src/models/author.py

@@ -1,4 +1,4 @@
-from sqlalchemy import Column, Integer, String, TIMESTAMP, UniqueConstraint
+from sqlalchemy import Column, Integer, String
 from sqlalchemy.orm import relationship
 from sqlalchemy.ext.declarative import declarative_base
 
@@ -9,9 +9,9 @@ Base = declarative_base()
 
 class Author(Base):
     __tablename__ = 'author'
-    __table_args__ = (UniqueConstraint('id'),)
 
-    id           = Column(Integer, primary_key=True)
+    id = Column(Integer, primary_key=True, autoincrement=True)
     first_name = Column(String(50), nullable=False)
     last_name = Column(String(50), nullable=False)
-    last_updated = Column(TIMESTAMP, nullable=False, default='CURRENT_TIMESTAMP()')
+
+    books = relationship('Book', back_populates='author')

src/models/book.py

@@ -1,6 +1,4 @@
-import enum
-
-from sqlalchemy import Column, Integer, String, TIMESTAMP, Text, ForeignKey, Enum, UniqueConstraint
+from sqlalchemy import Column, Integer, String, TIMESTAMP, Text, ForeignKey, Enum
 from sqlalchemy.orm import relationship
 from sqlalchemy.ext.declarative import declarative_base
 
@@ -10,23 +8,21 @@ from .book_category import BookCategory
 Base = declarative_base()
 
 
-class BookStatusEnum(enum.Enum):
-    available = 'available'
-    borrowed = 'borrowed'
-    reserved = 'reserved'
-
 class Book(Base):
     __tablename__ = 'book'
-    __table_args__ = (UniqueConstraint('isbn'),)
 
-    id             = Column(Integer, primary_key=True)
-    author_id      = Column(Integer, ForeignKey('author.id'), nullable=False)
+    id = Column(Integer, primary_key=True, autoincrement=True)
+    author_id = Column(Integer, ForeignKey(
+        'author.id'), nullable=False, index=True)
     title = Column(String(100), nullable=False)
     description = Column(Text, nullable=False)
     year_published = Column(String(4), nullable=False)
     isbn = Column(String(13), nullable=False, unique=True)
-    status         = Column(Enum(BookStatusEnum), nullable=False, default=BookStatusEnum.available)
-    created_at     = Column(TIMESTAMP, nullable=False, default='CURRENT_TIMESTAMP()')
-    last_updated   = Column(TIMESTAMP, nullable=False, default='CURRENT_TIMESTAMP()')
+    status = Column(Enum('available', 'borrowed', 'reserved'),
+                    nullable=False, default='available')
+    created_at = Column(TIMESTAMP, nullable=True, default="CURRENT_TIMESTAMP")
 
-    author = relationship('Author', backref='books')
+    author = relationship('Author', back_populates='books')
+    # loans = relationship('Loan', back_populates='book')
+    categories = relationship(
+        'BookCategory', secondary='book_category_link', back_populates='books')

src/models/book_category.py

@@ -1,5 +1,5 @@
 from .book import Book
-from sqlalchemy import Column, Integer, String, TIMESTAMP, ForeignKey, UniqueConstraint
+from sqlalchemy import Column, Integer, String, TIMESTAMP, Text, ForeignKey, Enum
 from sqlalchemy.orm import relationship
 from sqlalchemy.ext.declarative import declarative_base
 
@@ -8,12 +8,12 @@ Base = declarative_base()
 
 class BookCategory(Base):
     __tablename__ = 'book_category'
-    __table_args__ = (UniqueConstraint('name'),)
 
-    id                 = Column(Integer, primary_key=True)
-    parent_category_id = Column(Integer, ForeignKey('book_category.id'), nullable=True)
-    name               = Column(String(100), nullable=False)
-    mature_content     = Column(Integer, nullable=False, default=0)
-    last_updated       = Column(TIMESTAMP, nullable=False, default='CURRENT_TIMESTAMP()')
+    id = Column(Integer, primary_key=True, autoincrement=True)
+    parent_category_id = Column(Integer, ForeignKey(
+        'book_category.id'), nullable=True, index=True)
+    name = Column(String(100), nullable=False, unique=True)
 
     parent_category = relationship('BookCategory', remote_side=[id])
+    books = relationship(
+        'Book', secondary='book_category_link', back_populates='categories')

src/models/book_category_link.py

@@ -1,18 +1,10 @@
 from sqlalchemy import Column, Integer, ForeignKey
-from sqlalchemy.orm import relationship
 from sqlalchemy.ext.declarative import declarative_base
 
-
-from .book import Book
-from .book_category import BookCategory
-
 Base = declarative_base()
 
 class BookCategoryLink(Base):
     __tablename__ = 'book_category_link'
 
