ObjectSummary / Action / get

get#

S3.ObjectSummary.get(**kwargs)#

Retrieves objects from Amazon S3. To use GET, you must have READ access to the object. If you grant READ access to the anonymous user, you can return the object without using an authorization header.

An Amazon S3 bucket has no directory hierarchy such as you would find in a typical computer file system. You can, however, create a logical hierarchy by using object key names that imply a folder structure. For example, instead of naming an object sample.jpg, you can name it photos/2006/February/sample.jpg.

To get an object from such a logical hierarchy, specify the full key name for the object in the GET operation. For a virtual hosted-style request example, if you have the object photos/2006/February/sample.jpg, specify the resource 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 resource as /examplebucket/photos/2006/February/sample.jpg. For more information about request types, see HTTP Host Header Bucket Specification.

For more information about returning the ACL of an object, see GetObjectAcl.

If the object you are retrieving is stored in the S3 Glacier or S3 Glacier Deep Archive storage class, or S3 Intelligent-Tiering Archive or S3 Intelligent-Tiering Deep Archive tiers, before you can retrieve the object you must first restore a copy using RestoreObject. Otherwise, this action returns an InvalidObjectStateError error. For information about restoring archived objects, see Restoring Archived Objects.

Encryption request headers, like x-amz-server-side-encryption, should not be sent for GET requests if your object uses server-side encryption with KMS keys (SSE-KMS) or server-side encryption with Amazon S3–managed encryption keys (SSE-S3). If your object does use these types of keys, you’ll get an HTTP 400 BadRequest error.

If you encrypt an object by using server-side encryption with customer-provided encryption keys (SSE-C) when you store the object in Amazon S3, then when you GET the object, you must use the following headers:

  • x-amz-server-side-encryption-customer-algorithm

  • x-amz-server-side-encryption-customer-key

  • x-amz-server-side-encryption-customer-key-MD5

For more information about SSE-C, see Server-Side Encryption (Using Customer-Provided Encryption Keys).

Assuming you have the relevant permission to read object tags, the response also returns the x-amz-tagging-count header that provides the count of number of tags associated with the object. You can use GetObjectTagging to retrieve the tag set associated with an object.

Permissions

You need the relevant read object (or version) permission for this operation. For more information, see Specifying Permissions in a Policy. If the object you request does not exist, the error 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 will return an HTTP status code 404 (“no such key”) error.

  • If you don’t have the s3:ListBucket permission, Amazon S3 will return an HTTP status code 403 (“access denied”) error.

Versioning

By default, the GET action returns the current version of an object. To return a different version, use the versionId subresource.

Note

  • If you supply a versionId, you need the s3:GetObjectVersion permission to access a specific version of an object. If you request a specific version, you do not need to have the s3:GetObject permission.

  • If the current version of the object is a delete marker, Amazon S3 behaves as if the object was deleted and includes x-amz-delete-marker: true in the response.

For more information about versioning, see PutBucketVersioning.

Overriding Response Header Values

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

You can override values for a set of response headers using the following query parameters. These response header values are sent only on a successful request, that is, when status code 200 OK is returned. The set of headers you can override using these parameters is a subset of the headers that Amazon S3 accepts when you create an object. The response headers that you can override for the GET response are Content-Type, Content-Language, Expires, Cache-Control, Content-Disposition, and Content-Encoding. To override these header values in the GET response, you use the following request parameters.

Note

You must sign the request, either using an Authorization header or a presigned URL, when using these parameters. They cannot be used with an unsigned (anonymous) request.

  • response-content-type

  • response-content-language

  • response-expires

  • response-cache-control

  • response-content-disposition

  • response-content-encoding

Additional Considerations about Request Headers

If both of the If-Match and If-Unmodified-Since headers are present in the request as follows: If-Match condition evaluates to true, and; If-Unmodified-Since condition evaluates to false; then, S3 returns 200 OK and the data requested.

If both of the If-None-Match and If-Modified-Since headers are present in the request as follows: `` If-None-Match`` condition evaluates to false, and; If-Modified-Since condition evaluates to true; then, S3 returns 304 Not Modified response code.

For more information about conditional requests, see RFC 7232.

The following operations are related to GetObject:

See also: AWS API Documentation

Request Syntax

response = object_summary.get(
    IfMatch='string',
    IfModifiedSince=datetime(2015, 1, 1),
    IfNoneMatch='string',
    IfUnmodifiedSince=datetime(2015, 1, 1),
    Range='string',
    ResponseCacheControl='string',
    ResponseContentDisposition='string',
    ResponseContentEncoding='string',
    ResponseContentLanguage='string',
    ResponseContentType='string',
    ResponseExpires=datetime(2015, 1, 1),
    VersionId='string',
    SSECustomerAlgorithm='string',
    SSECustomerKey='string',
    RequestPayer='requester',
    PartNumber=123,
    ExpectedBucketOwner='string',
    ChecksumMode='ENABLED'
)
Parameters:
  • IfMatch (string) – Return the object only if its entity tag (ETag) is the same as the one specified; otherwise, return a 412 (precondition failed) error.

