Files
zerogravity/src/api/responses.rs

1877 lines
80 KiB
Rust

//! OpenAI Responses API (/v1/responses) handler.
//!
//! Strictly adheres to the official OpenAI Responses API protocol:
//! https://platform.openai.com/docs/api-reference/responses
use axum::{
extract::State,
http::StatusCode,
response::{sse::Event, IntoResponse, Json, Sse},
};
use rand::Rng;
use std::sync::atomic::{AtomicU32, Ordering};
use std::sync::Arc;
use tracing::{debug, info, warn};
use super::models::{lookup_model, DEFAULT_MODEL, MODELS};
use super::polling::{
extract_model_usage, extract_response_text, extract_thinking_content,
extract_thinking_signature, is_response_done, poll_for_response,
};
use super::types::*;
use super::util::{err_response, now_unix, responses_sse_event, upstream_err_response};
use super::AppState;
use crate::mitm::modify::{openai_tool_choice_to_gemini, openai_tools_to_gemini};
use crate::mitm::store::PendingToolResult;
// ─── Input extraction ────────────────────────────────────────────────────────
/// Parsed tool result from function_call_output items in input.
struct ToolResultInput {
call_id: String,
output: String,
}
/// Extract user text from Responses API `input` field.
/// Also extracts any function_call_output items for tool result handling,
/// and the first inline image (base64 data URI) if present.
fn extract_responses_input(
input: &serde_json::Value,
instructions: Option<&str>,
) -> (
String,
Vec<ToolResultInput>,
Option<crate::proto::ImageData>,
) {
let mut tool_results: Vec<ToolResultInput> = Vec::new();
let mut image: Option<crate::proto::ImageData> = None;
let user_text = match input {
serde_json::Value::String(s) => s.clone(),
serde_json::Value::Array(items) => {
// Check for function_call_output items
for item in items {
if item["type"].as_str() == Some("function_call_output") {
if let (Some(call_id), Some(output)) =
(item["call_id"].as_str(), item["output"].as_str())
{
tool_results.push(ToolResultInput {
call_id: call_id.to_string(),
output: output.to_string(),
});
}
}
// Extract first image from top-level input items
if image.is_none() {
image = super::util::extract_image_from_content(item);
}
}
// If we have tool results but no text, generate a follow-up prompt
if !tool_results.is_empty() {
// Look for any text items alongside the tool results
let text_items: String = items
.iter()
.filter(|item| {
let t = item["type"].as_str().unwrap_or("");
t == "input_text" || t == "text"
})
.filter_map(|p| p["text"].as_str())
.collect::<Vec<_>>()
.join(" ");
if text_items.is_empty() {
"Use the tool results to answer the original question.".to_string()
} else {
text_items
}
} else {
// Normal input extraction
// First try: flat content parts (input_text / input_image)
let flat_text: String = items
.iter()
.filter(|item| {
let t = item["type"].as_str().unwrap_or("");
t == "input_text" || t == "text"
})
.filter_map(|p| p["text"].as_str())
.collect::<Vec<_>>()
.join(" ");
if !flat_text.is_empty() {
flat_text
} else {
// Fallback: conversation-style with role: "user"
items
.iter()
.rev()
.find(|item| item["role"].as_str() == Some("user"))
.and_then(|item| {
// Also scan content array for images
if image.is_none() {
image = super::util::extract_first_image(&item["content"]);
}
match &item["content"] {
serde_json::Value::String(s) => Some(s.clone()),
serde_json::Value::Array(parts) => Some(
parts
.iter()
.filter(|p| {
let t = p["type"].as_str().unwrap_or("");
t == "input_text" || t == "text"
})
.filter_map(|p| p["text"].as_str())
.collect::<Vec<_>>()
.join(" "),
),
_ => None,
}
})
.unwrap_or_default()
}
}
}
_ => String::new(),
};
let final_text = match instructions {
Some(inst) if !inst.is_empty() => format!("{inst}\n\n{user_text}"),
_ => user_text,
};
(final_text, tool_results, image)
}
/// Response-specific data for building a Response object.
struct ResponseData {
id: String,
model: String,
status: &'static str,
created_at: u64,
completed_at: Option<u64>,
output: Vec<serde_json::Value>,
usage: Option<Usage>,
thinking_signature: Option<String>,
}
/// Build a full Response object matching the official OpenAI schema.
fn build_response_object(data: ResponseData, params: &RequestParams) -> ResponsesResponse {
ResponsesResponse {
id: data.id,
object: "response",
created_at: data.created_at,
status: data.status,
completed_at: data.completed_at,
error: None,
incomplete_details: None,
instructions: params.instructions.clone(),
max_output_tokens: params.max_output_tokens,
model: data.model,
output: data.output,
parallel_tool_calls: true,
previous_response_id: params.previous_response_id.clone(),
reasoning: Reasoning {
effort: params.reasoning_effort.clone(),
summary: None,
},
store: params.store,
temperature: params.temperature,
text: params.text_format.clone(),
tool_choice: params.tool_choice.clone(),
tools: params.tools.clone(),
top_p: params.top_p,
truncation: "disabled",
usage: data.usage,
user: params.user.clone(),
metadata: params.metadata.clone(),
thinking_signature: data.thinking_signature,
}
}
/// Serialize a ResponsesResponse to serde_json::Value for SSE embedding.
fn response_to_json(resp: &ResponsesResponse) -> serde_json::Value {
serde_json::to_value(resp).unwrap_or(serde_json::json!({}))
}
// ─── Handler ─────────────────────────────────────────────────────────────────
pub(crate) async fn handle_responses(
State(state): State<Arc<AppState>>,
Json(body): Json<ResponsesRequest>,
) -> axum::response::Response {
info!(
"POST /v1/responses model={} stream={}",
body.model.as_deref().unwrap_or(DEFAULT_MODEL),
body.stream
);
let model_name = body.model.as_deref().unwrap_or(DEFAULT_MODEL);
let model = match lookup_model(model_name) {
Some(m) => m,
None => {
let names: Vec<&str> = MODELS.iter().map(|m| m.name).collect();
return err_response(
StatusCode::BAD_REQUEST,
format!("Unknown model: {model_name}. Available: {names:?}"),
"invalid_request_error",
);
}
};
let token = state.backend.oauth_token().await;
if token.is_empty() {
return err_response(
StatusCode::UNAUTHORIZED,
"No OAuth token. POST to /v1/token or set ZEROGRAVITY_TOKEN env var.".into(),
"authentication_error",
);
}
let (user_text, tool_results, image) =
extract_responses_input(&body.input, body.instructions.as_deref());
// Handle tool result submission (function_call_output in input)
let is_tool_result_turn = !tool_results.is_empty();
let mut pending_tool_results: Vec<PendingToolResult> = Vec::new();
if is_tool_result_turn {
for tr in &tool_results {
// For tool result turns, we use the call_id as the name directly.
