[patch, netjsonconfig]: importing backends from other modules

[Edoardo Putti]

Hello everyone,

it's been a long time since 2017 GSOC but I keep reading the digest from the project.

Recently I had some time to experiment with python packaging and this is the result applied to netjsonconfig [0].

This change would help integrating with custom backend that the community has been experimenting on that did not get merged upstream [1], [2], [3], [4] or simply

make writing a backend simpler without having to touch the original netjsonconfig code.

I still don't know if this is the correct way to do this "find backends dinamically" thing so if there are more experienced python packagers please chime in.

edoput

[0]: https://github.com/openwisp/netjsonconfig/pull/106

[1]: https://github.com/openwisp/netjsonconfig/pull/92

[2]: https://github.com/openwisp/netjsonconfig/pull/91

[3]: https://groups.google.com/forum/#!searchin/openwisp/custom$20backend|sort:date/openwisp/BqHQQ2_TmxE/rXOLB93yBAAJ

[4]: https://groups.google.com/forum/#!searchin/openwisp/virtual$20machine|sort:date/openwisp/fOzhr1gQ-Zc/qnZX3zcWAwAJ

[Federico Capoano]

Hi Edoardo,

thanks for the patch.

I'm not 100% sure I fully understood this patch in practice.

In the pull request you cite a `setup.py` example, but I don't understand if that would be the `setup.py` of a python module using netjsonconfig or that should be the setup.py of netjsonconfig itself.

Could you give a full example?

If it's what I think it is, it will most likely need a bit of documentation to help users understand how this feature works and how it can be used.

Federico

[Edoardo Putti]

The patch is from a package using netjsonconfig.

Take AirOS as an example, I would create a project, netjsonconfig-airos, import netjsonconfig for the base classes, write my backend + templates

and then write the entry_point attribute in my setup.py to reference my backend class.

Then when using netjsonconfig if I want to use the netjsonconfig-airos backend it's just a pip install away.

I'll make an example backend soon to provide more reference to how this works

[Federico Capoano]

Sounds great. Could you add some documentation regarding this feature?

You could, for example, start a page called "extending.rst" and explain this concept there including an example.

It will be a great chance for me as well to add a few lines on how to create a new backend.

Federico

[Edoardo Putti]

The example backend is available here https://github.com/edoput/example_backend

I'll add a page documenting this feature soon

[eg...@innovationgarage.no]

I greatly support this patch as it's The Right Way To Do it<tm> :P Please merge :)

[Edoardo Putti]

I've added a page title `create_your_backend` to the documentation. Rigth now is in docs/source/backend folder, let me know if this should be elsewhere

[Edoardo Putti]

I finally found some time to squash the commits and make every check green so this feature could be safely merged.

I don't know if anyone has tested it before the merge but if you encounter any issue I'm happy to help troubleshooting

Have a nice Sunday

edoput

[Federico Capoano]

I merged, thank you Edoardo!

I'd be happy if some of you guys could test the development version and send any useful feedback.

Fed