From 843e3bfb0a31f82f341161bf7d74f791402cbb0d Mon Sep 17 00:00:00 2001
From: Gabriel Augendre <gabriel@augendre.info>
Date: Thu, 31 Dec 2020 13:51:13 +0100
Subject: [PATCH] Add a related articles section at the bottom of articles

---
 articles/models.py                            | 19 +++++++++++++++++++
 .../templates/articles/article_detail.html    | 14 ++++++++++++++
 2 files changed, 33 insertions(+)

diff --git a/articles/models.py b/articles/models.py
index 82efe13..9e494ee 100644
--- a/articles/models.py
+++ b/articles/models.py
@@ -1,3 +1,4 @@
+import random
 import re
 import uuid
 from functools import cached_property
@@ -132,3 +133,21 @@ class Article(AdminUrlMixin, models.Model):
         if content:
             return readtime.of_html(content).minutes
         return 0
+
+    @cached_property
+    def get_related_articles(self):
+        related_articles = set()
+        for keyword in self.get_formatted_keywords:
+            potential_articles = Article.objects.filter(
+                keywords__icontains=keyword,
+                status=Article.PUBLISHED,
+            ).exclude(pk=self.pk)
+            for article in potential_articles:
+                if keyword in article.get_formatted_keywords:
+                    related_articles.add(article)
+        sample_size = min([len(related_articles), 3])
+        return random.sample(related_articles, sample_size)
+
+    @cached_property
+    def get_formatted_keywords(self):
+        return list(map(lambda k: k.strip().lower(), self.keywords.split(",")))
diff --git a/articles/templates/articles/article_detail.html b/articles/templates/articles/article_detail.html
index a48fdd3..053c2ec 100644
--- a/articles/templates/articles/article_detail.html
+++ b/articles/templates/articles/article_detail.html
@@ -17,4 +17,18 @@
             {{ article.get_formatted_content|safe }}
         </div>
     </article>
+    {% if article.get_related_articles %}
+        <section>
+            <hr>
+            <h4>You might also like</h4>
+            {% for related in article.get_related_articles %}
+                <article>
+                    <h5>
+                        <a href="{% url "article-detail" slug=related.slug %}">{{ related.title }}</a>
+                    </h5>
+                    <p>{{ related.get_description }}</p>
+                </article>
+            {% endfor %}
+        </section>
+    {% endif %}
 {% endblock %}