修复一个卡死问题
This commit is contained in:
+67
-2
@@ -4,6 +4,7 @@ package crawler
|
||||
|
||||
import (
|
||||
"bytes" // 字节缓冲（构造 HTTP POST 请求体）
|
||||
"context" // context 超时控制
|
||||
"encoding/json" // JSON 序列化（发送关键词数据到 harvester）
|
||||
"log" // 日志输出
|
||||
"math" // 数学运算（指数衰减、质量评分）
|
||||
@@ -28,6 +29,18 @@ type Stats struct {
|
||||
KeywordsFetched int64 // 累计提取的关键词总数
|
||||
}
|
||||
|
||||
// 熔断器状态（用 atomic int32 代替 mutex，避免持有锁时的慢 I/O）。
|
||||
const (
|
||||
circuitClosed int32 = iota // 正常：所有请求都发往 harvester
|
||||
circuitOpen // 断开：连续失败 N 次后，冷却时间内跳过所有请求
|
||||
circuitHalfOpen // 半开：冷却结束，尝试放行一次请求试探
|
||||
)
|
||||
|
||||
const (
|
||||
circuitFailureThreshold = 5 // 连续失败多少次后触发熔断
|
||||
circuitCooldownSeconds = 30 // 熔断持续时间（秒）
|
||||
)
|
||||
|
||||
// Crawler 编排整个 BFS 爬取流程。
|
||||
type Crawler struct {
|
||||
fetcher *Fetcher // HTTP 抓取器（含 robots.txt 和限流）
|
||||
@@ -35,6 +48,11 @@ type Crawler struct {
|
||||
analyzer *analyzer.Analyzer // 分词和关键词分析
|
||||
prosperMap map[string]float64 // 域名 → 反向链接繁荣值（来自 info 模块，越大越"有价值"）
|
||||
stats Stats // 原子计数器
|
||||
|
||||
// 熔断器（全用 atomic，无 mutex，无慢 I/O 时持有锁的风险）
|
||||
circuitState int32 // circuitClosed | circuitOpen | circuitHalfOpen
|
||||
circuitFailures int32 // 连续失败计数（atomic）
|
||||
circuitExpiry int64 // 熔断/半开截止 Unix 时间戳（秒）
|
||||
}
|
||||
|
||||
// New 创建一个 Crawler 实例。
|
||||
@@ -269,7 +287,32 @@ func (c *Crawler) updateSiteSuccess(host string, res *FetchResult, title, desc,
|
||||
}
|
||||
|
||||
// sendToHarvester 将关键词索引数据通过 HTTP POST 发送到收获服务器（:5000/l 端点）。
|
||||
// 熔断器基于 atomic 实现（无 mutex，不在持有锁时做慢 I/O），确保 goroutine 不会因 harvester 故障而堆积。
|
||||
func (c *Crawler) sendToHarvester(finalURL string, kws []analyzer.Keyword) {
|
||||
now := time.Now().Unix()
|
||||
|
||||
// ---- 熔断检查（atomic，无锁） ----
|
||||
state := atomic.LoadInt32(&c.circuitState)
|
||||
expiry := atomic.LoadInt64(&c.circuitExpiry)
|
||||
|
||||
switch state {
|
||||
case circuitOpen:
|
||||
if now < expiry {
|
||||
return // 熔断中，直接跳过
|
||||
}
|
||||
// 冷却结束，切换到半开，放行一个试探请求
|
||||
atomic.StoreInt32(&c.circuitState, circuitHalfOpen)
|
||||
atomic.StoreInt64(&c.circuitExpiry, now+int64(circuitCooldownSeconds))
|
||||
log.Println("[crawler] circuit: half-open, probing harvester")
|
||||
case circuitHalfOpen:
|
||||
if now < expiry {
|
||||
return // 半开冷却中，只放行第一个，其余跳过
|
||||
}
|
||||
// 半开超时，重新进入半开状态
|
||||
atomic.StoreInt32(&c.circuitState, circuitHalfOpen)
|
||||
atomic.StoreInt64(&c.circuitExpiry, now+int64(circuitCooldownSeconds))
|
||||
}
|
||||
|
||||
type payload struct {
|
||||
URL string `json:"url"`
|
||||
Keywords []analyzer.Keyword `json:"keywords"`
|
||||
@@ -279,12 +322,34 @@ func (c *Crawler) sendToHarvester(finalURL string, kws []analyzer.Keyword) {
|
||||
if err != nil {
|
||||
return
|
||||
}
|
||||
resp, err := http.Post(config.HarvesterAddr+"/l", "application/json", bytes.NewReader(data))
|
||||
|
||||
ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
|
||||
defer cancel()
|
||||
req, err := http.NewRequestWithContext(ctx, "POST", config.HarvesterAddr+"/l", bytes.NewReader(data))
|
||||
if err != nil {
|
||||
log.Printf("[crawler] harvester post failed: %v", err)
|
||||
return
|
||||
}
|
||||
req.Header.Set("Content-Type", "application/json")
|
||||
|
||||
// ---- HTTP 请求（此时没有任何锁） ----
