ishymko

buf.gen.yaml

@@ -29,7 +29,3 @@ plugins:
   # Generates *_pb2.pyi files.
   - remote: buf.build/protocolbuffers/pyi
     out: src/a2a/types
-  # Generates a2a.swagger.json (OpenAPI v2)
-  - remote: buf.build/grpc-ecosystem/openapiv2
-    out: src/a2a/types
-    opt: json_names_for_fields=true

src/a2a/client/client_factory.py

@@ -16,6 +16,7 @@
 from a2a.client.transports.jsonrpc import JsonRpcTransport
 from a2a.client.transports.rest import RestTransport
 from a2a.client.transports.tenant_decorator import TenantTransportDecorator
+from a2a.compat.v0_3.versions import is_legacy_version
 from a2a.types.a2a_pb2 import (
     AgentCapabilities,
     AgentCard,
@@ -111,7 +112,7 @@ def jsonrpc_transport_producer(
                     else PROTOCOL_VERSION_CURRENT
                 )
 
-                if ClientFactory._is_legacy_version(version):
+                if is_legacy_version(version):
                     from a2a.compat.v0_3.jsonrpc_transport import (  # noqa: PLC0415
                         CompatJsonRpcTransport,
                     )
@@ -150,7 +151,7 @@ def rest_transport_producer(
                     else PROTOCOL_VERSION_CURRENT
                 )
 
-                if ClientFactory._is_legacy_version(version):
+                if is_legacy_version(version):
                     from a2a.compat.v0_3.rest_transport import (  # noqa: PLC0415
                         CompatRestTransport,
                     )
@@ -197,7 +198,7 @@ def grpc_transport_producer(
                 )
 
                 if (
-                    ClientFactory._is_legacy_version(version)
+                    is_legacy_version(version)
                     and CompatGrpcTransport is not None
                 ):
                     return CompatGrpcTransport.create(card, url, config)
@@ -215,21 +216,6 @@ def grpc_transport_producer(
                 grpc_transport_producer,
             )
 
-    @staticmethod
-    def _is_legacy_version(version: str | None) -> bool:
-        """Determines if the given version is a legacy protocol version (>=0.3 and <1.0)."""
-        if not version:
-            return False
-        try:
-            v = Version(version)
-            return (
-                Version(PROTOCOL_VERSION_0_3)
-                <= v
-                < Version(PROTOCOL_VERSION_1_0)
-            )
-        except InvalidVersion:
-            return False
-
     @staticmethod
     def _find_best_interface(
         interfaces: list[AgentInterface],

src/a2a/compat/v0_3/conversions.py

@@ -9,8 +9,10 @@
 from google.protobuf.json_format import MessageToDict, ParseDict
 
 from a2a.compat.v0_3 import types as types_v03
+from a2a.compat.v0_3.versions import is_legacy_version
 from a2a.server.models import PushNotificationConfigModel, TaskModel
 from a2a.types import a2a_pb2 as pb2_v10
+from a2a.utils import constants, errors
 
 
 _COMPAT_TO_CORE_TASK_STATE: dict[types_v03.TaskState, Any] = {
@@ -676,7 +678,7 @@ def to_core_agent_interface(
     return pb2_v10.AgentInterface(
         url=compat_interface.url,
         protocol_binding=compat_interface.transport,
-        protocol_version='0.3.0',  # Defaulting for legacy
+        protocol_version=constants.PROTOCOL_VERSION_0_3,  # Defaulting for legacy
     )
 
 
@@ -857,7 +859,8 @@ def to_core_agent_card(compat_card: types_v03.AgentCard) -> pb2_v10.AgentCard:
     primary_interface = pb2_v10.AgentInterface(
         url=compat_card.url,
         protocol_binding=compat_card.preferred_transport or 'JSONRPC',
-        protocol_version=compat_card.protocol_version or '0.3.0',
+        protocol_version=compat_card.protocol_version
+        or constants.PROTOCOL_VERSION_0_3,
     )
     core_card.supported_interfaces.append(primary_interface)
 
@@ -918,21 +921,23 @@ def to_core_agent_card(compat_card: types_v03.AgentCard) -> pb2_v10.AgentCard:
 def to_compat_agent_card(core_card: pb2_v10.AgentCard) -> types_v03.AgentCard:
     # Map supported interfaces back to legacy layout
     """Convert agent card to v0.3 compat type."""
-    primary_interface = (
-        core_card.supported_interfaces[0]
-        if core_card.supported_interfaces
-        else pb2_v10.AgentInterface(
-            url='', protocol_binding='JSONRPC', protocol_version='0.3.0'
+    compat_interfaces = [
+        interface
+        for interface in core_card.supported_interfaces
+        if (
+            (not interface.protocol_version)
+            or is_legacy_version(interface.protocol_version)
         )
-    )
-    additional_interfaces = (
-        [
-            to_compat_agent_interface(i)
-            for i in core_card.supported_interfaces[1:]
-        ]
-        if len(core_card.supported_interfaces) > 1
-        else None
-    )
+    ]
+    if not compat_interfaces:
+        raise errors.VersionNotSupportedError(
+            'AgentCard must have at least one interface with compatible protocol version.'
+        )
+
+    primary_interface = compat_interfaces[0]
+    additional_interfaces = [
+        to_compat_agent_interface(i) for i in compat_interfaces[1:]
+    ]
 
