Flask接口设计和数据库设计
1、技术概述，描述这个技术是做什么？学习该技术的原因，技术的难点在哪里。
使用Flask框架进行程序后端的接口设计和数据库，之所以学习是为了完成团队项目中后端笔记部分的接口，难点是之前为接触过Flask，学习起来有一定难度，对路由和ORM等不了解。
2、技术详述，描述你是如何实现和使用该技术的，要求配合代码和流程图详细描述。
- 1、先建note.py文件到时在里面写路由。
import json
import os
from datetime import datetime
from flask import Blueprint,request,current_app,send_from_directory
from flask_login import current_user,login_user,logout_user
from ..models.note import Note,File,Compliments
from ..extensions import db
from ..models.user import User
from ..utils import random_filename
note_bp = Blueprint('note',__name__)
@note_bp.before_request #!@#!@#
def login_project():
route = ['avatar','file']
method = request.method
ext = request.path
flag = False
for i in route :
if i in ext :
flag = True
if method == 'GET' and flag :
pass
else :
result = {}
if current_user.is_authenticated == False:
result['code'] = -1
result['msg'] = '您当前未登录！'
return json.dumps(result)
else :
id =current_user.get_id()
user = User.query.get(id)
if user.is_verify == False and user.is_admin == False:
result['code'] = -2
result['msg'] = '请先实名制认证！'
return json.dumps(result)
@note_bp.route('',methods=['POST'])
def release():
results = {}
data = {}
title = request.form.get('title')
tag = request.form.get('tag')
content = request.form.get('content')
uid = int(current_user.get_id())
note = Note(
title = title,
tag = tag,
content = content,
note_date = datetime.today(),
user_id = uid
)
db.session.add(note)
db.session.commit()
data['id'] = note.id
results['code'] = 0
results['msg'] = '发布成功'
results['data'] = data
return json.dumps(results)
@note_bp.route('/published',methods=['GET'])
def my_published():
results = {}
data = []
id = int(current_user.get_id())
notes = Note.query.filter_by(user_id=id).order_by(Note.note_date.desc()).all()
if notes != None :
for item in notes:
flag = True
cc = Compliments.query.filter_by(note_id=item.id, user_id=id).first()
if cc is None:
flag = False
d = {
"note_id" : item.id,
"title" : item.title,
"tag" : item.tag,
"content" : item.content[0:32] + '...' ,
"compliments" : item.compliments,
"flag" : flag,
"note_date" : item.note_date.strftime('%Y-%m-%d'),
}
data.append(d)
results['code'] = 0
results['msg'] = 'success'
results['data'] = data
return json.dumps(results)
@note_bp.route('/search',methods=['GET'])
def search():
results = {}
Data = []
data = []
word = str(request.args.get('word'))
notes = Note.query.order_by(Note.note_date.desc()).all()
if word != None:
words = word.split(' ')
for i in words:
for note in notes:
if i in note.tag:
if note not in Data:
flag = True
cc = Compliments.query.filter_by(note_id=note.id, user_id=current_user.id).first()
if cc is None :
flag = False
d = {
"publisher_id": note.user_id,
'publisher_nickname': note.user.nickname,
'note_id' : note.id,
'title': note.title,
'tag': note.tag,
'content': note.content,
"note_date": note.note_date.strftime('%Y-%m-%d'),
"compliments" : note.compliments,
"flag" : flag
}
Data.append(note)
data.append(d)
results['code'] = 0
results['msg'] = "查找成功"
results['data'] = data
return json.dumps(results)
@note_bp.route('/',methods=['GET'])
def note(id):
results = {}
note = Note.query.get(id)
flag = True#current_user.id
cc = Compliments.query.filter_by(note_id=id, user_id=current_user.id).first()
if cc is None:
flag = False
data = {
"publisher_id" : note.user_id,
"title" : note.title,
"tag" : note.tag,
"content" : note.content,
"note_date" : note.note_date.strftime('%Y-%m-%d'),
"compliments" : note.compliments,
"flag" : flag
}
results['code'] = 0
results['msg'] = '查看成功'
results['data'] = data
return json.dumps(results)
@note_bp.route('/upload',methods=['POST'])
def upload():
results = {}
f = request.files.get('file')
filename = random_filename(f.filename)
f.save(os.path.join(current_app.config['FILE_PATH'], filename))
file = File(
filename=filename
)
db.session.add(file)
db.session.commit()
data = {
"file_id":file.id
}
results['code'] = 0
results['msg'] = '上传成功'
results['data'] = data
return json.dumps(results)
@note_bp.route('/file/',methods=['GET'])
def get_file(id):
file = File.query.get(id)
filename = file.filename
return send_from_directory(current_app.config['FILE_PATH'], filename)
@note_bp.route('/categories',methods=['GET'])
def categories():
results = {}
data = []
notes = Note.query.all()
for note in notes :
if note.tag not in data:
data.append(note.tag)
results['code'] = 0
results['msg'] = 'success'
results['data'] = data
return json.dumps(results)
@note_bp.route('/index',methods=['GET'])
def index():
results={}
data = []
tag = request.args.get('tag')
page = int(request.args.get('page'))
each_page = int(request.args.get('each_page'))
length = Note.query.filter_by(tag=tag).count()
pagination = Note.query.filter_by(tag=tag).order_by(Note.note_date.desc()).paginate(page,per_page=each_page)
notes = pagination.items
for note in notes :
flag = True
cc = Compliments.query.filter_by(note_id=note.id, user_id=current_user.id).first()
if cc is None:
flag = False
d = {}
d["publisher_id"] = note.user_id
d["publisher_nickname"] = note.user.nickname
d["note_id"] = note.id
d["title"] = note.title
d["content"] = note.content[0:32] +'...'