// The proxy captured function calls (with real names) are paired in
// the ToolRound when we know the cascade_id later.
let name = tr.call_id.clone();
let result_value = serde_json::from_str::<serde_json::Value>(&tr.output)
.unwrap_or_else(|_| serde_json::json!({"result": tr.output}));
pending_tool_results.push(PendingToolResult {
name,
result: result_value,
});
}
info!(
count = tool_results.len(),
"Tool results for MITM injection (will build tool round after cascade_id)"
);
}
if user_text.is_empty() && !is_tool_result_turn {
return err_response(
StatusCode::BAD_REQUEST,
"No user input found".to_string(),
"invalid_request_error",
);
}
// ── Build per-request state locally ──────────────────────────────────
// Detect web_search_preview tool (OpenAI spec) → enable Google Search grounding
let has_web_search = body.tools.as_ref().is_some_and(|tools| {
tools.iter().any(|t| {
let t_type = t["type"].as_str().unwrap_or("");
t_type == "web_search_preview" || t_type == "web_search"
})
});
// Convert OpenAI tools to Gemini format
let tools = body.tools.as_ref().and_then(|t| {
let gemini_tools = openai_tools_to_gemini(t);
if gemini_tools.is_empty() {
None
} else {
info!(count = t.len(), "Client tools for MITM injection");
Some(gemini_tools)
}
});
let tool_config = body.tool_choice.as_ref().map(openai_tool_choice_to_gemini);
// Build generation params locally
let (response_mime_type, response_schema, text_format) = if let Some(ref text_val) = body.text {
let fmt_type = text_val["format"]["type"].as_str().unwrap_or("text");
if fmt_type == "json_schema" {
let name = text_val["format"]["name"].as_str().map(|s| s.to_string());
let schema = text_val["format"]["schema"]
.as_object()
.map(|o| serde_json::Value::Object(o.clone()));
let strict = text_val["format"]["strict"].as_bool();
let tf = TextFormat {
format: TextFormatInner {
format_type: "json_schema".to_string(),
name: name.clone(),
schema: schema.clone(),
strict,
},
};
(Some("application/json".to_string()), schema, tf)
} else {
(None, None, TextFormat::default())
}
} else {
(None, None, TextFormat::default())
};
use crate::mitm::store::GenerationParams;
let gp = GenerationParams {
temperature: body.temperature,
top_p: body.top_p,
top_k: None,
max_output_tokens: body.max_output_tokens,
stop_sequences: None,
frequency_penalty: None,
presence_penalty: None,
reasoning_effort: body.reasoning_effort.clone(),
response_mime_type,
response_schema,
google_search: has_web_search,
};
let generation_params = if gp.temperature.is_some()
|| gp.top_p.is_some()
|| gp.max_output_tokens.is_some()
|| gp.reasoning_effort.is_some()
|| gp.response_mime_type.is_some()
|| gp.response_schema.is_some()
|| gp.google_search
{
Some(gp)
} else {
None
};
let response_id = format!("resp_{}", uuid::Uuid::new_v4().to_string().replace('-', ""));
// Always create a new cascade for every request
let cascade_id = match state.backend.create_cascade().await {
Ok(cid) => cid,
Err(e) => {
return err_response(
StatusCode::BAD_GATEWAY,
format!("StartCascade failed: {e}"),
"server_error",
);
}
};
// Image for MITM injection
let pending_image = image.as_ref().map(|img| {
use base64::Engine;
crate::mitm::store::PendingImage {
base64_data: base64::engine::general_purpose::STANDARD.encode(&img.data),
mime_type: img.mime_type.clone(),
}
});
// Build event channel — always created for MITM response path
let (tx, rx) = tokio::sync::mpsc::channel(64);
let (mitm_rx, event_tx) = (Some(rx), tx);
// Build tool rounds now that cascade_id is known
let mut tool_rounds: Vec<crate::mitm::store::ToolRound> = Vec::new();
if is_tool_result_turn && !pending_tool_results.is_empty() {
// Get last captured function calls from the previous request context
let last_calls = state
.mitm_store
.take_function_calls(&cascade_id)
.await
.unwrap_or_default();
tool_rounds.push(crate::mitm::store::ToolRound {
calls: last_calls,
results: pending_tool_results.clone(),
});
}
// Start debug trace
let trace = state
.trace
.start(&cascade_id, "POST /v1/responses", model.name, body.stream);
if let Some(ref t) = trace {
t.set_client_request(crate::trace::ClientRequestSummary {
message_count: if is_tool_result_turn { 0 } else { 1 },
tool_count: body.tools.as_ref().map_or(0, |t| t.len()),
tool_round_count: tool_rounds.len(),
user_text_len: user_text.len(),
user_text_preview: user_text.chars().take(200).collect(),
system_prompt: body.instructions.is_some(),
has_image: image.is_some(),
})
.await;
t.start_turn().await;
}
let mitm_gate = std::sync::Arc::new(tokio::sync::Notify::new());
let mitm_gate_clone = mitm_gate.clone();
state
.mitm_store
.register_request(crate::mitm::store::RequestContext {
cascade_id: cascade_id.clone(),
pending_user_text: user_text.clone(),
event_channel: event_tx,
generation_params,
pending_image,
tools,
tool_config,
pending_tool_results,
tool_rounds,
last_function_calls: Vec::new(),
call_id_to_name: std::collections::HashMap::new(),
created_at: std::time::Instant::now(),
gate: mitm_gate_clone,
trace_handle: trace.clone(),
trace_turn: 0,
})
.await;
// Send REAL user text to LS
match state
.backend
.send_message_with_image(
&cascade_id,
&format!(".<cid:{}>", cascade_id),
model.model_enum,
image.as_ref(),
)
.await
{
Ok((200, _)) => {
let bg = Arc::clone(&state.backend);
let cid = cascade_id.clone();
tokio::spawn(async move {
let _ = bg.update_annotations(&cid).await;
});
}
Ok((status, _)) => {
state.mitm_store.remove_request(&cascade_id).await;
return err_response(
StatusCode::BAD_GATEWAY,
format!("Antigravity returned {status}"),
"server_error",
);
}
Err(e) => {
state.mitm_store.remove_request(&cascade_id).await;
return err_response(
StatusCode::BAD_GATEWAY,
format!("Send message failed: {e}"),
"server_error",
);
}
}
// Wait for MITM gate: 5s → 502 if MITM enabled
let gate_start = std::time::Instant::now();
let gate_matched =
tokio::time::timeout(std::time::Duration::from_secs(5), mitm_gate.notified()).await;
let gate_wait_ms = gate_start.elapsed().as_millis() as u64;
if gate_matched.is_err() {
if state.mitm_enabled {
state.mitm_store.remove_request(&cascade_id).await;
if let Some(ref t) = trace {
t.record_error("MITM gate timeout (5s)".to_string()).await;
t.finish("mitm_timeout").await;
}
return err_response(
StatusCode::BAD_GATEWAY,
"MITM proxy did not match request within 5s".to_string(),
"mitm_timeout",
);
}
warn!(cascade = %cascade_id, "MITM gate timeout (--no-mitm mode)");
} else {
debug!(cascade = %cascade_id, gate_wait_ms, "MITM gate signaled — request matched");
if let Some(ref t) = trace {
t.record_mitm_match(0, gate_wait_ms).await;
}
}
// Capture request params for response building
let req_params = RequestParams {
user_text: user_text.clone(),
instructions: body.instructions.clone(),
store: body.store,
temperature: body.temperature.unwrap_or(1.0),
top_p: body.top_p.unwrap_or(1.0),
max_output_tokens: body.max_output_tokens,
previous_response_id: body.previous_response_id.clone(),
user: body.user.clone(),
metadata: body.metadata.clone().unwrap_or(serde_json::json!({})),
max_tool_calls: body.max_tool_calls,
reasoning_effort: body.reasoning_effort.clone(),
tool_choice: body
.tool_choice
.clone()
.unwrap_or(serde_json::json!("auto")),
tools: body.tools.clone().unwrap_or_default(),
text_format,
};
if body.stream {
handle_responses_stream(
state,
response_id,
model_name.to_string(),
cascade_id,
body.timeout,
req_params,
mitm_rx,
trace,
)
.await
} else {
handle_responses_sync(
state,
response_id,
model_name.to_string(),
cascade_id,
body.timeout,
req_params,
mitm_rx,
trace,
)
.await
}
}
/// Captured request parameters needed to echo back in the response.
