I have a powershell script, that downloads all files form an S3 bucket, and then removes the files from the bucket. All the files I'm removing are stored in a subfolder in the S3 bucket, and I just want to delete the files but maintain the subfolders.
I'm currently using the following command to delete the files in S3 once the file has been downloaded from S3.
Remove-S3Object -BucketName $S3Bucket -Key $key -Force
My problem is that if it removes all the files in the subfolder, the subfolder is removed as well. Is there a way to remove the file, but keep the subfolder present using powerhsell. I believe I can do something like this,
aws s3 rm s3://<key_to_be_removed> --exclude "<subfolder_key>"
but not quite sure if that'll work.
I'm looking for the best way to accomplish this, and at the moment, my only option is to recreate the subfolder via the script if the subfolder not longer exists.
The only way to accomplish having an empty folder is to create a zero-length object which has the same name as the folder you want to keep. This is actually how the S3 console enables you to create an empty folder.
You can check this by running $ aws s3 ls s3://your-bucket/folderfoo/ and observing an output object having length of zero bytes.
See more on this topic here.
As already commented, S3 does not really have folders the way file systems do. The folders as presented by most S3 browsers are just generated based on the paths of the files/objects. If you upload an object/file named folder/file, the browsers will present folder as folder with file as a file in the folder. But technically, all that there is is the file/object folder/file. The folder does not exist on its own.
You can explicitly create a folder by creating an empty empty-named object with "in the folder": folder/. If you do that, it will appear the the folder exists even if there are no files in it. But if you do not do that, the virtual folder disappears once you remove all objects in the folder.
Now the question is whether your command removes even the empty named object representing the folder or not. I cannot tell that.
Related
So, I have the following structure on S3:
mainbucket
DataFeeds/
Statement/
We had incidents where the DataFeeds/ folder was being deleted! So, I tested with following:
aws s3api put-object --bucket mainbucket --key DataFeeds/.donotdelete
But, if I execute this (deleting blah.txt even if it does not exists) the DataFeeds/ folder gets deleted too:
aws s3 rm s3://mainbucket/DataFeeds/blah.txt
So, how do we prevent a folder from being deleted on S3?
Versions used:
aws-cli/2.2.46 Python/3.9.7 Darwin/20.6.0 source/x86_64 prompt/off
Folders do not exist in Amazon S3. It is a 'flat' storage service where the Key (filename) of an object includes the full path, including directories.
Amazon S3 will 'simulate' folders for you. For example, if you upload a file to invoices/january.txt, then the invoices directory will 'magically' appear. If you then delete that object, the directory will then 'disappear'. This is because it never actually existed.
If you use the Create folder button in the S3 management console, it will create a zero-length object with the same name as the directory. This will 'force' the directory to appear in the bucket listing. Deleting the zero-length object will cause the directory to disappear if there are no objects with that same Prefix (path).
The best advice for using S3 is to pretend that folders exist. You can place an object in any path and the (pretend) directories will magically appear. Do not worry about directories disappearing, since they never actually existed!
If you really need empty directories to stay around, use that Create folder button to create the zero-length object. It will stay around until you delete the zero-length object.
We want to delete temp files from the S3 bucket from one of the folder on daily basis. I have tried with s3 lifecycle policy. For example my folder name is Test, I have set prefix for expiration is Test/ . But the issue here is along with all the files, Test folder is also getting deleted. I want to keep the folder as is and only delete the files in that . Is there any way i can do this?
Don't worry about the folder.
As soon as you have at least one file "in" the folder (object key beginning with Test/) it will appear again and when there are no objects beginning with that key prefix it will disappear -- all of this is normal/expected behavior because folders in S3 are not containers like they are on a filesystem and they do not actually need to exist before putting files "in" them.
After deleting a few folders in our S3 bucket, I am not able to see any of my folders through the web console. We had around 10 folders and ended up deleting 6 of them. The remaining four show up when I do an 'ls' on that S3 bucket through the CLI but the bucket shows up empty on the web console.
When I turn on 'Versions' I see everything (including the 6 folders that were deleted). Am I overlooking something extremely simple?
Folders do not actually exist in Amazon S3.
For example, you could create an object like this:
aws s3 cp foo.txt s3://my-bucket/folder1/folder2/foo.txt
This would instantly 'create' folder1 and folder2. Or, to be more accurate, the folders would 'appear' but they don't actually exist because the full filename (Key) of the object is folder1/folder2/foo.txt.
If you were then to delete that object, the folders would 'disappear' because they never actually existed.
Sometimes, if a system wants to forcefully make a folder 'appear', it can create a zero-length object with the same name as the folder. This makes the folder 'appear', but it is really the empty file that is appearing.
Bottom line: Don't worry about creating and deleting folders. They will appear when necessary and disappear when not being used. Do not try to map normal filesystem behaviour to Amazon S3.
I have to replicate my local folder structure in S3 bucket, I am able to do so but its not creating folders which are empty. My local folder structure is as follows and command used is.
"aws-exec s3 sync ./inbound s3://msit.xxwmm.supplychain.relex.eeeeeeeeee/
its only creating inbound/procurement/pending/test.txt, masterdata and transaction is not cretated but if i put some file in each directory it will create.
As answered by #SabeenMalik in this StackOverflow thread:
S3 doesn't have the concept of directories, the whole folder/file.jpg
is the file name. If using a GUI tool or something you delete the
file.jpg from inside the folder, you will most probably see that the
folder is gone too. The visual representation in terms of directories
is for user convenience.
You do not need to pre-create the directory structure. Just pretend that the structure is there and everything will be okay.
Amazon S3 will automatically create the structure as objects are written to paths. For example, creating an object called s3://bucketname/inbound/procurement/foo` will automatically create the directories.
(This isn't strictly true because Amazon S3 doesn't use directories, but it will appear that the directories are there.)
I want to delete files from s3 bucket. Inside test bucket, there is a folder named mi and inside mi archive.
I configured life cycle rule on test bucket to delete file abc.txt from test/mi/archive/abc.txt after 7 days. I want to delete only abc.txt but it deletes full archive folder not only file.
At the time of rule apply on test bucket, I gave prefix mi/archive/.
S3 doesn't have folders, only object key prefixes. If there is no object with mi/archive in the prefix then that "folder" is not going to appear.
This really shouldn't be an issue. The next time you upload an object with mi/archive prefix in the key the "folder" will appear again.
Thanks to all for giving suggestion....
Finally, I got a solution. I did some changes in prefix. In place of "mi/archive", i gave files starting letters because my all files starts with "cd". Suppose there is a file named "cd_abcd.txt". So at the time of rule configuration on "test" bucket, i putted prefix "mi/archive/cd". So after 7 days, only files will be delete not full "archive" folder.
lifecycling is only for the entire folder/bucket. Your best/cheapest bet is probably a scheduled lambda to check for the file, it's creation date, and delete if necessary.