完成数据库的初步设计，连接成功，修改demo在modeified目录下的be备份中，不影响原有工作

figure_require/DB_struct_origin.drawio

@@ -0,0 +1,195 @@
+<mxfile host="65bd71144e">
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+                </mxCell>
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+                    <mxGeometry x="370" y="90" width="60" height="60" as="geometry"/>
+                </mxCell>
+                <mxCell id="31" value="&lt;font style=&quot;font-size: 13px&quot;&gt;store_id&lt;/font&gt;" style="ellipse;whiteSpace=wrap;html=1;fontFamily=Helvetica;fontSize=18;" vertex="1" parent="1">
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+                </mxCell>
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+                </mxCell>
+                <mxCell id="33" value="book_id" style="ellipse;whiteSpace=wrap;html=1;aspect=fixed;" vertex="1" parent="1">
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+                </mxCell>
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+                    <mxGeometry x="661" y="350" width="60" height="60" as="geometry"/>
+                </mxCell>
+                <mxCell id="35" value="stock_level" style="ellipse;whiteSpace=wrap;html=1;aspect=fixed;" vertex="1" parent="1">
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+                </mxCell>
+                <mxCell id="36" value="order_id" style="ellipse;whiteSpace=wrap;html=1;aspect=fixed;" vertex="1" parent="1">
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+                </mxCell>
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+                </mxCell>
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+                    <mxGeometry relative="1" as="geometry"/>
+                </mxCell>
+                <mxCell id="53" value="&lt;font style=&quot;font-size: 18px&quot;&gt;book&lt;/font&gt;" style="rounded=0;whiteSpace=wrap;html=1;fontFamily=Helvetica;fontSize=13;" vertex="1" parent="1">
+                    <mxGeometry x="620" y="520" width="120" height="60" as="geometry"/>
+                </mxCell>
+                <mxCell id="54" value="关于" style="rhombus;whiteSpace=wrap;html=1;fontFamily=Helvetica;fontSize=18;" vertex="1" parent="1">
+                    <mxGeometry x="510" y="490" width="80" height="80" as="geometry"/>
+                </mxCell>
+                <mxCell id="56" value="" style="endArrow=none;html=1;fontFamily=Helvetica;fontSize=18;exitX=1;exitY=1;exitDx=0;exitDy=0;entryX=0;entryY=0.5;entryDx=0;entryDy=0;" edge="1" parent="1" source="5" target="54">
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+                </mxCell>
+                <mxCell id="59" value="book_id" style="ellipse;whiteSpace=wrap;html=1;aspect=fixed;" vertex="1" parent="1">
+                    <mxGeometry x="767" y="450" width="60" height="60" as="geometry"/>
+                </mxCell>
+                <mxCell id="60" value="book_info" style="ellipse;whiteSpace=wrap;html=1;aspect=fixed;" vertex="1" parent="1">
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+                </mxCell>
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+                </mxCell>
+            </root>
+        </mxGraphModel>
+    </diagram>
+</mxfile>

modified/be/app.py

@@ -0,0 +1,4 @@
+import serve
+
+if __name__ == "__main__":
+    serve.be_run()

modified/be/creatTB.py

@@ -0,0 +1,5 @@
+from postgreSQLORM import Base,engine
+
+def createTable():
+    # 创建所有继承于Base的类对应的表
+    Base.metadata.create_all(engine)

