Add priority levels, enhanced pagination, and search/filtering

- Add Priority enum (low, medium, high) to Todo model with default medium
- Create migration to add priority field to existing todos table
- Enhance pagination with proper metadata (page, total, has_next, has_prev)
- Add search functionality across title and description fields
- Add filtering by completion status and priority level
- Update API endpoints with query parameters for filtering and search
- Add TodoListResponse schema for structured pagination response
- Format code with Ruff

alembic/versions/002_add_priority_field.py

@@ -0,0 +1,37 @@
+"""Add priority field to todos
+
+Revision ID: 002
+Revises: 001
+Create Date: 2024-01-01 00:00:00.000000
+
+"""
+
+from alembic import op
+import sqlalchemy as sa
+
+# revision identifiers, used by Alembic.
+revision = "002"
+down_revision = "001"
+branch_labels = None
+depends_on = None
+
+
+def upgrade() -> None:
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.add_column(
+        "todos",
+        sa.Column(
+            "priority",
+            sa.Enum("LOW", "MEDIUM", "HIGH", name="priority"),
+            nullable=True,
+        ),
+    )
+    # Set default value for existing records
+    op.execute("UPDATE todos SET priority = 'MEDIUM' WHERE priority IS NULL")
+    # ### end Alembic commands ###
+
+
+def downgrade() -> None:
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_column("todos", "priority")
+    # ### end Alembic commands ###

app/api/v1/todos.py

@@ -1,18 +1,45 @@
-from typing import List
-from fastapi import APIRouter, Depends, HTTPException
+from typing import Optional
+from fastapi import APIRouter, Depends, HTTPException, Query
 from sqlalchemy.orm import Session
+import math
 
 from app.crud import todo as todo_crud
 from app.db.session import get_db
-from app.schemas.todo import Todo, TodoCreate, TodoUpdate
+from app.models.todo import Priority
+from app.schemas.todo import Todo, TodoCreate, TodoUpdate, TodoListResponse
 
 router = APIRouter(prefix="/todos", tags=["todos"])
 
 
-@router.get("/", response_model=List[Todo])
-def read_todos(skip: int = 0, limit: int = 100, db: Session = Depends(get_db)):
-    todos = todo_crud.get_todos(db, skip=skip, limit=limit)
-    return todos
+@router.get("/", response_model=TodoListResponse)
+def read_todos(
+    page: int = Query(1, ge=1, description="Page number"),
+    per_page: int = Query(10, ge=1, le=100, description="Items per page"),
+    completed: Optional[bool] = Query(None, description="Filter by completion status"),
+    priority: Optional[Priority] = Query(None, description="Filter by priority"),
+    search: Optional[str] = Query(None, description="Search in title and description"),
+    db: Session = Depends(get_db),
+):
+    skip = (page - 1) * per_page
+    todos, total = todo_crud.get_todos(
+        db,
+        skip=skip,
+        limit=per_page,
+        completed=completed,
+        priority=priority,
+        search=search,
+    )
+
+    total_pages = math.ceil(total / per_page)
+
+    return TodoListResponse(
+        items=todos,
+        total=total,
+        page=page,
+        per_page=per_page,
+        has_next=page < total_pages,
+        has_prev=page > 1,
+    )
 
 
 @router.post("/", response_model=Todo)

app/crud/todo.py

@@ -1,7 +1,7 @@
-from typing import List, Optional
+from typing import List, Optional, Tuple
 from sqlalchemy.orm import Session
 
-from app.models.todo import Todo
+from app.models.todo import Todo, Priority
 from app.schemas.todo import TodoCreate, TodoUpdate
 
 
@@ -9,8 +9,33 @@ def get_todo(db: Session, todo_id: int) -> Optional[Todo]:
     return db.query(Todo).filter(Todo.id == todo_id).first()
 
 
-def get_todos(db: Session, skip: int = 0, limit: int = 100) -> List[Todo]:
-    return db.query(Todo).offset(skip).limit(limit).all()
+def get_todos(
+    db: Session,
+    skip: int = 0,
+    limit: int = 100,
+    completed: Optional[bool] = None,
+    priority: Optional[Priority] = None,
+    search: Optional[str] = None,
+) -> Tuple[List[Todo], int]:
+    query = db.query(Todo)
+
+    # Apply filters
+    if completed is not None:
+        query = query.filter(Todo.completed == completed)
+    if priority is not None:
+        query = query.filter(Todo.priority == priority)
+    if search:
+        query = query.filter(
+            Todo.title.contains(search) | Todo.description.contains(search)
+        )
+
+    # Get total count before pagination
+    total = query.count()
+
+    # Apply pagination and ordering
+    todos = query.order_by(Todo.created_at.desc()).offset(skip).limit(limit).all()
+
+    return todos, total
 
 
 def create_todo(db: Session, todo: TodoCreate) -> Todo:

app/models/todo.py

@@ -1,9 +1,16 @@
-from sqlalchemy import Column, Integer, String, Boolean, DateTime
+from sqlalchemy import Column, Integer, String, Boolean, DateTime, Enum
 from sqlalchemy.sql import func
+import enum
 
 from app.db.base import Base
 
 
+class Priority(str, enum.Enum):
+    LOW = "low"
+    MEDIUM = "medium"
+    HIGH = "high"
+
+
 class Todo(Base):
     __tablename__ = "todos"
 
@@ -11,5 +18,6 @@ class Todo(Base):
     title = Column(String(200), nullable=False)
     description = Column(String(500), nullable=True)
     completed = Column(Boolean, default=False)
+    priority = Column(Enum(Priority), default=Priority.MEDIUM)
     created_at = Column(DateTime(timezone=True), server_default=func.now())
     updated_at = Column(DateTime(timezone=True), onupdate=func.now())

app/schemas/__init__.py

@@ -1,3 +1,3 @@
-from .todo import Todo, TodoCreate, TodoUpdate
+from .todo import Todo, TodoCreate, TodoUpdate, TodoListResponse
 
-__all__ = ["Todo", "TodoCreate", "TodoUpdate"]
+__all__ = ["Todo", "TodoCreate", "TodoUpdate", "TodoListResponse"]

app/schemas/todo.py

@@ -2,11 +2,14 @@ from datetime import datetime
 from typing import Optional
 from pydantic import BaseModel
 
+from app.models.todo import Priority
+
 
 class TodoBase(BaseModel):
     title: str
     description: Optional[str] = None
     completed: bool = False
+    priority: Priority = Priority.MEDIUM
 
 
 class TodoCreate(TodoBase):
@@ -17,6 +20,7 @@ class TodoUpdate(BaseModel):
     title: Optional[str] = None
     description: Optional[str] = None
     completed: Optional[bool] = None
+    priority: Optional[Priority] = None
 
 
 class Todo(TodoBase):
@@ -26,3 +30,12 @@ class Todo(TodoBase):
 
     class Config:
         from_attributes = True
+
+
+class TodoListResponse(BaseModel):
+    items: list[Todo]
+    total: int
+    page: int
+    per_page: int
+    has_next: bool
+    has_prev: bool