flask web开发实战 入门进阶和原理解析

import os
from flask import Flask, render_template, flash, redirect, url_for, Markup

app = Flask(__name__)
app.secret_key = os.getenv(‘SECRET_KEY‘, ‘secret string‘)


user = {
    ‘username‘: ‘dairuiquan‘,
    ‘bio‘: ‘ A boy who love  basketball and movies‘,
}

movies = [
    {‘name‘: ‘My Neighbor Totoro‘, ‘year‘: ‘1988‘},
    {‘name‘: ‘Three Colours trilogy‘, ‘year‘: ‘1993‘},
    {‘name‘: ‘Forrest Gump‘, ‘year‘: ‘1994‘},
    {‘name‘: ‘Perfect Blue‘, ‘year‘: ‘1997‘},
    {‘name‘: ‘The Matrix‘, ‘year‘: ‘1999‘},
    {‘name‘: ‘Memento‘, ‘year‘: ‘2000‘},
    {‘name‘: ‘The Bucket list‘, ‘year‘: ‘2007‘},
    {‘name‘: ‘Black Swan‘, ‘year‘: ‘2010‘},
    {‘name‘: ‘Gone Girl‘, ‘year‘: ‘2014‘},
    {‘name‘: ‘CoCo‘, ‘year‘: ‘2017‘},
]


@app.route(‘/watchlist‘)
def watchlist():
    return render_template(‘watchlist.html‘, user=user, movies=movies)


@app.route(‘/‘)
def index():
    name = ‘abc‘
    return render_template(‘index.html‘, name=name)


# 注册模版上下文处理函数，如果所有模版都需要传入相同变量，调用这个视图函数
@app.context_processor
def inject_info():
    foo = ‘I am a foo‘
    return dict(foo=foo)


# 注册模版全局函数
@app.template_global()
def bar():
    return ‘I am a bar‘


# 自定义过滤器  &#9835是html的音符图标的转义，这个过滤器接受一个参数，返回
# 参数加上音符图标
@app.template_filter()
def musical(s):
    return s + Markup(‘♫‘)


# 自定义测试器
@app.template_test()
def baz(n):
    if n == ‘baz‘:
        return True
    else:
        return False


@app.route(‘/watchlist2‘)
def watchlist_with_static():
    return render_template(‘watchlist_with_static.html‘, user = user, movies = movies)


@app.route(‘/flash‘)   # 定义闪现消息，闪现消息会显示在return的页面上
def just_flash():
    flash(‘I am flash, who is looking for me?‘)
    return redirect(url_for(‘index‘))  # flash消息显示在根目录


# 两个错误处理函数
@app.errorhandler(404)
def page_not_found(e):  # 这个传入的e是错误
    return render_template(‘errors/404.html‘), 404


@app.errorhandler(500)
def internal_server_error(e):
    return render_template(‘errors/500.html‘), 500

{% extends ‘base.html‘ %}
{% from ‘macros.html‘ import qux %}

{% block content %}
{% set name=‘baz‘ %}
<h1> Template</h1>
<ul>
    <li><a href="{{ url_for(‘watchlist‘) }}" >Watchlist </a></li>
    <li>Filter: {{ foo|musical }} </li>
    <li>Global: {{ bar() }}</li>
    <li>Test: {% if name is baz %} I am baz. {% endif %}</li>
    <li>Macro: {{ qux(amount = 5) }}</li>
    <li><a href="{{ url_for(‘watchlist_with_static‘) }}">Watchlist with image and styles.</a></li>
    <li><a href="{{ url_for(‘just_flash‘) }}">Flash something</a></li>

</ul>

{% endblock %}

{% block head %} {% block styles %} {% endblock %} {% endblock %}
Home
{% for message in get_flashed_messages() %}
{{ message }}
{% endfor %} {% block content %}{% endblock %}
{% block footer %} © 2018 Grey Li / GitHub / HelloFlask {% endblock %}
{% block scripts %}{% endblock %}