The reasons you explained you wanted the layer made me think you only needed datamapper. Be simpler rather than complex. Explain again why you need the layer, please? Remember YAGNI.
Blog: http://random8.zenunit.com/ Learn rails: http://sensei.zenunit.com/ On 05/02/2009, at 5:28 AM, sbrocher <sbroc...@gmail.com> wrote: > > Hi Julian, > > Thanks for your answer. I've seen Datamapper before. However, the way > I understand it, Datamapper is pretty much just a replacement for > ActiveRecord, so I don't see how it would add the extra layer of > abstraction I'm searching for... Did I miss something here? > > Thanks > Seb > > On Feb 3, 9:33 pm, Julian Leviston <jul...@coretech.net.au> wrote: >> Datamapper. >> >> Blog:http://random8.zenunit.com/ >> Learn rails:http://sensei.zenunit.com/ >> >> On 04/02/2009, at 1:59 PM, sbrocher <sbroc...@gmail.com> wrote: >> >> >> >> >> >>> Hi, >> >>> I've implemented a few big RoR apps. I do have some good experience >>> building large systems in many different languages and platforms >>> but I >>> don't consider myself a RoR guru, so I'd like you experts comment on >>> my thoughts. >> >>> I'd like to divide a large system (app) into several functional, >>> high- >>> level sub-systems. These are higher level than rails Models, and >>> provide APIs that implement business logic around functional groups. >>> Examples of these are billing manager, security manager (accounts, >>> privileges, roles, etc), inventory manager, manufacturing manager, >>> and >>> such (of course, these are just examples, but you get the point). >> >>> These high-level sub-systems may be implemented as servers (think >>> SOAP / REST / XML-RPC / ...), or just plain Ruby classes. Some of >>> these sub-systems implement integrations with other systems, for >>> example, a credit card gateway, an accounting system, Fedex, you >>> name >>> it. Some of the sub-systems may be just proxies to a system >>> implemented on some other technology. >> >>> The user interface (views) would not have access to any of the >>> Models. >>> They just present and / or grab data that is prepared for them / >>> pushed back to the controllers as local variables / arrays / hash >>> tables that don't reflect an actual Model. >> >>> The controllers do not have access to Models either. Instead, they >>> call methods from the high-level functional sub-system APIs. >> >>> The Models implement lower-level business logic related to how to >>> the >>> information is stored and retrieved from the database, the pertinent >>> validations, associations, etc. but do not implement high-level >>> business logic such as "how do I bill Joe for a specific event that >>> results in the combination of many other parameters and variables >>> that >>> at the end come from diverse fields on many different tables on the >>> underlying database structure". >> >>> The high-level sub-systems all share the same database and therefore >>> same data model and only communicate with each other via their APIs, >>> and can access all Models directly. >> >>> In other words, this would work more or less as a new layer in >>> between >>> the MVC pattern: >> >>> view <-> controller <-> high-level sub-system <-> models <-> >>> database >> >>> The idea is to build the app in a more robust / less coupled way >>> where >>> I can exchange parts of the app by different technologies and other >>> applications in the future without having to recode a bunch of >>> things. >>> For example, the security subsystem could one day be replaced by an >>> AAA server and then the subsystem would be re-implemented to call >>> the >>> AAA server (to replace its own original implementation), however the >>> rest of the app would continue to use the same API calls to the >>> security subsystem and so the change is isolated from the rest of >>> the >>> app. >> >>> The problem with this is, I'd loose many of the RoR goodness, such >>> as >>> form helpers, easy models validation thrown back to the interface, >>> etc. >> >>> Am I missing some Ruby language construct or RoR framework construct >>> that would enable me to implement this kind of design on an easier >>> manner? Should I instead be thinking of many RoR applications >>> somehow >>> talking to each other? >> >>> I really like RoR but I'm starting to find myself on a tough >>> situation >>> dealing with evolving mid-to-large systems (think 50+ database >>> tables >>> and 8+ sub-systems). I need to come up with a pattern that would >>> force >>> me to implement and design code that works and is maintainable on a >>> long-term vision, however I'm not sure if this is because I don't >>> know >>> the 100% of what the language and framework has to offer, or if I am >>> just using it the wrong way (or both? :-). >> >>> Comments? >> >>> Thanks, >>> Seb- Hide quoted text - >> >> - Show quoted text - > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. 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