Thanks everybody. It seems like we've converged on a similar approach. 

Do you guys keep your domain models all in repos at the root of your 

Also, right now my api call ends with a (Cmd ModelUponSuccess), with that 
ModelUponSuccess belonging to the child page that uses the model returned 
(where it is also stored, for now, though I was thinking about refactoring 
them out into top level repos; hence the question above. But I need to also 
issue a (Cmd AndBumpThatAuthToken) upon a successful api call. Do I 
the ModelUponSuccess message from the caller to a message type in the api 
itself, so that it can issue a Cmd.batch list of commands that are all of 
the message type of the api module itself? 

[AppRoot] -> [UsersPage] --> ask api for users, and upon success, 
1. send the UsersFetchSuccess message (attaching the users); so far so 
good, but then also I need to...
2. replace the token by sending the BumpToken message at the root level of 
the app.

Getting a little late here, so hopefully that's still coherent. Thanks 
again everybody. I'm pretty new to the language and really appreciate the 

On Wednesday, October 12, 2016 at 10:48:18 PM UTC+9, Peter Damoc wrote:

> On Wed, Oct 12, 2016 at 4:13 PM, Fa Qing < <javascript:>
> > wrote:
>> I'm just curious how everybody approaches their API service layer in 
>> complex applications.
>> Right now, I have a shared API module that I call from various 
>> elements/pages/components/children... in a pretty flat architecture. That 
>> module abstracts out the common request composition, etc.
> This is also what I had in my app: an API module that exposes a Cmd 
> producing interface to the rest of the app. 
> All API callers provide:
> 1. `success` and  `failure` message constructors
> 2. the auth_token (if needed)
> 3. the rest of the data required for the request
> The extraction from the header and injection in the header can be 
> abstracted in some custom `get` and `post` functions. 
> Right now I have an Api.sendJson call that returns a task
> This sounds like a good approach (similar to the custom `post` that I 
> mentioned earlier) but I would not expose this to the rest of the app. 
> I would use something like this internally to do the job. 
> In using my API module, I would always use only functions that produce Cmd 
> (I avoid using the tasks). 
> To give you an example. I had a User object that had a list of Companies. 
> The list is saved a set of IDs and to get the final Elm object I had to 
> first get the user data and then go through each of the IDs in the 
> Companies field and request the Company data for that company. 
> All these details are not the concern of the rest of the program. The rest 
> of the program just gets the final User with a list of Companies, nicely 
> wrapped in a message. 
> Internally to API, there are various functions that help with constructing 
> the final Task that first fetches the user and then fetches the rest of the 
> data but these tasks are not exposed outside the module. 
> If the database storage changes or I decide on another strategy, the rest 
> of the app is isolated from these changes because it talks in the higher 
> language of the API not in the lower language of the Http that the API uses 
> to implement the functionality. 
> -- 
> There is NO FATE, we are the creators.
> blog:

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