importing module from second module

Question

I am developing small app with few submodules:

src/
    setup.py
    myapp/
        myGuiapp.py
        modules/
            __init__.py
            editorGui.py
            fileParser.py

modules/__ init __.py

from editorGui import editorWindow
from fileParser import parseMyFile

myGuiapp.py

from modules import editorWindow
from modules import parseMyFile
parseMyFile(parms)
editorWindow(self)

EditorGui.py

from fileParser import parseMyFile
# from .fileParser import parseMyFile
# from modules.fileParser import parseMyFile
fileParser(parms)

I would like to have my EditorGui.py to be called from myGuiapp.py but also to be able to run it by itself. How should i setup relative importing in such case ?

If in EditorGui.py I will set :

from modules.fileParser import parseMyFile
>python editorGui.py
ModuleNotFoundError: No module named 'modules'

but from main app

>python myGuiapp.py

OK !

If in EditorGui.py I will set :

from .fileParser import parseMyFile
>python EditorGui.py
ModuleNotFoundError: No module named '__main__.fileParser'; '__main__' is not a package

If in EditorGui.py I will set :

from fileParser import parseMyFile
>python editorGui.py

OK !

>python myGuiapp.py
ModuleNotFoundError: No module named 'fileParser'

How can I make both work and what i am doing wrong here? I would like to avoid setting up ABSOLETE paths to this dev directory. What would be most pythonic and clean way to structure such app ?

EDIT: After @Diego Trazzi post, I've decided to move my EditorGui.py up the level:

src/
    setup.py
    myapp/
        myGuiapp.py
        editorGui.py
        modules/
            __init__.py
            fileParser.py

This solves many issues but for curiosity, my question still stands. How can I import module from same level while being imported by code from parent directory?

Answer 1

To avoid specifying the relative path to the modules You could append to your file the path:

# yourfile.py
import sys
sys.path.insert(0, '/path/to/application/app/folder')

You could also specify it in the shell from which you run the command:

python [-bBdEiOQsRStuUvVWxX3?] [-c command | -m module-name | script | - ] [args]

https://docs.python.org/2/using/cmdline.html

Better solution

Ideally your project should be structured in such way so all the

package_name/
  /* setup.py and other misc files */
  package_name/
    __init__.py
    /* module files go here */
  test/
    /* tests go here */

So that your executables reside in the top level and when you distribute your project users will not have to dig into sub folders. I have found this answer very helpful:

Python Nesting Modules