I've been porting (very simply) a Python script from Windows to Linux (directory changes mostly), and I want to add a few new features to it.
The script is used to update mods on a game server. All mods are located in ShooterGame/Content/Mods/. Some mods are included by default (TheCenter and 11111111) - every other mod is located in the same folder as the default ones, but the names consist of random numbers.
I've been trying to exclude the 2 default directories and then build a list of contents of the ShooterGame/Content/Mods/ folder, but I've failed to do so.
This is the code that I've tried to use to exclude just the TheCenter folder:
def build_list_of_mods(self):
"""
Build a list of all installed mods by grabbing all directory names from the mod folder
:return:
"""
exclude = ["TheCenter"]
if not os.path.isdir(os.path.join(self.working_dir, "ShooterGame/Content/Mods/")):
return
for curdir, dirs, files in os.walk(os.path.join(self.working_dir, "ShooterGame/Content/Mods/")):
for d in dirs:
dirs[:] = [d for d in dirs if d not in exclude]
self.installed_mods.append(d)
break
It doesn't work, sadly. Have I missed something or just done everything wrong?
Try adding topdown=True to the os.walk() function like this:
for curdir, dirs, files in os.walk(os.path.join(self.working_dir, "ShooterGame/Content/Mods/"), topdown=True):
Plus I cannot try it but maybe dirs[:] should be outside of the for-loop, as the documentation says:
When topdown is true, the caller can modify the dirnames list in-place (e.g., via del or slice assignment), and walk will only recurse into the subdirectories whose names remain in dirnames;
I'm assuming you want self.installed_mods to contain the values of dirs without the values of exclude.
You could simply call dirs.remove() with the values of exclude and then append the content of dirs to self.installed_mods.
Or in a shorter way: self.installed_mods.extend([dir for dir in dirs if dir not in exclude]).
Related
I am trying to rename several directories with the name of the first file inside them.
I am trying to:
List the files inside a folder.
Identify the directories.
For each directory, access it, grab the name of the first file inside and rename the directory with such name.
This is what I got so far but it is not working. I know the code is wrong but before fixing the code I would like to know if the logic is right. Can anyone help please?
import os
for (root, dirs, files) in os.walk('.'):
print(f'Found directory: {dirpath}')
dirlist = []
for d_idx, d in enumerate(dirlist):
print(d)
filelist = []
for f_idex, f in enumerate(filelist):
files.append(f)[1]
print(f)
os.rename(d, f)
Thank you!
There are a few problems in your code:
You are renaming directories as you iterate them with os.walk. This is not a good idea, os.walk gives you a generator, meaning it creates elements as you iterate them, so renaming things within the loop will confuse it.
Both for d_idx, d in enumerate(dirlist): and for f_idex, f in enumerate(filelist): iterate over variables that are declared to be empty lists in the line before, so those loops don't do anything. Also, within the second one, files.append(f) would append f to the list files, but the [1] at the end means "get the second element (remeber Python indexing is 0-based) of the value returned by the append function" - but append does not return anything (it modifies the list, not returns a new list), so that would fail (and you are not using the value read by [1] anyway, so it would not do anything).
In os.rename(d, f), first, since the loops before do not ever run, d and f will not have a value, but also, assuming both d and f came from dirs and files, they would be given as paths relative to their parents, not to your current directory (.), so the renaming would fail.
This code should work as you want:
import os
# List of paths to rename
renames = []
# Walk current dir
for (root, dirs, files) in os.walk('.'):
# Skip this dir (cannot rename current directory)
if root == '.': continue
# Add renaming to list
renames.append((root, files[0]))
# Iterate renaming list in reverse order so deepest dirs are renamed first
for root, new_name in reversed(renames):
# Make new full dir name (relative to current directory)
new_full_name = os.path.join(os.path.dirname(root), new_name)
# Rename
os.rename(root, new_full_name)
I need to list all files with the containing directory path inside a folder. I tried to use os.walk, which obviously would be the perfect solution.
