pyworking 2016/12/10 django

00-nastaveni.txt

Nastavit http://bit.ly/pyworking-prg-01
=======================================

* Pythonanywhere.com - ucet
* Github.com - ucet
* Vytvorit na https://github.com repository "prvniblog"
  - Initialize with README
  - Add .gitignore Python
  - Create repository
! git clone https://github.com/MUJUCET/prvniblog
! cd prvniblog
! python3 -m venv myvenv
! source myvenv/bin/activate
! pip install django
! pip freeze
  django==1.10.4
  

01-notes.txt

Requirements
============

* Github account
* Zakladni zkusenosti s gitem (add, push)
* Zkusenosti s cli (mkdir / ls / edit file)
* Repository na Githubu prvniblog s README souborem
* Pythonanywhere account

Uvod
====

* Co se naucis
  - cli piskvorky fajn, ale web je lepsi
  - zaklady webu (internetu?)
  - popularni FW v pythonu pro weby (django)
  
Instalace
=========

* Viz requirements
! Vsichni by 'pip freeze | django'
! django-admin help

Jak funguje internet
====================

* Web stranka -> soubor v HTML (ctrl+u)
* Ulozena na serveru -> serviruji data
* Internet -> servery "ruzne" propojeny kabely
* Request -> dopis s (IP) adresou, ktery se posila pres posty/routery na cil/server
* DNS -> Telefonni seznam, znate jmeno, dostanete cislo a adresu
* HTTP -> Format dopisu (adresa, znamka, poradi jmeno, ulice, psc, zpatecni adresa...)

Co je Django
============

* Knihovna/Framework
* Resi spolecne problemy vsech webu:
  HTTP, registrace, uzivatele, urlresolving url->view/fce, generovani html, ...
* Frameworku je hodne (python i nepython)

Muj prvni projekt
=================
! git clone https://github.com/<your-github-username>/prvniblog.git
! cd prvniblog
# install django
! python3 -m venv myvenv
! source myvenv/bin/activate
! pip install --upgrade pip
! pip install django~=1.9.0
# initialize project
! django-admin startproject mysite .
! ls
! ls mysite
* Co se stalo?
* manage.py
* urls.py
* wsgi.py
* settings.py
-- settings.py --
! TIME_ZONE = 'Europe/Prague'
! DATABASES = {
        'default': {
            'ENGINE': 'django.db.backends.sqlite3',
            'NAME': os.path.join(BASE_DIR, 'db.sqlite3'),
        }
    }
! STATIC_ROOT = os.path.join(BASE_DIR, 'static')
! ALLOWED_HOSTS = ['127.0.0.1', '.pythonanywhere.com']



* Nalejem si databazi
! python manage.py migrate

* Pustime server
! python manage.py runserver

Modely
======

* Pamatujete si objekty?
* Co bude mit objekt blog post?
* Vytvorme si appku blog
! python manage.py startapp blog
! ls
! ls blog
-- settings.py --
! INSTALLED_APPS = (
         'django.contrib.admin',
         'django.contrib.auth',
         'django.contrib.contenttypes',
         'django.contrib.sessions',
         'django.contrib.messages',
         'django.contrib.staticfiles',
         'blog',
  )

* Vytvorime model pro blog
-- blog/models.py --
    from django.db import models
    from django.utils import timezone


    class Post(models.Model):
        author = models.ForeignKey('auth.User')
        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

* Reknem djangu o novym modelu
! python manage.py makemigrations blog
* A at ho prida do nasi db
! python manage.py migrate blog

Admin
=====
* Web rozhrani pro spravce
* Chceme pridat nas Post

-- blog/admin.py --
    from django.contrib import admin
    from .models import Post

    admin.site.register(Post)

* Udelame si ucet
! python manage.py createsuperuser
* Spustime server a prihlasime se
! python manage.py runserver
* otevri http://127.0.0.1:8000/admin
* pohraj si s nim (hlavne s posty), pridej zaznam atd
\o/

