完成评论功能

1. 定义评论的视图函数
   @app.route('/comment/',methods=['POST'])
   def comment()：
   读取前端页面数据，保存到数据库中
2. 用<input type="hidden" 方法获取前端的"question_id" 
3. 显示评论次数
4. 要求评论前登录
5. 尝试实现详情页面下的评论列表显示

 

 

from flask import Flask,render_template,request,redirect,url_for,session
from flask_sqlalchemy import SQLAlchemy
from functools import wraps
from datetime import datetime
import config
app = Flask(__name__)
app.config.from_object(config)
db=SQLAlchemy(app)
class User(db.Model):
    __tablename__ = 'user'
    id = db.Column(db.Integer,primary_key=True,autoincrement=True)
    username = db.Column(db.String(20),nullable=False)
    password = db.Column(db.String(20),nullable=False)
    nickname = db.Column(db.String(50))

class Question(db.Model):
    __tablename__ = 'question'
    id = db.Column(db.Integer,primary_key=True,autoincrement=True)
    title = db.Column(db.String(100),nullable=False)
    detail = db.Column(db.Text,nullable=False)
    creat_time = db.Column(db.DateTime,default=datetime.now)
    author_id = db.Column(db.Integer,db.ForeignKey('user.id'))
    author = db.relationship('User',backref=db.backref('question'))

class Comment(db.Model):
    __tablename__='comment'
    id = db.Column(db.Integer, primary_key=True, autoincrement=True)
    author_id = db.Column(db.Integer, db.ForeignKey('user.id'))
    question_id = db.Column(db.Integer, db.ForeignKey('question.id'))
    detail = db.Column(db.Text, nullable=False)
    creat_time = db.Column(db.DateTime, default=datetime.now)
    question = db.relationship('Question', backref=db.backref('comments',order_by=creat_time.desc))
    author = db.relationship('User', backref=db.backref('comments'))

db.create_all()


@app.route('/')
def shouye():
    context = {
        'questions': Question.query.all()
    }
    return render_template('shouye.html', **context)

@app.route('/denglu/',methods=['GET','POST'])
def gg():
    if request.method == 'GET':
        return render_template('denglu.html') #跳转登录
    else:
        usern = request.form.get('username')
        passw = request.form.get('password')
        user = User.query.filter(User.username == usern).first()
        if user:
            if user.password == passw:
                session['user'] = usern
                session.parmanent = True
                return redirect(url_for('shouye'))
            else:
                return u'password error'
        else:
            return u'username is not existed'

@app.route('/zhuche/', methods=['GET','POST'])
def login ():
    if request.method =='GET':
        return render_template('zhuce.html')#跳转注册
    else:
        usern = request.form.get('username')
        passw = request.form.get('password')
        nickn = request.form.get('nickname')
        user = User.query.filter(User.username == usern).first()
        if user:
            return u'username existed'
        else:
            user1 = User(username = usern,password = passw,nickname=nickn)
            db.session.add(user1)#数据库操作
            db.session.commit()
            return redirect(url_for('gg'))

@app.route('/tupian/')
def hh():
    return render_template('tupian.html') #跳转图片库

def loginFirst(func):
    @wraps(func)
    def wrapper (*args,**kwargs):
        if session.get('user'):
            return  func(*args,**kwargs)
        else:
            return redirect(url_for('gg'))
    return wrapper

@app.route('/xiangqing/<question_id>')
def xiangqing(question_id):
    quest = Question.query.filter(Question.id == question_id).first()
    return render_template('xiangqing.html',ques = quest)

@app.route('/comment',methods=['POST'])
@loginFirst
def comment():
    comment =request.form.get('new_comment')
    ques_id =request.form.get('question_id')
    auth_id =User.query.filter(User.username == session.get('user')).first().id
    comm = Comment(author_id=auth_id,question_id=ques_id,detail=comment)
    db.session.add(comm)
    db.session.commit()
    return redirect(url_for('xiangqing',question_id=ques_id))

@app.route('/fabu/',methods=['GET','POST'])
@loginFirst
def fabu():
    if request.method == 'GET':
        return render_template('fabu.html')
    else:
        title = request.form.get('title')
        detail = request.form.get('detail')
        author_id = User.query.filter(User.username == session.get('user')).first().id
        question = Question(title=title, detail=detail, author_id=author_id)
        db.session.add(question)
        db.session.commit()
    return redirect(url_for('shouye')) # 跳转发布

@app.context_processor
def context():
    usern = session.get('user')
    if usern:
        return {'username': usern }
    else:
        return {}

@app.route('/logout/')
def logout():
    session.clear()
    return redirect(url_for('shouye'))

if __name__ == '__main__':
    app.run(debug=True)

{% extends 'base.html' %}

{% block xiangqingtitle %}详细问答{% endblock %}
{% block xiangqinghead %}
<link href="../static/css/xiangqing.css" rel="stylesheet" type="text/css">
{% endblock %}
{% block xiangqingbody %}
<div class="card" style="width:50rem; margin:0 auto">

         <h1>详细问答</h1>

        <li class="list-group-item" >
            <span class="icon" aria-hidden="true"></span>
            <br>
            <a href="#">标题:{{ ques.title }}</a>
            <br>
            <a href="#">用户名:{{ ques.author.username}}</a>
             <span class="badge"style="float:right">{{ ques.creat_time}}</span>
        </li>
         <li class="list-group-item" style="height: 10rem" >
            <p>{{ ques.detail }}</p>
         </li>
        <form action="{{ url_for('comment') }}"method="post" >
            <div class="form-group">
                <textarea name="new_comment" class="form-control" rows="5" id="comment"
                              placeholder="请输入评论"></textarea>
                <input name="question_id" type="hidden" value="{{ ques.id }}"/>
            </div>
                <button type="submit" >发送</button>
        </form>
      <li class="list-group-item"style="height:3rem">最新评论:({{ ques.comments|length }})</li>

        <ul class="list-group"style="height: 50rem">
        {% for foo in ques.comments %}
            <li class="list-group-item">
                <span class="glyphicon" glyphicon-leaf aria-hidden="true"></span>
                <a href="#">用户名:{{ foo.author.username }}</a>
                <br>
                <a href="{{ url_for('xiangqing',question_id = foo.id) }}">标题:{{ foo.title }}</a>
                <span class="badge">{{ foo.creat_time }}</span>
                <br>
                <p class="neirong">内容:{{ foo.detail }}</p>
            </li>
        {% endfor %}
         </ul>

</div>

{% endblock %}