Solution

crud.py

@@ -0,0 +1,65 @@
+from fastapi import Query
+from sqlalchemy import select
+from sqlalchemy.orm import Session
+
+import models
+from schemas import AuthorCreate, BookCreate
+
+
+def get_all_authors(
+    db: Session,
+    skip: int = Query(default=0, ge=0),
+    limit: int = Query(default=9, ge=1)
+    ):
+
+    return db.scalars(select(models.Author)).offset(skip).limit(limit).all()
+
+
+def get_author(
+    db: Session,
+    author_id: int
+):
+    return db.scalar(select(models.Author).where(models.Author.id == author_id))
+
+
+def create_author(db: Session, author: AuthorCreate):
+    db_author = models.Author(
+        name=author.name,
+        bio=author.bio,
+    )
+    db.add(db_author)
+    db.commit()
+    db.refresh(db_author)
+
+    return db_author
+
+
+def get_all_books(db: Session,
+    author_id: int | None = None,
+    skip: int = Query(default=0, ge=0),
+    limit: int = Query(default=9, ge=1)
+    ):
+    queryset = select(models.Book)
+
+    if author_id is not None:
+        queryset = queryset.join(models.Author).where(models.Author.id == author_id)
+
+    return db.scalars(queryset).offset(skip).limit(limit).all()
+
+
+def get_book(db: Session, book_id: int):
+    return db.scalar(select(models.Book).where(models.Book.id == book_id))
+
+
+def create_book(db: Session, book: BookCreate):
+    db_book = models.Book(
+        title=book.title,
+        summary=book.summary,
+        publication_date=book.publication_date,
+        author_id=book.author_id,
+    )
+    db.add(db_book)
+    db.commit()
+    db.refresh(db_book)
+
+    return db_book

database.py

@@ -0,0 +1,16 @@
+from sqlalchemy import create_engine
+from sqlalchemy.ext.declarative import declarative_base
+from sqlalchemy.orm import sessionmaker
+
+
+SQLALCHEMY_DATABASE_URL = "sqlite:///./library.db"
+
+engine = create_engine(
+    SQLALCHEMY_DATABASE_URL, echo=True,
+)
+
+SessionLocal = sessionmaker(autocommit=True,
+                            autoflush=False,
+                            bind=engine)
+
+base = declarative_base()

main.py

@@ -0,0 +1,69 @@
+from sqlalchemy.orm import Session
+
+from fastapi import FastAPI, Depends, HTTPException
+
+import crud
+import schemas
+from database import base, engine, SessionLocal
+
+app = FastAPI()
+
+
+base.metadata.create_all(bind=engine)
+
+
+def get_db() -> Session:
+    db = SessionLocal()
+    try:
+        yield db
+    finally:
+        db.close()
+
+
+@app.get("/authors/", response_model=list[schemas.AuthorList])
+def authors_list(db: Session = Depends(get_db)):
+    return crud.get_all_authors(db)
+
+
+@app.get("/authors/{author_id}/", response_model=schemas.AuthorList)
+def author_detail(
+    author_id: int,
+    db: Session = Depends(get_db)
+    ):
+    author = crud.get_author(db=db, author_id=author_id)
+
+    if author is None:
+        raise HTTPException(status_code=404, detail="Author with this id is not found")
+
+    return author
+
+
+@app.post("/authors/", response_model=schemas.AuthorList)
+def author_create(
+    author: schemas.AuthorCreate,
+    db: Session = Depends(get_db)
+):
+    return crud.create_author(db=db, author=author)
+
+
+@app.get("/books/", response_model=list[schemas.BookList])
+def get_all_books(
+        author_id: int | None = None,
+        db: Session = Depends(get_db)
+    ):
+    return crud.get_all_books(db=db, author_id=author_id)
+
+
+@app.get("/books/{book_id}/", response_model=schemas.BookList)
+def book_detail(book_id: int, db: Session = Depends(get_db)):
+    book = crud.get_book(db=db, book_id=book_id)
+
+    if book is None:
+        raise HTTPException(status_code=404, detail="Book with this id is not found")
+
+    return book
+
+
+@app.post("/books/", response_model=schemas.BookList)
+def create_book(book: schemas.BookCreate, db: Session = Depends(get_db)):
+    return crud.create_book(db=db, book=book)

models.py

@@ -0,0 +1,29 @@
+from datetime import date
+
+from sqlalchemy import String, ForeignKey, Date
+
+from database import base
+from sqlalchemy.orm import Mapped, mapped_column, relationship
+
+
+class Author(base):
+    __tablename__ = "author"
+
+    id: Mapped[int] = mapped_column(primary_key=True)
+    name: Mapped[str] = mapped_column(String(255), unique=True)
+    bio: Mapped[str] = mapped_column(String(511))
+
+    books: Mapped[list["Book"]] = relationship(back_populates="author")
+
+
+class Book(base):
+    __tablename__ = "book"
+
+    id: Mapped[int] = mapped_column(primary_key=True)
+    title: Mapped[str] = mapped_column(String(255))
+    summary: Mapped[str] = mapped_column(String(255))
+    publication_date: Mapped[date] = mapped_column(Date)
+    author_id: Mapped[int] = mapped_column(ForeignKey("author.id"))
+
+    author: Mapped["Author"] = relationship(back_populates="books")
+

schemas.py

@@ -0,0 +1,35 @@
+from pydantic import BaseModel, ConfigDict
+
+from datetime import date
+
+
+class AuthorBase(BaseModel):
+    name: str
+    bio: str
+
+
+class AuthorCreate(AuthorBase):
+    pass
+
+
+class AuthorList(AuthorBase):
+    id: int
+
+    model_config = ConfigDict(from_attributes=True)
+
+
+class BookBase(BaseModel):
+    title: str
+    summary: str
+    publication_date: date
+
+
+class BookCreate(BookBase):
+    author_id: int
+
+
+class BookList(BookBase):
+    id: int
+    author: AuthorList
+
+    model_config = ConfigDict(from_attributes=True)