Django: 1. Start first application

Following: https://tutorial.djangogirls.org

Python object oriented programming:

Object has 'Properties' and 'Methods'

-Start application in the django project

(env) $ python manage.py startapp app_name

Failures that I encounterd:

-django application start error

django.core.exceptions.ImproperlyConfigured: Error loading MySQLdb module.
 
Did you install mysqlclient?

>>

$ sudo pip install mysqlclient

-pip install error

compilation terminated.

    error: command 'gcc' failed with exit status 1

>>

$ yum search python3 | grep devel

$ yum install python36u-devel

-Say to django that I will use 'app_name'

application/settings.py

# Application definition
 
INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'app_name'
]

-Make a sample model

app_name/migrations/models.py

from django.db import models
from django.utils import timezone
 
 
class Post(models.Model):
    author = models.ForeignKey('auth.User', on_delete=models.CASCADE)
    title = models.CharField(max_length=200)
    text = models.TextField()
    created_date = models.DateTimeField(
            default=timezone.now)
    published_date = models.DateTimeField(
            blank=True, null=True)
 
    def publish(self):
        self.published_date = timezone.now()
        self.save()
 
    def __str__(self):
        return self.title

-Notice that the new model is ready to database

(env) $ python manage.py makemigrations app_name

-If you met this WARNINGS,

WARNINGS:

?: (mysql.W002) MySQL Strict Mode is not set for database connection 'default'

HINT: MySQL's Strict Mode fixes many data integrity problems in MySQL, such as data truncation upon insertion, by escalating warnings into errors. It is strongly recommended you activate it. See: https://docs.djangoproject.com/en/2.0/ref/databases/#mysql-sql-mode

>>

MariaDB [(none)]> set sql_mode='STRICT_TRANS_TABLES'
    -> ;
Query OK, 0 rows affected (0.01 sec)
 

-Apply the model to the database

(env) $ python manage.py migrate

-Create superuser for django admin

(env) $ python manage.py createsuperuser

-Create sample django admin

from django.contrib import admin
from .models import Post
 
admin.site.register(Post)

-View admin page: 127.0.0.1:8000/admin