Deploy (DELAT urcite, nejpozdeni 20min pred koncem!)
====================================================
* Poslem to na github
! git status
* pridame par zaznamu do .gitignore
-- .gitignore --
/db.sqlite3
/myvenv/
! git add .gitignore mysite blog manage.py
! git commit -m 'blog s adminem'
! git push
* Otevrete si svuj github.com/VASLOGIN/prvniblog a overte, ze tam jsou zdrojaky
* Prihlaste se do https://www.pythonanywhere.com/
* Otevrit bash konzoli a tam
!PyA.com! git clone https://github.com/<your-github-username>/prvniblog.git
!PyA.com! tree prvniblog
!PyA.com! cd prvniblog
!PyA.com! virtualenv --python=python3.5 myvenv
!PyA.com! source myvenv/bin/activate
!PyA.com! pip install django
!PyA.com! python manage.py migrate
!PyA.com! python manage.py createsuperuser

* Vratit se do PyA a pridat web app (ne django, ale custom, cestu k venvu apod)

-- Virtualenv: --
/home/<your-PythonAnywhere-username>/prvniblog/myvenv/

-- WSGI configuration file: --
import os
import sys

path = '/home/<your-PythonAnywhere-username>/prvniblog'  # use your own PythonAnywhere username here
if path not in sys.path:
    sys.path.append(path)

os.environ['DJANGO_SETTINGS_MODULE'] = 'mysite.settings'

from django.core.wsgi import get_wsgi_application
from django.contrib.staticfiles.handlers import StaticFilesHandler
application = StaticFilesHandler(get_wsgi_application())

* zmacknout tlacitko nahore "Reload"

* JEDE NAM SAJTA! NA INTERNETU!

URLS
====

* Co je URL

! cat mysite/urls.py

! Pridat 
  from django.conf.urls import url, include

  url(r'', include('blog.urls')),

! -- blog/urls.py
from django.conf.urls import url
from . import views

urlpatterns = [
    url(r'^$', views.post_list, name='post_list'),
]

* pustit runserver?

VIEWS
=====
! -- blog/views.py --
from django.shortcuts import render

def post_list(request):
    return render(request, 'blog/post_list.html', {})
    
* otevrit http://127.0.0.1:8000/

TEMPLATES
=========
! mkdir blog/templates
! mkdir blog/templates/blog
! -- blog/templates/blog/post_list.html --



* otevrit http://127.0.0.1:8000/
 (prazdno)
 
! -- blog/templates/blog/post_list.html --
<html>
    <h1>Muj blog</h1>
    <p>Funguje to!</p>
</html> 

* otevrit http://127.0.0.1:8000/

<html>
    <h1>Muj blog</h1>
    <p>Funguje to!</p>

    <h2>Prvni post</h2>
    <p>To vypada super</p>
    
</html> 
 
* otevrit http://127.0.0.1:8000/

DEPLOY!!
(git status, add, commit, push)
PyA.com pull, WEB tab reload


ORM
====

! python manage.py shell

[ explore ]
! from blog.models import Post
! Post.objects.all()
! Post.objects.first()
! Post.objects.create(title="Kuk z konzole", text="Ulozi se to?")
! Post.objects.all()
! Post.objects.get(title="Kuk z konzole")
! Post.objects.order_by('created_date')
! Post.objects.order_by('-created_date')

Dynamic templates
=================

-- blog/views.py --
from blog.models import Post

def post_list(request):
    posts = Post.objects.order_by('-created_date')
    return render(request, 'blog/post_list.html', {'posts': posts})

! -- blog/templates/blog/post_list.html --
<html>
    <h1>Muj blog</h1>
    <p>Funguje to!</p>

    <h2>Prvni post</h2>
    <p>To vypada super</p>

    {{ posts }}
</html> 

! -- blog/templates/blog/post_list.html --
<html>
    <h1>Muj blog</h1>
    <p>Funguje to!</p>

    {% for post in posts %}
        <h2>{{ post.title }}</h2>
        <p>{{ post.text }}</p>
    {% endfor %}
</html> 

co chceme udelat:
blog
deploynout
...


slozitosti:
vysvetlovani regex v urls.py

via http://collabedit.com/ss4b5