Merge branch 'master' of https://github.com/PdxCodeGuild/Class_Raven

4 Django/demo/n_plus_one/manage.py

@@ -0,0 +1,22 @@
+#!/usr/bin/env python
+"""Django's command-line utility for administrative tasks."""
+import os
+import sys
+
+
+def main():
+    """Run administrative tasks."""
+    os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'n_plus_one_proj.settings')
+    try:
+        from django.core.management import execute_from_command_line
+    except ImportError as exc:
+        raise ImportError(
+            "Couldn't import Django. Are you sure it's installed and "
+            "available on your PYTHONPATH environment variable? Did you "
+            "forget to activate a virtual environment?"
+        ) from exc
+    execute_from_command_line(sys.argv)
+
+
+if __name__ == '__main__':
+    main()

4 Django/demo/n_plus_one/n_plus_one_app/admin.py

@@ -0,0 +1,5 @@
+from django.contrib import admin
+
+from .models import *
+
+admin.site.register([BlogPost, Comment])

4 Django/demo/n_plus_one/n_plus_one_app/apps.py

@@ -0,0 +1,6 @@
+from django.apps import AppConfig
+
+
+class NPlusOneAppConfig(AppConfig):
+    default_auto_field = 'django.db.models.BigAutoField'
+    name = 'n_plus_one_app'

4 Django/demo/n_plus_one/n_plus_one_app/management/commands/populate.py

@@ -0,0 +1,89 @@
+from django.core.management.base import BaseCommand
+import requests
+
+from n_plus_one_app.models import *
+
+def split_name(name):
+    '''Split the full name from the API JSON into a first and last name, handling two three-part names'''
+    match name:
+        case 'Mrs. Dennis Schulist':
+            split_name = name.split(' ')[1:]
+
+        case 'Nicholas Runolfsdottir V':
+            split_name = name.split(' ')[:2]
+
+        case default:
+            split_name = name.split(' ')
+
+    return split_name
+
+class Command(BaseCommand):
+
+    def handle(self, *args, **options):
+
+        User.objects.filter(is_superuser=False).delete()
+        BlogPost.objects.all().delete()
+        Comment.objects.all().delete()
+
+        BASE_URL = "http://jsonplaceholder.typicode.com"
+
+        for x in range(10):
+            users = requests.get(BASE_URL + '/users').json()
+            user_ids = []
+            for user in users:
+                username = user['username']
+                email = user['email']
+                name = user['name']
+
+                first_name, last_name = split_name(name)
+
+                new_user = User.objects.create_user(
+                    username=username + str(x),
+                    email=email,
+                    password='pass3412',
+                    first_name=first_name,
+                    last_name=last_name
+                )
+
+                user_ids.append(new_user.id)
+
+            # list of all the user ids
+            blogpost_ids = []
+
+            # create posts
+            posts = requests.get(BASE_URL + '/posts').json()
+            for post in posts:
+                # user_id is the value at the index of the userId from the API
+                user_id = user_ids[int(post['userId'])-1]
+                user = User.objects.get(id=user_id)
+
+                title = post['title']
+                body = post['body']
+
+                user = User.objects.get(id=user_id)
+
+                new_blogpost = BlogPost.objects.create(
+                    user=user,
+                    title=title,
+                    body=body
+                )
+
+                blogpost_ids.append(new_blogpost.id)
+
+
+            # create comments
+            comments = requests.get(BASE_URL + '/comments').json()
+            for comment in comments:
+                name = comment['name']
+                body = comment['name']
+
+                # user_id is the value at the index of the userId from the API
+                blogpost_id = blogpost_ids[int(comment['postId'])-1]
+                blogpost = BlogPost.objects.get(id=blogpost_id)
+
+                new_comment = Comment.objects.create(
+                    blogpost = blogpost,
+                    name=name,
+                    body=body
+                )
+

