Files
sglang/sgl-model-gateway/bindings/golang/src/client.rs
T

280 lines
9.4 KiB
Rust

//! Client SDK FFI functions
use std::ffi::{CStr, CString};
use std::os::raw::{c_char};
use std::ptr;
use std::sync::Arc;
use tokio::runtime::Runtime;
use once_cell::sync::Lazy;
use uuid::Uuid;
use smg::tokenizer::create_tokenizer_from_file;
use smg::tokenizer::traits::Tokenizer;
use smg_grpc_client::sglang_scheduler::SglangSchedulerClient;
use smg::protocols::chat::ChatCompletionRequest;
use smg::routers::grpc::utils::{process_chat_messages, generate_tool_constraints};
use super::error::{SglErrorCode, set_error_message};
use super::grpc_converter::sgl_grpc_response_converter_create;
use super::tokenizer::TokenizerHandle;
use super::stream::SglangStreamHandle;
/// Global tokio runtime for async operations
static RUNTIME: Lazy<Runtime> = Lazy::new(|| {
Runtime::new().expect("Failed to create tokio runtime for client FFI")
});
/// Handle for complete client SDK (gRPC client + tokenizer)
/// This handle manages the connection to sglang and provides a complete SDK interface
pub struct SglangClientHandle {
pub(crate) client: Arc<SglangSchedulerClient>,
pub(crate) tokenizer: Arc<dyn Tokenizer>,
}
/// Handle for streaming request (includes prompt token count)
#[allow(dead_code)]
pub struct StreamRequestState {
pub(crate) prompt_tokens: i32, // Number of prompt tokens for this request
}
/// Create a new SGLang client handle
///
/// # Arguments
/// * `endpoint` - gRPC endpoint (e.g., "grpc://localhost:20000")
/// * `tokenizer_path` - Path to tokenizer directory
/// * `error_out` - Optional pointer to receive error message
///
/// # Returns
/// * Pointer to SglangClientHandle on success, null on failure
#[no_mangle]
pub unsafe extern "C" fn sgl_client_create(
endpoint: *const c_char,
tokenizer_path: *const c_char,
error_out: *mut *mut c_char,
) -> *mut SglangClientHandle {
if endpoint.is_null() || tokenizer_path.is_null() {
set_error_message(error_out, "Invalid arguments: null pointer");
return ptr::null_mut();
}
let endpoint_str = match CStr::from_ptr(endpoint).to_str() {
Ok(s) => s,
Err(_) => {
set_error_message(error_out, "Invalid UTF-8 in endpoint");
return ptr::null_mut();
}
};
let tokenizer_path_str = match CStr::from_ptr(tokenizer_path).to_str() {
Ok(s) => s,
Err(_) => {
set_error_message(error_out, "Invalid UTF-8 in tokenizer_path");
return ptr::null_mut();
}
};
// Create tokenizer
let tokenizer = match create_tokenizer_from_file(tokenizer_path_str) {
Ok(t) => t,
Err(e) => {
set_error_message(error_out, &format!("Failed to create tokenizer: {}", e));
return ptr::null_mut();
}
};
// Create gRPC client
let client = match RUNTIME.block_on(async {
SglangSchedulerClient::connect(endpoint_str).await
}) {
Ok(c) => Arc::new(c),
Err(e) => {
set_error_message(error_out, &format!("Failed to connect to endpoint: {}", e));
return ptr::null_mut();
}
};
Box::into_raw(Box::new(SglangClientHandle {
client,
tokenizer,
}))
}
/// Free a client handle
#[no_mangle]
pub unsafe extern "C" fn sgl_client_free(handle: *mut SglangClientHandle) {
if !handle.is_null() {
let _ = Box::from_raw(handle);
}
}
/// Send a chat completion request and start streaming
///
/// # Arguments
/// * `client_handle` - Client handle
/// * `request_json` - OpenAI ChatCompletionRequest as JSON string
/// * `stream_handle_out` - Pointer to receive stream handle
/// * `error_out` - Optional pointer to receive error message
///
/// # Returns
/// * SglErrorCode::Success on success, error code on failure
#[no_mangle]
pub unsafe extern "C" fn sgl_client_chat_completion_stream(
client_handle: *mut SglangClientHandle,
request_json: *const c_char,
stream_handle_out: *mut *mut SglangStreamHandle,
error_out: *mut *mut c_char,
) -> SglErrorCode {
if client_handle.is_null() || request_json.is_null() || stream_handle_out.is_null() {
set_error_message(error_out, "Invalid arguments: null pointer");
return SglErrorCode::InvalidArgument;
}
let request_str = match CStr::from_ptr(request_json).to_str() {
Ok(s) => s,
Err(_) => {
set_error_message(error_out, "Invalid UTF-8 in request_json");
return SglErrorCode::InvalidArgument;
}
};
let client_ref = &*client_handle;
let client = Arc::clone(&client_ref.client);