-    book_id          = Column(Integer, ForeignKey('book.id'), primary_key=True)
-    book_category_id = Column(Integer, ForeignKey('book_category.id'), primary_key=True)
-
-    book          = relationship('Book', backref='categories')
-    book_category = relationship('BookCategory', backref='books')
+    book_id = Column(Integer, ForeignKey('book.id'), primary_key=True, index=True)
+    book_category_id = Column(Integer, ForeignKey('book_category.id'), primary_key=True, index=True)

src/models/librarian.py

@@ -1,32 +0,0 @@
-import enum
-
-from sqlalchemy import Column, Integer, String, TIMESTAMP, Text, ForeignKey, Enum, UniqueConstraint
-from sqlalchemy.orm import relationship
-from sqlalchemy.ext.declarative import declarative_base
-
-
-Base = declarative_base()
-
-
-class LibrarianStatusEnum(enum.Enum):
-    active   = 'active'
-    inactive = 'inactive'
-
-class LibrarianRoleEnum(enum.Enum):
-    staff = 'staff'
-    admin = 'admin'
-
-
-class Librarian(Base):
-    __tablename__  = 'librarian'
-    __table_args__ = (UniqueConstraint('id'),)
-
-    id           = Column(Integer, primary_key=True)
-    first_name   = Column(String(50), nullable=False)
-    last_name    = Column(String(50), nullable=False)
-    email        = Column(String(100), nullable=False, unique=True)
-    phone        = Column(String(20), nullable=False)
-    hire_date    = Column(TIMESTAMP, nullable=False, default='CURRENT_TIMESTAMP()')
-    status       = Column(Enum(LibrarianStatusEnum), nullable=False, default=LibrarianStatusEnum.active)
-    role         = Column(Enum(LibrarianRoleEnum), nullable=False)
-    last_updated = Column(TIMESTAMP, nullable=False, default='CURRENT_TIMESTAMP()')

src/models/loan.py

@@ -1,38 +0,0 @@
-import enum
-
-from sqlalchemy import Column, Integer, String, TIMESTAMP, Text, ForeignKey, Enum, UniqueConstraint, Float
-from sqlalchemy.orm import relationship
-from sqlalchemy.ext.declarative import declarative_base
-
-from .book import Book
-from .member import Member
-from .librarian import Librarian
-
-Base = declarative_base()
-
-
-class LoanStatusEnum(enum.Enum):
-    borrowed = 'borrowed'
-    returned = 'returned'
-    overdue  = 'overdue'
-    reserved = 'reserved'
-
-
-class Loan(Base):
-    __tablename__  = 'loan'
-    __table_args__ = (UniqueConstraint('id'),)
-
-    id           = Column(Integer, primary_key=True)
-    book_id      = Column(Integer, ForeignKey('book.id'), nullable=False)
-    member_id    = Column(Integer, ForeignKey('member.id'), nullable=False)
-    librarian_id = Column(Integer, ForeignKey('librarian.id'), nullable=False)
-    loan_date    = Column(TIMESTAMP, nullable=False, default='CURRENT_TIMESTAMP()')
-    due_date     = Column(TIMESTAMP, nullable=False)
-    return_date  = Column(TIMESTAMP, nullable=True)
-    status       = Column(Enum(LoanStatusEnum), nullable=False, default=LoanStatusEnum.borrowed)
-    overdue_fee  = Column(Float, nullable=True)
-    last_updated = Column(TIMESTAMP, nullable=False, default='CURRENT_TIMESTAMP()')
-
-    book      = relationship('Book', backref='loans')
-    member    = relationship('Member', backref='loans')
-    librarian = relationship('Librarian', backref='loans')

src/models/member.py

@@ -1,24 +0,0 @@
-import enum
-
-from sqlalchemy import Column, Integer, String, TIMESTAMP, Text, ForeignKey, Enum, UniqueConstraint
-from sqlalchemy.orm import relationship
-from sqlalchemy.ext.declarative import declarative_base
-
-class MemberStatusEnum(enum.Enum):
-    active = 'active'
-    inactive = 'inactive'
-
-Base = declarative_base()
-
-class Member(Base):
-    __tablename__  = 'member'
-    __table_args__ = (UniqueConstraint('id'),)
-
-    id            = Column(Integer, primary_key=True)
-    first_name    = Column(String(50), nullable=False)
-    last_name     = Column(String(50), nullable=False)
-    email         = Column(String(100), nullable=False, unique=True)
-    phone         = Column(String(20), nullable=True)
-    register_date = Column(TIMESTAMP, nullable=True, default='CURRENT_TIMESTAMP()')
-    status        = Column(Enum(MemberStatusEnum), nullable=True, default=MemberStatusEnum.active)
-    last_updated  = Column(TIMESTAMP, nullable=True)