feat: make generic crudl views

Create generic Create, View, Update, Delete and List views that work
with ContentTypes

Closes: #509

apis_core/core/templatetags/apiscore.py

@@ -1,5 +1,8 @@
+from itertools import chain
+
 from django import template
 from django.conf import settings
+from django.contrib.contenttypes.models import ContentType
 
 
 register = template.Library()
@@ -13,3 +16,35 @@ def shared_url():
 @register.simple_tag
 def page_range(paginator, number):
     return paginator.get_elided_page_range(number=number)
+
+
+@register.filter
+def contenttype(model):
+    return ContentType.objects.get_for_model(model)
+
+
+@register.simple_tag
+def modeldict(instance, fields=None, exclude=None):
+    opts = instance._meta
+    data = {}
+    for f in chain(opts.concrete_fields, opts.private_fields, opts.many_to_many):
+        if not getattr(f, "editable", False):
+            continue
+        if fields is not None and f.name not in fields:
+            continue
+        if exclude and f.name in exclude:
+            continue
+        field = instance._meta.get_field(f.name)
+        data[field] = instance._get_FIELD_display(field)
+        if getattr(field, "m2m_field_name", False):
+            values = getattr(instance, field.name).all()
+            data[field] = ", ".join([str(value) for value in values])
+    return data
+
+
+@register.simple_tag
+def contenttypes(app_labels=None):
+    if app_labels:
+        app_labels = app_labels.split(",")
+        return ContentType.objects.filter(app_label__in=app_labels)
+    return ContentType.objects.all()

apis_core/generic/api_views.py

@@ -0,0 +1,14 @@
+from rest_framework import viewsets
+from .serializers import serializer_factory
+
+
+class GenericViewSet(viewsets.ModelViewSet):
+    def dispatch(self, *args, **kwargs):
+        self.model = kwargs.get("contenttype").model_class()
+        return super().dispatch(*args, **kwargs)
+
+    def get_queryset(self):
+        return self.model.objects.all()
+
+    def get_serializer_class(self):
+        return serializer_factory(self.model)

apis_core/generic/filtersets.py

@@ -0,0 +1,30 @@
+from django_filters.filterset import FilterSet
+from .forms import GenericFilterSetForm
+
+
+class GenericFilterSet(FilterSet):
+    @property
+    def form(self):
+        if not hasattr(self, "_form"):
+            Form = self.get_form_class()
+            if self.is_bound:
+                self._form = Form(
+                    self.data, prefix=self.form_prefix, model=self._meta.model
+                )
+            else:
+                self._form = Form(prefix=self.form_prefix, model=self._meta.model)
+        return self._form
+
+
+def filterset_factory(model, filterset=GenericFilterSet, fields="__all__"):
+    meta = type(
+        str("Meta"),
+        (object,),
+        {"model": model, "fields": fields, "form": GenericFilterSetForm},
+    )
+    filterset = type(
+        str("%sFilterSet" % model._meta.object_name),
+        (filterset,),
+        {"Meta": meta},
+    )
+    return filterset

apis_core/generic/forms.py

@@ -0,0 +1,52 @@
+from django import forms
+from django.contrib.contenttypes.models import ContentType
+from django.urls import reverse
+from crispy_forms.helper import FormHelper
+from crispy_forms.layout import Submit
+from dal import autocomplete
+
+
+class GenericFilterSetForm(forms.Form):
+    columns = forms.MultipleChoiceField(required=False)
+
+    def __init__(self, *args, **kwargs):
+        model = kwargs.pop("model")
+        super().__init__(*args, **kwargs)
+        self.fields["columns"].choices = [
+            (field.name, field.verbose_name) for field in model._meta.fields
+        ]
+
+        self.helper = FormHelper()
+        self.helper.form_method = "GET"
+        self.helper.add_input(Submit("submit", "Submit"))
+
+    def clean(self):
+        self.cleaned_data = super().clean()
+        self.cleaned_data.pop("columns", None)
+        return self.cleaned_data
+
+
+class GenericModelForm(forms.ModelForm):
+    class Meta:
+        fields = "__all__"
+
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self.helper = FormHelper(self)
+        self.helper.add_input(Submit("submit", "Submit"))
+
+        # override the fields pointing to other models,
+        # to make them use the autocomplete widgets
+        override_fieldtypes = {
+            "ModelMultipleChoiceField": autocomplete.ModelSelect2Multiple,
+            "ModelChoiceField": autocomplete.ModelSelect2,
+        }
+        for field in self.fields:
+            clsname = self.fields[field].__class__.__name__
+            if clsname in override_fieldtypes.keys():
+                ct = ContentType.objects.get_for_model(
+                    self.fields[field]._queryset.model
+                )
+                url = reverse("apis_core:generic:autocomplete", args=[ct])
+                self.fields[field].widget = override_fieldtypes[clsname](url)
+                self.fields[field].widget.choices = self.fields[field].choices