let tokenizer = Arc::clone(&client_ref.tokenizer);
// Parse OpenAI ChatCompletionRequest
let chat_request: ChatCompletionRequest = match serde_json::from_str(request_str) {
Ok(req) => req,
Err(e) => {
set_error_message(error_out, &format!("Failed to parse request JSON: {}", e));
return SglErrorCode::ParsingError;
}
};
// Process messages and apply chat template
let processed_messages = match process_chat_messages(&chat_request, tokenizer.as_ref()) {
Ok(msgs) => msgs,
Err(e) => {
set_error_message(error_out, &format!("Failed to process messages: {}", e));
return SglErrorCode::TokenizationError;
}
};
// Tokenize
let token_ids = match tokenizer.encode(&processed_messages.text, false) {
Ok(encoding) => encoding.token_ids().to_vec(),
Err(e) => {
set_error_message(error_out, &format!("Failed to tokenize: {}", e));
return SglErrorCode::TokenizationError;
}
};
let prompt_tokens = token_ids.len() as i32; // Save prompt token count
// Generate tool constraints if needed
let tool_constraint = if let Some(tools) = chat_request.tools.as_ref() {
match generate_tool_constraints(tools, &chat_request.tool_choice, &chat_request.model) {
Ok(Some((constraint_type, constraint_value))) => Some((constraint_type, constraint_value)),
Ok(None) => None,
Err(e) => {
set_error_message(error_out, &format!("Failed to generate tool constraints: {}", e));
return SglErrorCode::ParsingError;
}
}
} else {
None
};
// Build GenerateRequest
let request_id = format!("chatcmpl-{}", Uuid::new_v4());
let proto_request = match client.build_generate_request_from_chat(
request_id.clone(),
&chat_request,
processed_messages.text,
token_ids,
processed_messages.multimodal_inputs,
tool_constraint,
) {
Ok(req) => req,
Err(e) => {
set_error_message(error_out, &format!("Failed to build generate request: {}", e));
return SglErrorCode::ParsingError;
}
};
// Send request and get stream
let stream = match RUNTIME.block_on(async {
client.generate(proto_request).await
}) {
Ok(s) => s,
Err(e) => {
set_error_message(error_out, &format!("Failed to send request: {}", e));
return SglErrorCode::UnknownError;
}
};
// Create response converter
let tools_json = chat_request.tools.as_ref()
.and_then(|t| serde_json::to_string(t).ok())
.map(|s| CString::new(s).unwrap().into_raw());
let tool_choice_json = chat_request.tool_choice.as_ref()
.and_then(|tc| serde_json::to_string(tc).ok())
.map(|s| CString::new(s).unwrap().into_raw());
let stop_json = chat_request.stop.as_ref()
.and_then(|s| serde_json::to_string(s).ok())
.map(|s| CString::new(s).unwrap().into_raw());
let stop_token_ids_json = chat_request.stop_token_ids.as_ref()
.and_then(|ids| serde_json::to_string(ids).ok())
.map(|s| CString::new(s).unwrap().into_raw());
// Create tokenizer handle for converter (we'll create a temporary one)
let tokenizer_handle = Box::into_raw(Box::new(TokenizerHandle {
tokenizer: Arc::clone(&tokenizer),
}));
let converter = sgl_grpc_response_converter_create(
tokenizer_handle,
CString::new(chat_request.model.clone()).unwrap().as_ptr(),
CString::new(request_id.clone()).unwrap().as_ptr(),
tools_json.unwrap_or(ptr::null_mut()),
tool_choice_json.unwrap_or(ptr::null_mut()),
stop_json.unwrap_or(ptr::null_mut()),
stop_token_ids_json.unwrap_or(ptr::null_mut()),
if chat_request.skip_special_tokens { 1 } else { 0 },
error_out,
);
// Free temporary tokenizer handle (converter now owns the tokenizer)
let _ = Box::from_raw(tokenizer_handle);
if converter.is_null() {
return SglErrorCode::MemoryError;
}
// Clean up temporary CStrings
if let Some(ptr) = tools_json {
let _ = CString::from_raw(ptr);
}
if let Some(ptr) = tool_choice_json {
let _ = CString::from_raw(ptr);
}
if let Some(ptr) = stop_json {
let _ = CString::from_raw(ptr);
}
if let Some(ptr) = stop_token_ids_json {
let _ = CString::from_raw(ptr);
}
// Create converter handle and set initial_prompt_tokens immediately
let mut converter_handle = *Box::from_raw(converter);
converter_handle.initial_prompt_tokens = Some(prompt_tokens);
// Create stream handle with prompt_tokens
*stream_handle_out = Box::into_raw(Box::new(SglangStreamHandle {
stream: Arc::new(tokio::sync::Mutex::new(stream)),
converter: Arc::new(tokio::sync::Mutex::new(converter_handle)),
client: Arc::clone(&client),
prompt_tokens,
}));
SglErrorCode::Success
}