Work on ontology

ontology/admin.py

@@ -4,7 +4,7 @@ __license__ = "AGPL v3"
 
 from django.contrib import admin
 
-from .models import Tag, Topic
+from .models import Tag, Topic, RelationAsym, RelationSym
 
 
 class TagAdmin(admin.ModelAdmin):
@@ -17,3 +17,7 @@ class TopicAdmin(admin.ModelAdmin):
     pass
 
 admin.site.register(Topic, TopicAdmin)
+
+
+admin.site.register(RelationAsym)
+admin.site.register(RelationSym)

ontology/constants.py

+__copyright__ = "Copyright 2016-2018, Stichting SciPost (SciPost Foundation)"
+__license__ = "AGPL v3"
+
+
+IS_INSTANCE_OF = 'is_instance_of'
+IS_SPECIALIZATION_OF = 'is_specialization_of'
+IS_REFINEMENT_OF = 'is_refinement_of'
+IS_USED_IN = 'is_used_in'
+IS_EXAMPLE_OF = 'is_example_of'
+
+TOPIC_RELATIONS_ASYM = (
+    (IS_INSTANCE_OF, 'is an instance of'),
+    (IS_SPECIALIZATION_OF, 'is a specialization of'),
+    (IS_REFINEMENT_OF, 'is a refinement of'),
+    (IS_USED_IN, 'is used in'),
+    (IS_EXAMPLE_OF, 'is an example of'),
+)
+
+
+ARE_RELATED = 'are_related'
+ARE_SYNONYMS = 'are_synonyms'
+
+TOPIC_RELATIONS_SYM = (
+    (ARE_RELATED, 'are related'),
+    (ARE_SYNONYMS, 'are synonyms'),
+)

ontology/migrations/0004_relationasym_relationsym.py

+# -*- coding: utf-8 -*-
+# Generated by Django 1.11.4 on 2018-10-27 18:33
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('ontology', '0003_auto_20181027_1748'),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='RelationAsym',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('relation', models.CharField(choices=[('is_instance_of', 'is an instance of'), ('is_specialization_of', 'is a specialization of'), ('is_refinement_of', 'is a refinement of'), ('is_used_in', 'is used in'), ('is_example_of', 'is an example of')], max_length=32)),
+                ('A', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='relation_LHS', to='ontology.Topic')),
+                ('B', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='relation_RHS', to='ontology.Topic')),
+            ],
+        ),
+        migrations.CreateModel(
+            name='RelationSym',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('relation', models.CharField(choices=[('are_related', 'are related'), ('are_synonyms', 'are synonyms')], max_length=32)),
+                ('topics', models.ManyToManyField(to='ontology.Topic')),
+            ],
+        ),
+    ]

ontology/models.py

@@ -4,6 +4,8 @@ __license__ = "AGPL v3"
 
 from django.db import models
 
+from .constants import TOPIC_RELATIONS_ASYM, TOPIC_RELATIONS_SYM
+
 
 class Tag(models.Model):
     """
@@ -32,3 +34,32 @@ class Topic(models.Model):
 
     def get_abolute_url(self):
         return reverse('ontology:topic_details', kwargs={'slug': self.slug})
+
+
+class RelationAsym(models.Model):
+    """
+    An asymmetric Relation between two Topics.
+    """
+    A = models.ForeignKey('ontology.Topic', on_delete=models.CASCADE,
+                          related_name='relation_LHS')
+    relation = models.CharField(max_length=32, choices=TOPIC_RELATIONS_ASYM)
+    B = models.ForeignKey('ontology.Topic', on_delete=models.CASCADE,
+                          related_name='relation_RHS')
+
+    def __str__(self):
+        return '%s %s %s' % (self.A, self.get_relation_display(), self.B)
+
+
+class RelationSym(models.Model):
+    """
+    A symmetric relation between multiple Topics.
+    """
+    topics = models.ManyToManyField('ontology.Topic')
+    relation = models.CharField(max_length=32, choices=TOPIC_RELATIONS_SYM)
+
+    def __str__(self):
+        text = ''
+        for topic in self.topics.all():
+            text += '%s, ' % topic
+        text += self.get_relation_display()
+        return text

ontology/templates/ontology/_topic_card.html

@@ -15,5 +15,28 @@
       {% endfor %}
     </ul>
     {% endif %}
+    <h4>Relations</h4>
+    <div class="row">
+      <div class="col-6">
+	<h5>asymmetric:</h5>
+	<ul>
+	  {% for rel in relations_asym %}
+	  <li>{% if rel.A != topic %}<a href="{% url 'ontology:topic_details' slug=rel.A.slug %}">{{ rel.A}}</a>{% else %}{{ rel.A }}{% endif %} {{ rel.get_relation_display }} {% if rel.B != topic %}<a href="{% url 'ontology:topic_details' slug=rel.B.slug %}">{{ rel.B }}</a>{% else %}{{ rel.B }}{% endif %}</li>
+	  {% empty %}
+	  <li>No relations have been defined</li>
+	  {% endfor %}
+	</ul>
+      </div>
+      <div class="col-6">
+	<h5>symmetric:</h5>
+	<ul>
+	  {% for rel in topic.relationsym_set.all %}
+	  <li>{% for reltopic in rel.topics.all %}{% if reltopic != topic %}<a href="{% url 'ontology:topic_details' slug=reltopic.slug %}">{{ reltopic }}</a>{% else %}{{ reltopic }}{% endif %}, {% endfor %} {{ rel.get_relation_display }}</li>
+	  {% empty %}
+	  <li>No symmetric relations have been defined</li>
+	  {% endfor %}
+	</ul>
+      </div>
+    </div>
   </div>
 </div>

ontology/views.py

@@ -3,11 +3,12 @@ __license__ = "AGPL v3"
 
 
 from django.core.urlresolvers import reverse_lazy
+from django.db.models import Q
 from django.views.generic.detail import DetailView
 from django.views.generic.edit import CreateView, UpdateView
 from django.views.generic.list import ListView
 
-from .models import Topic
+from .models import Topic, RelationAsym, RelationSym
 
 from scipost.mixins import PermissionsMixin
 
@@ -40,3 +41,8 @@ class TopicListView(ListView):
 
 class TopicDetailView(DetailView):
     model = Topic
+
+    def get_context_data(self, *args, **kwargs):
+        context = super().get_context_data(*args, **kwargs)
+        context['relations_asym'] = RelationAsym.objects.filter(Q(A=self.object) | Q(B=self.object))
+        return context