modified/be/postgreSQLORM.py

@@ -0,0 +1,121 @@
+from sqlalchemy import create_engine,MetaData
+from sqlalchemy import Integer,String,ForeignKey,Column,TEXT
+from sqlalchemy.orm import relationship
+from sqlalchemy.ext.declarative import declarative_base
+from sqlalchemy.orm import sessionmaker
+from sqlalchemy import PrimaryKeyConstraint,UniqueConstraint
+import sqlalchemy
+Base=declarative_base()
+class con:
+    def connect():
+        '''Returns a connection and a metadata object'''
+        # We connect with the help of the PostgreSQL URL
+        
+        url = 'postgresql://stu10205501415:Stu10205501415@dase-cdms-2022-pub.pg.rds.aliyuncs.com:5432/stu10205501415'
+
+        # The return value of create_engine() is our connection object
+        con = create_engine(url, client_encoding='utf8')
+
+        # We then bind the connection to MetaData()
+        meta = MetaData(bind=con)
+
+        return con, meta
+
+
+class User(Base):
+    __tablename__ = 'user'
+    user_id = Column(TEXT, primary_key=True, comment="主键")
+    password = Column(TEXT, nullable=False, comment="密码")
+    balance = Column(Integer, nullable=False, comment="")
+    token = Column(TEXT, comment="缓存的令牌")
+    terminal = Column(TEXT, comment="终端代码")
+
+class Store(Base):
+    __tablename__ = 'store'
+    store_id = Column(TEXT, primary_key=True,comment="主键")
+    stock_level = Column(Integer, comment = "货存")
+
+class Store_Book(Base):
+    __tablename__ = 'store_book'
+    store_id = Column(TEXT, comment="主键")
+    book_id = Column(TEXT, comment="主键")
+    book_info = Column(TEXT, comment="书籍信息")
+    stock_level = Column(Integer, comment = "货存")
+
+    __table_args__ = (
+        PrimaryKeyConstraint('store_id', 'book_id'),
+    )
+
+class User_Store(Base):
+    __tablename__ = 'user_store'
+
+    id = Column(Integer, primary_key=True, autoincrement=True, comment="主键")
+
+    fk_user_id = Column(
+        TEXT,
+        ForeignKey(
+            "user.user_id",
+            ondelete="CASCADE",
+            onupdate="CASCADE",
+        ),
+        nullable=False,
+        comment="user外键"
+    )
+    fk_store_id = Column(
+        TEXT,
+        ForeignKey(
+            "store.store_id",
+            ondelete="CASCADE",
+            onupdate="CASCADE",
+        ),
+        nullable=False,
+        comment="store外键"
+    )
+    # 多对多关系的中间表必须使用联合唯一约束，防止出现重复数据
+    __table_args__ = (
+        UniqueConstraint("fk_user_id", "fk_store_id"),
+    )
+
+class New_Order(Base):
+    __tablename__ = 'new_order'
+    order_id = Column(TEXT, primary_key = True, comment = '订单id')
+    
+    fk_user_id = Column(
+        TEXT,
+        ForeignKey(
+            "user.user_id",
+            ondelete="CASCADE",
+            onupdate="CASCADE",
+        ),
+        nullable=False,
+        comment="user外键"
+    )
+    fk_store_id = Column(
+        TEXT,
+        ForeignKey(
+            "store.store_id",
+            ondelete="CASCADE",
+            onupdate="CASCADE",
+        ),
+        nullable=False,
+        comment="store外键"
+    )
+
+class New_Order_Detail(Base):
+    __tablename__ = 'new_order_detail'
+    order_id = Column(TEXT, comment='订单id')
+    book_id = Column(TEXT, comment='订单书籍')
+    count = Column(Integer, comment='购买书籍数')
+    price = Column(Integer, comment='单价')
+
+    __table_args__ = (
+        PrimaryKeyConstraint('order_id','book_id'),
+    )
+    
+engine, meta = con.connect()
+
+Base.metadata.bind = engine
+
+DBSession = sessionmaker(bind=engine)
+
+session = DBSession()

modified/be/serve.py

@@ -0,0 +1,12 @@
+from flask import Flask
+from flask import Blueprint
+from flask import request
+import testconn
+from creatTB import createTable
+
+
+def be_run():
+    app = Flask(__name__)
+    createTable()
+    app.register_blueprint(testconn.bp_testconn)
+    app.run(port=5000)

