Files
tutor-service/internal/llm/client.go

120 lines
2.7 KiB
Go

package llm
import (
"bytes"
"context"
"encoding/json"
"fmt"
"io"
"net/http"
"strings"
"time"
)
type Client struct {
endpoint string
apiKey string
model string
httpClient *http.Client
}
func NewClient(endpoint, apiKey, model string) *Client {
return &Client{
endpoint: strings.TrimRight(endpoint, "/"),
apiKey: apiKey,
model: model,
httpClient: &http.Client{Timeout: 60 * time.Second},
}
}
type ChatMessage struct {
Role string `json:"role"`
Content string `json:"content"`
}
type chatRequest struct {
Model string `json:"model"`
Messages []ChatMessage `json:"messages"`
ResponseFormat *responseFmt `json:"response_format,omitempty"`
Temperature float64 `json:"temperature,omitempty"`
}
type responseFmt struct {
Type string `json:"type"`
}
type chatResponse struct {
Choices []struct {
Message ChatMessage `json:"message"`
} `json:"choices"`
Error *struct {
Message string `json:"message"`
Type string `json:"type"`
} `json:"error,omitempty"`
}
func (c *Client) Chat(ctx context.Context, systemPrompt, userPrompt string) (string, error) {
return c.ChatJSON(ctx, systemPrompt, userPrompt, false)
}
func (c *Client) ChatJSON(ctx context.Context, systemPrompt, userPrompt string, jsonMode bool) (string, error) {
messages := []ChatMessage{
{Role: "system", Content: systemPrompt},
{Role: "user", Content: userPrompt},
}
req := chatRequest{
Model: c.model,
Messages: messages,
}
if jsonMode {
req.ResponseFormat = &responseFmt{Type: "json_object"}
}
body, err := json.Marshal(req)
if err != nil {
return "", fmt.Errorf("marshal request: %w", err)
}
url := c.endpoint + "/v1/chat/completions"
httpReq, err := http.NewRequestWithContext(ctx, http.MethodPost, url, bytes.NewReader(body))
if err != nil {
return "", fmt.Errorf("create request: %w", err)
}
httpReq.Header.Set("Content-Type", "application/json")
if c.apiKey != "" {
httpReq.Header.Set("Authorization", "Bearer "+c.apiKey)
}
resp, err := c.httpClient.Do(httpReq)
if err != nil {
return "", fmt.Errorf("http do: %w", err)
}
defer resp.Body.Close()
respBody, err := io.ReadAll(resp.Body)
if err != nil {
return "", fmt.Errorf("read response: %w", err)
}
if resp.StatusCode != http.StatusOK {
return "", fmt.Errorf("llm api error %d: %s", resp.StatusCode, string(respBody))
}
var chatResp chatResponse
if err := json.Unmarshal(respBody, &chatResp); err != nil {
return "", fmt.Errorf("unmarshal response: %w", err)
}
if chatResp.Error != nil {
return "", fmt.Errorf("llm error: %s", chatResp.Error.Message)
}
if len(chatResp.Choices) == 0 {
return "", fmt.Errorf("no choices in response")
}
return chatResp.Choices[0].Message.Content, nil
}