However, it also lists hidden folders and files. I'd like my application not to list any hidden folders or files. Is there any flag you can use to make it not yield any hidden files?
Cross-platform is not really important to me, it's ok if it only works for linux (.* pattern)
No, there is no option to os.walk() that'll skip those. You'll need to do so yourself (which is easy enough):
for root, dirs, files in os.walk(path):
files = [f for f in files if not f[0] == '.']
dirs[:] = [d for d in dirs if not d[0] == '.']
# use files and dirs
Note the dirs[:] = slice assignment; os.walk recursively traverses the subdirectories listed in dirs. By replacing the elements of dirs with those that satisfy a criteria (e.g., directories whose names don't begin with .), os.walk() will not visit directories that fail to meet the criteria.
This only works if you keep the topdown keyword argument to True, from the documentation of os.walk():
When topdown is True, the caller can modify the dirnames list in-place (perhaps using del or slice assignment), and walk() will only recurse into the subdirectories whose names remain in dirnames; this can be used to prune the search, impose a specific order of visiting, or even to inform walk() about directories the caller creates or renames before it resumes walk() again.
I realize it wasn't asked in the question, but I had a similar problem where I wanted to exclude both hidden files and files beginning with __, specifically __pycache__ directories. I landed on this question because I was trying to figure out why my list comprehension was not doing what I expected. I was not modifying the list in place with dirnames[:].
I created a list of prefixes I wanted to exclude and modified the dirnames in place like so:
exclude_prefixes = ('__', '.') # exclusion prefixes
for dirpath, dirnames, filenames in os.walk(node):
# exclude all dirs starting with exclude_prefixes
dirnames[:] = [dirname
for dirname in dirnames
if not dirname.startswith(exclude_prefixes)]
My use-case was similar to that of OP, except I wanted to return a count of the total number of sub-directories inside a certain folder. In my case I wanted to omit any sub-directories named .git (as well as any folders that may be nested inside these .git folders).
In Python 3.6.7, I found that the accepted answer's approach didn't work -- it counted all .git folder and their sub-folders. Here's what did work for me:
num_local_subdir = 0
for root, dirs, files in os.walk(local_folder_path):
if '.git' in dirs:
dirs.remove('.git')
num_local_subdir += (len(dirs))
Another solution that can allow you to skip those hidden folders using any and map functions.
for root, dirs, files in os.walk(path):
if any(map(lambda p: p[0] == '.', dirs)):
continue
I need to list all files with the containing directory path inside a folder. I tried to use os.walk, which obviously would be the perfect solution.
However, it also lists hidden folders and files. I'd like my application not to list any hidden folders or files. Is there any flag you can use to make it not yield any hidden files?
Cross-platform is not really important to me, it's ok if it only works for linux (.* pattern)
No, there is no option to os.walk() that'll skip those. You'll need to do so yourself (which is easy enough):
for root, dirs, files in os.walk(path):
files = [f for f in files if not f[0] == '.']
dirs[:] = [d for d in dirs if not d[0] == '.']
# use files and dirs
Note the dirs[:] = slice assignment; os.walk recursively traverses the subdirectories listed in dirs. By replacing the elements of dirs with those that satisfy a criteria (e.g., directories whose names don't begin with .), os.walk() will not visit directories that fail to meet the criteria.
This only works if you keep the topdown keyword argument to True, from the documentation of os.walk():
When topdown is True, the caller can modify the dirnames list in-place (perhaps using del or slice assignment), and walk() will only recurse into the subdirectories whose names remain in dirnames; this can be used to prune the search, impose a specific order of visiting, or even to inform walk() about directories the caller creates or renames before it resumes walk() again.
I realize it wasn't asked in the question, but I had a similar problem where I wanted to exclude both hidden files and files beginning with __, specifically __pycache__ directories. I landed on this question because I was trying to figure out why my list comprehension was not doing what I expected. I was not modifying the list in place with dirnames[:].
