HTTP_HEADER function [Web service]

HTTP_HEADER( header-field-name )

header-field-name The name of an HTTP request header field.

LONG VARCHAR

This function returns the value of the named HTTP request header field, or NULL if it does not exist or if it is not called from an HTTP service. It is used when processing an HTTP request via a web service.

Some headers that may be of interest when processing an HTTP web service request include the following:

Cookie The cookie value(s), if any, stored by the client, that are associated with the requested URI.
Referer The URL of the page that contained the link to the requested URI.
Host The name or IP of the host that submitted the request.
User-Agent The name of the client application.
Accept-Encoding A list of encodings for the response that are acceptable to the client application.

More information about these headers is available at [external link] http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html.

The following special headers allow access to the elements within the request line of a client request.

@HttpMethod Returns the type of request being processed. Possible values include DELETE, HEAD, GET, PUT, or POST.
@HttpURI The full URI of the request, as it was specified in the HTTP request (for example, /myservice?&id=-123&version=109&lang=en).
@HttpVersion The HTTP version of the request (for example, HTTP/1.0, or HTTP/1.1).
@HttpQueryString Returns the query portion of the requested URI if it exists (for example, &id=-123&version=109&lang=en).

SQL/2008 Vendor extension.

When used within a stored procedure that is called by an HTTP web service, the following example gets the Cookie header value:

SET cookie_value = HTTP_HEADER( 'Cookie' );

When used within a stored procedure that is called by an HTTP web service, the following example displays the name and values of the HTTP request headers in the database server messages window.

BEGIN
  declare header_name long varchar;
  declare header_value long varchar;
  set header_name  = NULL;
header_loop:        
  LOOP
    SET header_name = NEXT_HTTP_HEADER( header_name );
    IF header_name IS NULL THEN 
      LEAVE header_loop 
    END IF;
    SET header_value = HTTP_HEADER( header_name );
    MESSAGE 'HEADER: ', header_name, '=', 
            header_value TO CONSOLE;
  END LOOP;
END;

HTTP_HEADER function [Web service]

Syntax

Parameters

Returns

Remarks

See also

Standards and compatibility

Example