mistral-go-sdk/request.go

package mistral

import (
	"bytes"
	"context"
	"encoding/json"
	"fmt"
	"io"
	"mime/multipart"
	"net/http"
)

func (c *Client) do(ctx context.Context, method, path string, body io.Reader) (*http.Response, error) {
	req, err := http.NewRequestWithContext(ctx, method, c.baseURL+path, body)
	if err != nil {
		return nil, fmt.Errorf("mistral: create request: %w", err)
	}
	req.Header.Set("Authorization", "Bearer "+c.apiKey)
	req.Header.Set("Accept", "application/json")
	if body != nil {
		req.Header.Set("Content-Type", "application/json")
	}
	resp, err := c.httpClient.Do(req)
	if err != nil {
		return nil, fmt.Errorf("mistral: send request: %w", err)
	}
	return resp, nil
}

func (c *Client) doJSON(ctx context.Context, method, path string, reqBody, respBody any) error {
	var body io.Reader
	if reqBody != nil {
		data, err := json.Marshal(reqBody)
		if err != nil {
			return fmt.Errorf("mistral: marshal request: %w", err)
		}
		body = bytes.NewReader(data)
	}
	resp, err := c.do(ctx, method, path, body)
	if err != nil {
		return err
	}
	defer resp.Body.Close()
	if resp.StatusCode >= 400 {
		return parseAPIError(resp)
	}
	if respBody != nil {
		if err := json.NewDecoder(resp.Body).Decode(respBody); err != nil {
			return fmt.Errorf("mistral: decode response: %w", err)
		}
	}
	return nil
}

func (c *Client) doStream(ctx context.Context, method, path string, reqBody any) (*http.Response, error) {
	var body io.Reader
	if reqBody != nil {
		data, err := json.Marshal(reqBody)
		if err != nil {
			return nil, fmt.Errorf("mistral: marshal request: %w", err)
		}
		body = bytes.NewReader(data)
	}
	resp, err := c.do(ctx, method, path, body)
	if err != nil {
		return nil, err
	}
	if resp.StatusCode >= 400 {
		defer resp.Body.Close()
		return nil, parseAPIError(resp)
	}
	return resp, nil
}

func (c *Client) doMultipart(ctx context.Context, path string, filename string, file io.Reader, fields map[string]string, respBody any) error {
	var buf bytes.Buffer
	w := multipart.NewWriter(&buf)
	part, err := w.CreateFormFile("file", filename)
	if err != nil {
		return fmt.Errorf("mistral: create form file: %w", err)
	}
	if _, err := io.Copy(part, file); err != nil {
		return fmt.Errorf("mistral: copy file data: %w", err)
	}
	for k, v := range fields {
		if err := w.WriteField(k, v); err != nil {
			return fmt.Errorf("mistral: write field %s: %w", k, err)
		}
	}
	if err := w.Close(); err != nil {
		return fmt.Errorf("mistral: close multipart: %w", err)
	}

	req, err := http.NewRequestWithContext(ctx, "POST", c.baseURL+path, &buf)
	if err != nil {
		return fmt.Errorf("mistral: create request: %w", err)
	}
	req.Header.Set("Authorization", "Bearer "+c.apiKey)
	req.Header.Set("Accept", "application/json")
	req.Header.Set("Content-Type", w.FormDataContentType())

	resp, err := c.httpClient.Do(req)
	if err != nil {
		return fmt.Errorf("mistral: send request: %w", err)
	}
	defer resp.Body.Close()
	if resp.StatusCode >= 400 {
		return parseAPIError(resp)
	}
	if respBody != nil {
		if err := json.NewDecoder(resp.Body).Decode(respBody); err != nil {
			return fmt.Errorf("mistral: decode response: %w", err)
		}
	}
	return nil
}

func parseAPIError(resp *http.Response) error {
	body, err := io.ReadAll(resp.Body)
	if err != nil {
		return &APIError{
			StatusCode: resp.StatusCode,
			Message:    fmt.Sprintf("failed to read error response: %v", err),
		}
	}
	var envelope struct {
		Detail  string `json:"detail"`
		Message string `json:"message"`
		Type    string `json:"type"`
		Param   string `json:"param"`
		Code    string `json:"code"`
	}
	if err := json.Unmarshal(body, &envelope); err == nil {
		msg := envelope.Message
		if msg == "" {
			msg = envelope.Detail
		}
		if msg == "" {
			msg = string(body)
		}
		return &APIError{
			StatusCode: resp.StatusCode,
			Type:       envelope.Type,
			Message:    msg,
			Param:      envelope.Param,
			Code:       envelope.Code,
		}
	}
	return &APIError{
		StatusCode: resp.StatusCode,
		Message:    string(body),
	}
}