[feature] Added device groups #203

[pandafy]

A group can be specified for devices, i.e. DeviceGroup.
DeviceGroup contains metadata about group of deivces in form of JSON.
JSONSchema can be set systemwide for validation of entered metadata.

Added REST API endpoint for listing, creating and retrieving DeviceGroups.

Closes #203

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• Add a DeviceGroup or Group model and admin (maybe we should call it DeviceGroup to avoid confusion with other models that are called Group, like django's auth.Group model), the model shall have fields like (organization, using OrgMixin), name, description, meta_data, created, modified.
• Add an optional "group" field to Device, the field should be a ForeignKey to DeviceGroup.
• Emit a signal when the group field of a device is change and document the new signal.
• Add the group relation to the DeviceAdmin class, using the django admin autocomplete feature.
• Add a setting which allows to define the schema for DeviceGroup.meta_data and document it.
• Ensure meta_data field is JSON formatted field which will leverage the work we did with JSON schema to show the UI, by default the schema will be empty and allow any property so the user can add what they need.
• Both adminstrators and operators user types shall be able to edit config.Group.
• Add group REST API list and detail endpoints, eg: /api/v1/controller/group/, /api/v1/controller/group/{id}/, authentication and permission checks should be consistent with the REST API endpoints added recently in [feature] REST API for main controller features #379 #386 and the ones being added in [api] Rest API for PKI app #455.

[coveralls]

Coverage decreased (-0.1%) to 98.702% when pulling 702be03 on issues/203-device-group-model into 030fc9d on master.

[nemesifier]

Great progress @pandafy! Here's a first code-only review.

[nemesifier]

There's one failing test.

[nemesifier]

The screenshot shows "Configuration menu" and "Advanced mode" buttons, which shouldn't be included, is that screenshot outdated or are those buttons not disabled? It should be possible to remove them, see how it's done in credentials for reference.

[nemesifier]

Does the metadata without any schema defined look weird to you as well?

Device group detail API URL

Getting the detail of a group returns me the groups, wierd..

Also, there's no DELETE/PUT/PATCH for group detail but only get and POST, seems a replica of the list view.

Menu

Please also register a menu group, we'll adapt this in #493.

[nemesifier]

here you're inherting ListCreateAPIView.

Please spend a bit more time testing this.

[pandafy]

I caught this on in #500. Forgot to push changes on this PR.

[nemesifier]

The API is missing the UUID of the group, without that it's not possible to determine the detail URL easily when browsing the API.

The registration of a new menu item is pending.

Also, I think I understood more the issue with the config editor.

I think we should set the default schema to be an object which allows any property, not an empty schema.

I'll take care of the rest with the CSS on that part.

[nemesifier]

In the admin page of the device, the label of the group field is "Device group", but since we are in the device edit page we don't need to repeat the word "Device" there, can you ensure it's named just "Group"? I think it could be done at model level to simplify things, it's always gonna be like that (the group attribute of a device is the device group).

[nemesifier]

Hey, why this change? It was better before!

[pandafy]

Makes it consistent with VPNCLIENT and explicitly show that DeviceGroup is it's own separate thing.

[nemesifier]

Please revert 8de60b2 as discussed recently.

[nemesifier]

I did the reverting.