apis_core/generic/helpers.py

@@ -0,0 +1,53 @@
+import functools
+import inspect
+import importlib
+
+from django.db.models import CharField, TextField, Q, Model
+
+
+def generate_search_filter(model, query):
+    fields_to_search = [
+        field.name
+        for field in model._meta.fields
+        if isinstance(field, (CharField, TextField))
+    ]
+    q = Q()
+
+    for token in query:
+        q &= functools.reduce(
+            lambda acc, field_name: acc | Q(**{f"{field_name}__icontains": token}),
+            fields_to_search,
+            Q(),
+        )
+
+    return model.objects.filter(q)
+
+
+def mro_paths(model):
+    paths = []
+    for cls in filter(lambda x: x not in Model.mro(), model.mro()):
+        paths.append(cls.__module__.split(".")[:-1] + [cls.__name__])
+    return paths
+
+
+def template_names_via_mro(model, suffix=""):
+    mro_prefix_list = ["/".join(prefix) for prefix in mro_paths(model)]
+    return [f"{prefix.lower()}{suffix}" for prefix in mro_prefix_list]
+
+
+def class_from_path(classpath):
+    module, cls = classpath.rsplit(".", 1)
+    try:
+        members = inspect.getmembers(importlib.import_module(module))
+        members = list(filter(lambda c: c[0] == cls, members))
+    except ModuleNotFoundError:
+        return False
+    if members:
+        return members[0][1]
+    return False
+
+
+def first_match_via_mro(model, path: str = "", suffix: str = ""):
+    paths = list(map(lambda x: x[:-1] + [path] + x[-1:], mro_paths(model)))
+    classes = [".".join(prefix) + suffix for prefix in paths]
+    return next(map(class_from_path, classes), None)

apis_core/generic/serializers.py

@@ -0,0 +1,11 @@
+from rest_framework.serializers import ModelSerializer
+
+
+def serializer_factory(model, serializer=ModelSerializer, fields="__all__", **kwargs):
+    meta = type(str("Meta"), (object,), {"model": model, "fields": fields})
+    serializer = type(
+        str("%sModelSerializer" % model._meta.object_name),
+        (serializer,),
+        {"Meta": meta},
+    )
+    return serializer

apis_core/generic/tables.py

@@ -0,0 +1,53 @@
+import django_tables2 as tables
+
+
+class CustomTemplateColumn(tables.TemplateColumn):
+    template_name = None
+    orderable = None
+    exclude_from_export = False
+    verbose_name = None
+
+    def __init__(self, *args, **kwargs):
+        super().__init__(
+            template_name=self.template_name,
+            orderable=self.orderable,
+            exclude_from_export=self.exclude_from_export,
+            verbose_name=self.verbose_name,
+            *args,
+            **kwargs
+        )
+
+
+class DeleteColumn(CustomTemplateColumn):
+    template_name = "columns/delete.html"
+    orderable = False
+    exclude_from_export = True
+    verbose_name = ""
+
+
+class EditColumn(CustomTemplateColumn):
+    template_name = "columns/edit.html"
+    orderable = False
+    exclude_from_export = True
+    verbose_name = ""
+
+
+class DescriptionColumn(CustomTemplateColumn):
+    template_name = "columns/description.html"
+    orderable = False
+
+
+class GenericTable(tables.Table):
+    edit = EditColumn()
+    desc = DescriptionColumn()
+    delete = DeleteColumn()
+
+    class Meta:
+        fields = ["id", "desc"]
+
+    def __init__(self, *args, **kwargs):
+        # if there is no custom sequence set, move `edit` and `delete` to the back
+        if "sequence" not in kwargs:
+            kwargs["sequence"] = ["...", "edit", "delete"]
+
+        super().__init__(*args, **kwargs)

apis_core/generic/templates/columns/delete.html

@@ -0,0 +1,3 @@
+{% load apiscore %}
+<a href="{% url 'apis_core:generic:delete' record|contenttype record.id %}"
+   class="text-danger">✘</a>

apis_core/generic/templates/columns/description.html

@@ -0,0 +1,2 @@
+{% load apiscore %}
+<a href="{% url 'apis_core:generic:detail' record|contenttype record.id %}">{{ record }}</a>

apis_core/generic/templates/columns/edit.html

@@ -0,0 +1,3 @@
+{% load apiscore %}
+<a href="{% url 'apis_core:generic:update' record|contenttype record.id %}"
+   class="text-warning">✎</a>

apis_core/generic/templates/generic/generic_confirm_delete.html

@@ -0,0 +1,20 @@
+{% extends basetemplate|default:"base.html" %}
+
+{% block content %}
+  <div class="modal-dialog">
+    <div class="modal-content">
+      <div class="modal-body">
+        <form action="" method="post">
+          {% csrf_token %}
+          <h4>
+            Confirm deletion of:
+            <div class="text-center">
+            <strong>{{ object }}</strong>
+            </div>
+          </h4>
+          <input class="btn btn-danger" type="submit" value="Yes, delete" />
+        </form>
+      </div>
+    </div>
+  </div>
+{% endblock content %}

apis_core/generic/templates/generic/generic_content.html

@@ -0,0 +1,18 @@
+{% extends basetemplate|default:"base.html" %}
+
+{% block content %}
+  <div class="container-fluid">
+    <div class="row">
+      <div class="col">
+
+        {% block col %}
+        {% endblock col %}
+
+      </div>
+
+      {% block additionalcols %}
+      {% endblock additionalcols %}
+
+    </div>
+  </div>
+{% endblock content %}

apis_core/generic/templates/generic/generic_detail.html

@@ -0,0 +1,23 @@
+{% extends "generic/generic_content.html" %}
+{% load apiscore %}
+
+{% if object %}
+
+  {% block col %}
+    <div class="card">
+      <div class="card-header">{{ object }}</div>
+      <div class="card-body">
+        <table class="table table-hover">
+          {% modeldict object as d %}
+          {% for key, value in d.items %}
+            <tr>
+              <th>{{ key.verbose_name }}</th>
+              <td>{{ value }}</td>
+            </tr>
+          {% endfor %}
+        </table>
+      </div>
+    </div>
+  {% endblock col %}
+
+{% endif %}

apis_core/generic/templates/generic/generic_form.html

@@ -0,0 +1,9 @@
+{% extends "generic/generic_content.html" %}
+{% load crispy_forms_tags %}
+
+{% block col %}
+  <div class="card">
+    <div class="card-header">Edit {{ object }}</div>
+    <div class="card-body">{% crispy form form.helper %}</div>
+  </div>
+{% endblock col %}