Implement Task Manager API with FastAPI and SQLite

README.md

@@ -1,3 +1,110 @@
-# FastAPI Application
+# Task Manager API
 
-This is a FastAPI application bootstrapped by BackendIM, the AI-powered backend generation platform.
+A RESTful API for managing tasks and to-do items, built with FastAPI and SQLite.
+
+## Features
+
+- Create, read, update, and delete tasks
+- Filter tasks by status, priority, and completion status
+- Pagination support for listing tasks
+- Data validation with Pydantic models
+- Database migrations with Alembic
+- Comprehensive error handling
+- API documentation with Swagger UI and ReDoc
+
+## Project Structure
+
+```
+taskmanagerapi/
+├── alembic.ini                 # Alembic configuration
+├── app/                        # Main application package
+│   ├── api/                    # API endpoints
+│   │   ├── v1/                 # API version 1
+│   │   │   ├── endpoints/      # API endpoint modules
+│   │   │   │   ├── health.py   # Health check endpoint
+│   │   │   │   └── tasks.py    # Task CRUD endpoints
+│   │   │   └── router.py       # API router
+│   ├── core/                   # Core application modules
+│   │   ├── config.py           # Application configuration
+│   │   ├── error_handlers.py   # Error handling middleware
+│   │   └── exceptions.py       # Custom exceptions
+│   ├── db/                     # Database modules
+│   │   └── session.py          # Database session
+│   ├── models/                 # SQLAlchemy models
+│   │   └── task.py             # Task model
+│   ├── schemas/                # Pydantic schemas
+│   │   ├── responses.py        # Response schemas
+│   │   └── task.py             # Task schemas
+│   ├── services/               # Business logic
+│   │   └── task.py             # Task service
+│   └── storage/                # Storage directory
+│       └── db/                 # Database directory
+├── migrations/                 # Alembic migrations
+│   ├── versions/               # Migration versions
+│   │   └── 0001_create_tasks_table.py
+│   ├── env.py                  # Alembic environment
+│   └── script.py.mako          # Alembic script template
+├── main.py                     # Application entry point
+├── pyproject.toml              # Project configuration
+└── requirements.txt            # Project dependencies
+```
+
+## API Endpoints
+
+- **GET /api/v1/health** - Health check endpoint
+- **GET /api/v1/tasks** - List tasks with optional filtering and pagination
+- **POST /api/v1/tasks** - Create a new task
+- **GET /api/v1/tasks/{task_id}** - Get a specific task
+- **PUT /api/v1/tasks/{task_id}** - Update a specific task
+- **DELETE /api/v1/tasks/{task_id}** - Delete a specific task
+
+## Task Model
+
+- **id**: Integer - Task ID
+- **title**: String - Task title
+- **description**: String (optional) - Task description
+- **status**: Enum - Task status (todo, in_progress, done)
+- **priority**: Enum - Task priority (low, medium, high)
+- **due_date**: DateTime (optional) - Task due date
+- **completed**: Boolean - Whether the task is completed
+- **created_at**: DateTime - Task creation timestamp
+- **updated_at**: DateTime - Task update timestamp
+
+## Requirements
+
+- Python 3.8+
+- FastAPI
+- SQLAlchemy
+- Alembic
+- Pydantic
+- Uvicorn
+
+## Getting Started
+
+1. Clone the repository
+2. Install dependencies:
+   ```bash
+   pip install -r requirements.txt
+   ```
+3. Run database migrations:
+   ```bash
+   alembic upgrade head
+   ```
+4. Start the application:
+   ```bash
+   uvicorn main:app --reload
+   ```
+5. Access the API documentation:
+   - Swagger UI: http://localhost:8000/docs
+   - ReDoc: http://localhost:8000/redoc
+
+## Development
+
+- Linting:
+  ```bash
+  ruff check .
+  ```
+- Auto-fix linting issues:
+  ```bash
+  ruff check --fix .
+  ```

