Using query language for provider and subscriber registrations

• US 6,275,957 B1
• Filed: 10/20/1998
• Issued: 08/14/2001
• Est. Priority Date: 09/21/1998
• Status: Expired due to Term

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Novik, Lev, Hudis, Irena, McCollum, Raymond
• Primary Examiner(s): Beausoleil, Robert
• Assistant Examiner(s): BADERMAN, SCOTT T
• Application Number:
  US09/175,592
• Time in Patent Office: 1,029 Days
• Field of Search: 714/48-57, 714/39, 707/3, 707/6, 709/318-321
• US Class Current: 714/39
• CPC Class Codes: G06F 16/24568 Data stream processing; Continuous queries

Abstract

Systems and methods for reporting the occurrence of events in a computer system to event subscriber software. A computer system includes a central repository wherein event subscribers register the types or classes of events for which they require notification and event providers register the types or classes of events they are capable of detecting and for which they will provide notifications. The registrations, both by providers and subscribers, are made according to a standardized hierarchical classification of event classes and are preferably expressed in the form of queries. The computer system also includes an event-filtering component that receives notification of the occurrence of events, filters the events, and reports selected events to the subscriber software. The event-filtering component can expose standardized interfaces to the event providers that report events and to the subscriber software to which events are reported. Filtering can be facilitated by event-filtering definitions written in a query language and associated with the subscriber software. The definitions are processed in the context of an object-oriented, hierarchical classification of event classes that comprehend any possible events that can be reported by the event providers. When reported events satisfy one or more query-based filtering definitions, the events are passed to the appropriate subscriber software. Otherwise, the events are discarded. Events can be filtered and grouped according to the time of their occurrence. Filtering can be further simplified by registering event-reporting definitions defining the scope of events to be reported by particular event providers.

Claims

1. In a computer system having one or more event providers capable of detecting the occurrence of certain conditions or events in said computer system or the environment of said computer system and having one or more event subscribers requiring notification of certain conditions or events in said computer system or the environment of said computer system, a method for providing an interface between said event providers and said event subscribers comprising:

the step of defining a hierarchical classification of events that comprehend a set of possible conditions and events;

the step of providing to the computer system an event filtering and reporting component;

the step of registering with said event filtering and reporting component (a) an event provider definition associated with each event provider, wherein the event provider definition is expressed in terms of said hierarchical classification of events and specifies the conditions or events of which such event provider will provide notification to the event filtering and reporting component and (b) an event subscriber definition associated with each said event subscriber, wherein the event subscriber definition is expressed in terms of said hierarchical classification of events and specifies the conditions or events for which such event subscriber requests notification from the event filtering and reporting component;

the step of filtering, by the event filtering and reporting component, conditions or events reported by the event providers to the event filtering and reporting component; and

the step of notifying each said event subscriber of only those conditions or events that satisfy the event subscriber definition associated with that event subscriber.

2. The method of claim 1 wherein the registering step further comprises:

the step of generating, for each event provider that registers with the event filtering and reporting component, a query tree; and

the step of storing the query tree for each registered event provider in the event filtering and reporting component.

3. The method of claim 2 further comprising, after the registering step:

the step of detecting, by the event providers registered with the event filtering and reporting component, the occurrence of a condition or event in the computer or the environment of the computer that satisfies the event provider definition for that event provider; and

the step of sending notification of the occurrence of said condition or event from the event provider to the event filtering and reporting component.

4. The method of claim 3 wherein the filtering step comprises:

the step of receiving, by the event filtering and reporting component, an event notification sent by an event provider;

the step of retrieving, by the event filtering and reporting component, the query tree associated with the event provider from which said event notification is detected; and

the step of determining, by the event filtering and reporting component, whether the event satisfies the event subscriber definition of any one or more of the event subscribers registered with the event filtering and reporting component by traversing the query tree for the event provider from which the event notification was received.

