运行 watcher fsinotify 以观察配置文件的变化 | GO

Question

我正在尝试使用 fsinotfiy lib 在 go 中运行观察程序以跟踪配置 json 文件更改 - 使用此代码

func waitForChangeEventLoop(w *fsnotify.Watcher) (error) {
    for {
        select {
        // Read from Errors.
        case _, ok := <-w.Errors:
            if !ok { 
                // Channel was closed (i.e. Watcher.Close() was called).
                return nil
            }
        // Read from Events.
        case e, ok := <-w.Events:
            if !ok { 
                // Channel was closed (i.e. Watcher.Close() was called).
                return nil
            }

            if e.Has(fsnotify.Write) {
                fmt.Println("Something happen")
            }
        }
    }

    return nil
}

func setFileWatcher() (error) {
    w, err := fsnotify.NewWatcher()
    if err != nil {
        return err
    }

    go waitForChangeEventLoop(w)

    err = w.Add(gConfiguredCollectorsPath)
    if err != nil {
        return err
    }

    defer w.Close()

    return nil
}

我希望在进程运行期间得到注释，每当我更改 json 文件时

Answer 1

这样的事情应该有效。 只是为了保持简单而在 main 中这样做，但像您一样以单独的方法离开也应该有效。

package main

import (
    "log"

    "github.com/fsnotify/fsnotify"
)

func main() {
    // Creating a new watcher
    watcher, err := fsnotify.NewWatcher()
    if err != nil {
        log.Fatalf("Failed to create watcher: %v", err)
    }

    //Defer close the watcher
    defer watcher.Close()

    // Adding some sample config file
    err = watcher.Add("config.json")
    if err != nil {
        log.Fatalf("Failed to add file to watcher: %v", err)
    }

    // Let's start the event loop
    for {
        select {
        case event := <-watcher.Events:
            // Checks for any modification in config file
            if event.Op&fsnotify.Write == fsnotify.Write {
                log.Println("Configuration file changed, reloading...")
                
            }
        case err := <-watcher.Errors:
            log.Printf("Watcher error: %v", err)
        }
    }
}