A service MAY allow entities to request the most recent N items by using the 'max_items' attribute. When max_items is used, implementations SHOULD return the N most recent (as opposed to the N oldest) items. (Note: A future version of this specification may recommend the use of &xep0059; instead of the 'max_items' attribute.)
+A service MAY allow entities to request the most recent N items by using the 'max_items' attribute. When max_items is used, implementations SHOULD return the N most recent (as opposed to the N oldest) items. (Note: A future version of this specification may recommend the use of XEP-0059 instead of the 'max_items' attribute.)
The service would then return that specific item, if available.
There are several reasons why the items retrieval request might fail:
@@ -3335,7 +3337,7 @@ And by opposing end them?Implementations of pubsub MAY deliver event notifications only when the subscriber is online. In these cases, the option may be a node configuration option as shown in the examples above. To facilitate this, the pubsub service needs to subscribe to the subscriber's presence and check the subscriber's current presence information before sending any event notifications (as described in RFC 3921). Presence subscriptions MUST be based on the subscribed JID.
+If the pubsub service supports presence-based delivery and a node is configured to enable such delivery, the service MAY offer a value of "iq" for the "pubsub#notification_type" node configuration option. If this value is chosen, the service shall deliver notifications in XMPP IQ stanzas instead of in XMPP message stanzas. Because IQ stanzas are addressed to full JIDs &LOCALFULL;, if the service does not know the full JID of a given subscriber then it MAY send notifications to the bare JID &LOCALBARE; of the subscriber via the usual message stanza, or MAY not send a notification at all. The IQ stanza containing a notification shall be of type "set", and in accordance with the semantics of the IQ stanza defined in RFC 3920 the recipient MUST return either an IQ stanza of type "result" or an IQ stanza of type "error". An example follows
+If a service understands the semantics for a particular payload type and an entity's subscription is so configured (via the "pubsub#include_body" option), the service SHOULD include an appropriate XMPP &BODY; child element along with the payloads it sends in event notifications for a given node, where the body's XML character data summarizes or represents the information contained in the payload (this enables clients that do not understand the payload format to present the appropriate information to an end user). For example, the Atom <summary/> element (see RFC 4287) could be mapped to the XMPP &BODY; element. A service MUST NOT provide the "pubsub#include_body" subscription option for a node if it does not have a defined way to transform part or all of the payload format into a sensible message body. A node owner MAY define an XSLT for transforming the payload format into a message body, via the "pubsub#body_xslt" node configuration option. This XSLT is applied by the pubsub service after receiving a publish request and before sending the appropriate notifications, not by the client before sending a publish request.
-If the service does not understand the semantics for a particular payload type, it MAY include a <body/> child whose XML character data informs the subscriber that the message contains an event notification (e.g., text such as "This message contains an event notification" would be appropriate).
+If a service understands the semantics for a particular payload type and an entity's subscription is so configured (by the "pubsub#include_body" subscription option to true), the service SHOULD include an appropriate XMPP &BODY; child element along with the payloads it sends in event notifications for a given node, where the body's XML character data summarizes or represents the information contained in the payload (this enables clients that do not understand the payload format to present the appropriate information to an end user). For example, the Atom <summary/> element (see RFC 4287) could be mapped to the XMPP &BODY; element. A service MUST NOT provide the "pubsub#include_body" subscription option for a node if it does not have a defined way to transform part or all of the payload format into a sensible message body. A node owner MAY define an XSLT for transforming the payload format into a message body, via the "pubsub#body_xslt" node configuration option. This XSLT is applied by the pubsub service after receiving a publish request and before sending the appropriate notifications, not by the client before sending a publish request.
+If the service does not understand the semantics for a particular payload type and therefore cannot transform the payload into a human-readable message body, it SHOULD NOT include a <body/> child.
+If a subscriber has multiple subscriptions to the same node, where some of the SubIDs have include_body set to true and others have include_body set to false, the service SHOULD include a body with all notifications.