HEAD Object

Description

The HEAD object of QueryIO server fetches the metadata from an object. This is useful if user is only interested in metadata of object, since it does not return the object.

Requests

Syntax

Request Headers

The HEAD operation in QueryIO Server uses following request headers:

Header Name Description Type Defaults Constraints Required
If-Modified-Since

If the object has been modified after the specified time, it returns object.

String None None No
If-Unmodified-Since

If the object has not been modified after the specified time, it return object.

String None None No
If-Match

If the entity tag(ETag) of the object is same as the specified one, it returns the object.

String None None No
If-None-Match

If the entity tag(ETag) of the object is different from the specified one, it returns the object.

String None None No
fetch-metadata

Passing this argument as true will fetch metadata for files as response headers.

Value: true or false

Boolean - - No

Examples

Sample Request with the If-Modified-Since Header

The following request specifies the HTTP If-Modified-Since header to retrieve an object if it is modified after the given time.

Sample Response

Sample Request with the If-Unmodified-Since Header

The following request specifies the HTTP If-Unmodified-Since header to retrieve an object if it is not modified after the given time.

Sample Response

Sample Request with the If-Match Header

The following request specifies the HTTP If-Match header to retrieve an object if its entity tag is same as specified.

Sample Response

Sample Request with the If-None-Match Header

The following request specifies the HTTP If-None-Match header to retrieve an object if its entity tag is not same as specified.

Sample Response



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