feat(generic): add a view for enriching entities with external data

This view uses the importer to merge data from an URI (which is passed
as a GET parameter). If the URI is connected to another model instance,
the view redirects to the merge view. Otherwise the data from the URI
is fetched and presented to the user as a list of checkboxes for the
values that should be copied into the model instance.
If the URI is not yet connected to the instance, a new Uri
instance will be created and connected to the model instance.

apis_core/generic/abc.py

@@ -25,6 +25,10 @@ def get_edit_url(self):
         ct = ContentType.objects.get_for_model(self)
         return reverse("apis_core:generic:update", args=[ct, self.id])
 
+    def get_enrich_url(self):
+        ct = ContentType.objects.get_for_model(self)
+        return reverse("apis_core:generic:enrich", args=[ct, self.id])
+
     def get_absolute_url(self):
         ct = ContentType.objects.get_for_model(self)
         return reverse("apis_core:generic:detail", args=[ct, self.id])

apis_core/generic/forms/__init__.py

@@ -93,3 +93,21 @@ def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
         self.helper = FormHelper()
         self.helper.add_input(Submit("submit", "Merge"))
+
+
+class GenericEnrichForm(forms.Form):
+    def __init__(self, *args, **kwargs):
+        data = kwargs.pop("data", {})
+        instance = kwargs.pop("instance", None)
+        super().__init__(*args, **kwargs)
+        for key, value in data.items():
+            update_key = f"update_{key}"
+            self.fields[update_key] = forms.BooleanField(
+                required=False,
+                label=f"Update {key} from {getattr(instance, key)} to {value}",
+            )
+
+            self.fields[key] = forms.CharField(initial=value, required=False)
+            self.fields[key].widget = self.fields[key].hidden_widget()
+        self.helper = FormHelper()
+        self.helper.add_input(Submit("submit", "Submit"))

apis_core/generic/templates/generic/generic_enrich.html

@@ -0,0 +1,14 @@
+{% extends basetemplate|default:"base.html" %}
+{% load generic %}
+{% load crispy_forms_tags %}
+
+{% block content %}
+  <div class="container">
+    {% if form.fields %}
+      <h4 class="mb-4">
+        Updating <a href="{{ object.get_absolute_url }}">{{ object }}</a> using the data from <a href="{{ uri }}">{{ uri }}</a>
+      </h4>
+      {% crispy form form.helper %}
+    {% endif %}
+  </div>
+{% endblock %}

apis_core/generic/urls.py

@@ -54,6 +54,7 @@ def to_url(self, value):
                     views.MergeWith.as_view(),
                     name="merge",
                 ),
+                path("enrich/<int:pk>", views.Enrich.as_view(), name="enrich"),
                 path("autocomplete", views.Autocomplete.as_view(), name="autocomplete"),
                 path("import", views.Import.as_view(), name="import"),
                 path(

apis_core/generic/views.py

@@ -6,8 +6,9 @@
 from django.conf import settings
 from django.contrib import messages
 from django.contrib.auth.mixins import PermissionRequiredMixin
+from django.core.exceptions import ImproperlyConfigured
 from django.forms import modelform_factory
-from django.shortcuts import get_object_or_404
+from django.shortcuts import get_object_or_404, redirect
 from django.template.exceptions import TemplateDoesNotExist
 from django.template.loader import select_template
 from django.urls import reverse, reverse_lazy
@@ -20,11 +21,17 @@
 from django_tables2.columns import library
 from django_tables2.tables import table_factory
 
+from apis_core.apis_metainfo.models import Uri
 from apis_core.core.mixins import ListViewObjectFilterMixin
-from apis_core.utils.helpers import create_object_from_uri
+from apis_core.utils.helpers import create_object_from_uri, get_importer_for_model
 
 from .filtersets import GenericFilterSet
-from .forms import GenericImportForm, GenericMergeForm, GenericModelForm
+from .forms import (
+    GenericEnrichForm,
+    GenericImportForm,
+    GenericMergeForm,
+    GenericModelForm,
+)
 from .helpers import (
     first_member_match,
     generate_search_filter,
@@ -382,5 +389,78 @@ def form_valid(self, form):
         messages.info(self.request, f"Merged values of {self.other} into {self.object}")
         return super().form_valid(form)
 
+
+class Enrich(GenericModelMixin, PermissionRequiredMixin, FormView):
+    """
+    Enrich an entity with data from an external source
+    If so, it uses the proper Importer to get the data from the Uri and
+    provides the user with a form to select the fields that should be updated.
+    """
+
+    permission_action_required = "change"
+    template_name = "generic/generic_enrich.html"
+    form_class = GenericEnrichForm
+    importer_class = None
+
+    def setup(self, *args, **kwargs):
+        super().setup(*args, **kwargs)
+        self.object = get_object_or_404(self.model, pk=self.kwargs["pk"])
+        self.uri = self.request.GET.get("uri")
+        if not self.uri:
+            messages.error(self.request, "No uri parameter specified.")
+        self.importer_class = get_importer_for_model(self.model)
+
+    def get(self, *args, **kwargs):
+        if self.uri.isdigit():
+            return redirect(self.object.get_merge_url(self.uri))
+        try:
+            uriobj = Uri.objects.get(uri=self.uri)
+            if uriobj.root_object.id != self.object.id:
+                messages.info(
+                    self.request,
+                    f"Object with URI {self.uri} already exists, you were redirected to the merge form.",
+                )
+                return redirect(self.object.get_merge_url(uriobj.root_object.id))
+        except Uri.DoesNotExist:
+            pass
+        return super().get(*args, **kwargs)
+
+    def get_context_data(self, **kwargs):
+        ctx = super().get_context_data(**kwargs)
+        ctx["object"] = self.object
+        ctx["uri"] = self.uri
+        return ctx
+
+    def get_form_kwargs(self, *args, **kwargs):
+        kwargs = super().get_form_kwargs(*args, **kwargs)
+        kwargs["instance"] = self.object
+        try:
+            importer = self.importer_class(self.uri, self.model)
+            kwargs["data"] = importer.get_data()
+        except ImproperlyConfigured as e:
+            messages.error(self.request, e)
+        return kwargs
+
+    def form_valid(self, form):
+        """
+        Go through all the form fields and extract the ones that
+        start with `update_` and that are set (those are the checkboxes that
+        select which fields to update).
+        Then use the importers `import_into_instance` method to set those
+        fields values on the model instance.
+        """
+        update_fields = [
+            key.removeprefix("update_")
+            for (key, value) in self.request.POST.items()
+            if key.startswith("update_") and value
+        ]
+        importer = self.importer_class(self.uri, self.model)
+        importer.import_into_instance(self.object, fields=update_fields)
+        messages.info(self.request, f"Updated fields {update_fields}")
+        uri, created = Uri.objects.get_or_create(uri=self.uri, root_object=self.object)
+        if created:
+            messages.info(self.request, f"Added uri {self.uri} to {self.object}")
+        return super().form_valid(form)
+
     def get_success_url(self):
         return self.object.get_absolute_url()