I created a list of prefixes I wanted to exclude and modified the dirnames in place like so:
exclude_prefixes = ('__', '.') # exclusion prefixes
for dirpath, dirnames, filenames in os.walk(node):
# exclude all dirs starting with exclude_prefixes
dirnames[:] = [dirname
for dirname in dirnames
if not dirname.startswith(exclude_prefixes)]
My use-case was similar to that of OP, except I wanted to return a count of the total number of sub-directories inside a certain folder. In my case I wanted to omit any sub-directories named .git (as well as any folders that may be nested inside these .git folders).
In Python 3.6.7, I found that the accepted answer's approach didn't work -- it counted all .git folder and their sub-folders. Here's what did work for me:
num_local_subdir = 0
for root, dirs, files in os.walk(local_folder_path):
if '.git' in dirs:
dirs.remove('.git')
num_local_subdir += (len(dirs))
Another solution that can allow you to skip those hidden folders using any and map functions.
for root, dirs, files in os.walk(path):
if any(map(lambda p: p[0] == '.', dirs)):
continue
On a mac in python 2.7 when walking through directories using os.walk my script goes through 'apps' i.e. appname.app, since those are really just directories of themselves. Well later on in processing I am hitting errors when going through them. I don't want to go through them anyways so for my purposes it would be best just to ignore those types of 'directories'.
So this is my current solution:
for root, subdirs, files in os.walk(directory, True):
for subdir in subdirs:
if '.' in subdir:
subdirs.remove(subdir)
#do more stuff
As you can see, the second for loop will run for every iteration of subdirs, which is unnecessary since the first pass removes everything I want to remove anyways.
There must be a more efficient way to do this. Any ideas?
You can do something like this (assuming you want to ignore directories containing '.'):
subdirs[:] = [d for d in subdirs if '.' not in d]
The slice assignment (rather than just subdirs = ...) is necessary because you need to modify the same list that os.walk is using, not create a new one.
Note that your original code is incorrect because you modify the list while iterating over it, which is not allowed.
Perhaps this example from the Python docs for os.walk will be helpful. It works from the bottom up (deleting).
# Delete everything reachable from the directory named in "top",
# assuming there are no symbolic links.
# CAUTION: This is dangerous! For example, if top == '/', it
# could delete all your disk files.
import os
for root, dirs, files in os.walk(top, topdown=False):
for name in files:
os.remove(os.path.join(root, name))
for name in dirs:
os.rmdir(os.path.join(root, name))
I am a bit confused about your goal, are you trying to remove a directory subtree and are encountering errors, or are you trying to walk a tree and just trying to list simple file names (excluding directory names)?
I think all that is required is to remove the directory before iterating over it:
for root, subdirs, files in os.walk(directory, True):
if '.' in subdirs:
subdirs.remove('.')
for subdir in subdirs:
#do more stuff
I am working on a backup script in Python, and would like it to be able to ignore folders. I therefore have a list of folders to be ignored, ie ['Folder 1', 'Folder3']. I am using os.walk, and am trying to get it to skip any folder in the ignored folders list or that has any of the ignored folders as a parent directory. Has anyone done this before, as examples I've seen don't seem to work and often end up creating an empty folder?
From the docs:
When topdown is True, the caller can modify the dirnames list in-place (perhaps using del or slice assignment), and walk() will only recurse into the subdirectories whose names remain in dirnames; this can be used to prune the search, impose a specific order of visiting, or even to inform walk() about directories the caller creates or renames before it resumes walk() again.
So, iterate through your list and remove entries that match.
After the following statement
folders = [path+'/'+dir for (path,dirs,files) in os.walk(base)
for dir in dirs
if dir not in ['Folder 1', 'Folder3', ...]]
the variable folders should contain the folders you are interested in.
Edit1: ... + '/' + ... works just in Unix-like OS. I think there is a os.path.join which does the same job platform indepentently
Edit2: If you want to exclude all Subdirectories of the directories to be excluded, you can try the following:
exclusions = ['Folder 1', 'Folder3', ...]
folders = [path+'/'+dir for (path,dirs,files) in os.walk(base)
if not any([f in path for f in exclusions])
for dir in dirs
if dir not in exclusions
]