🐛 The streaming output was cut off due to the truncation of Chinese characters (likely a UTF-8 encoding issue). #104
Description
Bug description
Usage Scenario: Streaming Chinese Character Reception
The following are partial logs:
Chunk 10] Event: Chunk, len=184, total=893
[Chunk 11] Event: Chunk, len=204, total=1097
[Chunk 12] Event: Chunk, len=231, total=1328
[Chunk 13] Event: Chunk, len=199, total=1527
[Chunk 14] ERROR: Web stream error for model 'gemini-2.5-flash (adapter: Gemini)'.
Cause: incomplete utf-8 byte sequence from index 6
[Chunk 15] ERROR: Web stream error for model 'gemini-2.5-flash (adapter: Gemini)'.
Cause: invalid utf-8 sequence of 1 bytes from index 0
[Chunk 16] ERROR: Web stream error for model 'gemini-2.5-flash (adapter: Gemini)'.
Cause: invalid utf-8 sequence of 1 bytes from index 0
[Chunk 17] ERROR: Web stream error for model 'gemini-2.5-flash (adapter: Gemini)'.
Cause: incomplete utf-8 byte sequence from index 3
[Chunk 18] ERROR: Web stream error for model 'gemini-2.5-flash (adapter: Gemini)'.
Cause: invalid utf-8 sequence of 1 bytes from index 0
[Chunk 19] ERROR: Web stream error for model 'gemini-2.5-flash (adapter: Gemini)'.
Cause: invalid utf-8 sequence of 1 bytes from index 0
[Chunk 20] Event: Chunk, len=191, total=1718
[Chunk 21] Event: Chunk, len=215, total=1933
[Chunk 22] Event: Chunk, len=236, total=2169
[Chunk 23] ERROR: Web stream error for model 'gemini-2.5-flash (adapter: Gemini)'.
Cause: incomplete utf-8 byte sequence from index 3
[Chunk 24] ERROR: Web stream error for model 'gemini-2.5-flash (adapter: Gemini)'.
Cause: invalid utf-8 sequence of 1 bytes from index 0
[Chunk 25] ERROR: Web stream error for model 'gemini-2.5-flash (adapter: Gemini)'.
Cause: invalid utf-8 sequence of 1 bytes from index 0
[Chunk 26] Event: Chunk, len=166, total=2335
[Chunk 27] Event: Chunk, len=198, total=2533
Follow Code：
pub async fn chat_with_context_stream_genai(
&self,
text: &str,
context: &str,
tx: tokio::sync::mpsc::UnboundedSender<Result<String, SystemError>>,
) -> Result<(), SystemError> {
use futures::StreamExt;
let chat_req =
ChatRequest::new(vec![ChatMessage::system(context), ChatMessage::user(text)]);
let chat_stream_response = self
.client
.exec_chat_stream(&self.model, chat_req, None)
.await
.map_err(|e| SystemError::LlmError(format!("Gemini stream error: {}", e)))?;
let mut stream = chat_stream_response.stream;
let mut error_log: Vec<String> = Vec::new();
let mut chunk_count = 0;
let mut total_text_len = 0;
while let Some(stream_result) = stream.next().await {
chunk_count += 1;
match stream_result {
Ok(chat_event) => {
use genai::chat::ChatStreamEvent;
match chat_event {
ChatStreamEvent::Start => {
error_log.push(format!("[Chunk {}] Event: Start", chunk_count));
}
ChatStreamEvent::Chunk(chunk) => {
let text = &chunk.content;
total_text_len += text.len();
error_log.push(format!(
"[Chunk {}] Event: Chunk, len={}, total={}",
chunk_count,
text.len(),
total_text_len
));
if !text.is_empty() {
if tx.send(Ok(text.clone())).is_err() {
return Err(SystemError::ChannelSendError(
"Stream receiver closed".to_string(),
));
}
}
}
ChatStreamEvent::ReasoningChunk(chunk) => {
let text = &chunk.content;
error_log.push(format!(
"[Chunk {}] Event: ReasoningChunk, len={}",
chunk_count,
text.len()
));
if !text.is_empty() {
if tx.send(Ok(text.clone())).is_err() {
return Err(SystemError::ChannelSendError(
"Stream receiver closed".to_string(),
));
}
}
}
ChatStreamEvent::ToolCallChunk(_) => {
error_log.push(format!("[Chunk {}] Event: ToolCallChunk", chunk_count));
}
ChatStreamEvent::End(end_data) => {
error_log.push(format!(
"[Chunk {}] Event: End, data={:?}",
chunk_count, end_data
));
break;
}
}
}
Err(e) => {
let error_msg = e.to_string();
error_log.push(format!("[Chunk {}] ERROR: {}", chunk_count, error_msg));
eprintln!("\n========== GENAI STREAM ERROR LOG ==========");
eprintln!("Model: {}", self.model);
eprintln!("Total chunks received: {}", chunk_count);
eprintln!("Total text length: {} bytes", total_text_len);
eprintln!("\n--- Event Log ---");
for log in &error_log {
eprintln!("{}", log);
}
eprintln!("\n--- Error Details ---");
eprintln!("Error type: {:?}", std::any::type_name_of_val(&e));
eprintln!("Error message: {}", error_msg);
eprintln!("=============================================\n");
let error_msg_lower = error_msg.to_lowercase();
let is_utf8_error = error_msg_lower.contains("utf-8")
|| error_msg_lower.contains("utf8")
|| (error_msg_lower.contains("invalid")
&& error_msg_lower.contains("sequence"));
if is_utf8_error {
continue;
}
let error = SystemError::LlmError(format!("Stream error: {}", e));
let _ = tx.send(Err(error.clone()));
return Err(error);
}
}
}
eprintln!("\n========== GENAI STREAM SUMMARY ==========");
eprintln!("Model: {}", self.model);
eprintln!("Total chunks: {}", chunk_count);
eprintln!("Total text length: {} bytes", total_text_len);
eprintln!("==========================================\n");
Ok(())
}
Adapter
No response
Model
No response
Suggested Resolution
No response