AWS SDK Version 3 for .NET
API Reference

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Retrieves an object from Amazon S3.

In the GetObject request, specify the full key name for the object.

General purpose buckets - Both the virtual-hosted-style requests and the path-style requests are supported. For a virtual hosted-style request example, if you have the object photos/2006/February/sample.jpg, specify the object key name as /photos/2006/February/sample.jpg. For a path-style request example, if you have the object photos/2006/February/sample.jpg in the bucket named examplebucket, specify the object key name as /examplebucket/photos/2006/February/sample.jpg. For more information about request types, see HTTP Host Header Bucket Specification in the Amazon S3 User Guide.

Directory buckets - Only virtual-hosted-style requests are supported. For a virtual hosted-style request example, if you have the object photos/2006/February/sample.jpg in the bucket named examplebucket--use1-az5--x-s3, specify the object key name as /photos/2006/February/sample.jpg. Also, when you make requests to this API operation, your requests are sent to the Zonal endpoint. These endpoints support virtual-hosted-style requests in the format https://bucket_name.s3express-az_id.region.amazonaws.com/key-name. Path-style requests are not supported. For more information, see Regional and Zonal endpoints in the Amazon S3 User Guide.

Permissions
  • General purpose bucket permissions - You must have the required permissions in a policy. To use GetObject, you must have the READ access to the object (or version). If you grant READ access to the anonymous user, the GetObject operation returns the object without using an authorization header. For more information, see Specifying permissions in a policy in the Amazon S3 User Guide.

    If you include a versionId in your request header, you must have the s3:GetObjectVersion permission to access a specific version of an object. The s3:GetObject permission is not required in this scenario.

    If you request the current version of an object without a specific versionId in the request header, only the s3:GetObject permission is required. The s3:GetObjectVersion permission is not required in this scenario.

    If the object that you request doesn’t exist, the error that Amazon S3 returns depends on whether you also have the s3:ListBucket permission.

    • If you have the s3:ListBucket permission on the bucket, Amazon S3 returns an HTTP status code 404 Not Found error.

    • If you don’t have the s3:ListBucket permission, Amazon S3 returns an HTTP status code 403 Access Denied error.

  • Directory bucket permissions - To grant access to this API operation on a directory bucket, we recommend that you use the CreateSession API operation for session-based authorization. Specifically, you grant the s3express:CreateSession permission to the directory bucket in a bucket policy or an IAM identity-based policy. Then, you make the CreateSession API call on the bucket to obtain a session token. With the session token in your request header, you can make API requests to this operation. After the session token expires, you make another CreateSession API call to generate a new session token for use. Amazon Web Services CLI or SDKs create session and refresh the session token automatically to avoid service interruptions when a session expires. For more information about authorization, see CreateSession.

Storage classes

If the object you are retrieving is stored in the S3 Glacier Flexible Retrieval storage class, the S3 Glacier Deep Archive storage class, the S3 Intelligent-Tiering Archive Access tier, or the S3 Intelligent-Tiering Deep Archive Access tier, before you can retrieve the object you must first restore a copy using RestoreObject. Otherwise, this operation returns an InvalidObjectState error. For information about restoring archived objects, see Restoring Archived Objects in the Amazon S3 User Guide.

Directory buckets - For directory buckets, only the S3 Express One Zone storage class is supported to store newly created objects. Unsupported storage class values won't write a destination object and will respond with the HTTP status code 400 Bad Request.

Encryption

Encryption request headers, like x-amz-server-side-encryption, should not be sent for the GetObject requests, if your object uses server-side encryption with Amazon S3 managed encryption keys (SSE-S3), server-side encryption with Key Management Service (KMS) keys (SSE-KMS), or dual-layer server-side encryption with Amazon Web Services KMS keys (DSSE-KMS). If you include the header in your GetObject requests for the object that uses these types of keys, you’ll get an HTTP 400 Bad Request error.

Overriding response header values through the request

There are times when you want to override certain response header values of a GetObject response. For example, you might override the Content-Disposition response header value through your GetObject request.

