Implementing a full-text search engine with Django and PostgreSQL

Module03/mysite/blog/forms.py

@@ -11,3 +11,7 @@ class CommentForm(forms.ModelForm):
     class Meta:
         model = Comment
         fields = ['name', 'email', 'body']
+
+
+class SearchForm(forms.Form):
+    query = forms.CharField()

Module03/mysite/blog/templates/blog/post/search.html

@@ -0,0 +1,34 @@
+{% extends "blog/base.html" %}
+{% load blog_tags %}
+
+{% block title %}Search{% endblock %}
+
+{% block content %}
+    {% if query %}
+        <h1>Posts containing "{{ query }}"</h1>
+        <h3>
+            {% with results.count as total_results %}
+                Found {{ total_results }} result{{ total_results|pluralize }}
+            {% endwith %}
+        </h3>
+
+        {% for post in results %}
+            <h4>
+                <a href="{{ post.get_absolute_url }}">
+                    {{ post.title }}
+                </a>
+            </h4>
+            {{ post.body|markdown|truncatewords_html:12 }}
+        {% empty %}
+            <p>There are no results for your query.</p>
+        {% endfor %}
+        <p><a href="{% url "blog:post_search" %}">Search again</a></p>
+
+    {% else %}
+        <h1>Search for posts</h1>
+        <form method="get">
+            {{ form.as_p }}
+            <input type="submit" value="Search">
+        </form>
+    {% endif %}
+{% endblock %}

Module03/mysite/blog/urls.py

@@ -10,4 +10,5 @@
     path('<int:year>/<int:month>/<int:day>/<slug:post>/', views.post_detail, name='post_detail'),
     path('<int:post_id>/share/', views.post_share, name='post_share'),
     path('<int:post_id>/comment/', views.post_comment, name='post_comment'),
+    path('search/', views.post_search, name='post_search'),
 ]

Module03/mysite/blog/views.py

@@ -2,11 +2,13 @@
 from .models import Post
 from django.core.paginator import Paginator, EmptyPage, PageNotAnInteger 
 from django.views.generic import ListView
-from .forms import EmailPostForm, CommentForm
+from .forms import EmailPostForm, CommentForm, SearchForm
 from django.core.mail import send_mail
 from django.views.decorators.http import require_POST
 from taggit.models import Tag
 from django.db.models import Count
+from django.contrib.postgres.search import SearchVector, SearchQuery, SearchRank
+
 
 def post_list(request, tag_slug=None):
     post_list = Post.objects.all()
@@ -87,3 +89,19 @@ def post_comment(request, post_id):
         # Save the comment to the database
         comment.save()
     return render(request, 'blog/post/comment.html', {'post': post, 'form': form, 'comment': comment})
+
+
+
+def post_search(request):
+    form = SearchForm()
+    query = None
+    results = []
+    if 'query' in request.GET:
+        form = SearchForm(request.GET)
+        if form.is_valid():
+            query = form.cleaned_data['query']
+            search_vector = SearchVector('title', 'body')
+            search_query = SearchQuery(query, config='english')
+            results = Post.objects.annotate(search=search_vector, rank=SearchRank(search_vector, search_query)).filter(search=search_query).order_by('-rank')
+
+    return render(request,'blog/post/search.html',{'form': form,'query': query,'results': results})

Module03/mysite/mysite/settings.py

@@ -43,6 +43,7 @@
     'taggit',
     'django.contrib.sites',
     'django.contrib.sitemaps',
+    'django.contrib.postgres',
 ]
 
 MIDDLEWARE = [
@@ -81,12 +82,13 @@
 
 DATABASES = {
     'default': {
-        'ENGINE': 'django.db.backends.sqlite3',
-        'NAME': BASE_DIR / 'db.sqlite3',
+        'ENGINE': 'django.db.backends.postgresql',
+        'NAME': 'blog',
+        'USER': 'blog',
+        'PASSWORD': '123456',
     }
 }
 
-
 # Password validation
 # https://docs.djangoproject.com/en/4.2/ref/settings/#auth-password-validators