Session Module
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This XQuery Module contains functions for accessing and modifying server-side session information. This module is mainly useful in the context of Web Applications.
Contents
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 and errors 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"; ...
- If any of the functions is called outside the servlet context, the error
basex:http
: is raised. - As sessions are side-effecting operations, all functions are flagged as non-deterministic. As a result, 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($name as xs:string) as item()* session:get($name as xs:string, $default as item()*) as item()*
|
Summary | Returns the value of $name bound to the current session. If the specified variable is unknown, an empty sequence or the optionally specified default value is returned instead.
|
Errors | get : 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($name as xs:string, $value as item()*) as empty-sequence()
|
Summary | Binds the specified name/value pair to a session. |
Errors | set : a function item was specified as value of a session variable.
|
Examples | Running the server-side XQuery file set.xq via http://localhost:8984/set.xq?key=user&value=john :
import module namespace session = "http://basex.org/modules/session"; session:set($key, $value), 'Variable was set.' |
session:delete
Signatures | session:delete($name as xs:string) as empty-sequence()
|
Summary | Deletes a session value bound to $name .
|
Examples | Running the server-side XQuery file delete.xq via http://localhost:8984/delete.xq?key=user :
import module namespace session = "http://basex.org/modules/session"; session:delete($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 |
---|---|
get
|
The stored attribute is no XQuery value. |
set
|
Function items cannot be stored. |
Changelog
- Version 9.0
- Updated: error codes updated; errors now use the module namespace
- Version 8.0
- Updated: Allow sequences as session values.
This module was introduced with Version 7.5.