RE: [soa-blueprints] Anti-Blueprints

There are some SOA anti-patterns that will be common to general software but there will also be specifics to SOA (like don’t start with process). I’ve no idea who said it but I recall reading once a phrase something like “IT is 5% what to do, and 95% what not to do”. Having anti-patterns is at this stage almost more valuable than proper patterns as they act as breaks on development expense that would be pointless. I know of a few clients I’ve saved money for by pointing out what is wrong who are now taking the time to move towards a more controlled blueprints type approach.

Not only does IT need the “This Way” signs, we also need “There be dragons”.

Steve

From: Matt MacKenzie [mailto:mattm@adobe.com]
Sent: 25 October 2005 22:35
To: Miko Matsumura; soa-blueprints@lists.oasis-open.org
Subject: RE: [soa-blueprints] Anti-Blueprints

Why is it valuable to define an “anti-pattern” such as the one discussed here? Doesn’t this anti pattern apply to pretty much all programming models? It looks like y’all are fishing here.

Just my CAD$0.02…

-matt

From: Miko Matsumura [mailto:mmatsumura@infravio.com]
Sent: Tuesday, October 25, 2005 4:10 PM
To: soa-blueprints@lists.oasis-open.org
Subject: RE: [soa-blueprints] Anti-Blueprints

Good feedback Duane.

This is a good topic, thanks for introducing it, Steve.

The number of services *is* a quantitative measure, but perhaps not a very helpful one? =)

I'm pretty sure there's an antipattern here, and I think perhaps there could be some kind of way to assess this. I think another variable in this mix is the extent to which the registry repository in question can help with respect to discovery and classification as well as governance. The thing that worries me is when I see people assuming that fine grained (object level) services will be reused, when the reality is that OO didnt generate that much reuse from even the guy in the next cubicle, let alone across the company or across the planet.

I think this is less of a gross number of services antipattern so much as a coarse-grained vs fine-grained antipattern...

Best,

Miko

From: Duane Nickull [mailto:dnickull@adobe.com]
Sent: Tuesday, October 25, 2005 12:57 PM
To: soa-blueprints@lists.oasis-open.org
Subject: RE: [soa-blueprints] Anti-Blueprints

I disagree with this anti-pattern.

I am not sure that the number of services is really a quantitative measure of SOA. A grid computing cluster administrator may be able to rationalize such behavior, although it may seem absurd in other areas such as Amazon deploying a service for each book it carries vs. deploying one service that allows the consumer to parameterize the book title.

Perhaps a better measure would be the development of some test criteria to ascertain whether a contemplated service is a good candidate for repurposing beyond a small number of consumers. This should be based on alignment with LOB and presumably different implementers will have different criteria for quantifying such.

Duane

From: Miko Matsumura [mailto:mmatsumura@infravio.com]
Sent: Tuesday, October 25, 2005 12:41 PM
To: marchadr@wellsfargo.com; steve.g.jones@capgemini.com; soa-blueprints@lists.oasis-open.org
Subject: RE: [soa-blueprints] Anti-Blueprints

I just added a "microservice" antipattern where programmers put 10000000 WSDLs into a registry just because their IDE lets them do so.

Miko

From: marchadr@wellsfargo.com [mailto:marchadr@wellsfargo.com]
Sent: Tuesday, October 25, 2005 11:54 AM
To: steve.g.jones@capgemini.com; soa-blueprints@lists.oasis-open.org
Subject: RE: [soa-blueprints] Anti-Blueprints

Steve,

Good idea. I put up the first drafts of them at: http://blueprints.jot.com/WikiHome/SOA+Anti-Patterns/SOA%20Anti-Patterns

Let me know if I correctly eloborated and named them for you.

Thanks,

Dan

-----Original Message-----
From: Jones, Steve G [mailto:steve.g.jones@capgemini.com]
Sent: Tuesday, October 25, 2005 11:21 AM
To: soa-blueprints@lists.oasis-open.org
Subject: [soa-blueprints] Anti-Blueprints

The SOA Blueprints will lay down a “best practice” set of guidelines and templates for delivering SOA. This will definitely be a positive thing and help expand and firm up people’s understanding of SOA. One thing that the group states that it will do is define standards and guidelines, does this mean that allied to our blueprints we must also consider the “anti-blueprints” (analogous to anti-patterns) that must be avoided. So for instance focusing on process over service (bad), only thinking of web services (bad) etc etc. Defining the blueprints give guidance towards success criteria, but should we also give guidance on failure criteria for acceptance of a system as being “SOA”.



Not sure whether this should be in the TC as its laying down best practice, and not to increase the already large workload… but it needs to be somewhere.

My top 5 are

1)       If you’ve started with an enterprise “best practice” process map you are NEVER going to be SOA and 90% probability your system will be inflexible or fail.

2)       Web Service point to point is STILL point to point, doing a bad practice in XML doesn’t make it better

3)       Splitting into two separate tiers of Service and Process with separate rules and governance results in divergent solutions

4)       Creating “business” services based on the belief that IT understands the business results in services that meet neither IT nor business goals

5)       Building your own proprietary XML-RPC stack to give yourself “control“

The last could still be SOA from one perspective, but I’ve yet to see it done well when the driver was a belief that its better done in house than using standards. When we get the official Wiki it could be something to document via that route.

Steve

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