Session Module
This XQuery Module contains functions for accessing and modifying server-side session information. This module is mainly useful in the context of Web Applications.
Conventions
As sessions are side-effecting operations, all functions in this module are flagged as non-deterministic. This means that the evaluation order of the functions will not be influenced by the compiler.
All functions are assigned to the http://basex.org/modules/session namespace, which must be dynamically imported. In this documentation, the namespace is bound to the session prefix. Errors are assigned to the http://basex.org/errors namespace, which is statically bound to the bxerr prefix.
Functions
session:id
| Signatures | session:id() as xs:string
|
| Summary | Returns the session ID of a servlet request. |
| Examples | Running a RESTXQ function via http://localhost:8984/restxq/id:
module namespace test = 'http://basex.org/examples/test';
import module namespace session = "http://basex.org/modules/session";
declare %restxq:path("/id") function test:id() {
'Session ID: ' || session:id()
};
|
session:attributes
| Signatures | session:attributes() as xs:string*
|
| Summary | Returns the names of all attributes bound to the current session. |
| Examples | Running the server-side XQuery file attributes.xq via http://localhost:8984/attributes.xq:
import module namespace session = "http://basex.org/modules/session";
session:attributes() ! element attribute { . }
|
session:attribute
| Signatures | session:attribute($key as xs:string) as xs:string?session:attribute($key as xs:string, $default as xs:string) as xs:string
|
| Summary | Returns the value of an attribute bound to the current session. If the attribute does not exist, an empty sequence or the optionally specified default value is returned instead. |
| Errors | BXSE0002: the value of a session attribute could not be retrieved.
|
| Examples | Running the server-side XQuery file get.xq via http://localhost:8984/get.xq?key=user:
import module namespace session = "http://basex.org/modules/session"; 'Value of ' || $key || ': ' || session:attribute($key) |
session:update-attribute
| Signatures | session:update-attribute($key as xs:string, $value as xs:string) as empty-sequence()
|
| Summary | Assigns a value to a session attribute. |
| Errors | BXSE0001: a function item was specified as value of a session attribute.
|
| Examples | Running the server-side XQuery file set.xq via http://localhost:8984/set.xq?key=user&value=john:
import module namespace session = "http://basex.org/modules/session"; session:update-attribute($key, $value), 'Attribute was set.' |
session:delete-attribute
| Signatures | session:delete-attribute($key as xs:string) as empty-sequence()
|
| Summary | Deletes a session attribute. |
| Errors | BXSE0001: a function item was specified as value of a session attribute.
|
| Examples | Running the server-side XQuery file delete.xq via http://localhost:8984/delete.xq?key=user:
import module namespace session = "http://basex.org/modules/session"; session:delete-attribute($key), 'Attribute was deleted.' |
session:close
| Signatures | session:close() as empty-sequence()
|
| Summary | Unregisters a session and all data associated with it. |
Errors
| Code | Description |
|---|---|
BXSE0001
|
A function item was specified as value of a session attribute. |
BXSE0002
|
An error occurred while retrieving the value of a session attribute. |
Changelog
This module was introduced with Version 7.5.
