Skip to content

GitLab

Unverified Commit 34151f17 authored by Keyang Ru's avatar Keyang Ru Committed by GitHub
Browse files

[router] Steaming support for MCP Tool Calls in OpenAI Router (#11173)

parent 6794d210
Expand all Hide whitespace changes
Inline Side-by-side
Showing with 2432 additions and 68 deletions
sgl-router/tests/common/mock_worker.rs
View file @ 34151f17
...@@ -608,29 +608,353 @@ async fn responses_handler( ...@@ -608,29 +608,353 @@ async fn responses_handler(
if is_stream { if is_stream {
let request_id = format!("resp-{}", Uuid::new_v4()); let request_id = format!("resp-{}", Uuid::new_v4());
let stream = stream::once(async move { // Check if this is an MCP tool call scenario
let chunk = json!({ let has_tools = payload
"id": request_id, .get("tools")
"object": "response", .and_then(|v| v.as_array())
"created_at": timestamp, .map(|arr| {
"model": "mock-model", arr.iter().any(|tool| {
"status": "in_progress", tool.get("type")
"output": [{ .and_then(|t| t.as_str())
"type": "message", .map(|t| t == "function")
"role": "assistant", .unwrap_or(false)
"content": [{ })
"type": "output_text", })
"text": "This is a mock responses streamed output." .unwrap_or(false);
let has_function_output = payload
.get("input")
.and_then(|v| v.as_array())
.map(|items| {
items.iter().any(|item| {
item.get("type")
.and_then(|t| t.as_str())
.map(|t| t == "function_call_output")
.unwrap_or(false)
})
})
.unwrap_or(false);
if has_tools && !has_function_output {
// First turn: emit streaming tool call events
let call_id = format!(
"call_{}",
Uuid::new_v4().to_string().split('-').next().unwrap()
);
let rid = request_id.clone();
let events = vec![
// response.created
Ok::<_, Infallible>(
Event::default().event("response.created").data(
json!({
"type": "response.created",
"response": {
"id": rid.clone(),
"object": "response",
"created_at": timestamp,
"model": "mock-model",
"status": "in_progress"
}
})
.to_string(),
),
),
// response.in_progress
Ok(Event::default().event("response.in_progress").data(
json!({
"type": "response.in_progress",
"response": {
"id": rid.clone(),
"object": "response",
"created_at": timestamp,
"model": "mock-model",
"status": "in_progress"
}
})
.to_string(),
)),
// response.output_item.added with function_tool_call
Ok(Event::default().event("response.output_item.added").data(
json!({
"type": "response.output_item.added",
"output_index": 0,
"item": {
"id": call_id.clone(),
"type": "function_tool_call",
"name": "brave_web_search",
"arguments": "",
"status": "in_progress"
}
})
.to_string(),
)),
// response.function_call_arguments.delta events
Ok(Event::default()
.event("response.function_call_arguments.delta")
.data(
json!({
"type": "response.function_call_arguments.delta",
"output_index": 0,
"item_id": call_id.clone(),
"delta": "{\"query\""
})
.to_string(),
)),
Ok(Event::default()
.event("response.function_call_arguments.delta")
.data(
json!({
"type": "response.function_call_arguments.delta",
"output_index": 0,
"item_id": call_id.clone(),
"delta": ":\"SGLang"
})
.to_string(),
)),
Ok(Event::default()
.event("response.function_call_arguments.delta")
.data(
json!({
"type": "response.function_call_arguments.delta",
"output_index": 0,
"item_id": call_id.clone(),
"delta": " router MCP"
})
.to_string(),
)),
Ok(Event::default()
.event("response.function_call_arguments.delta")
.data(
json!({
"type": "response.function_call_arguments.delta",
"output_index": 0,
"item_id": call_id.clone(),
"delta": " integration\"}"
})
.to_string(),
)),
