[almighty] Potential cyclic import issue in core.

[Thomas Mäder]

Hi Pranav,


On 10/12/2016 04:36 AM, Pranav Gore wrote:
>  When we say a system-layer., is it a bunch of related packages ? Or a 
> layer is a package.
No, a layer is more abstract: for example the API layer would take care 
of handling json requests via htttp, the database layer stores things in 
the db. The characteristics of a layered approach is that you can only 
call things from layers "beneath" you, not above you. The package 
structure must follow this layering to some extent in order for build 
system to know what to compile first.
Structuring a system in layers is a design choice we are free to make or 
not. Layering imposes certain restrictions on the code you write. The 
reason you would want those restrictions is to separate the system into 
parts with controlled interfaces. This reduces coupling between the 
layers. Code with uncontrolled coupling everywhere is what is generally 
referred to as "spaghettig code". It gets hard to change and to 
understand the possible consequences.

> @Thomas, is this (#110) 
> <https://github.com/almighty/almighty-core/issues/110> existing 
> architecture issue for the same ? If yes, I will update the same.
Issue #110 talks about something related, but slightly different: the 
structs we use for storage with gorm are adapted to the purpose of 
storage. The structs generated from our goa design are adapted for use 
in the API. The structures in both layers are not what we would come up 
if we tried to design our data model free of constraints. #110 raises 
the issue whether we need that "ideal" layer between the API and the db.

/Thomas
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://listman.redhat.com/archives/almighty-public/attachments/20161012/08067fc4/attachment.htm>