Use glob to iterate through files in dir to select correct extension? - python-3.x

Question

I'm trying to iterate through a dir a select the first file available.
These files look like this:
img_1.png img_2.png img_3.mp4 img_4.png img_5.jpg img_6.mp4
As you can see their names are cohesive but their extensions are different. I'd like the script to iterate through each extension for each number before it moves onto the next, IE:
I assume the best way to go about it is iterating through each file and extention like this: img_1.png img_1.jpg and img_1.mp4, and if neither of the three are available, move to the next file and repeat like img_2.png img_2.jpg and img_2.mp4 until there is an available
Question:
Is it best to iterate through the files and use glob to extend a file path with the extensions? Is there a better method?
This is what I thought would work, but it doesn't:
# Gets number of files in dir
list = os.listdir(folder_path)
number_files = len(list)
# Chooses file from dir
e = 0
for i in range(number_files):
try:
chosen_file = folder_path + "img_" + str(e)
for ext in ('*.jpg', '*.png', '*.mp4'):
full_path = chosen_file.extend(glob(join(chosen_file, ext)))
print (full_path)
#random_file = random.choice(os.listdir(folder_path)) # Chooses random file
except:
e += 1
print ('Hit except')

Answer 1

Are there other files in the folder with different names that you do not want to select or are all the files in the folder of interest? Is all that matters that they have the those 3 extensions or are the names important as well?
If you are only interested in files with those 3 extensions then this code will work
import os
import glob
folder_path = 'test\\'
e = 0
for r,d,f in os.walk(folder_path):
for file in f:
extensions = ['.jpg', '.png', '.mp4']
for ext in extensions:
if file.endswith(ext):
full_path = os.path.join(folder_path, file)
print (full_path)
else:
e += 1
print ('Hit except')

Answer 2

Given:
$ ls /tmp
img_1.png img_1.jpg img_2.png img_4.png img_5.jpg img_3.mp4 img_6.mp4
You can use pathlib and a more targeted glob:
from pathlib import Path
p=Path('/tmp')
for fn in (x for x in p.glob('img_[0-9].*')
if x.suffix in ('.png', '.jpg', '.mp4')):
print(fn)
Prints:
/tmp/img_1.png
/tmp/img_1.jpg
/tmp/img_2.png
/tmp/img_4.png
/tmp/img_5.jpg
/tmp/img_3.mp4
/tmp/img_6.mp4

Answer 3

Answer:
Decided to not use glob and did this instead:
i = 0
for i in range(number_files):
try:
chosen_file = folder_path + "img_" + str(i)
jpg_file = chosen_file + ".jpg"
png_file = chosen_file + ".png"
mp4_file = chosen_file + ".mp4"
if os.path.exists(png_file) == True:
print ('png true')
print (png_file)
break
elif os.path.exists(jpg_file) == True:
print ('jpg true')
print (jpg_file)
break
elif os.path.exists(mp4_file) == True:
print ('mp4 true')
print (mp4_file)
break
except:
i += 1
print ('false')