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:keys
| Signatures
|
session:keys() as xs:string*
|
| Summary
|
Returns the names of all variables bound to the current session.
|
| Examples
|
Running the server-side XQuery file keys.xq via http://localhost:8984/keys.xq:
import module namespace session = "http://basex.org/modules/session";
session:keys() ! element variable { . }
|
session:get
| Signatures
|
session:get($key as xs:string) as xs:string?
session:get($key as xs:string, $default as xs:string) as xs:string
|
| Summary
|
Returns the value of a variable bound to the current session. If the variable does not exist, 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, $value as xs:string) as empty-sequence()
|
| Summary
|
Assigns a value to a session variable.
|
| Errors
|
BXSE0001: a function item was specified as value of a session variable.
|
| Examples
|
Running the server-side XQuery file set.xq via http://localhost:8984/set.xq?key=user&value=john:
import module namespace session = "http://basex.org/modules/session";
session:set($key, $value), 'Variable was set.'
|
session:delete
| Signatures
|
session:delete($key as xs:string) as empty-sequence()
|
| Summary
|
Deletes a session variable.
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| Errors
|
BXSE0001: a function item was specified as value of a session variable.
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| 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.
|
Changelog
This module was introduced with Version 7.5.