// response.function_call_arguments.done
Ok(Event::default()
.event("response.function_call_arguments.done")
.data(
json!({
"type": "response.function_call_arguments.done",
"output_index": 0,
"item_id": call_id.clone()
})
.to_string(),
)),
// response.output_item.done
Ok(Event::default().event("response.output_item.done").data(
json!({
"type": "response.output_item.done",
"output_index": 0,
"item": {
"id": call_id.clone(),
"type": "function_tool_call",
"name": "brave_web_search",
"arguments": "{\"query\":\"SGLang router MCP integration\"}",
"status": "completed"
}
})
.to_string(),
)),
// response.completed
Ok(Event::default().event("response.completed").data(
json!({
"type": "response.completed",
"response": {
"id": rid,
"object": "response",
"created_at": timestamp,
"model": "mock-model",
"status": "completed"
}
})
.to_string(),
)),
// [DONE]
Ok(Event::default().data("[DONE]")),
];
let stream = stream::iter(events);
Sse::new(stream)
.keep_alive(KeepAlive::default())
.into_response()
} else if has_tools && has_function_output {
// Second turn: emit streaming text response
let rid = request_id.clone();
let msg_id = format!(
"msg_{}",
Uuid::new_v4().to_string().split('-').next().unwrap()
);
let events = vec![
// response.created
Ok::<_, Infallible>(
Event::default().event("response.created").data(
json!({
"type": "response.created",
"response": {
"id": rid.clone(),
"object": "response",
"created_at": timestamp,
"model": "mock-model",
"status": "in_progress"
}
})
.to_string(),
),
),
// response.in_progress
Ok(Event::default().event("response.in_progress").data(
json!({
"type": "response.in_progress",
"response": {
"id": rid.clone(),
"object": "response",
"created_at": timestamp,
"model": "mock-model",
"status": "in_progress"
}
})
.to_string(),
)),
// response.output_item.added with message
Ok(Event::default().event("response.output_item.added").data(
json!({
"type": "response.output_item.added",
"output_index": 0,
"item": {
"id": msg_id.clone(),
"type": "message",
"role": "assistant",
"content": []
}
})
.to_string(),
)),
// response.content_part.added
Ok(Event::default().event("response.content_part.added").data(
json!({
"type": "response.content_part.added",
"output_index": 0,
"item_id": msg_id.clone(),
"part": {
"type": "output_text",
"text": ""
}
})
.to_string(),
)),
// response.output_text.delta events
Ok(Event::default().event("response.output_text.delta").data(
json!({
"type": "response.output_text.delta",
"output_index": 0,
"content_index": 0,
"delta": "Tool result"
})
.to_string(),
)),
Ok(Event::default().event("response.output_text.delta").data(
json!({
"type": "response.output_text.delta",
"output_index": 0,
"content_index": 0,
"delta": " consumed;"
})
.to_string(),
)),
Ok(Event::default().event("response.output_text.delta").data(
json!({
"type": "response.output_text.delta",
"output_index": 0,
"content_index": 0,
"delta": " here is the final answer."
})
.to_string(),
)),
// response.output_text.done
Ok(Event::default().event("response.output_text.done").data(
json!({
"type": "response.output_text.done",
"output_index": 0,
"content_index": 0,
"text": "Tool result consumed; here is the final answer."
})
.to_string(),
)),
// response.output_item.done
Ok(Event::default().event("response.output_item.done").data(
json!({
"type": "response.output_item.done",
"output_index": 0,
"item": {
"id": msg_id,
"type": "message",
"role": "assistant",
"content": [{
"type": "output_text",
"text": "Tool result consumed; here is the final answer."
