使用 Flask 开发博客
Flask 是一个轻量级的 Web 框架,适合小型应用和学习项目。我们将通过 Flask 开发一个简单的博客系统,支持用户注册、登录、发布文章等功能。
步骤:
安装 Flask 和其他必要库:
在开发博客之前,首先需要安装 Flask。可以使用
pip
安装 Flask 和其他依赖:pip install Flask Flask-SQLAlchemy Flask-WTF Flask-Login email-validator
项目结构:
项目结构如下:
/blog /templates base.html create_post.html edit_post.html index.html layout.html login.html register.html post.html /static /css style.css app.py models.py forms.py
创建数据库模型 (models.py):
使用 Flask 的 SQLAlchemy 扩展来进行数据库操作。我们首先定义用户和文章的数据库模型。
# models.py
from flask_sqlalchemy import SQLAlchemy
from datetime import datetime # 导入 datetime
from flask_login import UserMixin
db = SQLAlchemy()
class User(UserMixin, db.Model):
id = db.Column(db.Integer, primary_key=True)
username = db.Column(db.String(80), unique=True, nullable=False)
email = db.Column(db.String(120), unique=True, nullable=False)
password = db.Column(db.String(120), nullable=False)
date_registered = db.Column(db.DateTime, default=datetime.utcnow)
is_active = db.Column(db.Boolean, default=True) # 默认值设置为True,表示用户激活
def get_id(self):
return str(self.id) # 或者返回其他唯一标识符,如 email 等
posts = db.relationship('Post', back_populates='user', lazy=True)
class Post(db.Model):
id = db.Column(db.Integer, primary_key=True)
title = db.Column(db.String(100), nullable=False)
content = db.Column(db.Text, nullable=False)
date_posted = db.Column(db.DateTime, default=datetime.utcnow)
# 外键关联用户表
user_id = db.Column(db.Integer, db.ForeignKey('user.id'), nullable=False)
# 修改 backref 名称,避免与 User 模型中的属性冲突
user = db.relationship('User', back_populates='posts')
def __init__(self, title, content, user):
self.title = title
self.content = content
self.user = user # author 参数应该作为 user
创建 Flask 应用 (app.py):
在
app.py
中初始化 Flask 应用,配置数据库,处理用户请求和路由。
# app.py
from flask import Flask, render_template, url_for, redirect, request, flash
from models import db, User, Post
from flask_login import LoginManager, login_user, login_required, current_user, logout_user
from forms import RegistrationForm, LoginForm, PostForm
from datetime import datetime
app = Flask(__name__)
app.config['SECRET_KEY'] = '123456'
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///site.db'
db.init_app(app)
with app.app_context():
db.create_all() # 创建数据库表
login_manager = LoginManager(app)
login_manager.login_view = 'login'
@login_manager.user_loader
def load_user(user_id):
return db.session.get(User, int(user_id))
@app.route('/')
def index():
posts = Post.query.all()
print(current_user.is_authenticated)
return render_template('index.html', posts=posts)
@app.route('/register', methods=['GET', 'POST'])
def register():
form = RegistrationForm()
if form.validate_on_submit():
user = User(username=form.username.data, email=form.email.data, password=form.password.data)
db.session.add(user)
db.session.commit()
flash('Your account has been created!', 'success')
return redirect(url_for('login'))
return render_template('register.html', form=form)
@app.route('/login', methods=['GET', 'POST'])
def login():
form = LoginForm()
if form.validate_on_submit():
user = User.query.filter_by(username=form.username.data).first()
if user and user.password == form.password.data:
login_user(user)
return redirect(url_for('index'))
else:
flash('Login Unsuccessful. Please check username and password', 'danger')
return render_template('login.html', form=form)
@app.route('/logout')
def logout():
logout_user()
return redirect(url_for('index'))
@app.route('/post/new', methods=['GET', 'POST'])
@login_required
def new_post():
form = PostForm()
if form.validate_on_submit():
post = Post(title=form.title.data, content=form.content.data, user=current_user)
db.session.add(post)
db.session.commit()
flash('Your post has been created!', 'success')
return redirect(url_for('index'))
return render_template('create_post.html', title='New Post', form=form)
@app.route("/post/<int:post_id>")
def post(post_id):
post = Post.query.get_or_404(post_id)
return render_template('post.html', post=post)
@app.route('/post/edit/<int:post_id>', methods=['GET', 'POST'])
@login_required
def edit_post(post_id):
post = Post.query.get_or_404(post_id)
# 确保只能编辑自己的博客
if post.user != current_user:
flash('You cannot edit this post.', 'danger')
return redirect(url_for('index'))
form = PostForm()
if form.validate_on_submit():
post.title = form.title.data
post.content = form.content.data
db.session.commit()
flash('Your post has been updated!', 'success')
return redirect(url_for('index'))
# 使用现有的博客数据填充表单
elif request.method == 'GET':
form.title.data = post.title
form.content.data = post.content
return render_template('edit_post.html', title='Edit Post', form=form, post=post)
@app.route("/post/delete/<int:post_id>", methods=["Get", `"POST"])
def delete_post(post_id):
post = Post.query.get_or_404(post_id)
db.session.delete(post)
db.session.commit()
flash("Post has been deleted!", "success")
return redirect(url_for('index')) # 或者返回其他页面
if __name__ == '__main__':
app.run(debug=True)
创建表单 (forms.py):
使用 Flask-WTF 扩展来创建用户注册、登录和文章发布的表单。
# forms.py
from flask_wtf import FlaskForm
from wtforms import StringField, PasswordField, TextAreaField
from wtforms.validators import DataRequired, Length, Email, EqualTo
class RegistrationForm(FlaskForm):
username = StringField('Username', validators=[DataRequired(), Length(min=2, max=20)])
email = StringField('Email', validators=[DataRequired(), Email()])
password = PasswordField('Password', validators=[DataRequired()])
confirm_password = PasswordField('Confirm Password', validators=[DataRequired(), EqualTo('password')])
class LoginForm(FlaskForm):
username = StringField('Username', validators=[DataRequired()])
password = PasswordField('Password', validators=[DataRequired()])
class PostForm(FlaskForm):
title = StringField('Title', validators=[DataRequired()])
content = TextAreaField('Content', validators=[DataRequired()])
创建模板 (HTML):
在
templates
文件夹中,创建 HTML 模板来展示博客页面。<!-- index.html --> {% extends 'base.html' %} {% block content %} <h1>Blog Posts</h1> <ul> {% for post in posts %} <li> <h2>{{ post.title }}</h2> <p>{{ post.content }}</p> <p><small>Posted on {{ post.date_posted }}</small></p> </li> {% endfor %} </ul> {% endblock %}
运行应用:
启动 Flask 应用:
python app.py
展示效果
上面最简单的博客就搭建完成了,但博主怎么能止步于此呢,进一步实现相关的html页面来进一步完善吧,尽请期待第二弹。
文学和科学相比,的确没什么用处,但文学最大的用处,也许就是它没有用处