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Version: v19

Session

Session objects are returned by the Session command when scalable sessions are enabled in your project. The Session object is automatically created and maintained by the 4D web server to control the session of a web client (e.g. a browser). This object provides the web developer with an interface to the user session, allowing to manage privileges, store contextual data, share information between processes, and launch session-related preemptive processes.

For detailed information about the session implementation, please refer to the web server Sessions section.

Summary

.clearPrivileges()    removes all the privileges associated to the session
.expirationDate : Text    the expiration date and time of the session cookie
.hasPrivilege( privilege : Text ) : Boolean    returns True if the privilege is associated to the session, and False otherwise
.idleTimeout : Integer    the inactivity session timeout (in minutes), after which the session is automatically closed by 4D
.isGuest() : Boolean    returns True if the session is a Guest session (i.e. it has no privileges)
.setPrivileges( privilege : Text )
.setPrivileges( privileges : Collection )
.setPrivileges( settings : Object )
    associates the privilege(s) defined in the parameter to the session
.storage : Object    a shared object that can be used to store information available to all requests of the web client
.userName : Text    the user name associated to the session

Session

History
VersionChanges
v18 R6Added

Session : 4D.Session

ParameterTypeDescription
Result4D.Session<-Session object

Description

The Session command returns the Session object corresponding to the current scalable user web session.

This command only works when scalable sessions are enabled. It returns Null when sessions are disabled or when legacy sessions are used.

When scalable sessions are enabled, the Session object is available from any web processes in the following contexts:

  • On Web Authentication, On Web Connection, and On REST Authentication database methods,
  • ORDA Data Model Class functions called with REST requests,
  • code processed through 4D tags in semi-dynamic pages (4DTEXT, 4DHTML, 4DEVAL, 4DSCRIPT/, 4DCODE)
  • project methods with the "Available through 4D tags and URLs (4DACTION...)" attribute and called through 4DACTION/ urls.

Example

You have defined the action_Session method with attribute "Available through 4D tags and URLs". You call the method by entering the following URL in your browser:

IP:port/4DACTION/action_Session
  //action_Session method
Case of
:(Session#Null)
If(Session.hasPrivilege("WebAdmin")) //calling the hasPrivilege function
WEB SEND TEXT("4DACTION --> Session is WebAdmin")
Else
WEB SEND TEXT("4DACTION --> Session is not WebAdmin")
End if
Else
WEB SEND TEXT("4DACTION --> Sesion is null")
End case

.clearPrivileges()

History
VersionChanges
v18 R6Added

.clearPrivileges()

ParameterTypeDescription
Does not require any parameters

Description

The .clearPrivileges() function removes all the privileges associated to the session. As a result, the session automatically becomes a Guest session.

Example

//Invalidate a session
var $isGuest : Boolean

Session.clearPrivileges()
$isGuest:=Session.isGuest() //$isGuest is True

.expirationDate

History
VersionChanges
v18 R6Added

.expirationDate : Text

Description

The .expirationDate property contains the expiration date and time of the session cookie. The value is expressed as text in the ISO 8601 format: YYYY-MM-DDTHH:MM:SS.mmmZ.

This property is read-only. It is automatically recomputed if the .idleTimeout property value is modified.

Example

var $expiration : Text
$expiration:=Session.expirationDate //eg "2021-11-05T17:10:42Z"

.hasPrivilege()

History
VersionChanges
v18 R6Added

.hasPrivilege( privilege : Text ) : Boolean

ParameterTypeDescription
privilegeText<-Name of the privilege to verify
ResultBoolean<-True if session has privilege, False otherwise

Description

The .hasPrivilege() function returns True if the privilege is associated to the session, and False otherwise.

Example

You want to check if the "WebAdmin" privilege is associated to the session:

If (Session.hasPrivilege("WebAdmin"))
//Access is granted, do nothing
Else
//Display an authentication page

End if

.idleTimeout

History
VersionChanges
v18 R6Added

.idleTimeout : Integer

Description

The .idleTimeout property contains the inactivity session timeout (in minutes), after which the session is automatically closed by 4D.

If this property is not set, the default value is 60 (1h).

When this property is set, the .expirationDate property is updated accordingly.

The value cannot be less than 60: if a lower value is set, the timeout is raised up to 60.

This property is read write.

Example

If (Session.isGuest())
// A Guest session will close after 60 minutes of inactivity
Session.idleTimeout:=60
Else
// Other sessions will close after 120 minutes of inactivity
Session.idleTimeout:=120
End if

.isGuest()

History
VersionChanges
v18 R6Added

.isGuest() : Boolean

ParameterTypeDescription
ResultBoolean<-True if session is a Guest one, False otherwise

Description

The .isGuest() function returns True if the session is a Guest session (i.e. it has no privileges).

Example

In the On Web Connection database method:

If (Session.isGuest())
//Do something for Guest user
End if

.setPrivileges()

History
VersionChanges
v18 R6Added

.setPrivileges( privilege : Text )
.setPrivileges( privileges : Collection )
.setPrivileges( settings : Object )

ParameterTypeDescription
privilegeText->Privilege name
privilegesCollection->Collection of privilege names
settingsObject->Object with a "privileges" property (string or collection)

Description

The .setPrivileges() function associates the privilege(s) defined in the parameter to the session.

  • In the privilege parameter, pass a string containing a privilege name (or several comma-separated privilege names).

  • In the privileges parameter, pass a collection of strings containing privilege names.

  • In the settings parameter, pass an object containing the following properties:

PropertyTypeDescription
privilegesText or Collection
  • String containing a privilege name, or
  • Collection of strings containing privilege names
  • userNameTextUser name to associate to the session (optional)

    If the privileges property contains an invalid privilege name, it is ignored.

    In the current implementation, only the "WebAdmin" privilege is available.

    By default when no privilege is associated to the session, the session is a Guest session.

    The userName property is available at session object level (read-only).

    Example

    In a custom authentication method, you set the "WebAdmin" privilege to the user:

    var $userOK : Boolean

    ... //Authenticate the user

    If ($userOK) //The user has been approved
    var $info : Object
    $info:=New object()
    $info.privileges:=New collection("WebAdmin")
    Session.setPrivileges($info)
    End if

    .storage

    History
    VersionChanges
    v18 R6Added

    .storage : Object

    Description

    The .storage property contains a shared object that can be used to store information available to all requests of the web client.

    When a Session object is created, the .storage property is empty. Since it is a shared object, this property will be available in the Storage object of the server.

    Like the Storage object of the server, the .storage property is always "single": adding a shared object or a shared collection to .storage does not create a shared group.

    This property is read only itself but it returns a read-write object.

    Example

    You want to store the client IP in the .storage property. You can write in the On Web Authentication database method:

    If (Session.storage.clientIP=Null) //first access
    Use (Session.storage)
    Session.storage.clientIP:=New shared object("value"; $clientIP)
    End use
    End if

    .userName

    History
    VersionChanges
    v18 R6Added

    .userName : Text

    Description

    The .userName property contains the user name associated to the session. You can use it to identify the user within your code.

    This property is an empty string by default. It can be set using the privileges property of the setPrivileges() function.

    This property is read only.