alembic.ini

@@ -0,0 +1,106 @@
+# A generic, single database configuration.
+
+[alembic]
+# path to migration scripts
+script_location = migrations
+
+# template used to generate migration file names; The default value is %%(rev)s_%%(slug)s
+# Uncomment the line below if you want the files to be prepended with date and time
+# see https://alembic.sqlalchemy.org/en/latest/tutorial.html#editing-the-ini-file
+# for all available tokens
+# file_template = %%(year)d_%%(month).2d_%%(day).2d_%%(hour).2d%%(minute).2d-%%(rev)s_%%(slug)s
+
+# sys.path path, will be prepended to sys.path if present.
+# defaults to the current working directory.
+prepend_sys_path = .
+
+# timezone to use when rendering the date within the migration file
+# as well as the filename.
+# If specified, requires the python-dateutil library that can be
+# installed by adding `alembic[tz]` to the pip requirements
+# string value is passed to dateutil.tz.gettz()
+# leave blank for localtime
+# timezone =
+
+# max length of characters to apply to the
+# "slug" field
+# truncate_slug_length = 40
+
+# set to 'true' to run the environment during
+# the 'revision' command, regardless of autogenerate
+# revision_environment = false
+
+# set to 'true' to allow .pyc and .pyo files without
+# a source .py file to be detected as revisions in the
+# versions/ directory
+# sourceless = false
+
+# version location specification; This defaults
+# to migrations/versions.  When using multiple version
+# directories, initial revisions must be specified with --version-path.
+# The path separator used here should be the separator specified by "version_path_separator" below.
+# version_locations = %(here)s/bar:%(here)s/bat:migrations/versions
+
+# version path separator; As mentioned above, this is the character used to split
+# version_locations. The default within new alembic.ini files is "os", which uses os.pathsep.
+# If this key is omitted entirely, it falls back to the legacy behavior of splitting on spaces and/or commas.
+# Valid values for version_path_separator are:
+#
+# version_path_separator = :
+# version_path_separator = ;
+# version_path_separator = space
+version_path_separator = os  # Use os.pathsep. Default configuration used for new projects.
+
+# the output encoding used when revision files
+# are written from script.py.mako
+# output_encoding = utf-8
+
+# SQLite URL
+sqlalchemy.url = sqlite:////app/storage/db/db.sqlite
+
+
+[post_write_hooks]
+# post_write_hooks defines scripts or Python functions that are run
+# on newly generated revision scripts.  See the documentation for further
+# detail and examples
+
+# format using "black" - use the console_scripts runner, against the "black" entrypoint
+# hooks = black
+# black.type = console_scripts
+# black.entrypoint = black
+# black.options = -l 79 REVISION_SCRIPT_FILENAME
+
+# Logging configuration
+[loggers]
+keys = root,sqlalchemy,alembic
+
+[handlers]
+keys = console
+
+[formatters]
+keys = generic
+
+[logger_root]
+level = WARN
+handlers = console
+qualname =
+
+[logger_sqlalchemy]
+level = WARN
+handlers =
+qualname = sqlalchemy.engine
+
+[logger_alembic]
+level = INFO
+handlers =
+qualname = alembic
+
+[handler_console]
+class = StreamHandler
+args = (sys.stderr,)
+level = NOTSET
+formatter = generic
+
+[formatter_generic]
+format = %(levelname)-5.5s [%(name)s] %(message)s
+datefmt = %H:%M:%S

app/api/v1/endpoints/health.py

@@ -0,0 +1,15 @@
+from fastapi import APIRouter
+
+from app.schemas.responses import HealthCheck
+
+router = APIRouter()
+
+
+@router.get("/", response_model=HealthCheck)
+def health_check():
+    """Health check endpoint.
+    
+    Returns:
+        Health check response
+    """
+    return HealthCheck()