}]
}
})
.to_string(),
)),
// response.completed
Ok(Event::default().event("response.completed").data(
json!({
"type": "response.completed",
"response": {
"id": rid,
"object": "response",
"created_at": timestamp,
"model": "mock-model",
"status": "completed",
"usage": {
"input_tokens": 12,
"output_tokens": 7,
"total_tokens": 19
}
}
})
.to_string(),
)),
// [DONE]
Ok(Event::default().data("[DONE]")),
];
let stream = stream::iter(events);
Sse::new(stream)
.keep_alive(KeepAlive::default())
.into_response()
} else {
// Default streaming response
let stream = stream::once(async move {
let chunk = json!({
"id": request_id,
"object": "response",
"created_at": timestamp,
"model": "mock-model",
"status": "in_progress",
"output": [{
"type": "message",
"role": "assistant",
"content": [{
"type": "output_text",
"text": "This is a mock responses streamed output."
}]
}] }]
}] });
}); Ok::<_, Infallible>(Event::default().data(chunk.to_string()))
Ok::<_, Infallible>(Event::default().data(chunk.to_string())) })
}) .chain(stream::once(async { Ok(Event::default().data("[DONE]")) }));
.chain(stream::once(async { Ok(Event::default().data("[DONE]")) }));
Sse::new(stream) Sse::new(stream)
.keep_alive(KeepAlive::default()) .keep_alive(KeepAlive::default())
.into_response() .into_response()
}
} else if is_background { } else if is_background {
let rid = req_id.unwrap_or_else(|| format!("resp-{}", Uuid::new_v4())); let rid = req_id.unwrap_or_else(|| format!("resp-{}", Uuid::new_v4()));
Json(json!({ Json(json!({
......
sgl-router/tests/responses_api_test.rs
View file @ 34151f17
...@@ -765,3 +765,464 @@ async fn test_max_tool_calls_limit() { ...@@ -765,3 +765,464 @@ async fn test_max_tool_calls_limit() {
worker.stop().await; worker.stop().await;
mcp.stop().await; mcp.stop().await;
} }
/// Helper function to set up common test infrastructure for streaming MCP tests
/// Returns (mcp_server, worker, router, temp_dir)
async fn setup_streaming_mcp_test() -> (
MockMCPServer,
MockWorker,
Box<dyn sglang_router_rs::routers::RouterTrait>,
tempfile::TempDir,
) {
let mcp = MockMCPServer::start().await.expect("start mcp");
let mcp_yaml = format!(
"servers:\n - name: mock\n protocol: streamable\n url: {}\n",
mcp.url()
);
let dir = tempfile::tempdir().expect("tmpdir");
let cfg_path = dir.path().join("mcp.yaml");
std::fs::write(&cfg_path, mcp_yaml).expect("write mcp cfg");
let mut worker = MockWorker::new(MockWorkerConfig {
port: 0,
worker_type: WorkerType::Regular,
health_status: HealthStatus::Healthy,
response_delay_ms: 0,
fail_rate: 0.0,
});
let worker_url = worker.start().await.expect("start worker");
let router_cfg = RouterConfig {
mode: RoutingMode::OpenAI {
worker_urls: vec![worker_url],
},
connection_mode: ConnectionMode::Http,
policy: PolicyConfig::Random,
host: "127.0.0.1".to_string(),
port: 0,
max_payload_size: 8 * 1024 * 1024,
request_timeout_secs: 60,
worker_startup_timeout_secs: 5,
worker_startup_check_interval_secs: 1,
dp_aware: false,
api_key: None,
discovery: None,
metrics: None,
log_dir: None,
log_level: Some("info".to_string()),
request_id_headers: None,
max_concurrent_requests: 32,
queue_size: 0,
queue_timeout_secs: 5,
rate_limit_tokens_per_second: None,
cors_allowed_origins: vec![],
retry: RetryConfig::default(),
circuit_breaker: CircuitBreakerConfig::default(),
disable_retries: false,
disable_circuit_breaker: false,
health_check: HealthCheckConfig::default(),
enable_igw: false,
model_path: None,
tokenizer_path: None,
history_backend: sglang_router_rs::config::HistoryBackend::Memory,
oracle: None,
};
let ctx = AppContext::new(router_cfg, reqwest::Client::new(), 64, None).expect("ctx");