modified/be/testconn.py

@@ -0,0 +1,22 @@
+from flask import Blueprint
+from flask import Flask, abort, request, jsonify
+import json
+from flask import jsonify
+from sqlalchemy.ext.serializer import loads, dumps
+import postgreSQLORM
+from postgreSQLORM import User,Store,Store_Book,User_Store,New_Order,New_Order_Detail
+
+bp_testconn = Blueprint("testconn",__name__,url_prefix="/testconn")
+
+@bp_testconn.route("/test",methods=['GET'])
+def test():
+    user_id: str = request.args.get("user_id")
+    print(user_id)
+    try:
+        ss = postgreSQLORM.session.query(User).filter(User.user_id==user_id).all()
+        for i in ss:
+            print('user_id',i.user_id)
+    except:
+        print("error")
+    return "connect success"
+

report.md

@@ -0,0 +1,213 @@
+## <center> 华东师范大学数据科学与工程学院实验报告
+
+| **课程名称：当代数据库管理系统** |**年级** ：2020级 |**上机实践成绩**： |
+| --- | --- | --- |
+| **指导教师** ：高明 | **姓名** ：杨舜、姚嘉和 | **学号** ：10205501415、10205501436 |
+| **上机实践名称** ：BookStore ||**上机实践日期**：2022.11.28 —— 2022.12.10 |
+| **上机实践编号** ： | **组号 ：21** |**上机实践时间**：2022.11.28 —— 2022.12.10 |
+
+### 实验过程
+
+#### 一. 分析原有的数据库结构
+
+   分析demo中/be/model/store.py中创建数据库表的sql语句可知原有数据库的结构的ER图大致如下
+   ![avatar](./figure_require/DB_struct_origin.svg)
+
+   有上述ER图可以得到原有数据库表如下
+   
+   user表：
+   |user_id|password|balance|token|terminal|
+   |---|---|---|---|---|
+   主键为user_id
+
+   store表：
+   |store_id|stock_level|
+   |---|---|
+   主键为store_id
+   
+   store_book表：
+   |store_id|book_id|book_info|stock_level|
+   |---|---|---|---|
+   主键为联合主键(store_id,book_id)
+
+   user_store表：
+   |user_id|store_id|
+   |---|---|
+   外键为(user_id,store_id)
+
+   new_order表：
+   |order_id|user_id|store_id|
+   |---|---|---|
+   主键为（order_id）
+
+   new_order_detail表：
+   |oeder_id|book_id|count|price|
+   |---|---|---|---|
+   主键为联合主键(order_id,book_id)
+   
+   &nbsp;
+
+#### 二. 依据上述分析构建数据库table
+   1. 利用sqlalchemy连接远程的aliyun数据库并创建上述table [postgreSQLORM.py](./modified/be/postgreSQLORM.py)
+   ```python
+   class con:
+    def connect():
+        '''Returns a connection and a metadata object'''
+        # We connect with the help of the PostgreSQL URL
+        
+        url = 'postgresql://stu10205501415:Stu10205501415@dase-cdms-2022-pub.pg.rds.aliyuncs.com:5432/stu10205501415'
+
+        # The return value of create_engine() is our connection object
+        con = create_engine(url, client_encoding='utf8')
+
+        # We then bind the connection to MetaData()
+        meta = MetaData(bind=con)
+
+        return con, meta
+
+   class User(Base):
+     __tablename__ = 'user'
+    user_id = Column(TEXT, primary_key=True, comment="主键")
+    password = Column(TEXT, nullable=False, comment="密码")
+    balance = Column(Integer, nullable=False, comment="")
+    token = Column(TEXT, comment="缓存的令牌")
+    terminal = Column(TEXT, comment="终端代码")
+
+   class Store(Base):
+    __tablename__ = 'store'
+    store_id = Column(TEXT, primary_key=True,comment="主键")
+    stock_level = Column(Integer, comment = "货存")
+
+   class Store_Book(Base):
+    __tablename__ = 'store_book'
+    store_id = Column(TEXT, comment="主键")
+    book_id = Column(TEXT, comment="主键")
+    book_info = Column(TEXT, comment="书籍信息")
+    stock_level = Column(Integer, comment = "货存")
+
+    __table_args__ = (
+        PrimaryKeyConstraint('store_id', 'book_id'),
+    )
+
+   class User_Store(Base):
+    __tablename__ = 'user_store'
+
+    id = Column(Integer, primary_key=True, autoincrement=True, comment="主键")
+