app/api/v1/endpoints/tasks.py

@@ -0,0 +1,73 @@
+from typing import Optional
+
+from fastapi import APIRouter, Depends, Path, Query, status
+from sqlalchemy.orm import Session
+
+from app.db.session import get_db
+from app.models.task import TaskPriority, TaskStatus
+from app.schemas.responses import PaginatedResponse
+from app.schemas.task import Task, TaskCreate, TaskUpdate
+from app.services.task import TaskService
+
+router = APIRouter()
+
+
+@router.get("/", response_model=PaginatedResponse[Task])
+def get_tasks(
+    skip: int = Query(0, ge=0, description="Number of tasks to skip"),
+    limit: int = Query(100, gt=0, le=1000, description="Maximum number of tasks to return"),
+    status: Optional[TaskStatus] = Query(None, description="Filter by task status"),
+    priority: Optional[TaskPriority] = Query(None, description="Filter by task priority"),
+    completed: Optional[bool] = Query(None, description="Filter by completion status"),
+    db: Session = Depends(get_db),
+):
+    """Get a list of tasks with optional filtering and pagination.
+    """
+    tasks = TaskService.get_tasks(
+        db, skip=skip, limit=limit, status=status, priority=priority, completed=completed
+    )
+    
+    total = TaskService.count_tasks(
+        db, status=status, priority=priority, completed=completed
+    )
+    
+    return PaginatedResponse.create(tasks, total, skip, limit)
+
+
+@router.post("/", response_model=Task, status_code=status.HTTP_201_CREATED)
+def create_task(task_data: TaskCreate, db: Session = Depends(get_db)):
+    """Create a new task.
+    """
+    return TaskService.create_task(db, task_data)
+
+
+@router.get("/{task_id}", response_model=Task)
+def get_task(
+    task_id: int = Path(..., gt=0, description="The ID of the task"),
+    db: Session = Depends(get_db),
+):
+    """Get a specific task by ID.
+    """
+    return TaskService.get_task(db, task_id)
+
+
+@router.put("/{task_id}", response_model=Task)
+def update_task(
+    task_data: TaskUpdate,
+    task_id: int = Path(..., gt=0, description="The ID of the task"),
+    db: Session = Depends(get_db),
+):
+    """Update a specific task by ID.
+    """
+    return TaskService.update_task(db, task_id, task_data)
+
+
+@router.delete("/{task_id}", status_code=status.HTTP_204_NO_CONTENT, response_model=None)
+def delete_task(
+    task_id: int = Path(..., gt=0, description="The ID of the task"),
+    db: Session = Depends(get_db),
+):
+    """Delete a specific task by ID.
+    """
+    TaskService.delete_task(db, task_id)
+    return None

app/api/v1/router.py

@@ -0,0 +1,9 @@
+from fastapi import APIRouter
+
+from app.api.v1.endpoints import health, tasks
+
+api_router = APIRouter()
+
+# Include routers for endpoints
+api_router.include_router(health.router, prefix="/health", tags=["health"])
+api_router.include_router(tasks.router, prefix="/tasks", tags=["tasks"])

app/core/config.py

@@ -0,0 +1,40 @@
+from pathlib import Path
+from typing import List, Optional
+
+from pydantic import field_validator
+from pydantic_settings import BaseSettings
+
+
+class Settings(BaseSettings):
+    """Application settings."""
+    
+    # API
+    API_V1_STR: str = "/api/v1"
+    
+    # Application
+    PROJECT_NAME: str = "Task Manager API"
+    PROJECT_DESCRIPTION: str = "API for managing tasks and to-do items"
+    VERSION: str = "0.1.0"
+    
+    # CORS
+    CORS_ORIGINS: List[str] = ["*"]
+    
+    # SQLite Database
+    DB_DIR: Path = Path("/app/storage/db")
+    DB_NAME: str = "db.sqlite"
+    SQLALCHEMY_DATABASE_URL: Optional[str] = None
+    
+    @field_validator("SQLALCHEMY_DATABASE_URL", mode="before")
+    def assemble_db_url(cls, v: Optional[str], info) -> str:
+        if v is not None:
+            return v
+        
+        db_dir = info.data.get("DB_DIR")
+        db_name = info.data.get("DB_NAME")
+        
+        db_dir.mkdir(parents=True, exist_ok=True)
+        
+        return f"sqlite:///{db_dir}/{db_name}"
+
+
+settings = Settings()