struct RequestParams {
user_text: String,
instructions: Option<String>,
store: bool,
temperature: f64,
top_p: f64,
max_output_tokens: Option<u64>,
previous_response_id: Option<String>,
user: Option<String>,
metadata: serde_json::Value,
max_tool_calls: Option<u32>,
reasoning_effort: Option<String>,
tool_choice: serde_json::Value,
tools: Vec<serde_json::Value>,
text_format: TextFormat,
}
/// Build Usage from the best available source, and extract thinking text from MITM:
/// 1. MITM intercepted data (real API tokens, including cache stats + thinking text)
/// 2. LS trajectory data (real tokens, no cache info)
/// 3. Estimation from text lengths (fallback)
///
/// Returns (Usage, Option<thinking_text>). The LS strips thinking text from steps,
/// so we capture it from the raw MITM-intercepted API response.
async fn usage_from_poll(
mitm_store: &crate::mitm::store::MitmStore,
cascade_id: &str,
model_usage: &Option<super::polling::ModelUsage>,
input_text: &str,
output_text: &str,
) -> (Usage, Option<String>) {
// Priority 1: MITM intercepted data (most accurate — includes cache tokens + thinking text)
// Try exact cascade_id match first, then fall back to "_latest" (unmatched).
//
// Race condition: The LS makes TWO Google API calls for thinking models:
// Call 1: response + thinking token count (recorded first)
// Call 2: thinking summary text (merged into Call 1 by the store)
// We may read the usage after Call 1 but before Call 2 arrives.
// If we see thinking tokens but no text, wait briefly for the merge.
let keys_to_try: Vec<&str> = vec![cascade_id, "_latest"];
let mut mitm_usage = None;
for key in &keys_to_try {
if let Some(u) = mitm_store.peek_usage(key).await {
if u.thinking_output_tokens > 0 && u.thinking_text.is_none() {
// Call 2 hasn't arrived yet — wait briefly for the merge
tracing::debug!(
"MITM: thinking tokens found but no text, waiting for summary merge..."
);
for _ in 0..10 {
tokio::time::sleep(tokio::time::Duration::from_millis(100)).await;
if let Some(u2) = mitm_store.peek_usage(key).await {
if u2.thinking_text.is_some() {
break;
}
}
}
}
mitm_usage = mitm_store.take_usage(key).await;
break;
}
}
if let Some(mitm_usage) = mitm_usage {
tracing::debug!(
input = mitm_usage.input_tokens,
output = mitm_usage.output_tokens,
cache_read = mitm_usage.cache_read_input_tokens,
cache_create = mitm_usage.cache_creation_input_tokens,
thinking = mitm_usage.thinking_output_tokens,
thinking_text_len = mitm_usage.thinking_text.as_ref().map_or(0, |t| t.len()),
"Using MITM intercepted usage"
);
let thinking_text = mitm_usage.thinking_text;
let usage = Usage {
input_tokens: mitm_usage.input_tokens,
input_tokens_details: InputTokensDetails {
cached_tokens: mitm_usage.cache_read_input_tokens,
},
output_tokens: mitm_usage.output_tokens,
output_tokens_details: OutputTokensDetails {
reasoning_tokens: mitm_usage.thinking_output_tokens,
},
total_tokens: mitm_usage.input_tokens + mitm_usage.output_tokens,
};
return (usage, thinking_text);
}
// Priority 2: LS trajectory data (from CHECKPOINT/metadata steps)
if let Some(u) = model_usage {
return (
Usage {
input_tokens: u.input_tokens,
input_tokens_details: InputTokensDetails { cached_tokens: 0 },
output_tokens: u.output_tokens,
output_tokens_details: OutputTokensDetails {
reasoning_tokens: 0,
},
total_tokens: u.input_tokens + u.output_tokens,
},
None,
);
}
// Priority 3: Estimate from text lengths
(Usage::estimate(input_text, output_text), None)
}
// ─── Sync response ───────────────────────────────────────────────────────────
#[allow(clippy::too_many_arguments)]
async fn handle_responses_sync(
state: Arc<AppState>,
response_id: String,
model_name: String,
cascade_id: String,
timeout: u64,
params: RequestParams,
mitm_rx: Option<tokio::sync::mpsc::Receiver<crate::mitm::store::MitmEvent>>,
trace: Option<crate::trace::TraceHandle>,
) -> axum::response::Response {
let created_at = now_unix();
// Clear stale captured response and upstream errors (only if no pre-installed channel)
if mitm_rx.is_none() {
state.mitm_store.clear_response_async().await;
state.mitm_store.clear_upstream_error().await;
}
// ── MITM bypass: channel-based pipeline when custom tools active ──
if let Some(mut rx) = mitm_rx {
let start = std::time::Instant::now();
let mut acc_text = String::new();
let mut acc_thinking: Option<String> = None;
let mut _last_usage: Option<crate::mitm::store::ApiUsage> = None;
while let Some(event) = tokio::time::timeout(
std::time::Duration::from_secs(timeout.saturating_sub(start.elapsed().as_secs())),
rx.recv(),
)
.await
.ok()
.flatten()
{
use crate::mitm::store::MitmEvent;
match event {
MitmEvent::ThinkingDelta(t) => {
acc_thinking = Some(t);
}
MitmEvent::TextDelta(t) => {
acc_text = t;
}
MitmEvent::Usage(u) => {
_last_usage = Some(u);
}
MitmEvent::Grounding(_) => {} // stored by proxy directly
MitmEvent::FunctionCall(raw_calls) => {
let calls: Vec<_> = if let Some(max) = params.max_tool_calls {
raw_calls.iter().take(max as usize).collect()
} else {
raw_calls.iter().collect()
};
let mut output_items: Vec<serde_json::Value> = Vec::new();
for fc in &calls {
let call_id = format!(
"call_{}",
&uuid::Uuid::new_v4().to_string().replace('-', "")[..24]
);
state
.mitm_store
.register_call_id(&cascade_id, call_id.clone(), fc.name.clone())
