django-tutorial

整个项目的目的是练习和实践一些内容，不作为实际工程参考。

App

mysite: main app
users: auth/users resource
chat: asgi application/websocket(removed, will be another project)
influxdb_plotly: read data from influxdb and plot by plotly
polls: official practice
mzitu: api (work with celery)

How-to-Use

local

choose apps you want to use in mysite/settings/base.py, comment the apps you do not want
virtualenv a python3 environment, then pip install -r requirements.txt
start app ./manage.py runserver
todo: package the frontend
access
- web 127.0.0.1:8000
- api 127.0.0.1:8000/api/{VERSION}/swagger/
flower celery flower -A mysite --address=127.0.0.1 --port=5555
celery
- celery -A mysite worker -l debug
- celery -A mysite beat -l debug
- with gevent celery -A mysite worker -l debug -P gevent -c 100

docker

frontend folder, npm run build
WHERE_Dockerfile run ./docker-development.sh
127.0.0.1:80

docker-compose scale

docker-compose up --scale celery-worker=2
- 接收多个服务参数

ORM

3 steps for models

write your models.py
python manage.py makemigrations [APP] (APP optional)
python manage.py migrate [APP] (APP optional)

查看migrations文件的操作，不会执行，打印他的SQL语句：

$ python manage.py sqlmigrate polls 0001

回退操作：

python manage.py migrate APP 0004_xxxxx(the migration name, number must)

一对多，多对多

 from django.db import models

class Reporter(models.Model):
    # ...
    pass

class Article(models.Model):
    reporter = models.ForeignKey(Reporter, on_delete=models.CASCADE)

上面的例子，reporter.article_set可以访问一个reporter关联的多个文章。

class Topping(models.Model):
   # ...
   pass

class Pizza(models.Model):
   toppings = models.ManyToManyField(Topping)

这个多对多的例子，方法可以作用于topping.pizza_set 以及pizza.toppings。

字段查找 field lookups

构建SQL的WHERE表达式时使用，作为QuerySet的fielter，exclude和get方法的参数。

格式：field__lookuptype=value，双下划线

>>> Entry.objects.filter(pub_date__lte='2006-01-01')

对应的SQL语句:

SELECT * FROM blog_entry WHERE pub_date <= '2006-01-01';

项目

检查项目问题，不会生成migrations也不会动数据库：

$ python manage.py check

交互shell

如果要使用ipython作为交互的terminal，并集成django的环境，先安装ipython。

$ python manage.py shell

In [3]: Question.objects.all()
Out[3]: <QuerySet [<Question: What's up?>]>

In [4]: Question.objects.filter(question_text__startswith='What')
Out[4]: <QuerySet [<Question: What's up?>]>

Apache ab test

example:

ab -c 10 -n 40 http://127.0.0.1:8000/api/v1/mzitu/tags/

26huitailang/django-tutorial