[yocto] Idea for bbappend / layer organization and naming convention

[Bruce Ashfield]

On 08/18/2017 10:46 AM, Gunnar Andersson wrote:
> 
> On Mon, 2017-08-14 at 23:02 -0400, Bruce Ashfield wrote:
>> On 2017-08-14 3:36 PM, Gunnar Andersson wrote:
>>>
>>> Yocto community,
>>>
>>> Triggered by the previous email request to yocto@ about best practices
>>> for layer organization I'm finally firing off this email for (hopefully)
>>> some feedback on an idea we first kicked around, discussed for rough
>>> consensus and then decided to implement in the Yocto based GDP project
>>> [1].  You can see it as a trial, anything can be changed, but so far so
>>> good...
>>>
>>> We adopted a somewhat novel (but actually not really unique, see inside)
>>> naming convention [2] for all modifications to components that belong to
>>> other layers.
>>>
>>
>> I've been using a similar naming/sorting mechanism in layers that
>> I maintain for several years now.
> 
> Great.  Is it similar, or /exactly/ like this?  I'm only asking because I
> think it would be useful to have some written down rules and if there are
> additional tweaks that will improve this proposal, I'd like to hear them.
> 

Exactly. The layer name and recipe-* structure is nested in a layer
that is carrying bbappends. That way there's zero confusion about where
the main recipe can be found.

Bruce

> I suspected it might actually be somewhat of a common practice.
> 
>> When you have a single layer that is carrying bbappends to many other
>> layers, I find that it really helps keep everything separated and aids
>> finding the original recipe.
> 
> Yes, that is the idea.
> 
>>
>> (that being said, recent work with layer index, etc, make it
>> easier to locate the original recipe and any bbappends .. but that
>> doesn't preclude keeping things organized in a layer).
> 
> ... but I didn't get any more feedback than yours, so I'll just leave it
> where it is for now.  Maybe this is not something the other Yocto community
> cares about, or similar practices are actually done in practice, but not
> written down.  Or maybe everyone is OK with the state of mixing .bb and
> .bbappend files within the layers...
> 
> So far I think the initial experience on our side is positive.  It's
> something that needs to be looked after a bit (we have a few mistakes to
> fix).  But since some directories will only have .bb files, and others only
> .bbappend files, it's therefore easy to script a warning system for anything
> that is out of place.
> 
> Best Regards
> - Gunnar
> 
>> Cheers,
>>
>> Bruce
>>
> [trimmed]
> 
>>> -- 
>>> Gunnar Andersson <gandersson at genivi.org>
>>> Development Lead
>>> GENIVI Alliance
>>>
>>> [1] https://github.com/GENIVI/genivi-dev-platform
>>> [2] Naming strategy for bitbake extension layers:			
>>> https://at.projects.genivi.org/wiki/x/w4Xk
> 
>