Re: [tosca] Propagation of default values in inheritance hierarchies: standpoint for TOSCA v1.2/v1.3?

[Tal Liron <tliron@redhat.com>]

Well, not quite an inheritance issue but a "propagation" issue. I guess the question is whether by encapsulating one data type inside another the default properties would also be included. I'm sure we all agree that the answer is yes.

It's not immediately obvious, so I would recommend adding an explanation in the spec, possibly with an example.

On Sun, Aug 16, 2020 at 4:08 PM Chris Lauwers <lauwers@ubicity.com> wrote:

Iâm not sure there is a âpropagationâ (or inheritance) issue here. This seems to be a very straightforward example where (as Gabor states) the resulting value is indeed 1.

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Chris

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From: tosca@lists.oasis-open.org <tosca@lists.oasis-open.org> On Behalf Of Tal Liron
Sent: Saturday, August 15, 2020 12:44 PM
To: Marton, Gabor (Nokia - HU/Budapest) <gabor.marton@nokia.com>
Cc: tosca@lists.oasis-open.org; Nemeth, Denes (Nokia - HU/Budapest) <denes.nemeth@nokia.com>; Nguyenphu, Thinh (Nokia - US/Dallas) <thinh.nguyenphu@nokia.com>
Subject: Re: [tosca] Propagation of default values in inheritance hierarchies: standpoint for TOSCA v1.2/v1.3?

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As you point out, the spec wasn't entirely clear up to 1.3. I think somewhere it does point out that all keywords are inherited, but I can't find it right now...

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In any case, I think all popular current implementations inherit the "default" keyword, as it does seem to be natural and intended.

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On Fri, Aug 14, 2020 at 1:30 PM Marton, Gabor (Nokia - HU/Budapest) <gabor.marton@nokia.com> wrote:

Dear TOSCA Experts,

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in TOSCA v1.2 and v1.3, is the below example node template valid i.e. does its (required) property complex_1.example_1.property_1 have the value value_1?

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data_types:

 provider.datatypes.Example:

ÂÂÂ derived_from: tosca.datatypes.Root

ÂÂÂ properties:

ÂÂÂÂÂ property_1:

ÂÂÂÂÂÂÂ type: string

ÂÂÂÂÂÂÂ default: value_1

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 provider.datatypes.Complex:

ÂÂÂ derived_from: tosca.datatypes.Root

ÂÂÂ properties:

ÂÂÂÂÂ example_1:

ÂÂÂÂÂÂÂ type: provider.datatypes.Example

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node_types:

 provider.nodes.Example:

ÂÂÂ derived_from: tosca.nodes.Root

ÂÂÂ properties:

ÂÂÂÂÂ complex_1:

ÂÂÂÂÂÂÂ type: provider.datatypes.Complex

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topology_template:

 node_templates:

ÂÂÂ example:

ÂÂÂÂÂ type: provider.nodes.Example

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Propagation of default values is not explicitly covered by TOSCA v1.2/v1.3.

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In the TOSCA v2.0 draft, I can see one sentence that makes me answer the above question affirmatively: âdefault: a new definition is unrestricted and will overwrite the one inherited from the property definition in the parent entity type definition" (4.4.5.5 Refinement rules).

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Greetings,

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GÃbor

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