|
||||
resp, err := http.DefaultClient.Do(req)
|
||||
|
||||
// ---- 结果处理（atomic，无锁） ----
|
||||
if err != nil {
|
||||
failures := atomic.AddInt32(&c.circuitFailures, 1)
|
||||
if failures >= circuitFailureThreshold {
|
||||
atomic.StoreInt32(&c.circuitState, circuitOpen)
|
||||
atomic.StoreInt64(&c.circuitExpiry, now+int64(circuitCooldownSeconds))
|
||||
log.Printf("[crawler] circuit OPEN: harvester unreachable (%d failures), cooling for %ds",
|
||||
failures, circuitCooldownSeconds)
|
||||
}
|
||||
return
|
||||
}
|
||||
resp.Body.Close()
|
||||
|
||||
// ---- 成功：重置熔断器 ----
|
||||
atomic.StoreInt32(&c.circuitFailures, 0)
|
||||
atomic.StoreInt32(&c.circuitState, circuitClosed)
|
||||
}
|
||||
|
||||
// schedule 从候选 URL 集合中选出下一轮 BFS 队列。
|
||||
|
||||
@@ -11,6 +11,7 @@ import (
|
||||
"net/url" // URL 解析
|
||||
"regexp" // 正则表达式（site: 过滤语法）
|
||||
"sort" // 排序
|
||||
"strconv" // 字符串转整数
|
||||
"strings" // 字符串操作
|
||||
"sync" // 互斥锁（保护并发切片写入）
|
||||
"time" // 时间戳
|
||||
@@ -46,6 +47,8 @@ func New(db *storage.DB, infoSvc *info.Service, a *analyzer.Analyzer) *Server {
|
||||
func (s *Server) Handler() http.Handler {
|
||||
mux := http.NewServeMux()
|
||||
mux.HandleFunc("/search", s.handleSearch)
|
||||
mux.HandleFunc("/admin/recent", s.handleAdminRecent)
|
||||
mux.HandleFunc("/admin/stats", s.handleAdminStats)
|
||||
return mux
|
||||
}
|
||||
|
||||
@@ -55,6 +58,149 @@ func (s *Server) ListenAndServe(addr string) error {
|
||||
return http.ListenAndServe(addr, s.Handler())
|
||||
}
|
||||
|
||||
// ---- Admin 接口 ----
|
||||
|
||||
// recentItem 是 /admin/recent 接口返回的单条记录。
|
||||
type recentItem struct {
|
||||
URL string `json:"url"`
|
||||
Title string `json:"title"`
|
||||
Description string `json:"description"`
|
||||
Domain string `json:"domain"`
|
||||
Language map[string]float64 `json:"language"`
|
||||
WordCount int `json:"word_count"`
|
||||
CrawledAt int64 `json:"crawled_at"`
|
||||
}
|
||||
|
||||
// handleAdminRecent 返回最近爬取的条目列表，按爬取时间倒序。
|
||||
// 参数：limit（默认50，最大200）。
|
||||
func (s *Server) handleAdminRecent(w http.ResponseWriter, r *http.Request) {
|
||||
w.Header().Set("Access-Control-Allow-Origin", "*")
|
||||
w.Header().Set("Content-Type", "application/json; charset=utf-8")
|
||||
|
||||
limit := 50
|
||||
if l := r.URL.Query().Get("limit"); l != "" {
|
||||
if v, err := strconv.Atoi(l); err == nil && v > 0 {
|
||||
limit = v
|
||||
}
|
||||
}
|
||||
if limit > 200 {
|
||||
limit = 200
|
||||
}
|
||||
|
||||
type entry struct {
|
||||
url string
|
||||
snippet *storage.SnippetEntry
|
||||
siteInfo *storage.SiteInfo
|
||||
}
|
||||
|
||||
var items []entry
|
||||
s.db.ForEachSnippet(func(url string, snippet *storage.SnippetEntry) error {
|
||||
siteInfo, _ := s.db.GetSiteInfo(netloc(url))
|
||||
items = append(items, entry{url, snippet, siteInfo})
|
||||
return nil
|
||||
})
|
||||
|
||||
// 按时间倒序
|
||||
sort.Slice(items, func(i, j int) bool {
|
||||
return items[i].snippet.Timestamp > items[j].snippet.Timestamp
|
||||
})
|
||||
|
||||
if len(items) > limit {
|
||||
items = items[:limit]
|
||||
}
|
||||
|
||||
result := make([]recentItem, 0, len(items))
|
||||
for _, e := range items {
|
||||
lang := e.siteInfo.Languages
|
||||
if lang == nil {
|
||||
lang = make(map[string]float64)
