feature: update system design and introduce easy to use decorator

python/pyproject.toml

@@ -14,6 +14,7 @@ dependencies = [
     "fastapi>=0.104.0",
     "pydantic>=2.0.0",
     "uvicorn>=0.24.0",
+    "a2a-sdk[http-server]>=0.3.4",
     "yfinance>=0.2.65",
     "tushare>=1.4.24",
     "requests>=2.32.5",

python/valuecell/core/agent/client.py

@@ -0,0 +1,81 @@
+from typing import AsyncIterator
+
+import httpx
+from a2a.client import A2ACardResolver, ClientConfig, ClientFactory
+from a2a.types import Message, Part, PushNotificationConfig, Role, TextPart
+from valuecell.utils import generate_uuid
+
+from .types import MessageResponse
+
+
+class AgentClient:
+    def __init__(self, agent_url: str, push_notification_url: str = None):
+        self.agent_url = agent_url
+        self.push_notification_url = push_notification_url
+        self._client = None
+        self._httpx_client = None
+        self._initialized = False
+
+    async def _ensure_initialized(self):
+        if not self._initialized:
+            await self._setup_client()
+            self._initialized = True
+
+    async def _setup_client(self):
+        self._httpx_client = httpx.AsyncClient(timeout=30)
+
+        config = ClientConfig(
+            httpx_client=self._httpx_client,
+            accepted_output_modes=["text"],
+        )
+
+        push_notification_configs = []
+        if self.push_notification_url:
+            push_notification_configs.append(
+                PushNotificationConfig(
+                    id=generate_uuid("pushcfg"),
+                    token="token",
+                    url=self.push_notification_url,
+                )
+            )
+            config.push_notification_configs = push_notification_configs
+            config.streaming = False
+            config.polling = True
+
+        client_factory = ClientFactory(config)
+        card_resolver = A2ACardResolver(self._httpx_client, self.agent_url)
+        card = await card_resolver.get_agent_card()
+        self._client = client_factory.create(card)
+
+    async def send_message(
+        self, text: str, context_id: str = None, exhaustive: bool = False
+    ) -> MessageResponse | AsyncIterator[MessageResponse]:
+        """Send message to Agent"""
+        await self._ensure_initialized()
+
+        message = Message(
+            role=Role.user,
+            parts=[Part(root=TextPart(text=text))],
+            message_id=generate_uuid("msg"),
+            context_id=context_id or generate_uuid("ctx"),
+        )
+
+        generator = self._client.send_message(message)
+        if exhaustive:
+            return generator
+
+        task, event = await generator.__anext__()
+        await generator.aclose()
+        return task, event
+
+    async def get_agent_card(self):
+        await self._ensure_initialized()
+        card_resolver = A2ACardResolver(self._httpx_client, self.agent_url)
+        return await card_resolver.get_agent_card()
+
+    async def close(self):
+        if self._httpx_client:
+            await self._httpx_client.aclose()
+            self._httpx_client = None
+            self._client = None
+            self._initialized = False