5. In a computer system having one or more event providers capable of detecting the occurrence of certain conditions or events in said computer system or the environment of said computer system and having one or more event subscribers requiring notification of certain conditions or events in said computer system or the environment of said computer system, a system for providing an interface between said event providers and said event subscribers comprising:

means for defining a hierarchical classification of events that comprehend a set of possible conditions and events;

means, logically connected to said event providers and said event subscribers, for filtering conditions or events detected by said event providers and for reporting certain conditions or events to said event subscribers; and

means for registering with said event filtering and reporting means (a) an event provider definition associated with each event provider, wherein the event provider definition is expressed in terms of said hierarchical classification of events and specifies the conditions or events of which such event provider will provide notification to the event filtering and reporting means and (b) an event subscriber definition associated with each said event subscriber, wherein the event subscriber definition is expressed in terms of said hierarchical classification of events and specifies the conditions or events for which such event subscriber requests notification from the event filtering and reporting means, and

wherein said event filtering and reporting means filters the conditions or events reported by the event providers and notifies each said event subscriber of only those conditions or events that satisfy the event subscriber definition associated with that event subscriber.

6. The system of claim 5 wherein the registering means comprises:

means for generating, for each event provider that registers with the event filtering and reporting means, a query tree; and

means for storing the query tree for each registered event provider in the event filtering and reporting component.

7. The system of claim 6 further comprising:

means for detecting, by the event providers registered with the event filtering and reporting means, the occurrence of a condition or event in the computer or the environment of the computer that satisfies the event provider definition for that event provider; and

means for sending notification of the occurrence of said condition or event from the event provider to the event filtering and reporting means.

8. The system of claim 7 wherein the event filtering and reporting means comprises:

means for receiving an event notification sent by an event provider;

means for retrieving the query tree associated with the event provider from which said event notification is detected; and

means for determining whether the event satisfies the event subscriber definition of any one or more of the event subscribers registered with the event filtering and reporting component by traversing the query tree for the event provider from which the event notification was received.

9. An article of manufacture for use in a computer system having a CPU, one or more event providers capable of detecting the occurrence of certain conditions or events in said computer system or the environment of said computer system, and having one or more event subscribers requiring notification of certain conditions or events in said computer system or the environment of said computer system, the article of manufacture comprising:

program storage means, accessible by the CPU, for storing and providing to a CPU program code means, said program code means comprising;

means for defining a hierarchical classification of events that comprehend a set of possible conditions and events;

means, logically connected to said event providers and said event subscribers, for filtering conditions or events detected by said event providers and for reporting certain conditions or events to said event subscribers; and

means for registering with said event filtering and reporting means (a) an event provider definition associated with each event provider, wherein the event provider definition is expressed in terms of said hierarchical classification of events and specifies the conditions or events of which such event provider will provide notification to the event filtering and reporting means and (b) an event subscriber definition associated with each said event subscriber, wherein the event subscriber definition is expressed in terms of said hierarchical classification of events and specifies the conditions or events for which such event subscriber requests notification from the event filtering and reporting means, and

wherein said event filtering and reporting means filters the conditions or events reported by the event providers and notifies each said event subscriber of only those conditions or events that satisfy the event subscriber definition associated with that event subscriber.

10. The article of manufacture of claim 9 wherein the registering means comprises:

means for generating, for each event provider that registers with the event filtering and reporting means, a query tree; and

means for storing the query tree for each registered event provider in a location accessible to the event filtering and reporting means.

11. The article of manufacture of claim 10 further comprising:

means for detecting, by the event providers registered with the event filtering and reporting means, the occurrence of a condition or event in the computer or the environment of the computer that satisfies the event provider definition for that event provider; and

means for sending notification of the occurrence of said condition or event from the event provider to the event filtering and reporting means.

12. The article of manufacture of claim 11 wherein the event filtering and reporting means further comprises:

means for receiving an event notification sent by an event provider;

means for retrieving the query tree associated with the event provider from which said event notification is detected; and

means for determining whether the event satisfies the event subscriber definition of any one or more of the event subscribers registered with the event filtering and reporting means by traversing the query tree for the event provider from which the event notification was received.