|
||||
}
|
||||
desc := e.snippet.Description
|
||||
if len(desc) > 200 {
|
||||
desc = desc[:200]
|
||||
}
|
||||
result = append(result, recentItem{
|
||||
URL: e.url,
|
||||
Title: e.snippet.Title,
|
||||
Description: desc,
|
||||
Domain: netloc(e.url),
|
||||
Language: lang,
|
||||
WordCount: len(e.snippet.Text),
|
||||
CrawledAt: e.snippet.Timestamp,
|
||||
})
|
||||
}
|
||||
|
||||
resp := map[string]any{
|
||||
"items": result,
|
||||
"total": len(items),
|
||||
}
|
||||
json.NewEncoder(w).Encode(resp)
|
||||
}
|
||||
|
||||
// handleAdminStats 返回全局统计：域名分布、语种分布、总 URL 数、总词数。
|
||||
func (s *Server) handleAdminStats(w http.ResponseWriter, r *http.Request) {
|
||||
w.Header().Set("Access-Control-Allow-Origin", "*")
|
||||
w.Header().Set("Content-Type", "application/json; charset=utf-8")
|
||||
|
||||
domainCount := make(map[string]int)
|
||||
langCount := make(map[string]int)
|
||||
totalWords := 0
|
||||
total := 0
|
||||
|
||||
s.db.ForEachSnippet(func(url string, snippet *storage.SnippetEntry) error {
|
||||
total++
|
||||
domain := netloc(url)
|
||||
domainCount[domain]++
|
||||
totalWords += len(snippet.Text)
|
||||
|
||||
siteInfo, _ := s.db.GetSiteInfo(domain)
|
||||
if siteInfo != nil {
|
||||
for lang, ratio := range siteInfo.Languages {
|
||||
if ratio > 0.1 {
|
||||
langCount[lang]++
|
||||
}
|
||||
}
|
||||
}
|
||||
return nil
|
||||
})
|
||||
|
||||
// 排序取 Top
|
||||
type kv struct{ k string; v int }
|
||||
topDomains := make([]kv, 0, len(domainCount))
|
||||
for k, v := range domainCount {
|
||||
topDomains = append(topDomains, kv{k, v})
|
||||
}
|
||||
sort.Slice(topDomains, func(i, j int) bool { return topDomains[i].v > topDomains[j].v })
|
||||
if len(topDomains) > 20 {
|
||||
topDomains = topDomains[:20]
|
||||
}
|
||||
topLangs := make([]kv, 0, len(langCount))
|
||||
for k, v := range langCount {
|
||||
topLangs = append(topLangs, kv{k, v})
|
||||
}
|
||||
sort.Slice(topLangs, func(i, j int) bool { return topLangs[i].v > topLangs[j].v })
|
||||
if len(topLangs) > 10 {
|
||||
topLangs = topLangs[:10]
|
||||
}
|
||||
|
||||
domainsMap := make(map[string]int)
|
||||
for _, kv := range topDomains {
|
||||
domainsMap[kv.k] = kv.v
|
||||
}
|
||||
langsMap := make(map[string]int)
|
||||
for _, kv := range topLangs {
|
||||
langsMap[kv.k] = kv.v
|
||||
}
|
||||
|
||||
resp := map[string]any{
|
||||
"total_urls": total,
|
||||
"total_words": totalWords,
|
||||
"domains": domainsMap,
|
||||
"languages": langsMap,
|
||||
}
|
||||
json.NewEncoder(w).Encode(resp)
|
||||
}
|
||||
|
||||
// ---- 搜索处理器 ----
|
||||
|
||||
// searchResponse 是搜索 API 的 JSON 响应结构。
|
||||
|
||||
@@ -315,3 +315,16 @@ func (d *DB) ForEachSite(fn func(host string, info *SiteInfo) error) error {
|
||||
})
|
||||
})
|
||||
}
|
||||
|
||||
// ForEachSnippet 遍历所有 URL 摘要条目，对每个条目调用 fn。
|
||||
func (d *DB) ForEachSnippet(fn func(url string, entry *SnippetEntry) error) error {
|
||||
return d.db.View(func(tx *bolt.Tx) error {
|
||||
return tx.Bucket(bucketGate).ForEach(func(k, v []byte) error {
|
||||
var entry SnippetEntry
|
||||
if err := decompressUnmarshal(v, &entry); err != nil {
|
||||
return nil // 跳过损坏条目
|
||||
}
|
||||
return fn(string(k), &entry)
|
||||
})
|
||||
})
|
||||
}
|
||||
|
||||
Reference in New Issue
Block a user