.await;
let arguments = serde_json::to_string(&fc.args).unwrap_or_default();
output_items
.push(build_function_call_output(&call_id, &fc.name, &arguments));
}
let (usage, _) = usage_from_poll(
&state.mitm_store,
&cascade_id,
&None,
&params.user_text,
"",
)
.await;
state.mitm_store.remove_request(&cascade_id).await;
// Record trace before usage is moved
if let Some(ref t) = trace {
let fc_summaries: Vec<crate::trace::FunctionCallSummary> = calls
.iter()
.map(|fc| crate::trace::FunctionCallSummary {
name: fc.name.clone(),
args_preview: serde_json::to_string(&fc.args)
.unwrap_or_default()
.chars()
.take(200)
.collect(),
})
.collect();
t.record_response(
0,
crate::trace::ResponseSummary {
text_len: 0,
thinking_len: 0,
text_preview: String::new(),
finish_reason: Some("tool_calls".to_string()),
function_calls: fc_summaries,
grounding: false,
},
)
.await;
t.set_usage(crate::trace::TrackedUsage {
input_tokens: usage.input_tokens,
output_tokens: usage.output_tokens,
thinking_tokens: usage.output_tokens_details.reasoning_tokens,
cache_read: usage.input_tokens_details.cached_tokens,
})
.await;
t.finish("tool_call").await;
}
let resp = build_response_object(
ResponseData {
id: response_id,
model: model_name,
status: "completed",
created_at,
completed_at: Some(now_unix()),
output: output_items,
usage: Some(usage),
thinking_signature: None,
},
&params,
);
return Json(resp).into_response();
}
MitmEvent::ResponseComplete => {
if acc_text.is_empty() && acc_thinking.is_none() {
// Empty response — continue waiting
continue;
}
if acc_text.is_empty() && acc_thinking.is_some() {
// Thinking-only — LS needs to make a follow-up request.
// Reinstall channel and unblock gate.
let (new_tx, new_rx) = tokio::sync::mpsc::channel(64);
state.mitm_store.set_channel(&cascade_id, new_tx).await;
let _ = state.mitm_store.take_any_function_calls().await;
rx = new_rx;
debug!(
"Responses sync: thinking-only — new channel for follow-up, thinking_len={}",
acc_thinking.as_ref().map(|t| t.len()).unwrap_or(0)
);
continue;
}
let (usage, _) = usage_from_poll(
&state.mitm_store,
&cascade_id,
&None,
&params.user_text,
&acc_text,
)
.await;
state.mitm_store.remove_request(&cascade_id).await;
let mut output_items: Vec<serde_json::Value> = Vec::new();
if let Some(ref t) = acc_thinking {
output_items.push(build_reasoning_output(t));
}
let msg_id =
format!("msg_{}", uuid::Uuid::new_v4().to_string().replace('-', ""));
output_items.push(build_message_output(&msg_id, &acc_text));
// Record trace before usage is moved
if let Some(ref t) = trace {
t.record_response(
0,
crate::trace::ResponseSummary {
text_len: acc_text.len(),
thinking_len: acc_thinking.as_ref().map_or(0, |s| s.len()),
text_preview: acc_text.chars().take(200).collect(),
finish_reason: Some("stop".to_string()),
function_calls: Vec::new(),
grounding: false,
},
)
.await;
t.set_usage(crate::trace::TrackedUsage {
input_tokens: usage.input_tokens,
output_tokens: usage.output_tokens,
thinking_tokens: usage.output_tokens_details.reasoning_tokens,
cache_read: usage.input_tokens_details.cached_tokens,
})
.await;
t.finish("completed").await;
}
let resp = build_response_object(
ResponseData {
id: response_id,
model: model_name,
status: "completed",
created_at,
completed_at: Some(now_unix()),
output: output_items,
usage: Some(usage),
thinking_signature: None,
},
&params,
);
return Json(resp).into_response();
}
MitmEvent::UpstreamError(err) => {
state.mitm_store.remove_request(&cascade_id).await;
if let Some(ref t) = trace {
t.record_error(format!(
"Upstream: {}",
err.message.as_deref().unwrap_or("unknown")
))
.await;
t.finish("upstream_error").await;
}
return upstream_err_response(&err);
}
}
}
// Timeout
state.mitm_store.remove_request(&cascade_id).await;
if let Some(ref t) = trace {
t.record_error(format!("Timeout: {}s", timeout)).await;
t.finish("timeout").await;
}
return err_response(
StatusCode::GATEWAY_TIMEOUT,
format!("Timeout: no response from Google API after {timeout}s"),
"upstream_error",
);
}
// ── Normal LS path (no custom tools) ──
let poll_result = poll_for_response(&state, &cascade_id, timeout).await;
if let Some(ref err) = poll_result.upstream_error {
return upstream_err_response(err);
}
let completed_at = now_unix();
let msg_id = format!("msg_{}", uuid::Uuid::new_v4().to_string().replace('-', ""));
// Check for captured function calls from MITM (clears the active flag)
let captured_tool_calls = state.mitm_store.take_function_calls(&cascade_id).await;
// Enforce max_tool_calls limit
let captured_tool_calls = captured_tool_calls.map(|mut calls| {
if let Some(max) = params.max_tool_calls {
calls.truncate(max as usize);
}
calls
});
// If we have captured tool calls, return them as function_call output items
if let Some(ref calls) = captured_tool_calls {
info!(
count = calls.len(),
tools = ?calls.iter().map(|c| &c.name).collect::<Vec<_>>(),
"Returning captured function calls to client"
);
let mut output_items: Vec<serde_json::Value> = Vec::new();
for fc in calls {
let call_id = format!(
"call_{}",
&uuid::Uuid::new_v4().to_string().replace('-', "")[..24]
);
// Register call_id → name mapping for tool result routing
state
.mitm_store
.register_call_id(&cascade_id, call_id.clone(), fc.name.clone())
.await;
