Send (HttpRequest function)

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Send an HTTP request to the server (HttpRequest class)

The Send function sends an HTTP request to an HTTP server using a parameter value to identify which of the HTTP method types (GET, POST, DELETE, and so on) you want the function to perform. Any HTTP method type is valid as long as its name is 16 characters or less.

The HTTP method type is specified with the Method (name required) parameter. If the Method value is GET or POST, the Send method invocation becomes equivalent to the Get or Post method.

The Send method is the only way to carry out HTTP methods other than GET or POST.

Syntax

%httpResponse = httpRequest:Send( [[Port=] string], [[Cancel=] number], - [CertificateCheck= certificateChecker], - [CheckKeepAliveCertificate= boolean], - Method= name)

Syntax terms

%httpresponse A reference to the HttpResponse object instantiated and returned by this Send method.
httpRequest An instantiated HttpRequest object that contains the request (its methods were used to create the request).
Port A string expression that identifies a previously defined CLSOCK port. The default value is the MASTER port, if any is defined. However, if you do not specify a value and no MASTER port is defined, the request is canceled.

This is an optional and name-allowed parameter. If you specify a value, you may (but don't have to) specify the parameter name, Port (case not important).

Cancel A numeric expression that controls whether the request is cancelled if a communication/socket error occurs. If zero, the request is not cancelled on these errors. If non-zero, the request is cancelled (though a message is still issued). If not specified, it defaults to 1 (cancel). See "Usage notes," below, for further discussion of error handling.

This is an optional and name-allowed parameter. If you specify a value, you may (but don't have to) specify the parameter name, Cancel (case not important) if you want.

CertificateCheck This optional (name required) argument invokes an SSL certificate request from the server at the time of the method call.

The argument value (certificateChecker) must be a function, presumably local, with this method template:

Function (String):methname Is Boolean

When a connection is established, the passed function is called with the certificate (binary content, ASN.1 encoded, copied to a Longstring) as its method object.

  • If the function returns a True, the request is completed.
  • If the function returns a False, the connection is closed and HttpRequest returns a null. In this case, the request is canceled unless the Cancel argument setting prevents it.
For a CertificateCheck function example, see Examples for the Get method.
CheckKeepAliveCertificate This optional, name required, argument controls how frequently a specified CertificateCheck function is invoked for a an HTTP keep-alive connection. If False, the default, the certificateChecker function is called only when the physical connection is first established and not for every HTTP request on that connection. If set to True, the CertificateCheck method is called for every request, keep-alive or not.
Method Method is both a required and name required parameter that specifies the quoted name of any HTTP method type (for example, 'GET', 'PUT', 'MOVE'). The parameter name, Method, is not case sensitive, but it must be supplied. The type name must be less than or equal to 16 characters, all uppercase.

Usage notes

  • Although you may specify the Method parameter before the optional parameters, you receive a compilation error if you do so without also specifying the optional parameter names with the optional parameters.
  • For information about error handling, see the Get function "Usage notes".
  • If the ports associated with the sockets in the HTTP request are not using SSL, and the CertificateCheck argument is specified, the certificateChecker function does not get called.
  • To send an HTTP GET or POST, you can also use the Get method or the Post method, respectively.

Examples

Send statements with argument variations are shown below:

%resp = %req:send(method='DELETE') %resp = %req:send('CLPORT', method='DELETE') %resp = %req:send(method='POST', port='CLPORT', cancel=1)

See also