# flask2

**Repository Path**: hcfox/flask2

## Basic Information

- **Project Name**: flask2
- **Description**: No description available
- **Primary Language**: Python
- **License**: MIT
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2016-06-03
- **Last Updated**: 2020-12-19

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

#flask2

## 安装
1. ```sudo apt-get install python-virtualenv```
    ``` virtaulenv venv ```
2. ``` source ~/.venv/python3.5/bin/activiate ``` 激活py3.5环境
3. ``` pip install flask ``` 安装flask
4. jinja2 模板
    在controller里面通过 ``` render_template("模板文件",key=value) ``` 渲染模板
    模板默认在templates目录中
5.  Bootstrap
    ``` pip install flask-bootstrap ```
    引用 ``` from flask.ext.bootstrap import Bootstrap ``` 引用
    ```
    app = Flask(__name__)
    bootstrap = Bootstrap(app)
    ```
    页面中通过模板继承的方式使用
    ```
    {% extends "bootstrap/base.html" %}
    {% block content %}
    <div class="container">
        <div class="container">
            {% for message in get_flashed_messages()%}
            <div class="alert alert-warning">
                <button class="close" data-dismiss="alert">&times;</button>
                {{ message }}
            </div>
            {% endfor %}
        </div>
        {% block page_content %}{% endblock %}
    </div>
    {% endblock %}
    ```
    可以自定义自己的base.html并继承自bootstrap的base.html
    需要加入自定义的js文件可以这样
    ```
    { % block scripts % }
    {{ super() }}
    <script type="text/javascript" src="my-script.js"></script>
    { % endblock % }
    ```
    页面中通过url_for辅助函数生成链接地址，或者引用静态文件
    ```
    { % block head % }
    {{ super() }}
    <link rel="shortcut icon" href="{{ url_for('static', filename = 'favicon.ico') }}" type="image/x-icon">
    <link rel="icon" href="{{ url_for('static', filename = 'favicon.ico') }}" type="image/x-icon">
    { % endblock % }
    ```

6. Moment时间插件
    ``` pip install flask-moment ```
    应用
    ```
    from flask.ext.moment import Moment
    moment = Moment(app)
    ```
    页面中加入moment脚本
    ```
    {% block scripts %}
        {{super()}}
        {{ moment.include_moment() }}
    {% endblock %}
    ```
    使用
    ```
    <p>本地时间 {{ moment(current_time).format('LLL') }}</p>
    <p>距离 {{ moment(current_time).fromNow(refresh=True) }}</p>
    ```
7. 表单
    ``` pip install flask-wtf ```
    配置
    ``` app.config['SECRET_KEY'] = 'hard to guess string' ```
    表单类
    ```
    class NameForm(Form):
        name = StringField('你的姓名',validators = [ Required()])
        submit = SubmitField('提交')
    ```
    使用
    ```
    @app.route('/',methods=['GET','POST'])
    def index():
    name = None
        form = NameForm()
        if form.validate_on_submit():
            old_name = session.get('name')
            if old_name is not None and old_name != form.name.data:
    ```
8. 重定向
    ``` redirect(url_for('index')) ```

9. Flash消息
    ``` from flask import Flask, flash ```
    controller类中使用
    ``` flash('Looks like you have changed your name!') ```
    页面中显示
    ```
            {% for message in get_flashed_messages()%}
            <div class="alert alert-warning">
                <button class="close" data-dismiss="alert">&times;</button>
                {{ message }}
            </div>
            {% endfor %}
    ```

10. 数据库
    ``` pip install flask-sqlalchemy ```
    系统需要安装mysql 驱动 ``` apt-get install python-msyql ```
    配置
    ```
    app.config['SQLALCHEMY_DATABASE_URI'] = 'mysql+pymysql://root:1@127.0.0.1/test'
    app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = True
    app.config['SECRET_KEY'] = 'secret'
    db = SQLAlchemy(app)
    ```
    定义映射类
    ```
    class Role(db.Model):
        __tablename__ = 'roles'
        id = db.Column(db.Integer,primary_key=True)
        name = db.Column(db.String(64),unique=True)
        users = db.relationship('User',backref='role')

        def __repr__(self):
            return '<Role %r>' % self.name
    ```
    定义完模型可以可以进入ipython，进行数据库的建立和操作
    ```
    >>> from hello import db
    >>> db.create_all()
    >>> from hello import Role, User
    >>> admin_role = Role(name='Admin')
    >>> db.session.add(admin_role)
    >>> db.session.commit()
    >>> user_role = Role.query.filter_by(name='User').first()
    ```

11. Git更新学习
    - 在另外的电脑上
    ``` git clone https://git.oschina.net/hcfox/flask2.git ```
    下载，并 ``` cd flask2 ``` 进入相应的目录
    - 修改完成后通过
    ``` git commit -m "备注" . ``` 的方式，. 即代表当前目录以及所有子目录
    - 最后提交到服务器
    ```
    git push https://git.oschina.net/hcfox/flask2.git master
    ```