  • IfModifiedSince (datetime) – Return the object only if it has been modified since the specified time; otherwise, return a 304 (not modified) error.

  • IfNoneMatch (string) – Return the object only if its entity tag (ETag) is different from the one specified; otherwise, return a 304 (not modified) error.

  • IfUnmodifiedSince (datetime) – Return the object only if it has not been modified since the specified time; otherwise, return a 412 (precondition failed) error.

  • Range (string) –

    Downloads the specified range bytes of an object. For more information about the HTTP Range header, see https://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.35.

    Note

    Amazon S3 doesn’t support retrieving multiple ranges of data per GET request.

  • ResponseCacheControl (string) – Sets the Cache-Control header of the response.

  • ResponseContentDisposition (string) – Sets the Content-Disposition header of the response

  • ResponseContentEncoding (string) – Sets the Content-Encoding header of the response.

  • ResponseContentLanguage (string) – Sets the Content-Language header of the response.

  • ResponseContentType (string) – Sets the Content-Type header of the response.

  • ResponseExpires (datetime) – Sets the Expires header of the response.

  • VersionId (string) – VersionId used to reference a specific version of the object.

  • SSECustomerAlgorithm (string) – Specifies the algorithm to use to when decrypting the object (for example, AES256).

  • SSECustomerKey (string) – Specifies the customer-provided encryption key for Amazon S3 used to encrypt the data. This value is used to decrypt the object when recovering it and must match the one used when storing the data. The key must be appropriate for use with the algorithm specified in the x-amz-server-side-encryption-customer-algorithm header.

  • SSECustomerKeyMD5 (string) –

    Specifies the 128-bit MD5 digest of the encryption key according to RFC 1321. Amazon S3 uses this header for a message integrity check to ensure that the encryption key was transmitted without error.

    Please note that this parameter is automatically populated if it is not provided. Including this parameter is not required

  • RequestPayer (string) – Confirms that the requester knows that they will be charged for the request. Bucket owners need not specify this parameter in their requests. For information about downloading objects from Requester Pays buckets, see Downloading Objects in Requester Pays Buckets in the Amazon S3 User Guide.

  • PartNumber (integer) – Part number of the object being read. This is a positive integer between 1 and 10,000. Effectively performs a ‘ranged’ GET request for the part specified. Useful for downloading just a part of an object.

  • ExpectedBucketOwner (string) – The account ID of the expected bucket owner. If the bucket is owned by a different account, the request fails with the HTTP status code 403 Forbidden (access denied).

  • ChecksumMode (string) – To retrieve the checksum, this mode must be enabled.

Return type:

dict

Returns:

Response Syntax

{
    'Body': StreamingBody(),
    'DeleteMarker': True|False,
    'AcceptRanges': 'string',
    'Expiration': 'string',
    'Restore': 'string',
    'LastModified': datetime(2015, 1, 1),
    'ContentLength': 123,
    'ETag': 'string',
    'ChecksumCRC32': 'string',
    'ChecksumCRC32C': 'string',
    'ChecksumSHA1': 'string',
    'ChecksumSHA256': 'string',
    'MissingMeta': 123,
    'VersionId': 'string',
    'CacheControl': 'string',
    'ContentDisposition': 'string',
    'ContentEncoding': 'string',
    'ContentLanguage': 'string',
    'ContentRange': 'string',
    'ContentType': 'string',
    'Expires': datetime(2015, 1, 1),
    'WebsiteRedirectLocation': 'string',
    'ServerSideEncryption': 'AES256'|'aws:kms',
    'Metadata': {
        'string': 'string'
    },
    'SSECustomerAlgorithm': 'string',
    'SSECustomerKeyMD5': 'string',
    'SSEKMSKeyId': 'string',
    'BucketKeyEnabled': True|False,
    'StorageClass': 'STANDARD'|'REDUCED_REDUNDANCY'|'STANDARD_IA'|'ONEZONE_IA'|'INTELLIGENT_TIERING'|'GLACIER'|'DEEP_ARCHIVE'|'OUTPOSTS'|'GLACIER_IR',
    'RequestCharged': 'requester',
    'ReplicationStatus': 'COMPLETE'|'PENDING'|'FAILED'|'REPLICA',
    'PartsCount': 123,
    'TagCount': 123,
    'ObjectLockMode': 'GOVERNANCE'|'COMPLIANCE',
    'ObjectLockRetainUntilDate': datetime(2015, 1, 1),
    'ObjectLockLegalHoldStatus': 'ON'|'OFF'
}

Response Structure

  • (dict) –

    • Body (StreamingBody) –

      Object data.

    • DeleteMarker (boolean) –

      Specifies whether the object retrieved was (true) or was not (false) a Delete Marker. If false, this response header does not appear in the response.

