Monitora a pasta e executa o comando se houver um arquivo lá?

Question

Eu gostaria de ter meu monitor do Ubuntu Folder A . Se houver um arquivo .sh , gostaria de mover esse arquivo para Folder B e executá-lo em segundo plano. Isso é possível? O que devo usar para que isso aconteça?

    

Answer 1

Você tem algumas opções:

1. Usando inotifywait

#!/bin/bash
# set path to watch
DIR="/path/to/sourcedir"
# set path to copy the script to
target_dir="/path/to/targetdir"

inotifywait -m -r -e moved_to -e create "$DIR" --format "%f" | while read f

do
    echo $f
    # check if the file is a .sh file
    if [[ $f = *.sh ]]; then
      # if so, copy the file to the target dir
      mv "$DIR/$f" "$target_dir"
      # and rum it
      /bin/bash "$target_dir/$f" &
    fi
done

Explicação sobre inotifywait

Definir opções

Para logar continuamente, você precisa definir a opção -m :

de man inotifywait :

-m, --monitor
    Instead of exiting after receiving a single event, execute indefinitely. The default behaviour is to exit after the first event occurs. 

Para registrar recursivamente, você precisa definir a opção -r :

-r, --recursive
    Watch all subdirectories of any directories passed as arguments. Watches will be set up recursively to an unlimited depth. Symbolic links are not traversed. Newly created subdirectories will also be watched. 

Se você não precisar de monitoramento recursivo, remova a opção.

Eventos

Além disso, você precisa especificar evento (s) para acionar:

EVENTS
       The following events are valid for use with the -e option:

       access A  watched  file  or  a file within a watched directory was read
              from.

       modify A watched file or a file within a watched directory was  written
              to.

       attrib The metadata of a watched file or a file within a watched direc‐
              tory was modified.  This includes timestamps, file  permissions,
              extended attributes etc.

       close_write
              A  watched file or a file within a watched directory was closed,
              after being opened in writeable mode.  This does not necessarily
              imply the file was written to.

       close_nowrite
              A  watched file or a file within a watched directory was closed,
              after being opened in read-only mode.

       close  A watched file or a file within a watched directory was  closed,
              regardless  of  how  it  was opened.  Note that this is actually
              implemented  simply  by  listening  for  both  close_write   and
              close_nowrite, hence all close events received will be output as
              one of these, not CLOSE.

       open   A watched file or a file within a watched directory was opened.

       moved_to
              A file or directory was moved into a  watched  directory.   This
              event  occurs  even  if the file is simply moved from and to the
              same directory.

       moved_from
              A file or directory was moved from a  watched  directory.   This
              event  occurs  even  if the file is simply moved from and to the
              same directory.

       move   A file or directory was moved from or to  a  watched  directory.
              Note  that  this is actually implemented simply by listening for
              both moved_to and moved_from, hence all  close  events  received
              will be output as one or both of these, not MOVE.

       move_self
              A  watched  file  or  directory was moved. After this event, the
              file or directory is no longer being watched.

       create A file or directory was created within a watched directory.

       delete A file or directory within a watched directory was deleted.

       delete_self
              A watched file or directory was deleted.  After this  event  the
              file  or  directory  is no longer being watched.  Note that this
              event can occur even if it is not explicitly being listened for.

       unmount
              The filesystem on which a watched file or directory resides  was
              unmounted.   After this event the file or directory is no longer
              being watched.  Note that this event can occur even if it is not
              explicitly being listened to.

Você precisa preceder cada um dos seus eventos, para ser acionado, com -e :

-e moved_to -e create

É claro que você pode definir qualquer acionador de evento na lista.

Com a opção --format "%f" , fazemos com que o comando imprima o arquivo nome , que usaremos para copiar e executar o arquivo, combinado com os caminhos definidos.

Como usar

1. Instale o inotify-tools

   sudo apt-get install intotify-tools
   

2. Copie o script em um arquivo vazio, salve-o como watch_dir.sh

3. Na cabeça do script, defina o diretório a ser assistido e copie os scripts para
4. Execute-o e ele começa a ver seu diretório.

2. Usando python

Sem instalar nada extra, podemos fazer o mesmo, no entanto, com um pequeno script python:

#!/usr/bin/env python3
import subprocess
import os
import time
import shutil

source = "/path/to/sourcedir"
target = "/path/to/targetedir"
files1 = os.listdir(source)

while True:
    time.sleep(2)
    files2 = os.listdir(source)
    # see if there are new files added
    new = [f for f in files2 if all([not f in files1, f.endswith(".sh")])]
    # if so:
    for f in new:
        # combine paths and file
        trg = os.path.join(target, f)
        # copy the file to target
        shutil.move(os.path.join(source, f), trg)
        # and run it
        subprocess.Popen(["/bin/bash", trg])
        print(trg)
    files1 = files2

Como usar

1. Copie o script em um arquivo vazio, salve-o como watch_dir.py
2. Na cabeça do script, defina o diretório a ser observado e copie os scripts para ( source, target )
3. Execute-o e ele começa a ver seu diretório.

Nota

Ambas as opções acima assumem que os scripts não precisam de argumentos, mas esse é obviamente o caso em uma configuração como essa.