Using inspect.getsourcelines() for a module that is not stored in the same folder

Question

I have a module stored in some specific local location on which I am performing dynamic import using, importlib in python. After importing the module I am using file.readlines() to read all the lines in the file. If the file has a function called foo I want to get the source code of the function.

The program I am using, I have written below. When I use this program, I am getting error NameError: name 'file_name' is not defined

Note: I have separated file name from the location and hence I have written the file_name directly as a variable below.

spec = importlib.util.spec_from_file_location(file_name, file_location)
load_module = importlib.util.module_from_spec(spec)

with open(file_abs_location, "r") as file:
    lines = file.readlines()
    for line in lines:
        if line.startswith("def foo"):
            line = line.replace("def ", "").replace("():", "")
            _name = file_name.replace("py", "")
            final_string = _name+line
            print(final_string)
            function_lines = inspect.getsourcelines(eval(final_string))

And I know that I am already reading the lines of the file and I can get function content from there but the problem is that I have to run this for many files and each file has different number of rows in foo function. So I cannot read a definite amount of lines after a function name.

Considering all my constraints, can someone please guide me on how to do this?

Sorry I think I'm missing something, is your problem that you are getting the `NameError` or something else? — tomjn, Feb 07 '23 at 14:27
My problem is simple. If I have a module which is in some other location, how do I get function inside this module using inspect.getsourcelines()? — programmer_04_03, Feb 07 '23 at 14:58

tomjn · Accepted Answer · 2023-02-07T15:41:14.463

1

I'm not 100% sure what your aim is but I think you are making it a bit more complicated than it needs to be. You can use getattr on the module to find out if that function exists and if it does then get the function lines.

Here is an example to get the lines of the merge function in pandas (the superfulous use of importlib is just to more closely match the question above)

import importlib, inspect
load_module = importlib.import_module("pandas")
if func := getattr(load_module, "merge", None):
    function_lines = inspect.getsourcelines(func)

edited Feb 07 '23 at 15:41

answered Feb 07 '23 at 15:25

tomjn

5,100
1
9
24

Hello, I tried the method above. It given me an error ```module 'function_file' has no attribute 'foo'``` I know this means that the module has no function with the specified name. But, I know for a fact that this is not true. Is it because the way in which I am importing the module? Or is there any other explanation for this behavior? I am importing the module in the way I have shown because the module has special extension which behaves like a python file but is not a .py file. – programmer_04_03 Feb 08 '23 at 09:05
I had to play around a bit with the program given in the explanation for importing the module dynamically using importlib. But, the overall logic I used is just like the one explained in the answer. Thanks for answering the question. – programmer_04_03 Feb 08 '23 at 13:21

Using inspect.getsourcelines() for a module that is not stored in the same folder

1 Answers1