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

• The basex-api package must be included in the classpath. This is always the case if you use one of the complete distributions (zip, exe, war) of BaseX.
• All functions are assigned to the http://basex.org/modules/session namespace. The module must be imported in the query prolog:

import module namespace session = "http://basex.org/modules/session";
...

• 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.
• If any of the functions is called outside the servlet context, the error BXSE0003: is raised.
• As sessions are side-effecting operations, all functions are flagged as non-deterministic. This means that the functions will not be reordered by the compiler.

Functions

session:id

Signatures	session:id() as xs:string
Summary	Returns the session ID of a servlet request.
Examples	Running the server-side XQuery file id.xq via http://localhost:8984/id.xq: import module namespace session = "http://basex.org/modules/session"; 'Session ID: ' || session:id()

session:created

Signatures	session:created() as xs:dateTime
Summary	Returns the creation time of a session.

session:accessed

Signatures	session:accessed() as xs:dateTime
Summary	Returns the last access time of a session.

session:names

Signatures	session:names() as xs:string*
Summary	Returns the names of all variables bound to the current session.
Examples	Running the server-side XQuery file names.xq via http://localhost:8984/names.xq: import module namespace session = "http://basex.org/modules/session"; session:names() ! element variable { . }

session:get

Signatures	session:get($key as xs:string) as item()* session:get($key as xs:string, $default as item()*) as item()*
Summary	Returns the value of a variable bound to the current session. If the key is unknown, an empty sequence or the optionally specified default value is returned instead.
Errors	BXSE0002: the value of a session variable 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 ' || $key || ': ' || session:get($key)

session:set

Signatures	session:set($key as xs:string, $value as item()*) as empty-sequence()
Summary	Binds the specified key/value pair to a session.
Errors	BXSE0001: a function item was specified as value of a session variable.
Examples	Running the server-side XQuery file set.xq via http://localhost:8984/set.xq?key=user&value=john: import module namespace session = "http://basex.org/modules/session"; session:set($key, $value), 'Variable was set.'

session:delete

Signatures	session:delete($key as xs:string) as empty-sequence()
Summary	Deletes a session variable.
Examples	Running the server-side XQuery file delete.xq via http://localhost:8984/delete.xq?key=user: import module namespace session = "http://basex.org/modules/session"; session:delete($key), 'Variable 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.
BXSE0003	A function was called outside the servlet context.

Changelog

Version 8.0

• Updated: Allow sequences as session values.

This module was introduced with Version 7.5.