    • AcceptRanges (string) –

      Indicates that a range of bytes was specified.

    • Expiration (string) –

      If the object expiration is configured (see PUT Bucket lifecycle), the response includes this header. It includes the expiry-date and rule-id key-value pairs providing object expiration information. The value of the rule-id is URL-encoded.

    • Restore (string) –

      Provides information about object restoration action and expiration time of the restored object copy.

    • LastModified (datetime) –

      Creation date of the object.

    • ContentLength (integer) –

      Size of the body in bytes.

    • ETag (string) –

      An entity tag (ETag) is an opaque identifier assigned by a web server to a specific version of a resource found at a URL.

    • ChecksumCRC32 (string) –

      The base64-encoded, 32-bit CRC32 checksum of the object. This will only be present if it was uploaded with the object. With multipart uploads, this may not be a checksum value of the object. For more information about how checksums are calculated with multipart uploads, see Checking object integrity in the Amazon S3 User Guide.

    • ChecksumCRC32C (string) –

      The base64-encoded, 32-bit CRC32C checksum of the object. This will only be present if it was uploaded with the object. With multipart uploads, this may not be a checksum value of the object. For more information about how checksums are calculated with multipart uploads, see Checking object integrity in the Amazon S3 User Guide.

    • ChecksumSHA1 (string) –

      The base64-encoded, 160-bit SHA-1 digest of the object. This will only be present if it was uploaded with the object. With multipart uploads, this may not be a checksum value of the object. For more information about how checksums are calculated with multipart uploads, see Checking object integrity in the Amazon S3 User Guide.

    • ChecksumSHA256 (string) –

      The base64-encoded, 256-bit SHA-256 digest of the object. This will only be present if it was uploaded with the object. With multipart uploads, this may not be a checksum value of the object. For more information about how checksums are calculated with multipart uploads, see Checking object integrity in the Amazon S3 User Guide.

    • MissingMeta (integer) –

      This is set to the number of metadata entries not returned in x-amz-meta headers. This can happen if you create metadata using an API like SOAP that supports more flexible metadata than the REST API. For example, using SOAP, you can create metadata whose values are not legal HTTP headers.

    • VersionId (string) –

      Version of the object.

    • CacheControl (string) –

      Specifies caching behavior along the request/reply chain.

    • ContentDisposition (string) –

      Specifies presentational information for the object.

    • ContentEncoding (string) –

      Specifies what content encodings have been applied to the object and thus what decoding mechanisms must be applied to obtain the media-type referenced by the Content-Type header field.

    • ContentLanguage (string) –

      The language the content is in.

    • ContentRange (string) –

      The portion of the object returned in the response.

    • ContentType (string) –

      A standard MIME type describing the format of the object data.

    • Expires (datetime) –

      The date and time at which the object is no longer cacheable.

    • WebsiteRedirectLocation (string) –

      If the bucket is configured as a website, redirects requests for this object to another object in the same bucket or to an external URL. Amazon S3 stores the value of this header in the object metadata.

    • ServerSideEncryption (string) –

      The server-side encryption algorithm used when storing this object in Amazon S3 (for example, AES256, aws:kms).

    • Metadata (dict) –

      A map of metadata to store with the object in S3.

      • (string) –

        • (string) –

    • SSECustomerAlgorithm (string) –

      If server-side encryption with a customer-provided encryption key was requested, the response will include this header confirming the encryption algorithm used.

    • SSECustomerKeyMD5 (string) –

      If server-side encryption with a customer-provided encryption key was requested, the response will include this header to provide round-trip message integrity verification of the customer-provided encryption key.

    • SSEKMSKeyId (string) –

      If present, specifies the ID of the Amazon Web Services Key Management Service (Amazon Web Services KMS) symmetric customer managed key that was used for the object.

    • BucketKeyEnabled (boolean) –

      Indicates whether the object uses an S3 Bucket Key for server-side encryption with Amazon Web Services KMS (SSE-KMS).

    • StorageClass (string) –

      Provides storage class information of the object. Amazon S3 returns this header for all objects except for S3 Standard storage class objects.

    • RequestCharged (string) –

      If present, indicates that the requester was successfully charged for the request.

    • ReplicationStatus (string) –

      Amazon S3 can return this if your request involves a bucket that is either a source or destination in a replication rule.

    • PartsCount (integer) –

      The count of parts this object has. This value is only returned if you specify partNumber in your request and the object was uploaded as a multipart upload.

    • TagCount (integer) –

      The number of tags, if any, on the object.

    • ObjectLockMode (string) –

      The Object Lock mode currently in place for this object.

    • ObjectLockRetainUntilDate (datetime) –

      The date and time when this object’s Object Lock will expire.

    • ObjectLockLegalHoldStatus (string) –

      Indicates whether this object has an active legal hold. This field is only returned if you have permission to view an object’s legal hold status.