ALPS, which stands for Application-Level Profile Semantics, is a format created by Mike Amundsen for describing the semantics, or meaning, of an application's data and actions in a simple and reusable way. It's similar to HTML microformats in its simplicity and is designed to be used across different media types and environments[2].
This post is composed from output by the perplexity.ai bot and is part of a series of posts exploring AI chatbot responses.
In essence, ALPS is a way to define the "what" of a service without getting into the "how." It doesn't specify details like URLs, HTTP methods, or status codes. Instead, it focuses on describing the operations (like read
, write
, submit
, approve
) and data elements (like familyName
, givenName
) that make up a service[4]. This makes ALPS a useful tool for the design phase of API development, as it can be used to create a clear picture of the service's capabilities that is independent of the implementation details.
ALPS documents can be represented in XML or JSON format and contain descriptors that provide a machine-readable collection of identifying strings and their human-readable descriptions[5]. These descriptors can then be used as source material for design-time formats like RAML, WADL, Swagger, or for client-side frameworks like Ember.js or Angular[3].
ALPS (Application-Level Profile Semantics) format is different from other API description formats in several ways:
1. Simplicity: ALPS is similar in complexity to HTML microformats, making it easier to understand and work with compared to other formats like RAML, WSDL, or Swagger[4][3].
2. Focus on Semantics: ALPS describes the operations and data elements of a service without getting into the specific implementation details like URLs, HTTP methods, or status codes[3][7]. This makes it a useful tool for designing the "what" of a service, independent of the "how."
3. Independence from Implementation: ALPS is not a runtime format like HTML or HAL, and it's not a design-time format like RAML or Swagger[3]. Instead, it's a profile format for describing the bounded context of a service, which can be used as source material for both design-time and client-side frameworks[3].
4. Reusability: The same ALPS description document can be used by many ALPS-compliant servers, as it doesn't include URLs or other implementation-specific details[5][3]. This increases the reusability of profile documents across media types[5].
5. Format Agnostic: ALPS can be represented in either XML, JSON or YAML format, making it adaptable to different environments and media types[5].
In summary, ALPS is a simple, focused, and reusable format for defining the semantics of a service's operations and data elements, without being tied to specific implementation details or formats. This makes it a valuable tool for designing and understanding the core capabilities of a service across various environments and frameworks[3][7].
Citations:
[1] https://nordicapis.com/review-of-alps/
[2] https://datatracker.ietf.org/doc/draft-amundsen-richardson-foster-alps/
[3] https://apievangelist.com/2015/03/10/what-is-alps/
[4] https://mamund.substack.com/p/alps-unified-utility
[5] http://alps.io/spec/drafts/draft-01.html
[6] https://groups.google.com/g/api-craft/c/mSFq__019ik
[7] https://www.oreilly.com/library/view/design-and-build/9781680508123/f_0040.xhtml
ALPS has been made infinitely more usable due to the work of Akihito Koriyama and the ASD project (https://alps-asd.github.io/manuals/1.0/en/index.html)