优化封面获取细节，并复用请求

crawler.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"bytes"
+	"context"
 	"errors"
 	"fmt"
 	"github.com/spf13/viper"
@@ -15,6 +16,7 @@ import (
 	"path/filepath"
 	"strconv"
 	"strings"
+	"time"
 	"unicode"
 )
 
@@ -22,6 +24,7 @@ type Crawler struct {
 	avPath     string
 	outputPath string
 	config     *viper.Viper
+	client     *http.Client
 }
 
 func NewCrawler(avPath, outputPath string) *Crawler {
@@ -38,6 +41,14 @@ func NewCrawler(avPath, outputPath string) *Crawler {
 		avPath:     avPath,
 		outputPath: outputPath,
 		config:     config,
+		client: &http.Client{
+			Timeout: 15 * time.Second,
+			Transport: &http.Transport{
+				MaxIdleConns:       10,
+				IdleConnTimeout:    30 * time.Second,
+				DisableCompression: true,
+			},
+		},
 	}
 }
 
@@ -119,31 +130,50 @@ func (c *Crawler) getCoverCodeList(files []string) (coverList []string) {
 func (c *Crawler) fetchCoverImg(code string) error {
 	imgUrl := strings.ReplaceAll(c.config.GetString("crawler.url"), `*`, code)
 	suffix := filepath.Ext(imgUrl)
-	nameSlice := strings.Split(code, "00")
 
-	if len(nameSlice) < 2 {
+	offset := 0
+	// 如果第一个字符为 '1'，则从下一个字符开始查找
+	if len(code) > 0 && code[0] == '1' {
+		offset = 1
+	}
+
+	// 获取号码所在的位置
+	index := strings.Index(code[offset:], "00")
+	if index == -1 {
 		return nil
 	}
 
-	if len(nameSlice[0]) > 4 {
-		nameSlice[0] = nameSlice[0][1:]
+	// 分隔字母部分及数字部分
+	letters := code[:index]
+	num := code[index+2:]
+	if offset > 0 {
+		letters = code[1:index]
 	}
 
 	fileName := filepath.Join(c.outputPath, fmt.Sprintf("%s-%s%s",
-		strings.ToUpper(nameSlice[0]),
-		nameSlice[1],
+		strings.ToUpper(letters),
+		num,
 		suffix,
 	))
 
-	req, err := http.NewRequest("GET", imgUrl, nil)
+	// 使用带超时的上下文
+	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+	defer cancel()
+
+	req, err := http.NewRequestWithContext(ctx, "GET", imgUrl, nil)
 	if err != nil {
 		return fmt.Errorf("创建请求失败: %w", err)
 	}
 
 	// 模拟浏览器请求
-	req.Header.Set("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.110 Safari/537.36")
+	userAgents := []string{
+		"Mozilla/5.0 (Windows NT 10.0; Win64; x64)",
+		"AppleWebKit/537.36 (KHTML, like Gecko)",
+		"Chrome/120.0.0.0 Safari/537.36",
+	}
+	req.Header.Set("User-Agent", userAgents[time.Now().UnixNano()%int64(len(userAgents))])
 
-	resp, err := http.DefaultClient.Do(req)
+	resp, err := c.client.Do(req)
 	if err != nil {
 		return fmt.Errorf("请求失败: %w", err)
 	}