[Paper Review] Feeds as Query Result Serializations

Erik Wilde|ArXiv.org|Nov 11, 2009

Peer-to-Peer Network Technologies14 references3 citations

TL;DR

This paper proposes rethinking feeds as serialized query results rather than static data streams, enabling dynamic, flexible, and extensible data access across diverse Web services. By modeling feeds as query result serializations, the approach supports advanced query capabilities—such as filtering, cross-entry, and cross-feed queries—while leveraging existing standards like Atom and OpenSearch for discovery and extensibility, significantly broadening feeds' applicability beyond traditional use cases like blogs and news feeds.

ABSTRACT

Many Web-based data sources and services are available as feeds, a model that provides consumers with a loosely coupled way of interacting with providers. The current feed model is limited in its capabilities, however. Though it is simple to implement and scales well, it cannot be transferred to a wider range of application scenarios. This paper conceptualizes feeds as a way to serialize query results, describes the current hardcoded query semantics of such a perspective, and surveys the ways in which extensions of this hardcoded model have been proposed or implemented. Our generalized view of feeds as query result serializations has implications for the applicability of feeds as a generic Web service for any collection that is providing access to individual information items. As one interesting and compelling class of applications, we describe a simple way in which a query-based approach to feeds can be used to support location-based services.

Motivation & Objective

• To address the limitations of current feed models, which are hardcoded and lack extensibility for diverse application scenarios.
• To explore how feeds can be generalized as a standardized, query-based mechanism for accessing collections of information items.
• To enable a loosely coupled, RESTful interaction model between feed providers and consumers using declarative query semantics.
• To demonstrate the feasibility and benefits of this model through concrete use cases, particularly in location-based services.

Proposed method

• Conceptualizes feeds as serialized results of queries over collections, treating each feed as a representation of a query result set.
• Analyzes existing feed standards (RSS, Atom) and extensions (AtomPub, OpenSearch, FIQL) to identify query capabilities and discoverability mechanisms.
• Proposes a generalized query model that supports feed queries, extended queries, collection queries, cross-entry queries, and cross-feed queries.
• Introduces the concept of feedsets—aggregations of feeds that enable cross-feed query processing.
• Leverages existing Web standards for query discovery, such as link relations in feeds to advertise query capabilities.
• Proposes a distributed query processing model where filtering and query operations are pushed upstream to optimize bandwidth and performance.

Experimental results

Research questions

• RQ1 How can feeds be re-conceptualized as serialized query results to extend their applicability beyond static data streams?
• RQ2 What are the key limitations of current feed models in supporting dynamic, flexible, and extensible data access?
• RQ3 How can query capabilities (e.g., filtering, joining across feeds) be discovered and exposed in a standardized, interoperable way?
• RQ4 What architectural patterns and standards (e.g., OpenSearch, FIQL) can enable scalable, distributed query processing over feeds?
• RQ5 How can this model be applied to real-world scenarios such as location-based services?

Key findings

• Feeds can be effectively modeled as serialized query results, enabling a declarative, RESTful interaction model between providers and consumers.
• The current feed model is limited by hardcoded query semantics, but extending it to support dynamic queries significantly increases its expressiveness and reusability.
• Query discovery mechanisms such as link relations in feeds (e.g., for paging and archiving) can be extended to expose richer query capabilities using standards like OpenSearch and FIQL.
• Cross-feed queries require aggregation intermediaries, and processing should be pushed upstream to optimize performance and reduce downstream load.
• The model enables spontaneous, configuration-free interaction between clients and providers, as clients can discover query features directly from the feed.
• The approach is compatible with existing Web security and access control mechanisms, allowing integration with standard Web protocols.