Let's break down why your code is throwing that FileNotFoundError and fix it step by step:

Root Causes of the Error #

1. Malformed Command String: Your concatenation of command parts is missing spaces, creating an invalid string like libreoffice --headless --convert-totxt:Text (encoded):UTF8test.doc. Subprocess tries to execute this entire string as a single non-existent executable, hence the error.
2. Incorrect Subprocess Usage: Passing a single string to subprocess.call() without shell=True tells Python to look for an executable with that full string as its name—this isn’t what you want. Using a list of arguments is safer and avoids this issue.
3. Hardcoded Filename: You’re using test.doc instead of the actual uploaded filename, so even if the command worked, it wouldn’t target the right file.
4. Relative Path Issue: Using media/ as the path might fail because LibreOffice may not run in the same working directory as your Django app.

Corrected Code #

Here's the fixed API view with proper error handling and correct subprocess usage:

import os
import subprocess
from rest_framework.decorators import api_view
from rest_framework.response import Response
from rest_framework import status
from django.core.files.storage import FileSystemStorage

@api_view(['POST'])
def convertfiledoc(request):
    try:
        # Retrieve uploaded file from request
        file = request.FILES['file']
        fs = FileSystemStorage()
        
        # Save file to media directory and get its filename
        filename = fs.save(file.name, file)
        # Get full absolute path to the uploaded file
        full_file_path = fs.path(filename)
        
        # Build LibreOffice command as a list of arguments (safer than shell=True)
        cmd = [
            'libreoffice',
            '--headless',
            '--convert-to',
            'txt:Text (encoded):UTF8',
            full_file_path
        ]
        
        # Execute conversion command
        exit_code = subprocess.call(cmd)
        
        if exit_code == 0:
            # Generate converted TXT filename
            txt_filename = os.path.splitext(filename)[0] + '.txt'
            # Get URL to access the converted file
            txt_file_url = fs.url(txt_filename)
            return Response(
                data={"message": "Conversion successful", "txt_file_url": txt_file_url},
                status=status.HTTP_200_OK
            )
        else:
            return Response(
                data={"message": f"Conversion failed with exit code {exit_code}"},
                status=status.HTTP_500_INTERNAL_SERVER_ERROR
            )
    
    # Handle missing file in request
    except KeyError:
        return Response(
            data={"message": "Please upload a file using the 'file' key"},
            status=status.HTTP_400_BAD_REQUEST
        )
    
    # Catch unexpected errors
    except Exception as e:
        return Response(
            data={"message": f"An error occurred: {str(e)}"},
            status=status.HTTP_500_INTERNAL_SERVER_ERROR
        )

Additional Checks to Ensure Success #

• Install Required LibreOffice Packages:
  On your Ubuntu 18.04 server, run these commands to get headless support and DOC file handling:

  sudo apt update
  sudo apt install libreoffice-headless libreoffice-writer
  

• Verify LibreOffice Path:
  If you still get a "not found" error, run which libreoffice to get the absolute path (usually /usr/bin/libreoffice) and replace 'libreoffice' in the cmd list with this full path.
• Check Permissions:
  Ensure the user running your Django server (e.g., www-data for Apache) has read/write access to the media directory.
• Validate File Types:
  Add a check to confirm the uploaded file is a DOC/DOCX file before processing to avoid unnecessary errors.

内容的提问来源于stack exchange，提问作者johnny68