Aws sdks3 download file

The S3 storage handles uploads to AWS S3 service (or any s3-compatible service such as DigitalOcean Spaces or MinIO). It requires the aws-sdk-s3 gem:

Initialization

The storage is initialized by providing your bucket name, region and credentials:

The storage requires the following AWS S3 permissions:

• for the bucket resource
• , , , , and for the object resources

The and options is just one form of authentication, see the AWS SDK docs for more options.

The storage exposes the underlying Aws objects:

Public uploads

By default, uploaded S3 objects will have private visibility, meaning they can only be accessed via signed expiring URLs generated using your private S3 credentials.

If you would like to generate public URLs, you can tell S3 storage to make uploads public:

If you want to make only some uploads public, you can conditionally apply the upload option and URL option:

Prefix

The option can be specified for uploading all files inside a specific S3 prefix (folder), which is useful when using S3 for both cache and store:

Upload options

Sometimes you'll want to add additional upload options to all S3 uploads. You can do that by passing the option:

These options will be passed to aws-sdk-s3's methods for uploading, copying and presigning.

You can also generate upload options per upload with the plugin

or when using the uploader directly

Unlike the storage option, upload options given on the uploader level won't be forwarded for generating presigns, since presigns are generated using the storage directly.

URL Host

If you want your S3 object URLs to be generated with a different URL host (e.g. a CDN), you can specify the option to :

The host URL can include a path prefix, but it needs to end with a slash:

To have the option passed automatically for every URL, use the plugin:

Signer

If you would like to serve private content via CloudFront, you need to sign the object URLs with a special signer, such as provided by the gem. The S3 storage initializer accepts a block, which you can use to call your signer:

URL options

Other than and URL options, all additional options are forwarded to .

Presigns

The method can be used for generating parameters for direct upload to S3:

By default, parameters for a POST upload is generated, but you can also generate PUT upload parameters:

Any additional options are forwarded to (for POST uploads) and (for PUT uploads).

Large files

The aws-sdk-s3 gem has the ability to automatically use multipart upload/copy for larger files, splitting the file into multiple chunks and uploading/copying them in parallel.

By default, multipart upload will be used for files larger than 15MB, and multipart copy for files larger than 100MB, but you can change the thresholds via :

Encryption

The easiest way to use server-side encryption for uploaded S3 objects is to configure default encryption for your S3 bucket. Alternatively, you can pass server-side encryption parameters to the API calls.

The method accepts options:

The method accepts options for POST presigns, and the same options as above for PUT presigns.

When downloading encrypted S3 objects, the same server-side encryption parameters need to be passed in.

Client-side encryption is supported as well:

Accelerate endpoint

To use Amazon S3's Transfer Acceleration feature, set to when initializing the storage:

Deleting prefixed

If you want to delete all objects in some prefix, you can use :

Clearing cache

If you're using S3 as a cache, you will probably want to periodically delete old files which aren't used anymore. S3 has a built-in way to do this, read this article for instructions.

Alternatively you can periodically call the method: