feat(serialization): add two-decimal precision serialization for float fields

Added a new `serialize_f32_two_decimals` helper function to serialize Option<f32> fields with exactly two decimal places. Applied this serialization to all float fields in ChatBody (temperature, top_p, n, presence_penalty, frequency_penalty) to ensure consistent numeric formatting in API requests.

Also improved error handling in requests.rs by:
1. Adding fallback for JSON parsing errors
2. Enhancing error messages with status codes
3. Making error messages more descriptive

Signed-off-by: jinlong <jinlong@tencent.com>

Author: fslongjin

src/apis/chat.rs

@@ -7,7 +7,18 @@ use std::collections::HashMap;
 
 use crate::requests::Requests;
 use crate::*;
-use serde::{Deserialize, Serialize};
+use serde::{Deserialize, Serialize, Serializer};
+
+fn serialize_f32_two_decimals<S>(value: &Option<f32>, serializer: S) -> Result<S::Ok, S::Error>
+where
+    S: Serializer,
+{
+    match value {
+        Some(v) => serializer.serialize_f64((*v as f64 * 100.0).round() / 100.0),
+        None => serializer.serialize_none(),
+    }
+}
+
 
 use super::{completions::Completion, CHAT_COMPLETION_CREATE};
 
@@ -23,14 +34,14 @@ pub struct ChatBody {
 	/// while lower values like 0.2 will make it more focused and deterministic.
 	/// We generally recommend altering this or top_p but not both.
 	/// Defaults to 1
-	#[serde(skip_serializing_if = "Option::is_none")]
+	#[serde(skip_serializing_if = "Option::is_none", serialize_with = "serialize_f32_two_decimals")]
 	pub temperature: Option<f32>,
 	/// An alternative to sampling with temperature, called nucleus sampling,
 	/// where the model considers the results of the tokens with top_p probability mass.
 	/// So 0.1 means only the tokens comprising the top 10% probability mass are considered.
 	/// We generally recommend altering this or temperature but not both.
 	/// Defaults to 1
-	#[serde(skip_serializing_if = "Option::is_none")]
+	#[serde(skip_serializing_if = "Option::is_none", serialize_with = "serialize_f32_two_decimals")]
 	pub top_p: Option<f32>,
 	/// How many chat completion choices to generate for each input message.
 	/// Defaults to 1
@@ -55,13 +66,13 @@ pub struct ChatBody {
 	/// Positive values penalize new tokens based on whether they appear in the text so far,
 	/// increasing the model's likelihood to talk about new topics.
 	/// Defaults to 0
-	#[serde(skip_serializing_if = "Option::is_none")]
+	#[serde(skip_serializing_if = "Option::is_none", serialize_with = "serialize_f32_two_decimals")]
 	pub presence_penalty: Option<f32>,
 	/// Number between -2.0 and 2.0.
 	/// Positive values penalize new tokens based on their existing frequency in the text so far,
 	/// decreasing the model's likelihood to repeat the same line verbatim.
 	/// Defaults to 0
-	#[serde(skip_serializing_if = "Option::is_none")]
+	#[serde(skip_serializing_if = "Option::is_none", serialize_with = "serialize_f32_two_decimals")]
 	pub frequency_penalty: Option<f32>,
 	/// Modify the likelihood of specified tokens appearing in the completion.
 	/// Accepts a json object that maps tokens (specified by their token ID in the tokenizer)

src/requests.rs

@@ -70,7 +70,12 @@ fn deal_response(response: Result<ureq::Response, ureq::Error>, sub_url: &str) -
 		},
 		Err(err) => match err {
 			ureq::Error::Status(status, response) => {
-				let error_msg = response.into_json::<Json>().unwrap();
+				let mut error_msg = response
+					.into_json::<Json>()
+					.unwrap_or_else(|x| serde_json::Value::String(x.to_string()));
+				if let serde_json::Value::String(ref mut s) = error_msg {
+					*s = format!("status: {}, msg: {}", status, s);
+				}
 				error!("<== ❌\n\tError api: {sub_url}, status: {status}, error: {error_msg}");
 				return Err(Error::ApiError(format!("{error_msg}")));
 			},