// Stringify args (OpenAI sends arguments as JSON string)
let arguments = serde_json::to_string(&fc.args).unwrap_or_default();
output_items.push(build_function_call_output(&call_id, &fc.name, &arguments));
}
let (usage, _) = usage_from_poll(
&state.mitm_store,
&cascade_id,
&poll_result.usage,
&params.user_text,
&poll_result.text,
)
.await;
// Record trace before usage is moved
if let Some(ref t) = trace {
let fc_summaries: Vec<crate::trace::FunctionCallSummary> = calls
.iter()
.map(|fc| crate::trace::FunctionCallSummary {
name: fc.name.clone(),
args_preview: serde_json::to_string(&fc.args)
.unwrap_or_default()
.chars()
.take(200)
.collect(),
})
.collect();
t.record_response(
0,
crate::trace::ResponseSummary {
text_len: poll_result.text.len(),
thinking_len: poll_result.thinking.as_ref().map_or(0, |s| s.len()),
text_preview: String::new(),
finish_reason: Some("tool_calls".to_string()),
function_calls: fc_summaries,
grounding: false,
},
)
.await;
t.set_usage(crate::trace::TrackedUsage {
input_tokens: usage.input_tokens,
output_tokens: usage.output_tokens,
thinking_tokens: usage.output_tokens_details.reasoning_tokens,
cache_read: usage.input_tokens_details.cached_tokens,
})
.await;
t.finish("tool_call").await;
}
let resp = build_response_object(
ResponseData {
id: response_id,
model: model_name,
status: "completed",
created_at,
completed_at: Some(completed_at),
output: output_items,
usage: Some(usage),
thinking_signature: poll_result.thinking_signature,
},
&params,
);
return Json(resp).into_response();
}
// Normal text response (no tool calls)
let (usage, mitm_thinking) = usage_from_poll(
&state.mitm_store,
&cascade_id,
&poll_result.usage,
&params.user_text,
&poll_result.text,
)
.await;
// Thinking text priority: MITM-captured (raw API) > LS-extracted (steps)
let thinking_text = mitm_thinking.or(poll_result.thinking);
// Build output array: [reasoning (if present), message]
let mut output_items: Vec<serde_json::Value> = Vec::new();
if let Some(ref thinking) = thinking_text {
output_items.push(build_reasoning_output(thinking));
}
output_items.push(build_message_output(&msg_id, &poll_result.text));
// Record trace before usage is moved
if let Some(ref t) = trace {
t.record_response(
0,
crate::trace::ResponseSummary {
text_len: poll_result.text.len(),
thinking_len: thinking_text.as_ref().map_or(0, |s| s.len()),
text_preview: poll_result.text.chars().take(200).collect(),
finish_reason: Some("stop".to_string()),
function_calls: Vec::new(),
grounding: false,
},
)
.await;
t.set_usage(crate::trace::TrackedUsage {
input_tokens: usage.input_tokens,
output_tokens: usage.output_tokens,
thinking_tokens: usage.output_tokens_details.reasoning_tokens,
cache_read: usage.input_tokens_details.cached_tokens,
})
.await;
t.finish("completed").await;
}
let resp = build_response_object(
ResponseData {
id: response_id,
model: model_name,
status: "completed",
created_at,
completed_at: Some(completed_at),
output: output_items,
usage: Some(usage),
thinking_signature: poll_result.thinking_signature,
},
&params,
);
Json(resp).into_response()
}
// ─── Streaming response ─────────────────────────────────────────────────────
#[allow(clippy::too_many_arguments)]
async fn handle_responses_stream(
state: Arc<AppState>,
response_id: String,
model_name: String,
cascade_id: String,
timeout: u64,
params: RequestParams,
mitm_rx: Option<tokio::sync::mpsc::Receiver<crate::mitm::store::MitmEvent>>,
trace: Option<crate::trace::TraceHandle>,
) -> axum::response::Response {
let stream = async_stream::stream! {
let msg_id = format!("msg_{}", uuid::Uuid::new_v4().to_string().replace('-', ""));
let created_at = now_unix();
let seq = AtomicU32::new(0);
let next_seq = || seq.fetch_add(1, Ordering::Relaxed);
const CONTENT_IDX: u32 = 0;
// Build the in-progress response shell (no output yet)
let in_progress_resp = build_response_object(
ResponseData {
id: response_id.clone(),
model: model_name.clone(),
status: "in_progress",
created_at,
completed_at: None,
output: vec![],
usage: None,
thinking_signature: None,
},
&params,
);
let resp_json = response_to_json(&in_progress_resp);
// 1. response.created
yield Ok::<_, std::convert::Infallible>(responses_sse_event(
"response.created",
serde_json::json!({
"type": "response.created",
"sequence_number": next_seq(),
"response": resp_json,
}),
));
// 2. response.in_progress
yield Ok(responses_sse_event(
"response.in_progress",
serde_json::json!({
"type": "response.in_progress",
"sequence_number": next_seq(),
"response": resp_json,
}),
));
// ── Stream cascade updates: event-driven instead of timer-based polling ──
let start = std::time::Instant::now();
let mut last_text = String::new();
let mut thinking_emitted = false;
let mut thinking_text: Option<String> = None;
let mut message_started = false;
let reasoning_id = format!("rs_{}", uuid::Uuid::new_v4().to_string().replace('-', ""));
// Clear stale response (only if no pre-installed channel)
if mitm_rx.is_none() {
state.mitm_store.clear_response_async().await;
state.mitm_store.clear_upstream_error().await;
}
// ── MITM bypass mode (when custom tools are active) ──
// Channel-based pipeline: read events directly from MITM proxy.
// Channel is pre-installed before send_message to avoid race conditions.
