如何阻止PyInstaller生成的临时文件被自动删除？

Hey there, dealing with a 10GB reload every time your Flask app starts must be frustrating—let's fix that. Here are the most practical solutions depending on your needs:

1. Switch to --onedir Mode (Best for Large Apps) #

The root issue here is that you're using PyInstaller's --onefile mode, which automatically extracts all your app's files to a temporary _MEIPASS folder and deletes it on exit. Instead, use the directory mode which skips the temporary extraction entirely:

• Run this command to build your app:

  pyinstaller --onedir your_flask_app.py
  

• Once built, all your app's files will live in the dist/your_flask_app directory. You just need to run the executable inside that folder directly.
• Pros: No more repeated extraction—starts instantly, no temp file cleanup to worry about.
• Cons: You'll have to distribute the entire directory instead of a single EXE file.

2. Use a Fixed Custom Temp Directory (If You Need --onefile Mode) #

If you must keep the single EXE distribution, you can force PyInstaller to use a permanent custom directory instead of the system's temporary folder. This way, the files stay intact between sessions:

Step 1: Specify a Custom Runtime Temp Directory #

Build your app with the --runtime-tmpdir flag to point to a fixed location:

pyinstaller --onefile --runtime-tmpdir "C:/FlaskAppTemp" your_flask_app.py

(Replace the path with one that makes sense for your OS—e.g., ~/FlaskAppTemp on Linux/macOS)

Step 2: Prevent PyInstaller From Deleting the Directory #

By default, PyInstaller still deletes the temp folder on exit. To stop this, tweak your app's code to intercept the cleanup process:

• Add this snippet early in your Flask app (before any other imports that rely on _MEIPASS):

  import sys
  import os
  import atexit
  
  # Check if we're running from a PyInstaller onefile build
  if hasattr(sys, '_MEIPASS'):
      # Remove PyInstaller's default temp folder cleanup handler
      for handler in atexit._exithandlers:
          if handler[0].__name__ == '_cleanup':
              atexit.unregister(handler[0])
              break
  

• Note: Add occasional manual cleanup logic for old temp files later—otherwise the directory will grow as you update your app.

3. Bonus: Optimize Bundle Size (Optional) #

While this doesn't stop temp file deletion, trimming your bundle size will speed up initial loads if you stick with --onefile:

• Exclude unnecessary modules with --exclude-module:

  pyinstaller --onefile --exclude-module tkinter --exclude-module pandas your_flask_app.py
  

• Use UPX compression (install UPX first) with the --upx-dir flag:

  pyinstaller --onefile --upx-dir /path/to/upx your_flask_app.py
  

内容的提问来源于stack exchange，提问作者Ugurcan