agent/agent-framework
2
0
Fork 0
mirror of https://github.com/microsoft/agent-framework.git synced 2026-06-16 21:04:09 +08:00
Code Issues Packages Projects Releases Wiki Activity

Python: Add A2A server sample (#4528)

Browse Source 
* Python: Add A2A server sample and fix client streaming bug

Add a pure Python A2A server sample so testing the A2A client no longer
requires running the .NET server. The server uses the a2a-sdk's
A2AStarletteApplication with uvicorn and supports three agent types
(invoice, policy, logistics) backed by AzureOpenAIResponsesClient.

New files:
- a2a_server.py: Main server entry point with CLI args
- agent_executor.py: Bridges a2a-sdk AgentExecutor to Agent Framework
- agent_definitions.py: Agent and AgentCard factory definitions
- invoice_data.py: Mock invoice data and query tool functions
- a2a_server.http: REST Client requests for testing

Also fixes a streaming bug in agent_with_a2a.py where async with was
used on ResponseStream which does not support the async context manager
protocol. Changed to async for to match all other samples.

Closes #4045

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* Address PR review: handle CancelledError and fix end_date filtering

- Re-raise asyncio.CancelledError before the broad exception handler
  so cooperative cancellation is not swallowed.
- Make end_date filter inclusive of the full day by comparing with
  < end + timedelta(days=1) instead of <= midnight.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

---------

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
This commit is contained in:
Giles Odigwe
2026-03-10 00:00:49 +00:00
committed by GitHub
co-authored by Copilot
parent e2f0bc814e
commit ded32f3ff8
7 changed files with 709 additions and 25 deletions
Download Patch File Download Diff File Expand all files Collapse all files
python/samples/04-hosting/a2a/README.md
+39 -16
View File
@@ -1,34 +1,57 @@
# A2A Agent Examples
This folder contains examples demonstrating how to create and use agents with the A2A (Agent2Agent) protocol from the `agent_framework` package to communicate with remote A2A agents.
This sample demonstrates how to host and consume agents using the [A2A (Agent2Agent) protocol](https://a2a-protocol.org/latest/) with the `agent_framework` package. There are two runnable entry points:
By default the A2AAgent waits for the remote agent to finish before returning (`background=False`), so long-running A2A tasks are handled transparently. For advanced scenarios where you need to poll or resubscribe to in-progress tasks using continuation tokens, see the [background responses sample](../../02-agents/background_responses.py).
| Run this file | To... |
|---------------|-------|
| **[`a2a_server.py`](a2a_server.py)** | Host an Agent Framework agent as an A2A-compliant server. |
| **[`agent_with_a2a.py`](agent_with_a2a.py)** | Connect to an A2A server and send requests (non-streaming and streaming). |
For more information about the A2A protocol specification, visit: https://a2a-protocol.org/latest/
## Examples
The remaining files are supporting modules used by the server:
| File | Description |
|------|-------------|
| [`agent_with_a2a.py`](agent_with_a2a.py) | Demonstrates agent discovery, non-streaming and streaming responses using the A2A protocol. |
| [`agent_definitions.py`](agent_definitions.py) | Agent and AgentCard factory definitions for invoice, policy, and logistics agents. |
| [`agent_executor.py`](agent_executor.py) | Bridges the a2a-sdk `AgentExecutor` interface to Agent Framework agents. |
| [`invoice_data.py`](invoice_data.py) | Mock invoice data and tool functions for the invoice agent. |
| [`a2a_server.http`](a2a_server.http) | REST Client requests for testing the server directly from VS Code. |
## Environment Variables
Make sure to set the following environment variables before running the example:
Make sure to set the following environment variables before running the examples:
### Required
- `A2A_AGENT_HOST`: URL of a single A2A agent (for simple sample, e.g., `http://localhost:5001/`)
### Required (Server)
- `AZURE_AI_PROJECT_ENDPOINT` — Your Azure AI Foundry project endpoint
- `AZURE_OPENAI_RESPONSES_DEPLOYMENT_NAME` — Model deployment name (e.g. `gpt-4o`)
### Required (Client)
- `A2A_AGENT_HOST` — URL of the A2A server (e.g. `http://localhost:5001/`)
## Quick Testing with .NET A2A Servers
## Quick Start
For quick testing and demonstration, you can use the pre-built .NET A2A servers from this repository:
All commands below should be run from this directory:
**Quick Testing Reference**: Use the .NET A2A Client Server sample at:
`..\agent-framework\dotnet\samples\05-end-to-end\A2AClientServer`
### Run Python A2A Sample
```powershell
# Simple A2A sample (single agent)
cd python/samples/04-hosting/a2a
```
### 1. Start the A2A Server
Pick an agent type and start the server (each in its own terminal):
```powershell
uv run python a2a_server.py --agent-type invoice --port 5000
uv run python a2a_server.py --agent-type policy --port 5001
uv run python a2a_server.py --agent-type logistics --port 5002
```
You can run one agent or all three — each listens on its own port.
### 2. Run the A2A Client
In a separate terminal (from the same directory), point the client at a running server:
```powershell
$env:A2A_AGENT_HOST = "http://localhost:5001/"
uv run python agent_with_a2a.py
```