if let Some(mut rx) = mitm_rx {
let mut last_thinking = String::new();
while let Some(event) = tokio::time::timeout(
std::time::Duration::from_secs(timeout.saturating_sub(start.elapsed().as_secs())),
rx.recv(),
).await.ok().flatten() {
use crate::mitm::store::MitmEvent;
match event {
MitmEvent::ThinkingDelta(full_thinking) => {
if !thinking_emitted && full_thinking.len() > last_thinking.len() {
// First thinking text — emit reasoning output_item.added
if last_thinking.is_empty() {
yield Ok(responses_sse_event(
"response.output_item.added",
serde_json::json!({
"type": "response.output_item.added",
"sequence_number": next_seq(),
"output_index": 0,
"item": {
"id": &reasoning_id,
"type": "reasoning",
"summary": [],
},
}),
));
yield Ok(responses_sse_event(
"response.reasoning_summary_part.added",
serde_json::json!({
"type": "response.reasoning_summary_part.added",
"sequence_number": next_seq(),
"item_id": &reasoning_id,
"output_index": 0,
"summary_index": 0,
"part": { "type": "summary_text", "text": "" },
}),
));
}
let delta = &full_thinking[last_thinking.len()..];
if !delta.is_empty() {
yield Ok(responses_sse_event(
"response.reasoning_summary_text.delta",
serde_json::json!({
"type": "response.reasoning_summary_text.delta",
"sequence_number": next_seq(),
"item_id": &reasoning_id,
"output_index": 0,
"summary_index": 0,
"delta": delta,
}),
));
}
last_thinking = full_thinking;
}
}
MitmEvent::TextDelta(full_text) => {
if full_text.len() > last_text.len() {
// Finalize thinking if started but not done
if !thinking_emitted && !last_thinking.is_empty() {
thinking_emitted = true;
thinking_text = Some(last_thinking.clone());
yield Ok(responses_sse_event(
"response.reasoning_summary_text.done",
serde_json::json!({
"type": "response.reasoning_summary_text.done",
"sequence_number": next_seq(),
"item_id": &reasoning_id,
"output_index": 0,
"summary_index": 0,
"text": &last_thinking,
}),
));
yield Ok(responses_sse_event(
"response.reasoning_summary_part.done",
serde_json::json!({
"type": "response.reasoning_summary_part.done",
"sequence_number": next_seq(),
"item_id": &reasoning_id,
"output_index": 0,
"summary_index": 0,
"part": { "type": "summary_text", "text": &last_thinking },
}),
));
yield Ok(responses_sse_event(
"response.output_item.done",
serde_json::json!({
"type": "response.output_item.done",
"sequence_number": next_seq(),
"output_index": 0,
"item": {
"id": &reasoning_id,
"type": "reasoning",
"summary": [{
"type": "summary_text",
"text": &last_thinking,
}],
},
}),
));
}
let msg_output_index: u32 = if thinking_emitted { 1 } else { 0 };
if !message_started {
message_started = true;
yield Ok(responses_sse_event(
"response.output_item.added",
serde_json::json!({
"type": "response.output_item.added",
"sequence_number": next_seq(),
"output_index": msg_output_index,
"item": build_message_output_in_progress(&msg_id),
}),
));
yield Ok(responses_sse_event(
"response.content_part.added",
serde_json::json!({
"type": "response.content_part.added",
"sequence_number": next_seq(),
"output_index": msg_output_index,
"content_index": CONTENT_IDX,
"part": {
"type": "output_text",
"text": "",
"annotations": [],
}
}),
));
}
let delta = &full_text[last_text.len()..];
if !delta.is_empty() {
let msg_output_index: u32 = if thinking_emitted { 1 } else { 0 };
yield Ok(responses_sse_event(
"response.output_text.delta",
serde_json::json!({
"type": "response.output_text.delta",
"sequence_number": next_seq(),
"item_id": &msg_id,
"output_index": msg_output_index,
"content_index": CONTENT_IDX,
"delta": delta,
}),
));
last_text = full_text;
}
}
}
MitmEvent::FunctionCall(raw_calls) => {
let calls: Vec<_> = if let Some(max) = params.max_tool_calls {
raw_calls.iter().take(max as usize).collect()
} else {
raw_calls.iter().collect()
};
let msg_output_index: u32 = if thinking_emitted { 1 } else { 0 };
for (i, fc) in calls.iter().enumerate() {
let call_id = format!(
"call_{}",
&uuid::Uuid::new_v4().to_string().replace('-', "")[..24]
);
let arguments = serde_json::to_string(&fc.args).unwrap_or_default();
state.mitm_store.register_call_id(&cascade_id, call_id.clone(), fc.name.clone()).await;
let fc_item_id = format!("fc_{}", uuid::Uuid::new_v4().to_string().replace('-', ""));
yield Ok(responses_sse_event(
"response.output_item.added",
serde_json::json!({
"type": "response.output_item.added",
"sequence_number": next_seq(),
"output_index": msg_output_index as usize + i,
"item": {
"id": &fc_item_id,
"type": "function_call",
"call_id": &call_id,
"name": &fc.name,
"arguments": &arguments,
"status": "completed",
},
}),
));
yield Ok(responses_sse_event(
"response.output_item.done",
serde_json::json!({
"type": "response.output_item.done",
"sequence_number": next_seq(),
"output_index": msg_output_index as usize + i,
"item": {
"id": &fc_item_id,
"type": "function_call",
"call_id": &call_id,
"name": &fc.name,
"arguments": &arguments,
"status": "completed",
},
}),
));
}
// Build output for final response
let mut output_items: Vec<serde_json::Value> = Vec::new();
for fc in &calls {
let call_id = format!(
"call_{}",
&uuid::Uuid::new_v4().to_string().replace('-', "")[..24]
);
let arguments = serde_json::to_string(&fc.args).unwrap_or_default();
output_items.push(build_function_call_output(&call_id, &fc.name, &arguments));
}
let (usage, _) = usage_from_poll(
&state.mitm_store, &cascade_id, &None,
&params.user_text, "",
).await;
// Save trace usage before move
let trace_usage = crate::trace::TrackedUsage {
input_tokens: usage.input_tokens,
output_tokens: usage.output_tokens,
thinking_tokens: usage.output_tokens_details.reasoning_tokens,
cache_read: usage.input_tokens_details.cached_tokens,
};
let final_resp = build_response_object(
ResponseData {
id: response_id.clone(),
model: model_name.clone(),
status: "completed",
created_at,
completed_at: Some(now_unix()),
output: output_items,
usage: Some(usage),
thinking_signature: None,
},
&params,
);
yield Ok(responses_sse_event(
"response.completed",
serde_json::json!({
"type": "response.completed",
"sequence_number": next_seq(),
"response": response_to_json(&final_resp),
}),
));
if let Some(ref t) = trace {
let fc_summaries: Vec<crate::trace::FunctionCallSummary> = calls.iter().map(|fc| crate::trace::FunctionCallSummary {
name: fc.name.clone(), args_preview: serde_json::to_string(&fc.args).unwrap_or_default().chars().take(200).collect(),
}).collect();
t.record_response(0, crate::trace::ResponseSummary {
text_len: 0, thinking_len: last_thinking.len(),
text_preview: String::new(),
finish_reason: Some("tool_calls".to_string()),
function_calls: fc_summaries, grounding: false,
}).await;
t.set_usage(trace_usage).await;
t.finish("tool_call").await;
}
state.mitm_store.remove_request(&cascade_id).await;
return;
}
MitmEvent::ResponseComplete => {
if !last_text.is_empty() {
let msg_idx: u32 = if thinking_emitted { 1 } else { 0 };
let (usage, _) = usage_from_poll(
&state.mitm_store, &cascade_id, &None,
&params.user_text, &last_text,
).await;
let tc = thinking_text.clone();
for evt in completion_events(
&response_id, &model_name, &msg_id, &reasoning_id,
msg_idx, CONTENT_IDX, &last_text, usage,
created_at, &seq, &params, None, tc,
) {
yield Ok(evt);
}
if let Some(ref t) = trace {
t.record_response(0, crate::trace::ResponseSummary {
text_len: last_text.len(),
thinking_len: thinking_text.as_ref().map_or(0, |s| s.len()),
text_preview: last_text.chars().take(200).collect(),
finish_reason: Some("stop".to_string()),
function_calls: Vec::new(), grounding: false,
}).await;
t.finish("completed").await;
}
state.mitm_store.remove_request(&cascade_id).await;
return;
} else if !last_thinking.is_empty() {
// Thinking-only response — LS needs follow-up API calls.
