Get url HEADers.

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

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

HEAD("http://google.com")
#> Response [http://www.google.com/] #> Date: 2017-08-16 14:12 #> Status: 200 #> Content-Type: text/html; charset=ISO-8859-1 #> <EMPTY BODY>
headers(HEAD("http://google.com"))
#> $date #> [1] "Wed, 16 Aug 2017 14:12:22 GMT" #> #> $expires #> [1] "-1" #> #> $`cache-control` #> [1] "private, max-age=0" #> #> $`content-type` #> [1] "text/html; charset=ISO-8859-1" #> #> $`content-encoding` #> [1] "gzip" #> #> $server #> [1] "gws" #> #> $`content-length` #> [1] "4526" #> #> $`x-xss-protection` #> [1] "1; mode=block" #> #> $`x-frame-options` #> [1] "SAMEORIGIN" #> #> attr(,"class") #> [1] "insensitive" "list"