Download the Amazon S3 file and get the URL

Question

Is it possible to upload a txt / pdf / png file to Amazon S3 in one step and get the URL of the downloaded file as an answer. If so, is the AWS Java SDK a suitable library that I need to add to my java struts2 web application.

Please suggest me a solution for this.

Answer 1

To make the file open before downloading, you can use the #withCannedAcl PutObjectRequest method:

 myAmazonS3Client.putObject(new PutObjectRequest('some-grails-bucket', 'somePath/someKey.jpg', new File('/Users/ben/Desktop/photo.jpg')).withCannedAcl(CannedAccessControlList.PublicRead)) 

Answer 2

No, you can’t get the URL in one action, but two :)

First of all, you may need to make the file public before downloading, because it makes no sense to get a URL that no one can access. You can do this by setting the ACL as suggested by Michael Astreiko. You can get the resource URL by calling getResourceUrl or getUrl .

 AmazonS3Client s3Client = (AmazonS3Client)AmazonS3ClientBuilder.defaultClient(); s3Client.putObject(new PutObjectRequest("your-bucket", "some-path/some-key.jpg", new File("somePath/someKey.jpg")).withCannedAcl(CannedAccessControlList.PublicRead)) s3Client.getResourceUrl("your-bucket", "some-path/some-key.jpg"); 

Note getResourceUrl difference between getResourceUrl and getUrl is that getResourceUrl will return zero when an exception occurs.

Note 2: the getUrl method getUrl not defined in the AmazonS3 interface. You must cast the object to AmazonS3Client if you use the standard linker.

Answer 3

You can solve this problem yourself and specify the file name specified in the download request.

eg. if your bucket is mybucket and your file has the name myfilename :

 https://mybucket.s3.amazonaws.com/myfilename 

The s3 bit will differ depending on what area your bucket is in. For example, I use the region of Southeast Asia, so my URLs are similar to:

 https://mybucket.s3-ap-southeast-1.amazonaws.com/myfilename 

Answer 4

Similarly, if you want a link through s3Client, you can use below.

 System.out.println("filelink: " + s3Client.getUrl("your_bucket_name", "your_file_key")); 

Answer 5

a bit outdated, but still for those who stumble upon this in the future:

you can do this with a single line, assuming you have already written CredentialProvider and AmazonS3Client.

it will look like this:

  String ImageURL = String.valueOf(s3.getUrl( ConstantsAWS3.BUCKET_NAME, //The S3 Bucket To Upload To file.getName())); //The key for the uploaded object 

and if you haven't written CredentialProvider and AmazonS3Client, just add them before getting the URL, for example:

  CognitoCachingCredentialsProvider credentialsProvider = new CognitoCachingCredentialsProvider( getApplicationContext(), "POOL_ID", // Identity pool ID Regions.US_EAST_1 // Region ); 

Answer 6

The answers from @hussachai and @Jeffrey Kemp are pretty good. But they have something in common: the return URL is made in the style of a virtual host, and not in the style of the path. For more information on s3 URL style, see AWS S3 URL Styles . In case some people want to have a path style, an s3 url is generated. Here is the step. Basically everything will be the same as @hussachai and @Jeffrey Kemp answers, with only one change to the string settings, as shown below:

 AmazonS3Client s3Client = (AmazonS3Client) AmazonS3ClientBuilder.standard() .withRegion("us-west-2") .withCredentials(DefaultAWSCredentialsProviderChain.getInstance()) .withPathStyleAccessEnabled(true) .build(); // Upload a file as a new object with ContentType and title specified. PutObjectRequest request = new PutObjectRequest(bucketName, stringObjKeyName, fileToUpload); s3Client.putObject(request); URL s3Url = s3Client.getUrl(bucketName, stringObjKeyName); logger.info("S3 url is " + s3Url.toExternalForm()); 

This will generate a URL like: https://s3.us-west-2.amazonaws.com/mybucket/myfilename

Answer 7

  System.out.println("Link : " + s3Object.getObjectContent().getHttpRequest().getURI()); 

however, you can get a link to an already downloaded file in the S3 basket.