// Create a new channel and unblock the gate.
let (new_tx, new_rx) = tokio::sync::mpsc::channel(64);
state.mitm_store.set_channel(&cascade_id, new_tx).await;
let _ = state.mitm_store.take_any_function_calls().await;
rx = new_rx;
debug!(
"Responses stream: thinking-only — new channel for follow-up, thinking_len={}",
last_thinking.len()
);
}
// ResponseComplete with no text and no thinking — continue waiting
}
MitmEvent::UpstreamError(err) => {
let error_msg = super::util::upstream_error_message(&err);
let error_type = super::util::upstream_error_type(&err);
yield Ok(responses_sse_event(
"response.failed",
serde_json::json!({
"type": "response.failed",
"sequence_number": next_seq(),
"response": {
"id": &response_id,
"status": "failed",
"error": {
"type": error_type,
"message": error_msg,
"code": err.status,
},
},
}),
));
if let Some(ref t) = trace {
t.record_error(format!("Upstream: {}", error_msg)).await;
t.finish("upstream_error").await;
}
state.mitm_store.remove_request(&cascade_id).await;
return;
}
MitmEvent::Usage(_) | MitmEvent::Grounding(_) => {
// Usage/grounding stored by proxy, consumed via usage_from_poll
}
}
}
// Timeout in channel mode
state.mitm_store.remove_request(&cascade_id).await;
yield Ok(responses_sse_event(
"response.failed",
serde_json::json!({
"type": "response.failed",
"sequence_number": next_seq(),
"response": {
"id": &response_id,
"status": "failed",
"error": {
"type": "upstream_error",
"message": format!("Timeout: no response from Google API after {timeout}s"),
"code": 504,
},
},
}),
));
if let Some(ref t) = trace {
t.record_error(format!("Timeout: {timeout}s")).await;
t.finish("timeout").await;
}
return;
}
// ── Normal LS path (no custom tools) ──
// Try to open a reactive streaming connection for real-time notifications.
let mut reactive_rx = match state.backend.stream_cascade_updates(&cascade_id).await {
Ok(rx) => {
debug!("Using reactive streaming for cascade updates");
Some(rx)
}
Err(e) => {
debug!("Reactive streaming unavailable, falling back to polling: {e}");
None
}
};
let mut thinking_started = false;
let mut thinking_done = false;
let mut last_thinking_len: usize = 0;
while start.elapsed().as_secs() < timeout {
// Check for upstream errors from MITM (Google API errors)
if let Some(err) = state.mitm_store.take_upstream_error().await {
let error_msg = super::util::upstream_error_message(&err);
let error_type = super::util::upstream_error_type(&err);
yield Ok(responses_sse_event(
"response.failed",
serde_json::json!({
"type": "response.failed",
"sequence_number": next_seq(),
"response": {
"id": &response_id,
"status": "failed",
"error": {
"type": error_type,
"message": error_msg,
"code": err.status,
},
},
}),
));
break;
}
if let Ok((status, data)) = state.backend.get_steps(&cascade_id).await {
if status == 200 {
if let Some(steps) = data["steps"].as_array() {
// ── Phase 1: Stream thinking deltas progressively ──
if let Some(tc) = extract_thinking_content(steps) {
if !thinking_started {
// First time we see thinking — emit structure events
thinking_started = true;
yield Ok(responses_sse_event(
"response.output_item.added",
serde_json::json!({
"type": "response.output_item.added",
"sequence_number": next_seq(),
"output_index": 0,
"item": {
"id": &reasoning_id,
"type": "reasoning",
"summary": [],
},
}),
));
yield Ok(responses_sse_event(
"response.reasoning_summary_part.added",
serde_json::json!({
"type": "response.reasoning_summary_part.added",
"sequence_number": next_seq(),
"item_id": &reasoning_id,
"output_index": 0,
"summary_index": 0,
"part": { "type": "summary_text", "text": "" },
}),
));
}
// Emit delta if thinking text has grown
if tc.len() > last_thinking_len {
let delta = &tc[last_thinking_len..];
last_thinking_len = tc.len();
thinking_text = Some(tc.clone());
yield Ok(responses_sse_event(
"response.reasoning_summary_text.delta",
serde_json::json!({
"type": "response.reasoning_summary_text.delta",
"sequence_number": next_seq(),
"item_id": &reasoning_id,
"output_index": 0,
"summary_index": 0,
"delta": delta,
}),
));
}
}
// ── Phase 2: Stream text deltas ──
let text = extract_response_text(steps);
let msg_output_index: u32 = if thinking_started { 1 } else { 0 };
if !text.is_empty() && text != last_text {
// Finalize thinking when response text first appears
if thinking_started && !thinking_done {
thinking_done = true;
let final_thinking = thinking_text.clone().unwrap_or_default();
yield Ok(responses_sse_event(
"response.reasoning_summary_text.done",
serde_json::json!({
"type": "response.reasoning_summary_text.done",
"sequence_number": next_seq(),
"item_id": &reasoning_id,
"output_index": 0,
"summary_index": 0,
"text": &final_thinking,
}),
));
yield Ok(responses_sse_event(
"response.reasoning_summary_part.done",
serde_json::json!({
"type": "response.reasoning_summary_part.done",
"sequence_number": next_seq(),
"item_id": &reasoning_id,
"output_index": 0,
"summary_index": 0,
"part": { "type": "summary_text", "text": &final_thinking },
}),
));
yield Ok(responses_sse_event(
"response.output_item.done",
serde_json::json!({
"type": "response.output_item.done",
"sequence_number": next_seq(),
"output_index": 0,
"item": {
"id": &reasoning_id,
"type": "reasoning",
"summary": [{
"type": "summary_text",
"text": &final_thinking,
}],
},
}),
));
}
// Emit message output_item.added on first text
if !message_started {
message_started = true;
yield Ok(responses_sse_event(
"response.output_item.added",
serde_json::json!({
"type": "response.output_item.added",
"sequence_number": next_seq(),
"output_index": msg_output_index,
"item": build_message_output_in_progress(&msg_id),
}),
));
yield Ok(responses_sse_event(
"response.content_part.added",
serde_json::json!({
"type": "response.content_part.added",
"sequence_number": next_seq(),
"output_index": msg_output_index,
"content_index": CONTENT_IDX,
"part": {
"type": "output_text",
"text": "",
"annotations": [],
}
}),
));
}
let new_content = if text.len() > last_text.len()
&& text.starts_with(&*last_text)
{
&text[last_text.len()..]
