Sessions Module

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This XQuery Module can only be called from users with Admin permissions. It contains functions for accessing and modifying all registered server-side sessions. This module is mainly useful in the context of Web Applications.

Conventions[edit]

  • The module will be available if the basex-api library is found in the classpath. This is the case if you use one of the complete distributions of BaseX (zip, exe, war).
  • All functions and errors are assigned of the http://basex.org/modules/sessions namespace, which is statically bound to the sessions prefix.
  • If any of the functions is called outside the servlet context, basex:http is raised.
  • If a specified session id is not found, not-found is raised.
  • As sessions are side-effecting operations, all functions are flagged as nondeterministic. As a result, some query optimizations will be suppressed.

Functions[edit]

sessions:ids[edit]

Signature
sessions:ids() as xs:string*
Summary Returns the IDs of all registered sessions.

sessions:created[edit]

Signature
sessions:created(
  $id  as xs:string
) as xs:dateTime
Summary Returns the creation time of the session specified by $id.

sessions:accessed[edit]

Signature
sessions:accessed(
  $id  as xs:string
) as xs:dateTime
Summary Returns the last access time of the session specified by $id.

sessions:names[edit]

Signature
sessions:names(
  $id  as xs:string
) as xs:string*
Summary Returns the names of all attributes bound to the session specified by $id.

sessions:get[edit]

Signature
sessions:get(
  $id       as xs:string,
  $name     as xs:string,
  $default  as item()*    := ()
) as item()*
Summary Returns the value of an attribute with the specified $name from the session with the specified $id. If the attribute is unknown, an empty sequence or the optionally specified $default value will be returned instead.

sessions:set[edit]

Signature
sessions:set(
  $id     as xs:string,
  $name   as xs:string,
  $value  as item()*
) as empty-sequence()
Summary Returns the specified value to the attribute with the specified $name from the session with the specified $id.

sessions:delete[edit]

Signature
sessions:delete(
  $id    as xs:string,
  $name  as xs:string
) as empty-sequence()
Summary Deletes an attribute with the specified $name from the session with the specified $id.

sessions:close[edit]

Signature
sessions:close(
  $id  as xs:string
) as empty-sequence()
Summary Unregisters the session specified by $id.

Errors[edit]

Code Description
not-found The specified session is not available.

Changelog[edit]

Version 9.3
  • Updated: sessions:get: Values that have no XQuery type will be returned as strings.
Version 9.0
  • Updated: error codes updated; errors now use the module namespace
Version 8.4
  • Updated: Allow sequences as session values.

This module was introduced with Version 7.5.