measuring rest
DESCRIPTION
Slides from my talk at restfest 2011.TRANSCRIPT
Measuring REST
Subbu Allamarajuhttp://www.subbu.org
http://twitter.com/sallamar
My (Im)Maturity
Level 1: What is REST?Level 2: Wow! … What? … Aha!Level 3: Explain, rationalizeLevel 4: Build stuff
Hypermedia and Media Types
How to measure REST?
What to measure?
Performance – network performance, user perceived performance, and network efficiency
ScalabilitySimplicity Modifiability – evolvability, extensibility, customizability, configurability, and reusability
VisibilityPortabilityReliability
REST Constraints
100 % REST?
• But “glory” is not a systemic quality.
• Glory is not measurable• Does not lead to $$$
Show me 100% RESTful apps
Is REST a hoax then?
Question #1: Is this a marketing or messaging problem?
Question #2: Can you prove that sum(constraints) leads to
sum(qualities)?
Hand-waveReason out and rationalize in the abstract
Nah, we need to put some engineering back into software
Question #3: Can you prove that any given constraint leads to
any quality?
Hand-waveAdvocate: “Make judicious tradeoffs”
But how do I know if I’m making judicious tradeoffs?
Step #1: Agree on a set of qualities that matter for your app
Ex:• Performance• Ease of use • Adoption
Roy’s list is not the super-set
Step #2: Contextualize the qualities into scenarios
• Performance• Serve a photo in “t” msec• Process “n” photos per hour
• Ease of use • A developer should be able to build
a client app in 30 minutes• Adoption
• Must gain “y00” developers in 3 months after launch
Step #3: Prioritize qualities and scenarios
• Adoption• Must gain “y00” developers in 3
months after launch• Performance
• Serve a photo in “t” msec• Process “n” photos per hour
• Ease of use • A developer should be able to build
a client app in 30 minutes
Step #4: Pick solutions among alternatives that you think meet
the scenarios
• Adoption• Must gain “y00” developers in 3
months after launch• Performance
• Serve a photo in “t” msec• Process “n” photos per hour
• Ease of use • A developer should be able to build
a client app in 30 minutes
What should you measure?
$$$$$$,$$$
$$$,$$$,$$$
Make the case for REST constraints based on specific scenarios and priorities