} else {
&text
};
if !new_content.is_empty() {
yield Ok(responses_sse_event(
"response.output_text.delta",
serde_json::json!({
"type": "response.output_text.delta",
"sequence_number": next_seq(),
"item_id": &msg_id,
"output_index": msg_output_index,
"content_index": CONTENT_IDX,
"delta": new_content,
}),
));
last_text = text.to_string();
}
}
// ── Check completion ──
if is_response_done(steps) && !last_text.is_empty() {
debug!("Response done, text length={}", last_text.len());
let mu = extract_model_usage(steps);
let msg_idx: u32 = if thinking_started { 1 } else { 0 };
let (usage, mitm_thinking) = usage_from_poll(&state.mitm_store, &cascade_id, &mu, &params.user_text, &last_text).await;
let ts = extract_thinking_signature(steps);
// Use already-captured thinking, or MITM thinking, or LS thinking
let tc = thinking_text.clone()
.or(mitm_thinking)
.or_else(|| extract_thinking_content(steps));
for evt in completion_events(
&response_id, &model_name, &msg_id, &reasoning_id,
msg_idx, CONTENT_IDX, &last_text, usage,
created_at, &seq, &params, ts, tc,
) {
yield Ok(evt);
}
return;
}
// IDLE fallback
let step_count = steps.len();
if step_count > 4 && step_count % 5 == 0 {
if let Ok((ts, td)) = state.backend.get_trajectory(&cascade_id).await {
if ts == 200 {
let run_status = td["status"].as_str().unwrap_or("");
if run_status.contains("IDLE") && !last_text.is_empty() {
debug!("Trajectory IDLE, text length={}", last_text.len());
let mu = extract_model_usage(steps);
let msg_idx: u32 = if thinking_started { 1 } else { 0 };
let (usage, mitm_thinking) = usage_from_poll(&state.mitm_store, &cascade_id, &mu, &params.user_text, &last_text).await;
let ts = extract_thinking_signature(steps);
let tc = thinking_text.clone()
.or(mitm_thinking)
.or_else(|| extract_thinking_content(steps));
for evt in completion_events(
&response_id, &model_name, &msg_id, &reasoning_id,
msg_idx, CONTENT_IDX, &last_text, usage,
created_at, &seq, &params, ts, tc,
) {
yield Ok(evt);
}
return;
}
}
}
}
}
}
}
// Wait for next update: either reactive notification or fallback timer
match reactive_rx {
Some(ref mut rx) => {
// Wait for reactive notification with a safety timeout
let timeout = tokio::time::timeout(
tokio::time::Duration::from_millis(500),
rx.recv(),
).await;
match timeout {
Ok(Some(_diff)) => {
// Drain any additional queued notifications (coalesce)
while rx.try_recv().is_ok() {}
}
Ok(None) => {
// Stream closed — fall back to polling
debug!("Reactive stream closed, falling back to polling");
reactive_rx = None;
}
Err(_) => {} // timeout — fetch anyway as safety net
}
}
None => {
// Fallback: timer-based polling
let poll_ms: u64 = rand::thread_rng().gen_range(150..250);
tokio::time::sleep(tokio::time::Duration::from_millis(poll_ms)).await;
}
}
}
// Timeout — emit error, not fake incomplete response
yield Ok(responses_sse_event(
"response.failed",
serde_json::json!({
"type": "response.failed",
"sequence_number": next_seq(),
"response": {
"id": &response_id,
"status": "failed",
"error": {
"type": "upstream_error",
"message": format!("Timeout: no response from Google API after {timeout}s"),
"code": 504,
},
},
}),
));
};
Sse::new(stream)
.keep_alive(
axum::response::sse::KeepAlive::new()
.interval(std::time::Duration::from_secs(15))
.text(""),
)
.into_response()
}
// ─── SSE completion events ───────────────────────────────────────────────────
/// Build the final SSE events at completion time.
///
/// Reasoning events were already streamed during polling (when thinking
/// appeared in LS steps before response text). Message output_item.added
/// and content_part.added were also emitted when text first appeared.
///
/// This function emits only the "done" events plus the final response.completed.
#[allow(clippy::too_many_arguments)]
fn completion_events(
resp_id: &str,
model: &str,
msg_id: &str,
reasoning_id: &str,
msg_output_index: u32,
content_idx: u32,
text: &str,
usage: Usage,
created_at: u64,
seq: &AtomicU32,
params: &RequestParams,
thinking_signature: Option<String>,
thinking: Option<String>,
) -> Vec<Event> {
let next_seq = || seq.fetch_add(1, Ordering::Relaxed);
let completed_at = now_unix();
let output_item = build_message_output(msg_id, text);
// Build output array: [reasoning (if present), message]
let mut output_items: Vec<serde_json::Value> = Vec::new();
if let Some(ref thinking_text) = thinking {
output_items.push(serde_json::json!({
"id": reasoning_id,
"type": "reasoning",
"summary": [{
"type": "summary_text",
"text": thinking_text,
}],
}));
}
output_items.push(build_message_output(msg_id, text));
let completed_resp = build_response_object(
ResponseData {
id: resp_id.to_string(),
model: model.to_string(),
status: "completed",
created_at,
completed_at: Some(completed_at),
output: output_items,
usage: Some(usage),
thinking_signature,
},
params,
);
let mut events: Vec<Event> = Vec::new();
// Message done events
events.push(responses_sse_event(
"response.output_text.done",
serde_json::json!({
"type": "response.output_text.done",
"sequence_number": next_seq(),
"item_id": msg_id,
"output_index": msg_output_index,
"content_index": content_idx,
"text": text,
}),
));
events.push(responses_sse_event(
"response.content_part.done",
serde_json::json!({
"type": "response.content_part.done",
"sequence_number": next_seq(),
"output_index": msg_output_index,
"content_index": content_idx,
"part": { "type": "output_text", "text": text, "annotations": [] },
}),
));
events.push(responses_sse_event(
"response.output_item.done",
serde_json::json!({
"type": "response.output_item.done",
"sequence_number": next_seq(),
"output_index": msg_output_index,
"item": output_item,
}),
));
events.push(responses_sse_event(
"response.completed",
serde_json::json!({
"type": "response.completed",
"sequence_number": next_seq(),
"response": response_to_json(&completed_resp),
}),
));
events
}