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httr (version 1.4.7)

HEAD: Get url HEADers.

Description

Get url HEADers.

Usage

HEAD(url = NULL, config = list(), ..., handle = NULL)

Value

A response() object.

Arguments

url

the url of the page to retrieve

config

Additional configuration settings such as http authentication (authenticate()), additional headers (add_headers()), cookies (set_cookies()) etc. See config() for full details and list of helpers.

...

Further named parameters, such as query, path, etc, passed on to modify_url(). Unnamed parameters will be combined with config().

handle

The handle to use with this request. If not supplied, will be retrieved and reused from the handle_pool() based on the scheme, hostname and port of the url. By default httr requests to the same scheme/host/port combo. This substantially reduces connection time, and ensures that cookies are maintained over multiple requests to the same host. See handle_pool() for more details.

RFC2616

The HEAD method is identical to GET except that the server MUST NOT return a message-body in the response. The metainformation contained in the HTTP headers in response to a HEAD request SHOULD be identical to the information sent in response to a GET request. This method can be used for obtaining metainformation about the entity implied by the request without transferring the entity-body itself. This method is often used for testing hypertext links for validity, accessibility, and recent modification.

The response to a HEAD request MAY be cacheable in the sense that the information contained in the response MAY be used to update a previously cached entity from that resource. If the new field values indicate that the cached entity differs from the current entity (as would be indicated by a change in Content-Length, Content-MD5, ETag or Last-Modified), then the cache MUST treat the cache entry as stale.

See Also

Other http methods: BROWSE(), DELETE(), GET(), PATCH(), POST(), PUT(), VERB()

Examples

Run this code
HEAD("http://google.com")
headers(HEAD("http://google.com"))

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