let router = RouterFactory::create_router(&Arc::new(ctx))
.await
.expect("router");
(mcp, worker, router, dir)
}
/// Parse SSE (Server-Sent Events) stream into structured events
fn parse_sse_events(body: &str) -> Vec<(Option<String>, serde_json::Value)> {
let mut events = Vec::new();
let blocks: Vec<&str> = body
.split("\n\n")
.filter(|s| !s.trim().is_empty())
.collect();
for block in blocks {
let mut event_name: Option<String> = None;
let mut data_lines: Vec<String> = Vec::new();
for line in block.lines() {
if let Some(rest) = line.strip_prefix("event:") {
event_name = Some(rest.trim().to_string());
} else if let Some(rest) = line.strip_prefix("data:") {
let data = rest.trim_start();
// Skip [DONE] marker
if data != "[DONE]" {
data_lines.push(data.to_string());
}
}
}
if !data_lines.is_empty() {
let data = data_lines.join("\n");
if let Ok(parsed) = serde_json::from_str::<serde_json::Value>(&data) {
events.push((event_name, parsed));
}
}
}
events
}
#[tokio::test]
async fn test_streaming_with_mcp_tool_calls() {
// This test verifies that streaming works with MCP tool calls:
// 1. Initial streaming request with MCP tools
// 2. Mock worker streams text, then function_call deltas
// 3. Router buffers function call, executes MCP tool
// 4. Router resumes streaming with tool results
// 5. Mock worker streams final answer
// 6. Verify SSE events are properly formatted
let (mut mcp, mut worker, router, _dir) = setup_streaming_mcp_test().await;
// Build streaming request with MCP tools
let req = ResponsesRequest {
background: false,
include: None,
input: ResponseInput::Text("search for something interesting".to_string()),
instructions: Some("Use tools when needed".to_string()),
max_output_tokens: Some(256),
max_tool_calls: Some(3),
metadata: None,
model: Some("mock-model".to_string()),
parallel_tool_calls: true,
previous_response_id: None,
reasoning: None,
service_tier: ServiceTier::Auto,
store: true,
stream: true, // KEY: Enable streaming
temperature: Some(0.7),
tool_choice: ToolChoice::Value(ToolChoiceValue::Auto),
tools: vec![ResponseTool {
r#type: ResponseToolType::Mcp,
server_url: Some(mcp.url()),
server_label: Some("mock".to_string()),
server_description: Some("Mock MCP for streaming test".to_string()),
require_approval: Some("never".to_string()),
..Default::default()
}],
top_logprobs: 0,
top_p: Some(1.0),
truncation: Truncation::Disabled,
user: None,
request_id: "resp_streaming_mcp_test".to_string(),
priority: 0,
frequency_penalty: 0.0,
presence_penalty: 0.0,
stop: None,
top_k: 50,
min_p: 0.0,
repetition_penalty: 1.0,
};
let response = router.route_responses(None, &req, None).await;
// Verify streaming response
assert_eq!(
response.status(),
axum::http::StatusCode::OK,
"Streaming request should succeed"
);
// Check Content-Type is text/event-stream
let content_type = response
.headers()
.get("content-type")
.and_then(|v| v.to_str().ok());
assert_eq!(
content_type,
Some("text/event-stream"),
"Should have SSE content type"
);
// Read the streaming body
use axum::body::to_bytes;
let response_body = response.into_body();
let body_bytes = to_bytes(response_body, usize::MAX).await.unwrap();
let body_text = String::from_utf8_lossy(&body_bytes);
println!("Streaming SSE response:\n{}", body_text);
// Parse all SSE events into structured format
let events = parse_sse_events(&body_text);
assert!(!events.is_empty(), "Should have at least one SSE event");
println!("Total parsed SSE events: {}", events.len());
// Check for [DONE] marker
let has_done_marker = body_text.contains("data: [DONE]");
assert!(has_done_marker, "Stream should end with [DONE] marker");
// Track which events we've seen
let mut found_mcp_list_tools = false;
