I use Java AWS S3 SDK to presign my requests. I have the following code:
var request = new GeneratePresignedUrlRequest(bucketName, filename)
.withMethod(method)
.withExpiration(expiration());
// do something with request
return s3Client.generatePresignedUrl(request);
What I need to write in place of comment to add custom conditions like content-length-range?
For browser-based POST uploads to S3, the AWS Java SDK doesn't provide a way to generate pre-signed URLs with conditions. There's an open feature request to add this to the v2 SDK. Note that the PHP, Node.js, and Python SDKs do all provide this feature.
For regular HTTP PUT pre-signed URLs, you can't apply content length restrictions to pre-signed URLs. You can place conditions using a custom policy but that only supports:
DateLessThan
DateGreaterThan
IpAddress
If you need to deal with objects outside of a given size range then you could potentially do that in AWS Lambda, after the object has been uploaded.
Related
I want to create a signed request for external users so they can upload a file to my s3 bucket. I want to have the following limitations
URL expiration time
limit size range
content type
I did some research and found out that there are 2 main ways to achieve this:
Presigned URL(PutObject API) https://docs.aws.amazon.com/AmazonS3/latest/API/API_PutObject.html
Post object(post policy with limitations specified)
https://docs.aws.amazon.com/AmazonS3/latest/API/RESTObjectPOST.html
but unfortunately, neither of these 2 ways supports all the limitations I need. To be precise, presigned URL doesn't allow to limit file range(only exact number of bytes to be uploaded), on the other hand, Post object doesn't support multipart upload(as far as I understood).
So the question is how can I achieve all the limitations and still be able to upload file in parallel(multipart) ?
I'm using java language and checked minio already, but didn't find anything. Maybe there is some API that is not supported in AWS SDK or minio implementations that allows doing this?
So we have a use case where we need to be able to download the S3 files from the outside world on the internet. For this we are creating s3 pre signed url as below. My doubt is how can we access this on the internet? Are these urls accessible by default on the internet. Or do we need to create a proxy.
https://<bucket-name>.s3.amazonaws.com/<filename><some other parameters>
The URL you are showing is not a Pre-signed URL. A Pre-signed URL look like this:
https://bucketxxxxxx.s3.amazonaws.com/note.txt?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20230117T153509Z&X-Amz-SignedHeaders=host&X-Amz-Expires=3599&X-Amz-Credential=AKIA33JWY3BX2TYWxxxxxxxxxxx%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Signature=e55142af548e46fc2870bb03331d0e9aa9ffbd21xxxxxxxxxxxxxxxxxx
Once you generate a valid Pre-signed URL, you do not need a proxy. A user can download the object in the given time window - which you define when you create GetObjectPresignRequest .
GetObjectPresignRequest getObjectPresignRequest = GetObjectPresignRequest.builder()
.signatureDuration(Duration.ofMinutes(60))
.getObjectRequest(getObjectRequest)
.build();
You can see the proper way to create a pre-signed URL using AWS SDK for Java v2 in the AWS Code Github here:
https://github.com/awsdocs/aws-doc-sdk-examples/blob/main/javav2/example_code/s3/src/main/java/com/example/s3/GetObjectPresignedUrl.java
TO read more about using the AWS SDK for Java v2 to create them, see this topic in the AWS Java V2 Developer Guide.
Working with Amazon S3 presigned URLs
I am trying to perform some S3 operations (like create bucket, get bucket, put object, list object etc) with V4 authentication using Query parameter as Authentication method.
I want to perform the operation using AWS JAVA SDKs
Question-
1. Does AWS JAVA SDK support Query parameter as Authentication method?If yes which package needs to be imported.
2. Any example of how to do that using AWS JAVA SDK will be greatly appreciated
You can generate pre-signed URL requests to access s3 resources using query parameter authentication. Here's how to do it with the Java SDK:
URL url = s3Client.generatePresignedUrl(bucketName, key, expirationDate);
I've only used it successfully with GET requests.
This might seem strange at first considering the easiest way is to work with the SDK, but it's not an option for me. The reason being, I'm actually building a Third Party API and allowing for the upload of files to my bucket.
The first person consuming my API is an android application and I'd like to get some idea as to the best way to make this possible.
I can't give 3rd party developers my AWS credentials.
I've authorised this on my website with Cross Origin Resource Sharing and signed requests. Is there a similar way to do this on android?
Ideally I'd like the flow to be:
3rd party app sends me the file info, key, etc.
my API service signs the request and sends it back.
The app then uses the request to upload the file.
Is this possible on Android?
I've read up on STS and creating temporary credentials, but that's still not nailing down permissions to a per-request level like the signed request method allows me to do.
You can use Browser based Form Upload feature offered by AWS for S3. Even though use case is described as browser upload, but it can be easily used by any http client.
Third Party Client (Android etc) calls your server to create a upload policy
Your server creates a signed policy by making AWS S3 API Call (YOu may use SDK to do that). This policy may allow upload for a particular key in S3.
The Android Client can submit the multi-part data using S3 key, signed policy.
Here is an example for HTML Form (You can easily use any http client to do for Android App) :
http://docs.aws.amazon.com/AmazonS3/latest/dev/HTTPPOSTExamples.html
This approach will only require your to share IAM Access key but not secret key.
Another alternative is to totally abstract S3 and let your server manage the upload:
I am currently using S3 with the Java API to get objects and their content. I've created a Cloudfront distribution using the AWS console and I set my S3 bucket with my objects as the Bucket-origin. But I didn't notice any improvement in the download performance, and I noticed in the console window the url refers to s3:
INFO: Sending Request: GET https://mybucket.s3.amazonaws.com /picture.jpg Headers: (Range: bytes=5001-1049479, Content-Type: application/x-www-form-urlencoded; charset=utf-8, )
whereas in the Getting Started guide for Cloudfront, the url should be:
http://(domain name)/picture.jpg
where (domain name) is specific to the Cloudfront distribution. So the Java API still is getting the file from S3 and not through cloudfront
Is there anyway using the Java API for S3 to download files via Cloudfront? If not, what's the best approach I should use to get objects via cloudfront in my java program? I am still kinda new to this stuff, any help greatly appreciated!
JAVA API for S3 can not be used for interacting with Cloudfront.
If you want to download the content through cloud front distribution, you have to write your own HTTP code (which should be simple). You can also just use http://(cloud front domain name)/picture.jpg in browser and check the download speed first.
URL url = new URL(your_cloudfront_url);
InputStream in = url.openStream();
But, you should know that it can take 24 hours or more for changes in S3 to be active.
If you cannot open the stream, the other way is to use getObject(bucketName, key) method.