There seems to be some inconsistency in Amazon S3's behavior.
If in bucket a "Bucket1", I create folder "Folder1" and upload a file say "sample.txt" into it. Next I delete this file. At the bucket level I can see "Folder1" on S3 Console.
Now in the same bucket if I upload a file "Folder2/sample.txt" and just delete sample.txt file, then Folder2 also disappears from console?
Why this inconsistency? AFAIK we do not have any API to create/delete folder at SDK level.
Am I missing something here or is this an actual issue?
Thanks in advance for any help.
A "Folder" in S3 is simply a 0-byte object with a / character at the end of the key name.
So, using the AWS CLI or SDKs, you can "create a folder" by "putting" an object that matches those criteria.
The AWS Management Console also does something extra: it simulates folders, even of they were not explicitly created. So, if you uploaded your object as "Folder2/sample.txt", it extrapolates and simulates "Folder2/" at the parent folder level. You can do this yourself with the CLI/SDKs using the delimiter parameter.
When you delete that object, since "Folder2" did not actually exist as a 0-byte object ending with / (see first paragraph), then "Folder2/" disappears from the management console.
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.
I am trying to list all items with specific prefix in S3 bucket. Here is directory structure that I have:
Item1/
Item2/
Item3/
Item4/
image_1.jpg
Item5/
image_1.jpg
image_2.jpg
When I set prefex to be Item1/Item2, I get as a result following keys:
Item1/Item2/
Item1/Item2/Item3/Item4/image_1.jpg
Item1/Item2/Item3/Item5/image_1.jpg
Item1/Item2/Item3/Item5/image_2.jpg
What I would like to get is:
Item1/Item2/
Item1/Item2/Item3
Item1/Item2/Item3/Item4
Item1/Item2/Item3/Item5
Item1/Item2/Item3/Item4/image_1.jpg
Item1/Item2/Item3/Item5/image_1.jpg
Item1/Item2/Item3/Item5/image_2.jpg
Is there anyway to achieve this in golang?
Folders do not actually exist in Amazon S3. It is a flat object storage system.
For example, using the AWS Command-Line Interface (CLI) I could copy a command to an Amazon S3 bucket:
aws s3 cp foo.txt s3://my-bucket/folder1/folder2/foo.txt
This work just fine, even though folder1 and folder2 do not exist. This is because objects are stored with a Key (filename) that includes the full path of the object. So, the above object actually has a Key (filename) of:
folder1/folder2/foo.txt
However, to make things easier for humans, the Amazon S3 management console makes it appear as though there are folders. In S3, these are called Common Prefixes rather than folders.
So, when you make an API call to list the contents of the bucket while specifying a Prefix, it simply says "List all objects whose Key starts with this string".
Your listing doesn't show any folders because they don't actually exist.
Now, just to contradict myself, it actually is possible to create a folder (eg by clicking Create folder in the management console). This actually creates a zero-length object with the same name as the folder. The folder will then appear in listings because it is actually listing the zero-length object rather than the folder.
This is probably why Item1/Item2/ appears in your listing, but Item1/Item2/Item3 does not. Somebody, at some stage, must have "created a folder" called Item1/Item2/, which actually created a zero-length object with that Key.
I have a bucket already created but I want to create new folders inside this bucket, not upload data or anything else, just create new folders. How can I do this ?
Thanks
AWS S3 doesn't really have a first class concept of a "folder" or "directory". S3 objects have prefixes, which are segmented by slashes, so there is certainly the appearance of folders, but it is not possible to have a truly empty directory structure.
However, their AWS Console user experience does present content as such, and provides a button to "Create Folder". When using that button, the UI provides the below message:
When you create a folder, S3 console creates an object with the above
name appended by suffix "/" and that object is displayed as a folder
in the S3 console.
You could try using PowerShell's Put Object API/cmdlet to create empty objects named per that instruction. For example, you could create a folder named "my-new-folder" by creating an object named "my-new-folder/".
S3 is object storage; it's not a regular file system. Generally speaking, there is no need to attempt to create folders. Simply upload objects, for example teams/east/falcons/logo.png.
If you really, really want to give the impression that there are folders then you can create zero-sized objects whose names ends in / (or whatever your preferred folder delimiter is). The simplest way to do this is with the AWS S3 console but any SDK will let you do it too (simply issue a PutObject with no body).
I was seaching for this myself and found this.
use -content where content = key then -file or -folder are not needed
$s3Path = "/folder/" + 'subfolder/'
Write-S3Object -BucketName $s3Bucket -Key $s3Path -Content $s3Path
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 want to download a directory from my s3.
When I need a file, the s3 management console (aws web console) allows me to download it, but when a directory, I have to use aws-cli, like:
$ aws s3 cp s3://mybucket/mydirectory/ . --recursive
My question is: Is there any way to get the s3 uri (s3://mybucket/mydirectory/) from s3 management console?
It's URL is available, but it is slightly different from s3 URI required by aws-cli. I could not find any menu to get the uri.
Thank you in advance!
No, it is not displayed in the console. However, it is simply:
s3://<bucket-name>/<key>
Directories are actually part of the key. For example, foo.jpg stored in an images directory will actually have a key (filename) of images/foo.jpg.
(self-answer)
Because it seems there was no such way, I have created one:
pip install aws-s3-url2uri
And command aws_s3_url2uri will be available after installation.
This command internally converts the web console URLs to S3 URIs, so works with URLs and URIs and local paths:
aws_s3_url2uri ls "https://console.aws.amazon.com/s3/home?region=<regionname>#&bucket=mybucket&prefix=mydir/mydir2/"
calls
aws s3 ls s3://mybucket/mydir/mydir2/
internally.
To convert an S3 URL displayed in the console such as https://s3.us-east-2.amazonaws.com/my-bucket-name/filename to an S3 URI, remove the https://s3.us-east-2.amazonaws.com/ portion and replace it with s3://, like so:
s3://my-bucket-name/filename
It looks like this feature is now available in the AWS Web Console.
It is accessible in two ways:
Selecting the checkbox next to the file and clicking on "Copy S3 URI" button.
Clicking on the file, and clicking on the "Copy S3 URI" button on the top right.
You can get the value from the console by selecting the file in the console. Choose Copy path on the Overview tab to copy the S3:// link to the object.
It is possible to get the S3-URI for a proper key/file in the console, by selecting the key and clicking on the Copy path button, this will place the s3-URI for the file on the clipboard.
However, directories are not keys as such but just key prefixes, so this will not work for them.
You may fail to get s3uri if you are created a new bucket.
You can get s3uri after creating a new folder in your bucket >> select check box to the newly created folder >> then copy the s3uri that appears at the top.