[cpp-pistache] Fix not processing enums in cpp-pistache-server

[mpreu]

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Description of the PR

Fixes #1317

Defining a reusable enum as a component schema results in an empty
class. Following changes were made:

• activate 'postProcessModelsEnum' in 'AbstractCppCodegen'
• modify model templates for the 'cpp-pistache-server' project

As 'postProcessModelsEnum' is now available in the 'AbstactCppCodegen'
the 'enumVars' variables are now available in mustache templates for all
cpp based code generators.

As the 'AbstractCppCodegen' was touched all cpp based samples
are updated.

@ravinikam (2017/07) @stkrwork (2017/07) @fvarose (2017/11) @etherealjoy (2018/02) @MartinDelille (2018/03) @sebymiano

[etherealjoy]

@mpreu
Nice PR. Thanks a lot.

[etherealjoy]

I tried this PR and it looks good, need some minor adaptation
I used the Spec from #1317 and removed the anyOf, because it is buggy until we get the new PR #1360 for anyOf support integrated.

• So in the mustache some change needs to be done to detect if it is an enum, because an enum is now created as a class and to serialize it . toJson and fromJson needs to handle it as well during serialization.
• The enum description is missing in the enumeration declaration
• Also need to check the case of integer.

[wing328]

@mpreu Closing this due to no update. Please let us know if you still want to proceed with the change by resolving the merge conflicts

[mfyuce]

Hi,
Thanks for the PR.

What is it that needed to fix/reopen/merge this PR? I will help if needed.

Thanks a lot.

[wing328]

@mfyuce can you please cherry-pick the commits and file a new one instead? Let me know if you need help on that.

[mfyuce]

Thanks @wing328 for the info. Let me work on that. Will inform.

[mfyuce]

Hi @wing328,

Have sent a PR at #8886. Hope it will be usefull.

All the best.

PS: Just a problem (may be not, currently evaluating), if the property in the api file has an "anyOf" field containing the enum value, the class generated (let us name "AnEnumClass") does not contain the enums, but a different class ("AnEnumClass_anyOf") has the enum variable. The problem is "AnEnumClass" does not reference "AnEnumClass_anyOf" in anyway. I have checked generated qt server server codes, the same problem is there also. What do you think? Is it a problem? I can inform if any problem after integrating it to our project at netas