     compat_cap = to_compat_agent_capabilities(core_card.capabilities)
     supports_authenticated_extended_card = (
@@ -947,8 +952,9 @@ def to_compat_agent_card(core_card: pb2_v10.AgentCard) -> types_v03.AgentCard:
         version=core_card.version,
         url=primary_interface.url,
         preferred_transport=primary_interface.protocol_binding,
-        protocol_version=primary_interface.protocol_version,
-        additional_interfaces=additional_interfaces,
+        protocol_version=primary_interface.protocol_version
+        or constants.PROTOCOL_VERSION_0_3,
+        additional_interfaces=additional_interfaces or None,
         provider=to_compat_agent_provider(core_card.provider)
         if core_card.HasField('provider')
         else None,

src/a2a/compat/v0_3/versions.py

@@ -0,0 +1,18 @@
+"""Utility functions for protocol version comparison and validation."""
+
+from packaging.version import InvalidVersion, Version
+
+from a2a.utils.constants import PROTOCOL_VERSION_0_3, PROTOCOL_VERSION_1_0
+
+
+def is_legacy_version(version: str | None) -> bool:
+    """Determines if the given version is a legacy protocol version (>=0.3 and <1.0)."""
+    if not version:
+        return False
+    try:
+        v = Version(version)
+        return (
+            Version(PROTOCOL_VERSION_0_3) <= v < Version(PROTOCOL_VERSION_1_0)
+        )
+    except InvalidVersion:
+        return False

src/a2a/server/apps/jsonrpc/fastapi_app.py

@@ -1,5 +1,3 @@
-import importlib.resources
-import json
 import logging
 
 from collections.abc import Awaitable, Callable
@@ -36,43 +34,6 @@
 logger = logging.getLogger(__name__)
 
 
-class A2AFastAPI(FastAPI):
-    """A FastAPI application that adds A2A-specific OpenAPI components."""
-
-    _a2a_components_added: bool = False
-
-    def openapi(self) -> dict[str, Any]:
-        """Generates the OpenAPI schema for the application."""
-        if self.openapi_schema:
-            return self.openapi_schema
-
-        # Try to use the a2a.json schema generated from the proto file
-        # if available, instead of generating one from the python types.
-        try:
-            from a2a import types  # noqa: PLC0415
-
-            schema_file = importlib.resources.files(types).joinpath('a2a.json')
-            if schema_file.is_file():
-                self.openapi_schema = json.loads(
-                    schema_file.read_text(encoding='utf-8')
-                )
-                if self.openapi_schema:
-                    return self.openapi_schema
-        except Exception:  # noqa: BLE001
-            logger.warning(
-                "Could not load 'a2a.json' from 'a2a.types'. Falling back to auto-generation."
-            )
-
-        openapi_schema = super().openapi()
-        if not self._a2a_components_added:
-            # A2ARequest is now a Union type of proto messages, so we can't use
-            # model_json_schema. Instead, we just mark it as added without
-            # adding the schema since proto types don't have Pydantic schemas.
-            # The OpenAPI schema will still be functional for the endpoints.
-            self._a2a_components_added = True
-        return openapi_schema
-
-
 class A2AFastAPIApplication(JSONRPCApplication):
     """A FastAPI application implementing the A2A protocol server endpoints.
 
@@ -180,7 +141,7 @@ def build(
         Returns:
             A configured FastAPI application instance.
         """
-        app = A2AFastAPI(**kwargs)
+        app = FastAPI(**kwargs)
 
         self.add_routes_to_app(app, agent_card_url, rpc_url)
 

src/a2a/server/apps/rest/rest_adapter.py

@@ -39,6 +39,9 @@
 )
 from a2a.server.context import ServerCallContext
 from a2a.server.request_handlers.request_handler import RequestHandler
+from a2a.server.request_handlers.response_helpers import (
+    agent_card_to_dict,
+)
 from a2a.server.request_handlers.rest_handler import RESTHandler
 from a2a.types.a2a_pb2 import AgentCard
 from a2a.utils.error_handlers import (
@@ -175,7 +178,7 @@ async def handle_get_agent_card(
         if self.card_modifier:
             card_to_serve = await maybe_await(self.card_modifier(card_to_serve))
 
-        return MessageToDict(card_to_serve)
+        return agent_card_to_dict(card_to_serve)
 
     async def _handle_authenticated_agent_card(
         self, request: Request, call_context: ServerCallContext | None = None

src/a2a/server/request_handlers/response_helpers.py

@@ -87,8 +87,11 @@ def agent_card_to_dict(card: AgentCard) -> dict[str, Any]:
     """Convert AgentCard to dict and inject backward compatibility fields."""
     result = MessageToDict(card)
 
-    compat_card = to_compat_agent_card(card)
-    compat_dict = compat_card.model_dump(exclude_none=True)
+    try:
+        compat_card = to_compat_agent_card(card)
+        compat_dict = compat_card.model_dump(exclude_none=True)
+    except VersionNotSupportedError:
+        compat_dict = {}
 
     # Do not include supportsAuthenticatedExtendedCard if false
     if not compat_dict.get('supportsAuthenticatedExtendedCard'):