Create/Update Study Area

[docuracy]

• Slide
• Template: /areas/templates/areas/area_create.html
• View: AreaCreateView(CreateView)
• URL Pattern: 'create/'
• Example on localhost: http://localhost:8001/areas/create/
• Example on v2: https://whgazetteer.org/areas/create/

[docuracy]

Questions:

• [ ] I've disabled the GeoJSON box to prevent users from thinking that they have to enter something there. But perhaps you intend that they should be able to paste valid GeoJSON there rather than using the ccode or drawing options?
• [x] Is the form.geojson value always going to be null for this page? If so, the AreaCreateView should not be dealing with forms, and nor should area_create.html be dealing with form values. I suspect that forms are needed only for AreaUpdateView. Nevertheless, I'll code the map_init function of areas.js to load any passed GeoJSON because I suspect that the same areas.js module will be used for that.
• [ ] The Django template was not loading any bootstrap.bundle.min.js. I've hard-coded it in, but suspect that it's been inadvertently deleted from main/base.html and so will be missing from other pages too.
• [ ] Implementing the basemap switcher to allow a satellite basemap to be used is fraught with complications. It could be done - is it still considered desirable?
• [ ] I've provided code to add in the river and watershed GeoJSON data, but the URLs are returning empty arrays at present. Are these redundant, and so should their loading be removed from the code?
• [x] It would be a good idea (I think) to clone the MapBox code (js+css) used for drawing shapes and avoid having to fetch it from a potentially-unreliable external source.
• [ ] Is it necessary to disable the tabs for updating a study area? Wouldn't it be possible - and sometimes desirable - to simply replace ccode shapes with drawn shapes and vice versa?

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TO DO

• [x] Newly-created study areas don't display: this is because /areas/views.py sets self.success_url = '/mystudyareas', but that url is commented out in `/urls.py'.

KG: "The success url should be /dashboard ...

In v2, a simple polygon hull is computed whether a buffer is requested or not, and its that geometry written to the geojson form field and saved to the Area record. As you have it now, a FeatureCollection appears there. When the page is refreshed as an edit page, a count_public @property on the Area model is consulted to display the number of place records that lie within it. It can’t convert the FeatureCollection in this line: areageom = GEOSGeometry(json.dumps(self.geojson)) But a further issue is, ... what about multiple discontinuous areas making up a study area?"

SG: In areas.js the native MapLibre draw.getAll() method returns a FeatureCollection. We need to extract and merge the feature geometries into a single GeometryCollection, which is now simplified and cleaned by the form validation script in the form class AreaModelForm. It seems that this is the form required for successful conversion to a .wkt which can be used in the geom__within calculation in the model class Area.