|
| 1 | +package main |
| 2 | + |
| 3 | +import ( |
| 4 | + "context" |
| 5 | + "fmt" |
| 6 | + "github.com/fsnotify/fsnotify" |
| 7 | + "github.com/pkg/errors" |
| 8 | + "github.com/shirou/gopsutil/v4/process" |
| 9 | + "golang.org/x/sync/errgroup" |
| 10 | + "io/fs" |
| 11 | + "log" |
| 12 | + "os" |
| 13 | + "os/exec" |
| 14 | + "os/signal" |
| 15 | + "path/filepath" |
| 16 | + "strconv" |
| 17 | + "strings" |
| 18 | + "sync" |
| 19 | + "syscall" |
| 20 | + "time" |
| 21 | +) |
| 22 | + |
| 23 | +// https://kubernetes.io/zh-cn/docs/tasks/configure-pod-container/share-process-namespace/ |
| 24 | +// https://cctoctofx.netlify.app/post/cloud-computing/k8s-config-update/ |
| 25 | + |
| 26 | +func main() { |
| 27 | + time.Sleep(10 * time.Second) |
| 28 | + err := NewNginxReloadWatcher().Start() |
| 29 | + if err != nil { |
| 30 | + log.Println("[ERROR] start watcher err") |
| 31 | + } |
| 32 | +} |
| 33 | + |
| 34 | +type NginxReloadWatcher struct { |
| 35 | + sync.Mutex |
| 36 | + nginxMasterPid int32 |
| 37 | + timer *time.Timer |
| 38 | + timeAfterSeconds time.Duration |
| 39 | + |
| 40 | + // file watch 的目录，用逗号分割 |
| 41 | + // 如 /etc/nginx,/etc/nginx/conf.d |
| 42 | + watchDirs []string |
| 43 | +} |
| 44 | + |
| 45 | +func NewNginxReloadWatcher() *NginxReloadWatcher { |
| 46 | + |
| 47 | + timeAfterSecondsEnv := os.Getenv("TIME_AFTER_SECONDS") |
| 48 | + var timeAfter = 30 |
| 49 | + atoi, err := strconv.Atoi(timeAfterSecondsEnv) |
| 50 | + if err == nil { |
| 51 | + timeAfter = atoi |
| 52 | + } |
| 53 | + log.Println("TIME_AFTER_SECONDS: ", timeAfter) |
| 54 | + |
| 55 | + watchDirsEnv := os.Getenv("WATCH_DIRS") |
| 56 | + |
| 57 | + log.Println("WATCH_DIRS: ", watchDirsEnv) |
| 58 | + watchDirs := strings.Split(watchDirsEnv, ",") |
| 59 | + log.Println("WATCH_DIRS after split: ", watchDirs) |
| 60 | + |
| 61 | + return &NginxReloadWatcher{ |
| 62 | + timeAfterSeconds: time.Duration(timeAfter) * time.Second, |
| 63 | + watchDirs: watchDirs, |
| 64 | + } |
| 65 | +} |
| 66 | + |
| 67 | +func (n *NginxReloadWatcher) findNginxMaterPid() (int32, error) { |
| 68 | + processes, err := process.Processes() |
| 69 | + if err != nil { |
| 70 | + return 0, err |
| 71 | + } |
| 72 | + |
| 73 | + for _, p := range processes { |
| 74 | + name, err := p.Name() |
| 75 | + if err != nil { |
| 76 | + return 0, errors.Wrap(err, "process Name err") |
| 77 | + } |
| 78 | + if name != "nginx" { |
| 79 | + continue |
| 80 | + } |
| 81 | + ppid, err := p.Ppid() |
| 82 | + if err != nil { |
| 83 | + return 0, errors.Wrap(err, "process ppid err") |
| 84 | + } |
| 85 | + if ppid == 0 { |
| 86 | + return p.Pid, nil |
| 87 | + } |
| 88 | + } |
| 89 | + return 0, errors.New("not found nginx master") |
| 90 | +} |
| 91 | + |
| 92 | +func (n *NginxReloadWatcher) Start() error { |
| 93 | + pid, err := n.findNginxMaterPid() |
| 94 | + if err != nil { |
| 95 | + return err |
| 96 | + } |
| 97 | + log.Println(fmt.Sprintf("nginx master id %d", pid)) |
| 98 | + n.nginxMasterPid = pid |
| 99 | + |
| 100 | + g, gctx := errgroup.WithContext(context.TODO()) |
| 101 | + g.Go(func() error { |
