Configure relationship change notification

A relationship exists between two managed objects. By default, when a relationship changes (when it is created, updated, or deleted), the managed objects on either side of the relationship are not notified of that change. This means that the state of each object with respect to that relationship field is not recalculated until the object is read. This default behavior improves performance, especially in the case where many objects are affected by a single relationship change.

For roles, a special kind of relationship, change notification is configured by default. The purpose of this default configuration is to notify managed users when any of the relationships that link users, roles, and assignments are manipulated. For more information about relationship change notification in the specific case of managed roles, see Roles and relationship change notification.

To change the default configuration, or to set up notification for other relationship changes, use the notify* properties in the relationship definition, as described in this section.

A relationship exists between an origin object and a referenced object. These terms reflect which managed object is specified in the URL (for example managed/user/psmith), and which object is referenced by the relationship (_ref*) properties. For more information about the relationship properties, see Create a relationship between two objects.

In the previous example, a PUT on managed/user/psmith with "manager" : {_ref : "managed/user/bjensen"}, causes managed/user/psmith to be the origin object, and managed/user/bjensen to be the referenced object for that relationship, as shown in the following illustration:

Illustration shows the origin and referenced objects in a relationship

Figure 1. Relationship Objects

Note that for the reverse relationship (a PUT on managed/user/bjensen with "reports" : [{_ref = "managed/user/psmith"}]) managed/user/bjensen would be the origin object, and managed/user/psmith would be the referenced object.

By default, when a relationship changes, neither the origin object nor the referenced object is notified of the change. So, with the PUT on managed/user/psmith with "manager" : {_ref : "managed/user/bjensen"}, neither psmith’s object nor bjensen’s object is notified.

Auditing is not tied to relationship change notification and is always triggered when a relationship changes. Therefore, relationship changes are audited, regardless of the notify and notifySelf properties.

To configure relationship change notification, set the notify and notifySelf properties in your managed object schema. These properties specify whether objects that reference relationships are notified of a relationship change:

notifySelf

Notifies the origin object of the relationship change.

In our example, if the manager definition includes "notifySelf" : true, and if the relationship is changed through a URL that references psmith, then psmith’s object would be notified of the change. For example, for a CREATE, UPDATE or DELETE request on the psmith/manager, psmith would be notified, but the managed object referenced by this relationship (bjensen) would not be notified.

If the relationship were manipulated through a request to bjensen/reports, then bjensen would only be notified if the reports relationship specified "notifySelf" : true.

notify

Notifies the referenced object of the relationship change. Set this property on the resourceCollection of the relationship property.

In our example, assume that the manager definition has a resourceCollection with a path of managed/user, and that this object specifies "notify" : true. If the relationship changes through a CREATE, UPDATE, or DELETE on the URL psmith/manager, then the reference object (managed/user/bjensen) would be notified of the change to the relationship.

notifyRelationships

This property controls the propagation of notifications out of a managed object when one of its properties changes through an update or patch, or when that object receives a notification through one of these fields.

The notifyRelationships property takes an array of relationships as a value; for example, "notifyRelationships" : ["relationship1", "relationship2"]. The relationships specified here are fields defined on the managed object type (which might itself be a relationship).

Notifications are propagated according to the recipient’snotifyRelationships configuration. If a managed object type is notified of a change through one if its relationship fields, the notification is done according to the configuration of the recipient object. To illustrate, look at the attributes property in the default managed/assignment object:

{
    "name" : "assignment",
    "schema" : {
        ...
        "properties" : {
            ...
            "attributes" : {
                "description" : "The attributes operated on by this assignment.",
                "title" : "Assignment Attributes",
                ...
                "notifyRelationships" : ["roles"]
            },
...

This configuration means that if an assignment is updated or patched, and the assignment’s attributes change in some way, all the roles connected to that assignment are notified. Because the role managed object has "notifyRelationships" : ["members"] defined on its assignments field, the notification that originated from the change to the assignment attribute is propagated to the connected roles, and then out to the members of those roles.

So, the role is notified through its assignments field because an attribute in the assignment changed. This notification is propagated out of the members field because the role definition has "notifyRelationships" : ["members"] on its assignments field.

By default, roles, assignments, and members use relationship change notification to ensure that relationship changes are accurately provisioned.

For example, the default user object includes a roles property with notifySelf set to true:

{
   "name" : "user",
   ...
   "schema" : {
       ...
       "properties" : {
           ...
           "roles" : {
               "description" : "Provisioning Roles",
               ...
               "items" : {
                   "type" : "relationship",
                   ...
                   "reverseRelationship" : true,
                   "reversePropertyName" : "members",
                   "notifySelf" : true,
                   ...
               }
...

In this case, notifySelf indicates the origin or user object. If any changes are made to a relationship referencing a role through a URL that includes a user, the user will be notified of the change. For example, if there is a CREATE on managed/user/psmith/roles which specifies a set of references to existing roles, user psmith will be notified of the change.

Similarly, the role object includes a members property. That property includes the following schema definition:

{
    "name" : "role",
    ...
    "schema" : {
        ...
        "properties" : {
            ...
            "members" : {
                ...
                "items" : {
                    "type" : "relationship",
                    ...
                    "properties" : {
                        ...
                        "resourceCollection" : [
                            {
                                "notify" : true,
                                "path" : "managed/user",
                                "label" : "User",
                                ...
                            }
                        ]
                    }
...

Notice the "notify" : true setting on the resourceCollection. This setting indicates that if the relationship is created, updated, or deleted through a URL that references that role, all objects in that resource collection (in this case, managed/user objects) that are identified as members of that role must be notified of the change.

To notify an object at the end of a relationship that the relationship has changed (using the notify property), the relationship must be bidirectional ("reverseRelationship" : true).

When an object is notified of a relationship state change (create, delete, or update), part of that notification process involves calculating the changed object state with respect to the changed relationship field. For example, if a managed user is notified that a role has been created, the user object calculates its base state, and the state of its roles field, before and after the new role was created. This before and after state is then reconciled. An object that is referenced by a forward (unidirectional) relationship does not have a field that references that relationship; the object is "pointed-to", but does not "point-back". Because this object cannot calculate its before and after state with respect to the relationship field, it cannot be notified.

Similarly, relationships that are notified of changes to the objects that reference them must be bidirectional relationships.

If you configure relationship change notification on a unidirectional relationship, IDM throws an exception.
You cannot configure relationship change notification in the admin UI; you must update the managed object configuration directly.

IDM 7.2.2

Configure relationship change notification