let mut found_mcp_list_tools_in_progress = false;
let mut found_mcp_list_tools_completed = false;
let mut found_response_created = false;
let mut found_mcp_call_added = false;
let mut found_mcp_call_in_progress = false;
let mut found_mcp_call_arguments = false;
let mut found_mcp_call_arguments_done = false;
let mut found_mcp_call_done = false;
let mut found_response_completed = false;
for (event_name, data) in &events {
let event_type = data.get("type").and_then(|v| v.as_str()).unwrap_or("");
match event_type {
"response.output_item.added" => {
// Check if it's an mcp_list_tools item
if let Some(item) = data.get("item") {
if item.get("type").and_then(|v| v.as_str()) == Some("mcp_list_tools") {
found_mcp_list_tools = true;
println!("✓ Found mcp_list_tools added event");
// Verify tools array is present (should be empty in added event)
assert!(
item.get("tools").is_some(),
"mcp_list_tools should have tools array"
);
} else if item.get("type").and_then(|v| v.as_str()) == Some("mcp_call") {
found_mcp_call_added = true;
println!("✓ Found mcp_call added event");
// Verify mcp_call has required fields
assert!(item.get("name").is_some(), "mcp_call should have name");
assert_eq!(
item.get("server_label").and_then(|v| v.as_str()),
Some("mock"),
"mcp_call should have server_label"
);
}
}
}
"response.mcp_list_tools.in_progress" => {
found_mcp_list_tools_in_progress = true;
println!("✓ Found mcp_list_tools.in_progress event");
// Verify it has output_index and item_id
assert!(
data.get("output_index").is_some(),
"mcp_list_tools.in_progress should have output_index"
);
assert!(
data.get("item_id").is_some(),
"mcp_list_tools.in_progress should have item_id"
);
}
"response.mcp_list_tools.completed" => {
found_mcp_list_tools_completed = true;
println!("✓ Found mcp_list_tools.completed event");
// Verify it has output_index and item_id
assert!(
data.get("output_index").is_some(),
"mcp_list_tools.completed should have output_index"
);
assert!(
data.get("item_id").is_some(),
"mcp_list_tools.completed should have item_id"
);
}
"response.mcp_call.in_progress" => {
found_mcp_call_in_progress = true;
println!("✓ Found mcp_call.in_progress event");
// Verify it has output_index and item_id
assert!(
data.get("output_index").is_some(),
"mcp_call.in_progress should have output_index"
);
assert!(
data.get("item_id").is_some(),
"mcp_call.in_progress should have item_id"
);
}
"response.mcp_call_arguments.delta" => {
found_mcp_call_arguments = true;
println!("✓ Found mcp_call_arguments.delta event");
// Delta should include arguments payload
assert!(
data.get("delta").is_some(),
"mcp_call_arguments.delta should include delta text"
);
}
"response.mcp_call_arguments.done" => {
found_mcp_call_arguments_done = true;
println!("✓ Found mcp_call_arguments.done event");
assert!(
data.get("arguments").is_some(),
"mcp_call_arguments.done should include full arguments"
);
}
"response.output_item.done" => {
if let Some(item) = data.get("item") {
if item.get("type").and_then(|v| v.as_str()) == Some("mcp_call") {
found_mcp_call_done = true;
println!("✓ Found mcp_call done event");
// Verify mcp_call.done has output
assert!(
item.get("output").is_some(),
"mcp_call done should have output"
);
}
}
}
"response.created" => {
found_response_created = true;
println!("✓ Found response.created event");
// Verify response has required fields
assert!(
data.get("response").is_some(),
"response.created should have response object"
);
}
"response.completed" => {
found_response_completed = true;
println!("✓ Found response.completed event");
}
_ => {
println!(" Other event: {}", event_type);
}
}
if let Some(name) = event_name {
