[Cosmo-dev] Cosmo WebUI Service Layer

[Ted Leung]

On Mar 5, 2007, at 4:18 PM, Bobby Rullo wrote:

>
> On Mar 5, 2007, at 3:31 PM, Ted Leung wrote:
>
>> On Mar 5, 2007, at 3:10 PM, Travis Vachon wrote:
>>
>>>
>>> On Mar 5, 2007, at 1:30 PM, Bobby Rullo wrote:
>>>
>>>>> Example: retry
>>>>> There will, in the future...
>>>>
>>>> I would also like to see a way for the owner conduit and  
>>>> subscription conduit (and all other conduits which require  
>>>> login) to prompt the user to re-login if they've timed out and  
>>>> then automatically retry the request.
>>>>
>>> Agreed. I'm not sure this should go in the service layer, though.  
>>> I don't really like the idea of mixing ui code into the service  
>>> layer. Throwing an exception that ui code can handle, or that  
>>> could be handled by some useful error handling module, seems more  
>>> appropriate.
>>
>> Error handling topic/notification?
>
> I don't think it would work in this case, Ted. The topic would  
> fire, but the original caller would already get a callback saying  
> it failed.
>
> Now, if we decided to make EVERYTHING async and totally break apis  
> that we have we could do this. You would have "TryToSave" topic  
> which could get picked up by the service layer, and it could try  
> and save, and post a topic if it failed, and something else could  
> pick up that, log the user in, post the "TryToSave" message again....
>
> But I don't think we are going this route. It felt too heavy and  
> would require (too) much re-writing of existing code.

Ok

>>
>>>
>>>
>>>> The MDC api is likely to be more stable, and I'd rather not have  
>>>> to make the UI dev manually inject conduits into newly created  
>>>> items/collections.
>>> This will never be necessary, as the conduit injection will be  
>>> done at the conduit level. Essentially, items will inherit the  
>>> Conduit they were fetched over. I'll add  this to the proposal.
>>
>> So the Conduit will update a field in items that it fetches?
>>
>
> What do you mean? If you mean that a conduit will stick it self in  
> any item it fecthes, than yes.

Yes, that's what I meant.

>
>>>>
>>>> Also, what do we do about "new" items? Does the conduit become  
>>>> like an item factory - "var item = conduit.newItem()" ?
>>>>
>>> This is a model question, really. Unless we want to significantly  
>>> change how the code currently works, I think sticking with the  
>>> "create an item and use saveItem to make it appear on the server"  
>>> idiom. It would probably make sense to have a method like
>>>
>>> Collection.newItem(){create an Item that inherits my Conduit}
>>
>> Is there another proposal for the model, then?
>
> Well, the service layer and the model are seeming to become intwined.

Well, the model is using the service, which you'd expect.  Is the  
service also using the model (less good)?

Ted