| 102 | + killSignal := make(chan os.Signal, 1) |
| 103 | + signal.Notify(killSignal, os.Interrupt, syscall.SIGTERM, os.Kill) |
| 104 | + <-killSignal |
| 105 | + return errors.New("kill signal") |
| 106 | + }) |
| 107 | + |
| 108 | + g.Go(func() error { |
| 109 | + watcher, err := fsnotify.NewWatcher() |
| 110 | + if err != nil { |
| 111 | + return err |
| 112 | + } |
| 113 | + defer watcher.Close() |
| 114 | + |
| 115 | + // Add a path. |
| 116 | + for _, parentDir := range n.watchDirs { |
| 117 | + parentDir = fmt.Sprintf("/proc/%d/root%s", pid, parentDir) |
| 118 | + err = watcher.Add(parentDir) |
| 119 | + if err != nil { |
| 120 | + return err |
| 121 | + } |
| 122 | + err = filepath.WalkDir(parentDir, func(path string, d fs.DirEntry, err error) error { |
| 123 | + if err != nil { |
| 124 | + fmt.Printf("无法访问路径 %q: %v\n", path, err) |
| 125 | + return err // 继续遍历其他文件/目录 |
| 126 | + } |
| 127 | + if d.IsDir() { |
| 128 | + watcher.Add(path) |
| 129 | + } |
| 130 | + return nil |
| 131 | + }) |
| 132 | + if err != nil { |
| 133 | + return errors.Wrap(err, "遍历目录时出错") |
| 134 | + } |
| 135 | + } |
| 136 | + |
| 137 | + watchList := watcher.WatchList() |
| 138 | + |
| 139 | + for _, item := range watchList { |
| 140 | + log.Println(item) |
| 141 | + } |
| 142 | + |
| 143 | + for { |
| 144 | + select { |
| 145 | + case <-gctx.Done(): |
| 146 | + return errors.New("gctx done") |
| 147 | + case event, ok := <-watcher.Events: |
| 148 | + if !ok { |
| 149 | + continue |
| 150 | + } |
| 151 | + log.Println("event:", event) |
| 152 | + if event.Has(fsnotify.Create) || event.Has(fsnotify.Write) || event.Has(fsnotify.Remove) || event.Has(fsnotify.Rename) || event.Has(fsnotify.Chmod) { |
| 153 | + n.timerHubSignal(event.String()) |
| 154 | + } |
| 155 | + |
| 156 | + case err, ok := <-watcher.Errors: |
| 157 | + if !ok { |
| 158 | + continue |
| 159 | + } |
| 160 | + log.Println("error:", err) |
| 161 | + } |
| 162 | + } |
| 163 | + |
| 164 | + }) |
| 165 | + return g.Wait() |
| 166 | +} |
| 167 | + |
| 168 | +func (n *NginxReloadWatcher) timerHubSignal(event string) { |
| 169 | + |
| 170 | + n.Lock() |
| 171 | + defer n.Unlock() |
| 172 | + |
| 173 | + if n.timer != nil { |
| 174 | + log.Println("[INFO] stop preview timer") |
| 175 | + n.timer.Stop() |
| 176 | + } |
| 177 | + // |
| 178 | + log.Println("[INFO] set new timer ", event) |
| 179 | + n.timer = time.AfterFunc(n.timeAfterSeconds, func() { |
| 180 | + n.Lock() |
| 181 | + defer n.Unlock() |
| 182 | + n.timer = nil |
| 183 | + |
| 184 | + command := exec.Command("/bin/bash", "-c", fmt.Sprintf("kill -HUP %d", n.nginxMasterPid)) |
| 185 | + output, err := command.CombinedOutput() |
| 186 | + s := string(output) |
| 187 | + if err != nil { |
| 188 | + log.Println(fmt.Sprintf("kill -HUP %d err, err %v, output %s, event %s", n.nginxMasterPid, err, s, event)) |
| 189 | + return |
| 190 | + } |
| 191 | + log.Println(fmt.Sprintf("kill -HUP %d success, output %s, event %s", n.nginxMasterPid, s, event)) |
| 192 | + }) |
| 193 | +} |
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