println!(" Event name: {}", name);
}
}
// Verify key events were present
println!("\n=== Event Summary ===");
println!("MCP list_tools added: {}", found_mcp_list_tools);
println!(
"MCP list_tools in_progress: {}",
found_mcp_list_tools_in_progress
);
println!(
"MCP list_tools completed: {}",
found_mcp_list_tools_completed
);
println!("Response created: {}", found_response_created);
println!("MCP call added: {}", found_mcp_call_added);
println!("MCP call in_progress: {}", found_mcp_call_in_progress);
println!("MCP call arguments delta: {}", found_mcp_call_arguments);
println!("MCP call arguments done: {}", found_mcp_call_arguments_done);
println!("MCP call done: {}", found_mcp_call_done);
println!("Response completed: {}", found_response_completed);
// Assert critical events are present
assert!(
found_mcp_list_tools,
"Should send mcp_list_tools added event at the start"
);
assert!(
found_mcp_list_tools_in_progress,
"Should send mcp_list_tools.in_progress event"
);
assert!(
found_mcp_list_tools_completed,
"Should send mcp_list_tools.completed event"
);
assert!(found_response_created, "Should send response.created event");
assert!(found_mcp_call_added, "Should send mcp_call added event");
assert!(
found_mcp_call_in_progress,
"Should send mcp_call.in_progress event"
);
assert!(found_mcp_call_done, "Should send mcp_call done event");
assert!(
found_mcp_call_arguments,
"Should send mcp_call_arguments.delta event"
);
assert!(
found_mcp_call_arguments_done,
"Should send mcp_call_arguments.done event"
);
// Verify no error events
let has_error = body_text.contains("event: error");
assert!(!has_error, "Should not have error events");
worker.stop().await;
mcp.stop().await;
}
#[tokio::test]
async fn test_streaming_multi_turn_with_mcp() {
// Test streaming with multiple tool call rounds
let (mut mcp, mut worker, router, _dir) = setup_streaming_mcp_test().await;
let req = ResponsesRequest {
background: false,
include: None,
input: ResponseInput::Text("complex query requiring multiple tool calls".to_string()),
instructions: Some("Be thorough".to_string()),
max_output_tokens: Some(512),
max_tool_calls: Some(5), // Allow multiple rounds
metadata: None,
model: Some("mock-model".to_string()),
parallel_tool_calls: true,
previous_response_id: None,
reasoning: None,
service_tier: ServiceTier::Auto,
store: true,
stream: true,
temperature: Some(0.8),
tool_choice: ToolChoice::Value(ToolChoiceValue::Auto),
tools: vec![ResponseTool {
r#type: ResponseToolType::Mcp,
server_url: Some(mcp.url()),
server_label: Some("mock".to_string()),
..Default::default()
}],
top_logprobs: 0,
top_p: Some(1.0),
truncation: Truncation::Disabled,
user: None,
request_id: "resp_streaming_multiturn_test".to_string(),
priority: 0,
frequency_penalty: 0.0,
presence_penalty: 0.0,
stop: None,
top_k: 50,
min_p: 0.0,
repetition_penalty: 1.0,
};
let response = router.route_responses(None, &req, None).await;
assert_eq!(response.status(), axum::http::StatusCode::OK);
use axum::body::to_bytes;
let body_bytes = to_bytes(response.into_body(), usize::MAX).await.unwrap();
let body_text = String::from_utf8_lossy(&body_bytes);
println!("Multi-turn streaming response:\n{}", body_text);
// Verify streaming completed successfully
assert!(body_text.contains("data: [DONE]"));
assert!(!body_text.contains("event: error"));
// Count events
let event_count = body_text
.split("\n\n")
.filter(|s| !s.trim().is_empty())
.count();
println!("Total events in multi-turn stream: {}", event_count);
assert!(event_count > 0, "Should have received streaming events");
worker.stop().await;
mcp.stop().await;
}
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment