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@aws-sdk/client-s3

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AWS SDK for JavaScript S3 Client for Node.js, Browser and React Native

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import { S3ClientResolvedConfig, ServiceInputTypes, ServiceOutputTypes } from "../S3Client"; import { HeadObjectOutput, HeadObjectRequest } from "../models/models_0"; import { Command as $Command } from "@aws-sdk/smithy-client"; import { Handler, MiddlewareStack, HttpHandlerOptions as __HttpHandlerOptions, MetadataBearer as __MetadataBearer } from "@aws-sdk/types"; export declare type HeadObjectCommandInput = HeadObjectRequest; export declare type HeadObjectCommandOutput = HeadObjectOutput & __MetadataBearer; /** * <p>The HEAD operation retrieves metadata from an object without returning the object * itself. This operation is useful if you're only interested in an object's metadata. To use * HEAD, you must have READ access to the object.</p> * * <p>A <code>HEAD</code> request has the same options as a <code>GET</code> operation on an * object. The response is identical to the <code>GET</code> response except that there is no * response body.</p> * * <p>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 retrieve the * metadata from the object, you must use the following headers:</p> * <ul> * <li> * <p>x-amz-server-side-encryption-customer-algorithm</p> * </li> * <li> * <p>x-amz-server-side-encryption-customer-key</p> * </li> * <li> * <p>x-amz-server-side-encryption-customer-key-MD5</p> * </li> * </ul> * <p>For more information about SSE-C, see <a href="https://docs.aws.amazon.com/AmazonS3/latest/dev/ServerSideEncryptionCustomerKeys.html">Server-Side Encryption (Using * Customer-Provided Encryption Keys)</a>.</p> * <note> * <p>Encryption request headers, like <code>x-amz-server-side-encryption</code>, should * not be sent for GET requests if your object uses server-side encryption with CMKs stored * in AWS KMS (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.</p> * </note> * * * * * * * * <p>Request headers are limited to 8 KB in size. For more information, see <a href="https://docs.aws.amazon.com/AmazonS3/latest/API/RESTCommonRequestHeaders.html">Common Request * Headers</a>.</p> * <p>Consider the following when using request headers:</p> * <ul> * <li> * <p> Consideration 1 – If both of the <code>If-Match</code> and * <code>If-Unmodified-Since</code> headers are present in the request as * follows:</p> * <ul> * <li> * <p> * <code>If-Match</code> condition evaluates to <code>true</code>, and;</p> * </li> * <li> * <p> * <code>If-Unmodified-Since</code> condition evaluates to * <code>false</code>;</p> * </li> * </ul> * <p>Then Amazon S3 returns <code>200 OK</code> and the data requested.</p> * </li> * <li> * <p> Consideration 2 – If both of the <code>If-None-Match</code> and * <code>If-Modified-Since</code> headers are present in the request as * follows:</p> * <ul> * <li> * <p> * <code>If-None-Match</code> condition evaluates to <code>false</code>, * and;</p> * </li> * <li> * <p> * <code>If-Modified-Since</code> condition evaluates to * <code>true</code>;</p> * </li> * </ul> * <p>Then Amazon S3 returns the <code>304 Not Modified</code> response code.</p> * </li> * </ul> * * <p>For more information about conditional requests, see <a href="https://tools.ietf.org/html/rfc7232">RFC 7232</a>.</p> * * <p> * <b>Permissions</b> * </p> * <p>You need the <code>s3:GetObject</code> permission for this operation. For more * information, see <a href="https://docs.aws.amazon.com/AmazonS3/latest/dev/using-with-s3-actions.html">Specifying Permissions * in a Policy</a>. If the object you request does not exist, the error Amazon S3 returns * depends on whether you also have the s3:ListBucket permission.</p> * <ul> * <li> * <p>If you have the <code>s3:ListBucket</code> permission on the bucket, Amazon S3 returns * an HTTP status code 404 ("no such key") error.</p> * </li> * <li> * <p>If you don’t have the <code>s3:ListBucket</code> permission, Amazon S3 returns an HTTP * status code 403 ("access denied") error.</p> * </li> * </ul> * * <p>The following operation is related to <code>HeadObject</code>:</p> * <ul> * <li> * <p> * <a href="https://docs.aws.amazon.com/AmazonS3/latest/API/API_GetObject.html">GetObject</a> * </p> * </li> * </ul> */ export declare class HeadObjectCommand extends $Command<HeadObjectCommandInput, HeadObjectCommandOutput, S3ClientResolvedConfig> { readonly input: HeadObjectCommandInput; constructor(input: HeadObjectCommandInput); /** * @internal */ resolveMiddleware(clientStack: MiddlewareStack<ServiceInputTypes, ServiceOutputTypes>, configuration: S3ClientResolvedConfig, options?: __HttpHandlerOptions): Handler<HeadObjectCommandInput, HeadObjectCommandOutput>; private serialize; private deserialize; }