update:num token

router/router.go

@@ -737,38 +737,53 @@ func fetchResponseContent(ctx *gin.Context, responseBody *bufio.Reader) <-chan s
 	return contentCh
 }
 
-func NumTokensFromMessages(messages []openai.ChatCompletionMessage, model string) (num_tokens int) {
+func NumTokensFromMessages(messages []openai.ChatCompletionMessage, model string) (numTokens int) {
 	tkm, err := tiktoken.EncodingForModel(model)
 	if err != nil {
 		err = fmt.Errorf("EncodingForModel: %v", err)
-		fmt.Println(err)
+		log.Println(err)
 		return
 	}
 
-	var tokens_per_message int
-	var tokens_per_name int
-	if model == "gpt-3.5-turbo-0301" || model == "gpt-3.5-turbo" {
-		tokens_per_message = 4
-		tokens_per_name = -1
-	} else if model == "gpt-4-0314" || model == "gpt-4" {
-		tokens_per_message = 3
-		tokens_per_name = 1
-	} else {
-		fmt.Println("Warning: model not found. Using cl100k_base encoding.")
-		tokens_per_message = 3
-		tokens_per_name = 1
+	var tokensPerMessage, tokensPerName int
+
+	switch model {
+	case "gpt-3.5-turbo-0613",
+		"gpt-3.5-turbo-16k-0613",
+		"gpt-4-0314",
+		"gpt-4-32k-0314",
+		"gpt-4-0613",
+		"gpt-4-32k-0613":
+		tokensPerMessage = 3
+		tokensPerName = 1
+	case "gpt-3.5-turbo-0301":
+		tokensPerMessage = 4 // every message follows <|start|>{role/name}\n{content}<|end|>\n
+		tokensPerName = -1   // if there's a name, the role is omitted
+	default:
+		if strings.Contains(model, "gpt-3.5-turbo") {
+			log.Println("warning: gpt-3.5-turbo may update over time. Returning num tokens assuming gpt-3.5-turbo-0613.")
+			return NumTokensFromMessages(messages, "gpt-3.5-turbo-0613")
+		} else if strings.Contains(model, "gpt-4") {
+			log.Println("warning: gpt-4 may update over time. Returning num tokens assuming gpt-4-0613.")
+			return NumTokensFromMessages(messages, "gpt-4-0613")
+		} else {
+			err = fmt.Errorf("warning: unknown model [%s]. Use default calculation method converted tokens.", model)
+			log.Println(err)
+			return NumTokensFromMessages(messages, "gpt-3.5-turbo-0613")
+		}
 	}
 
 	for _, message := range messages {
-		num_tokens += tokens_per_message
-		num_tokens += len(tkm.Encode(message.Content, nil, nil))
-		// num_tokens += len(tkm.Encode(message.Role, nil, nil))
+		numTokens += tokensPerMessage
+		numTokens += len(tkm.Encode(message.Content, nil, nil))
+		numTokens += len(tkm.Encode(message.Role, nil, nil))
+		numTokens += len(tkm.Encode(message.Name, nil, nil))
 		if message.Name != "" {
-			num_tokens += tokens_per_name
+			numTokens += tokensPerName
 		}
 	}
-	num_tokens += 3
-	return num_tokens
+	numTokens += 3
+	return numTokens
 }
 
 func NumTokensFromStr(messages string, model string) (num_tokens int) {