d["note_date"] = note.note_date.strftime('%Y-%m-%d')
d["compliments"] = note.compliments
d['flag'] = flag
data.append(d)
results['code'] = 0
results['msg'] = '返回成功'
results['data'] = data
results['length'] = length
return json.dumps(results)
@note_bp.route('/edit',methods=['POST'])
def edit():
results = {}
id = request.form.get('note_id')
content = request.form.get('content')
note = Note.query.get(id)
note.content = content
note.note_date = datetime.today()
db.session.commit()
results['code'] = 0
results['msg'] = '修改成功'
return json.dumps(results)
@note_bp.route('/compliments',methods=['POST'])
def compliments():
results = {}
id = request.form.get('note_id')
uid = current_user.id
cc = Compliments.query.filter_by(note_id=id, user_id=uid).first()
if cc != None :
results['code'] = 1
results['msg'] = '你已经点过赞了'
return json.dumps(results)
c = Compliments(
note_id = id,
user_id = uid
)
note = Note.query.get(id)
note.compliments += 1
db.session.add(c)
db.session.commit()
results['code'] = 0
results['msg'] = '点赞成功'
return json.dumps(results)
@note_bp.route('/recomp',methods=['POST'])
def recomp():
results = {}
id = request.form.get('note_id')
uid = current_user.id
c = Compliments.query.filter_by(note_id = id,user_id = uid).first()
note = Note.query.get(id)
note.compliments -= 1
db.session.delete(c)
db.session.commit()
results['code'] = 0
results['msg'] = '取消点赞成功'
return json.dumps(results)
- 2、在modules里建notes.py。
from ..extensions import db
from ..models.user import User
class Note(db.Model):
id = db.Column(db.Integer, primary_key=True)
title = db.Column(db.String(32), nullable=False) # 标题
compliments = db.Column(db.Integer, default=0) # 点赞数
note_date = db.Column(db.TIMESTAMP, nullable=False) # 笔记最近一次更新时间
tag = db.Column(db.String(32),nullable=False)
content = db.Column(db.Text)
user_id = db.Column(db.Integer, db.ForeignKey('user.id')) #谁发布的
user = db.relationship('User', back_populates='notes') # 用户
comps = db.relationship('Compliments', back_populates='note')
class File(db.Model):
id = db.Column(db.Integer, primary_key=True)
filename = db.Column(db.String(128),nullable=False,unique=True)
class Compliments(db.Model):
id = db.Column(db.Integer, primary_key=True)
user_id = db.Column(db.Integer, db.ForeignKey('user.id')) # 谁点赞的
note_id = db.Column(db.Integer, db.ForeignKey('note.id')) # 谁点赞的
note = db.relationship('Note', back_populates='comps') # 用户
user = db.relationship('User', back_populates='comps') # 用户
- 3、根据数据库设计用ORM实现即可。
3、技术使用中遇到的问题和解决过程。
刚刚开始的时候对路由的概念不了解，所以先进行了学习，使用的书是《Flask Web开发：Python基于Web应用开发实战 第 2 版 》关于路由的定义
@app.route('/user/')
def user(name):
return 'Hello, {}!
'.format(name)
了解之后直接就可以上手了，比较简单，数据库使用时碰到的问题是在使用db.create_all() 时出现了一些问题，原因是一些表已经存在了，但是使用它时不会重新创建或者更新相应的表，于是我先删除旧表再重新创建，然后就一切顺利
>>> db.drop_all()
>>> db.create_all()
4、进行总结
初学的时候感觉压力很大，因为时间赶，加上我觉得它难度比较大，后面逼着自己学习才发现这个技术还是比较简单的，中间碰到的问题通过百度和电子书查看实例都能够解决，所以说不要去害怕学习新的知识，只要用心打的去学习了，就会有收获。
5、列出参考文献、参考博客（标题、作者、链接）。
《Flask Web开发：Python基于Web应用开发实战 第 2 版 》
Flask中路由使用解析