allowing cached entities to be refreshed without requiring multiple
requests or transferring unnecessary data.
8.2 HEAD
The HEAD method is identical to GET except that the server must not
return any Entity-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 resource identified
by the Request-URI without transferring the Entity-Body itself. This
method is often used for testing hypertext links for validity,
accessibility, and recent modification.
There is no "conditional HEAD" request analogous to the conditional
GET. If an If-Modified-Since header field is included with a HEAD
request, it should be ignored.
8.3 POST
The POST method is used to request that the destination server accept
the entity enclosed in the request as a new subordinate of the
resource identified by the Request-URI in the Request-Line. POST is
designed to allow a uniform method to cover the following functions:
o Annotation of existing resources;
o Posting a message to a bulletin board, newsgroup, mailing list,
or similar group of articles;
o Providing a block of data, such as the result of submitting a
form [3], to a data-handling process;
o Extending a database through an append operation.
RFC 1945 HTTP/1.0 May 1996
The actual function performed by the POST method is determined by the
server and is usually dependent on the Request-URI. The posted entity
is subordinate to that URI in the same way that a file is subordinate
to a directory containing it, a news article is subordinate to a
newsgroup to which it is posted, or a record is subordinate to a
database.
A successful POST does not require that the entity be created as a
resource on the origin server or made accessible for future
reference. That is, the action performed by the POST method might not
result in a resource that can be identified by a URI. In this case,
either 200 (ok) or 204 (no content) is the appropriate response
status, depending on whether or not the response includes an entity
that describes the result.
If a resource has been created on the origin server, the response
should be 201 (created) and contain an entity (preferably of type
"text/html") which describes the status of the request and refers to
the new resource.
A valid Content-Length is required on all HTTP/1.0 POST requests. An
HTTP/1.0 server should respond with a 400 (bad request) message if it
cannot determine the length of the request message's content.
Applications must not cache responses to a POST request because the
application has no way of knowing that the server would return an
equivalent response on some future request.
9. Status Code Definitions
Each Status-Code is described below, including a description of which
method(s) it can follow and any metainformation required in the
response.
9.1 Informational 1xx
This class of status code indicates a provisional response,
consisting only of the Status-Line and optional headers, and is
terminated by an empty line. HTTP/1.0 does not define any 1xx status
codes and they are not a valid response to a HTTP/1.0 request.
However, they may be useful for experimental applications which are
outside the scope of this specification.
9.2 Successful 2xx
This class of status code indicates that the client's request was
successfully received, understood, and accepted.
RFC 1945 HTTP/1.0 May 1996
200 OK
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