Add Book schema

schemas/book.py

@@ -0,0 +1,42 @@
+from pydantic import BaseModel, Field
+
+# Base Schema
+class BookBase(BaseModel):
+    title: str = Field(..., description="Title of the book")
+    author: str = Field(..., description="Author of the book")
+    description: str = Field(..., description="Description of the book")
+    published_year: int = Field(..., gt=0, description="Year the book was published")
+
+# Schema for creating a new Book
+class BookCreate(BookBase):
+    isbn: str = Field(..., description="ISBN of the book")
+
+    class Config:
+        schema_extra = {
+            "example": {
+                "title": "The Great Gatsby",
+                "author": "F. Scott Fitzgerald",
+                "description": "A novel about the decadence of the Jazz Age.",
+                "published_year": 1925,
+                "isbn": "978-0743273565"
+            }
+        }
+
+# Schema for Book responses
+class Book(BookBase):
+    id: int
+    isbn: str
+
+    class Config:
+        orm_mode = True
+```
+
+This code defines three Pydantic schemas for the Book entity:
+
+1. `BookBase`: A base schema containing common fields for Book.
+2. `BookCreate`: A schema for creating a new Book, inheriting from `BookBase` and adding the `isbn` field.
+3. `Book`: A schema for Book responses, inheriting from `BookBase` and adding the `id` and `isbn` fields.
+
+The `Field` class is used to add validation and descriptions to the fields. For example, `published_year` is validated to be greater than 0, and `isbn` is required for creating a new Book.
+
+The `Config` class is used to provide examples for the `BookCreate` schema and to enable the `orm_mode` for the `Book` schema, which is useful when working with ORMs like SQLAlchemy.