+    fk_user_id = Column(
+        TEXT,
+        ForeignKey(
+            "user.user_id",
+            ondelete="CASCADE",
+            onupdate="CASCADE",
+        ),
+        nullable=False,
+        comment="user外键"
+    )
+    fk_store_id = Column(
+        TEXT,
+        ForeignKey(
+            "store.store_id",
+            ondelete="CASCADE",
+            onupdate="CASCADE",
+        ),
+        nullable=False,
+        comment="store外键"
+    )
+    # 多对多关系的中间表必须使用联合唯一约束，防止出现重复数据
+    __table_args__ = (
+        UniqueConstraint("fk_user_id", "fk_store_id"),
+    )
+
+   class New_Order(Base):
+    __tablename__ = 'new_order'
+    order_id = Column(TEXT, primary_key = True, comment = '订单id')
+    
+    fk_user_id = Column(
+        TEXT,
+        ForeignKey(
+            "user.user_id",
+            ondelete="CASCADE",
+            onupdate="CASCADE",
+        ),
+        nullable=False,
+        comment="user外键"
+    )
+    fk_store_id = Column(
+        TEXT,
+        ForeignKey(
+            "store.store_id",
+            ondelete="CASCADE",
+            onupdate="CASCADE",
+        ),
+        nullable=False,
+        comment="store外键"
+    )
+
+   class New_Order_Detail(Base):
+    __tablename__ = 'new_order_detail'
+    order_id = Column(TEXT, comment='订单id')
+    book_id = Column(TEXT, comment='订单书籍')
+    count = Column(Integer, comment='购买书籍数')
+    price = Column(Integer, comment='单价')
+
+    __table_args__ = (
+        PrimaryKeyConstraint('order_id','book_id'),
+    )
+    
+   engine, meta = con.connect()
+   Base.metadata.bind = engine
+   DBSession = sessionmaker(bind=engine)
+   session = DBSession()
+   ```
+   2. 在上述创建的table中添加初始数据并利用该数据测试后端服务器与数据库的连接
+   ![avatar](./figure_require/add_naive_userdata.png)
+   ![avatar](./figure_require/conn_test.png)
+   
+   3. 类比原有demo分别为不同的路由绑定不同的蓝图
+   ```python
+    app.register_blueprint(auth.bp_auth)
+    app.register_blueprint(seller.bp_seller)
+    app.register_blueprint(buyer.bp_buyer)
+   ```
+
+   4. 在/be/model目录下创建User类用书实现User对于数据库的一些交互功能
+   5. 修改[model/db_conn.py](./be/model/db_conn.py)中查询的操作为orm操作
+   ```python
+   from model import postgreSQLORM
+   from model.postgreSQLORM import User, Store_Book, User_Store
+
+   class DBConn:
+    def __init__(self):
+        return
+        # self.conn = store.get_db_conn()
+
+    def user_id_exist(self, user_id):
+        row = postgreSQLORM.session.query(User).filter(User.user_id==user_id).one()
+        # cursor = self.conn.execute("SELECT user_id FROM user WHERE user_id = ?;", (user_id,))
+        # row = cursor.fetchone()
+        if row is None:
+            return False
+        else:
+            return True
+
+    def book_id_exist(self, store_id, book_id):
+        row = postgreSQLORM.session.query(Store_Book).filter(Store_Book.book_id==book_id and Store_Book.store_id==store_id).one()
+        # cursor = self.conn.execute("SELECT book_id FROM store WHERE store_id = ? AND book_id = ?;", (store_id, book_id))
+        # row = cursor.fetchone()
+        if row is None:
+            return False
+        else:
+            return True
+
+    def store_id_exist(self, store_id):
+        row = postgreSQLORM.session.query(User_Store).filter(User_Store.fk_store_id==store_id).one()
+        # cursor = self.conn.execute("SELECT store_id FROM user_store WHERE store_id = ?;", (store_id,))
+        # row = cursor.fetchone()
+        if row is None:
+            return False
+        else:
+            return True
+
+   ```
+   6.