172 OWA_COOKIE

The OWA_COOKIE package provides an interface for sending and retrieving HTTP cookies from the client's browser.

The chapter contains the following topics:


Using OWA_COOKIE


Overview

Cookies are opaque strings sent to the browser to maintain state between HTTP calls. State can be maintained throughout the client's sessions, or longer if an expiration date is included. The system date is calculated with reference to the information specified in the OWA_CUSTOM package.


Types

This data type contains cookie name-value pairs. Since the HTTP standard allows cookie names to be overloaded (that is, multiple values can be associated with the same cookie name), there is a PL/SQL RECORD holding all values associated with a given cookie name.

TYPE vc_arr IS TABLE OF VARCHAR2(4000) INDEX BY BINARY_INTEGER.

TYPE COOKIE IS RECORD (
   name           VARCHAR2(4000),
   vals           vc_arr,
   num_vals       INTEGER);

Rules and Limits

All HTTP headers must be in English and the ASCII character set. If the headers are generated from the database, verify they are created in the English language.


Summary of OWA_COOKIE Subprograms

Table 172-1 OWA_COOKIE Package Subprograms

Subprogram Description

GET Function

Gets the value of the specified cookie

GET_ALL Procedure

Gets all cookie name-value pairs

REMOVE Procedure

Removes the specified cookie

SEND procedure

Generates a "Set-Cookie" line in the HTTP header



GET Function

This function returns the values associated with the specified cookie. The values are returned in a OWA_COOKIE.COOKIE DATA TYPE.

Syntax

OWA_COOKIE.GET(
    name           IN       VARCHAR2) 
  RETURN COOKIE;

Parameters

Table 172-2 GET Procedure Parameters

Parameter Description

name

The name of the cookie.


Return Values

OWA_COOKIE.COOKIE DATA TYPE.


GET_ALL Procedure

This procedure returns all cookie names and their values from the client's browser. The values appear in the order in which they were sent from the browser.

Syntax

OWA_COOKIE.GET_ALL(
   names          OUT      vc_arr,
   vals           OUT      vc_arr,
   num_vals       OUT      INTEGER);

Parameters

Table 172-3 GET_ALL Procedure Parameters

Parameter Description

names

The names of the cookies.

vals

The values of the cookies.

num_vals

The number of cookie-value pairs.



REMOVE Procedure

This procedure forces a cookie to expire immediately by setting the "expires" field of a Set-Cookie line in the HTTP header to "01-Jan-1990". This procedure must be called within the context of an HTTP header.

Syntax

OWA_COOKIE.REMOVE(
   name           IN       VARCHAR2,
   val            IN       VARCHAR2,
   path           IN       VARCHAR2   DEFAULT NULL);

Parameters

Table 172-4 REMOVE Procedure Parameters

Parameter Description

name

The name of the cookie to expire.

val

The value of the cookie.

path

[Currently unused]



SEND procedure

This procedure generates a Set-Cookie line, which transmits a cookie to the client. This procedure must occur in the context of an HTTP header.

Syntax

OWA_COOKIE.SEND(
   name           in       varchar2,
   value          in       varchar2,
   expires        in       date       DEFAULT NULL,
   path           in       varchar2   DEFAULT NULL,
   domain         in       varchar2   DEFAULT NULL,
   secure         in       varchar2   DEFAULT NULL);

Parameters

Table 172-5 SEND Procedure Parameters

Parameter Description

name

The name of the cookie.

value

The value of the cookie.

expires

The date at which the cookie will expire

path

The value for the path field.

domain

The value for the domain field.

secure

If the value of this parameter is not NULL, the "secure" field is added to the line.