cron-job.go

package main

import (
    "fmt"
    "log"
    "os"
    "path/filepath"
    "time"
)

const folderPath = "/path/to/folder"
const logPath = "/path/to/log/file.log"

func main() {
    // create log file if not exists
    _, err := os.Stat(logPath)
    if os.IsNotExist(err) {
        _, err := os.Create(logPath)
        if err != nil {
            log.Fatalf("Failed to create log file: %v", err)
        }
    }

    // start file system monitor
    go monitorFileSystem()

    // start cron job
    go processFiles()

    // keep main thread running
    select {}
}

func monitorFileSystem() {
    for {
        err := filepath.Walk(folderPath, func(path string, info os.FileInfo, err error) error {
            if err != nil {
                return err
            }
            if !info.IsDir() {
                // log path of added file
                log.Printf("Added file: %s\n", path)

                // append path to log file
                f, err := os.OpenFile(logPath, os.O_APPEND|os.O_WRONLY, 0644)
                if err != nil {
                    log.Fatalf("Failed to open log file: %v", err)
                }
                defer f.Close()
                _, err = fmt.Fprintln(f, path)
                if err != nil {
                    log.Fatalf("Failed to write to log file: %v", err)
                }
            }
            return nil
        })
        if err != nil {
            log.Fatalf("Failed to monitor file system: %v", err)
        }
        time.Sleep(time.Second)
    }
}

func processFiles() {
    // wait until midnight
    now := time.Now()
    nextMidnight := now.Truncate(24 * time.Hour).AddDate(0, 0, 1)
    time.Sleep(nextMidnight.Sub(now))

    // read log file and process each file
    f, err := os.Open(logPath)
    if err != nil {
        log.Fatalf("Failed to open log file: %v", err)
    }
    defer f.Close()
    scanner := bufio.NewScanner(f)
    for scanner.Scan() {
        path := scanner.Text()
        // process file in a goroutine
        go func(path string) {
            // TODO: process file
        }(path)
    }
    if err := scanner.Err(); err != nil {
        log.Fatalf("Failed to read log file: %v", err)
    }

    // wait for next midnight and repeat
    for {
        now := time.Now()
        nextMidnight := now.Truncate(24 * time.Hour).AddDate(0, 0, 1)
        time.Sleep(nextMidnight.Sub(now))
        // read log file and process each file
        f, err := os.Open(logPath)
        if err != nil {
            log.Fatalf("Failed to open log file: %v", err)
        }
        defer f.Close()
        scanner := bufio.NewScanner(f)
        for scanner.Scan() {
            path := scanner.Text()
            // process file in a goroutine
            go func(path string) {
                // TODO: process file
            }(path)
        }
        if err := scanner.Err(); err != nil {
            log.Fatalf("Failed to read log file: %v", err)
        }
    }
}