You can override values for a set of response headers. These modified response header values are included only in a successful response, that is, when the HTTP status code 200 OK is returned. The headers you can override using the following query parameters in the request are a subset of the headers that Amazon S3 accepts when you create an object.

The response headers that you can override for the GetObject response are Cache-Control, Content-Disposition, Content-Encoding, Content-Language, Content-Type, and Expires.

To override values for a set of response headers in the GetObject response, you can use the following query parameters in the request.

  • response-cache-control

  • response-content-disposition

  • response-content-encoding

  • response-content-language

  • response-content-type

  • response-expires

When you use these parameters, you must sign the request by using either an Authorization header or a presigned URL. These parameters cannot be used with an unsigned (anonymous) request.

HTTP Host header syntax

Directory buckets - The HTTP Host header syntax is Bucket_name.s3express-az_id.region.amazonaws.com.

The following operations are related to GetObject:

Note:

For .NET Core this operation is only available in asynchronous form. Please refer to GetObjectAsync.

Namespace: Amazon.S3
Assembly: AWSSDK.S3.dll
Version: 3.x.y.z

Syntax

C#
public virtual GetObjectResponse GetObject(
         String bucketName,
         String key,
         String versionId
)

Parameters

bucketName
Type: System.String

The bucket name containing the object. Directory buckets - When you use this operation with a directory bucket, you must use virtual-hosted-style requests in the format Bucket_name.s3express-az_id.region.amazonaws.com. Path-style requests are not supported. Directory bucket names must be unique in the chosen Availability Zone. Bucket names must follow the format bucket_base_name--az-id--x-s3 (for example, DOC-EXAMPLE-BUCKET--usw2-az2--x-s3). For information about bucket naming restrictions, see Directory bucket naming rules in the Amazon S3 User Guide. Access points - When you use this action with an access point, you must provide the alias of the access point in place of the bucket name or specify the access point ARN. When using the access point ARN, you must direct requests to the access point hostname. The access point hostname takes the form AccessPointName-AccountId.s3-accesspoint.Region.amazonaws.com. When using this action with an access point through the Amazon Web Services SDKs, you provide the access point ARN in place of the bucket name. For more information about access point ARNs, see Using access points in the Amazon S3 User Guide. Object Lambda access points - When you use this action with an Object Lambda access point, you must direct requests to the Object Lambda access point hostname. The Object Lambda access point hostname takes the form AccessPointName-AccountId.s3-object-lambda.Region.amazonaws.com. Access points and Object Lambda access points are not supported by directory buckets. S3 on Outposts - When you use this action with Amazon S3 on Outposts, you must direct requests to the S3 on Outposts hostname. The S3 on Outposts hostname takes the form AccessPointName-AccountId.outpostID.s3-outposts.Region.amazonaws.com. When you use this action with S3 on Outposts through the Amazon Web Services SDKs, you provide the Outposts access point ARN in place of the bucket name. For more information about S3 on Outposts ARNs, see What is S3 on Outposts? in the Amazon S3 User Guide.

key
Type: System.String

Key of the object to get.

versionId
Type: System.String

Version ID used to reference a specific version of the object. By default, the GetObject operation returns the current version of an object. To return a different version, use the versionId subresource. If you include a versionId in your request header, you must have the s3:GetObjectVersion permission to access a specific version of an object. The s3:GetObject permission is not required in this scenario. If you request the current version of an object without a specific versionId in the request header, only the s3:GetObject permission is required. The s3:GetObjectVersion permission is not required in this scenario. Directory buckets - S3 Versioning isn't enabled and supported for directory buckets. For this API operation, only the null value of the version ID is supported by directory buckets. You can only specify null to the versionId query parameter in the request. For more information about versioning, see PutBucketVersioning.

Return Value


The response from the GetObject service method, as returned by S3.

Version Information

.NET Framework:
Supported in: 4.5, 4.0, 3.5

See Also