4 Django/demo/n_plus_one/n_plus_one_app/migrations/0001_initial.py

@@ -0,0 +1,36 @@
+# Generated by Django 4.0.2 on 2022-02-10 21:35
+
+from django.conf import settings
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    initial = True
+
+    dependencies = [
+        migrations.swappable_dependency(settings.AUTH_USER_MODEL),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='BlogPost',
+            fields=[
+                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('title', models.CharField(max_length=100)),
+                ('body', models.CharField(max_length=1000)),
+                ('user', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='blogposts', to=settings.AUTH_USER_MODEL)),
+            ],
+        ),
+        migrations.CreateModel(
+            name='Comment',
+            fields=[
+                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('name', models.CharField(max_length=500)),
+                ('email', models.EmailField(max_length=100)),
+                ('body', models.CharField(max_length=1000)),
+                ('blogpost', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='blogposts', to='n_plus_one_app.blogpost')),
+            ],
+        ),
+    ]

4 Django/demo/n_plus_one/n_plus_one_app/migrations/0002_alter_comment_blogpost.py

@@ -0,0 +1,19 @@
+# Generated by Django 4.0 on 2022-02-12 01:05
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('n_plus_one_app', '0001_initial'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='comment',
+            name='blogpost',
+            field=models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='comments', to='n_plus_one_app.blogpost'),
+        ),
+    ]

4 Django/demo/n_plus_one/n_plus_one_app/models.py

@@ -0,0 +1,13 @@
+from django.db import models
+from django.contrib.auth.models import User
+
+class BlogPost(models.Model):
+    user = models.ForeignKey(User, on_delete=models.CASCADE, related_name='blogposts')
+    title = models.CharField(max_length=100)
+    body = models.CharField(max_length=1000)
+
+class Comment(models.Model):
+    blogpost = models.ForeignKey(BlogPost, on_delete=models.CASCADE, related_name='comments')
+    name = models.CharField(max_length=500)
+    email = models.EmailField(max_length=100)
+    body = models.CharField(max_length=1000)

4 Django/demo/n_plus_one/n_plus_one_app/templates/index.html

@@ -0,0 +1,28 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Document</title>
+</head>
+<body>
+    <h1>{{query_count}} queries were made</h1>
+
+
+    {% for user in users %}
+        {{user.username}}
+        {% for blogpost in user.blogposts.all %}
+            {{blogpost.title}}
+
+            {% for comment in blogpost.comments.all %}
+                {{comment.name}}
+
+            {% endfor %}
+
+        {% endfor %}
+
+    {% endfor %}
+
+</body>
+</html>

4 Django/demo/n_plus_one/n_plus_one_app/tests.py

@@ -0,0 +1,3 @@
+from django.test import TestCase
+
+# Create your tests here.

4 Django/demo/n_plus_one/n_plus_one_app/urls.py

@@ -0,0 +1,8 @@
+from django.urls import path
+from . import views
+
+app_name = 'n_plus_one'
+
+urlpatterns = [
+    path('', views.index, name='index')
+]

4 Django/demo/n_plus_one/n_plus_one_app/views.py

@@ -0,0 +1,42 @@
+from django.shortcuts import render
+
+from django.db import connection, reset_queries
+
+from .models import *
+
+
+def index(request):
+
+    # retrieve only the user objects, not their blogposts or the blogposts' comments
+    # 1102 queries to get all the comments
+    # users = User.objects.all()
+
+    # retrieve the users and all of their blogposts, but not the comments
+    # 101 queries to get all the comments
+    # users = User.objects.all().prefetch_related('blogposts')
+
+    # retreive the users, their blogposts and the comments
+    # 3 queries to get all the comments
+    users = User.objects.all().prefetch_related('blogposts__comments')
+
+
+    # print(users.blogposts.first().comments.all())
+
+    # for user in users:
+    #     # print(user)
+    #     for blogpost in user.blogposts.all():
+    #         x = blogpost
+    #         print(blogpost)
+    #         for comment in blogpost.comments.all():
+    #             print(comment)
+    #             x = comment # evaluate the comment into a variable
+
+
+    query_count = len(connection.queries)
+
+    context = {
+        'query_count': query_count,
+        'users': users
+    }
+
+    return render(request, 'index.html', context)

4 Django/demo/n_plus_one/n_plus_one_proj/asgi.py

@@ -0,0 +1,16 @@
+"""
+ASGI config for n_plus_one_proj project.
+
+It exposes the ASGI callable as a module-level variable named ``application``.
+
+For more information on this file, see
+https://docs.djangoproject.com/en/4.0/howto/deployment/asgi/
+"""
+
+import os
+
+from django.core.asgi import get_asgi_application
+
+os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'n_plus_one_proj.settings')
+
+application = get_asgi_application()