app/core/error_handlers.py

@@ -0,0 +1,110 @@
+from fastapi import FastAPI, Request
+from fastapi.exceptions import RequestValidationError
+from fastapi.responses import JSONResponse
+from pydantic import ValidationError
+from sqlalchemy.exc import SQLAlchemyError
+
+from app.core.exceptions import TaskManagerException
+from app.schemas.responses import ErrorResponse
+
+
+def add_error_handlers(app: FastAPI) -> None:
+    """Add error handlers to the FastAPI application.
+    
+    Args:
+        app: FastAPI application
+    """
+    
+    @app.exception_handler(TaskManagerException)
+    async def task_manager_exception_handler(
+        request: Request, exc: TaskManagerException
+    ) -> JSONResponse:
+        """Handle TaskManagerException.
+        
+        Args:
+            request: FastAPI request
+            exc: TaskManagerException
+            
+        Returns:
+            JSONResponse with error details
+        """
+        return JSONResponse(
+            status_code=exc.status_code,
+            content=ErrorResponse(detail=exc.detail).model_dump(),
+        )
+    
+    @app.exception_handler(RequestValidationError)
+    async def validation_exception_handler(
+        request: Request, exc: RequestValidationError
+    ) -> JSONResponse:
+        """Handle RequestValidationError.
+        
+        Args:
+            request: FastAPI request
+            exc: RequestValidationError
+            
+        Returns:
+            JSONResponse with error details
+        """
+        return JSONResponse(
+            status_code=422,
+            content=ErrorResponse(detail=str(exc)).model_dump(),
+        )
+    
+    @app.exception_handler(ValidationError)
+    async def pydantic_validation_exception_handler(
+        request: Request, exc: ValidationError
+    ) -> JSONResponse:
+        """Handle Pydantic ValidationError.
+        
+        Args:
+            request: FastAPI request
+            exc: ValidationError
+            
+        Returns:
+            JSONResponse with error details
+        """
+        return JSONResponse(
+            status_code=422,
+            content=ErrorResponse(detail=str(exc)).model_dump(),
+        )
+    
+    @app.exception_handler(SQLAlchemyError)
+    async def sqlalchemy_exception_handler(
+        request: Request, exc: SQLAlchemyError
+    ) -> JSONResponse:
+        """Handle SQLAlchemy errors.
+        
+        Args:
+            request: FastAPI request
+            exc: SQLAlchemyError
+            
+        Returns:
+            JSONResponse with error details
+        """
+        return JSONResponse(
+            status_code=500,
+            content=ErrorResponse(
+                detail="Database error occurred. Please try again later."
+            ).model_dump(),
+        )
+    
+    @app.exception_handler(Exception)
+    async def general_exception_handler(
+        request: Request, exc: Exception
+    ) -> JSONResponse:
+        """Handle general exceptions.
+        
+        Args:
+            request: FastAPI request
+            exc: Exception
+            
+        Returns:
+            JSONResponse with error details
+        """
+        return JSONResponse(
+            status_code=500,
+            content=ErrorResponse(
+                detail="An unexpected error occurred. Please try again later."
+            ).model_dump(),
+        )

app/core/exceptions.py

@@ -0,0 +1,54 @@
+from typing import Any, Dict, Optional
+
+from fastapi import HTTPException, status
+
+
+class TaskManagerException(HTTPException):
+    """Base exception for the Task Manager API."""
+    
+    def __init__(
+        self,
+        status_code: int,
+        detail: Any = None,
+        headers: Optional[Dict[str, Any]] = None,
+    ) -> None:
+        super().__init__(status_code=status_code, detail=detail, headers=headers)
+
+
+class TaskNotFoundException(TaskManagerException):
+    """Exception raised when a task is not found."""
+    
+    def __init__(
+        self,
+        detail: Any = "Task not found",
+        headers: Optional[Dict[str, Any]] = None,
+    ) -> None:
+        super().__init__(
+            status_code=status.HTTP_404_NOT_FOUND, detail=detail, headers=headers
+        )
+
+
+class ValidationException(TaskManagerException):
+    """Exception raised when validation fails."""
+    
+    def __init__(
+        self,
+        detail: Any = "Validation error",
+        headers: Optional[Dict[str, Any]] = None,
+    ) -> None:
+        super().__init__(
+            status_code=status.HTTP_422_UNPROCESSABLE_ENTITY, detail=detail, headers=headers
+        )
+
+
+class DatabaseException(TaskManagerException):
+    """Exception raised when a database operation fails."""
+    
+    def __init__(
+        self,
+        detail: Any = "Database operation failed",
+        headers: Optional[Dict[str, Any]] = None,
+    ) -> None:
+        super().__init__(
+            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR, detail=detail, headers=headers
+        )

app/db/session.py

@@ -0,0 +1,30 @@
+from sqlalchemy import create_engine
+from sqlalchemy.ext.declarative import declarative_base
+from sqlalchemy.orm import sessionmaker
+
+from app.core.config import settings
+
+# Create SQLAlchemy engine
+engine = create_engine(
+    settings.SQLALCHEMY_DATABASE_URL,
+    connect_args={"check_same_thread": False}
+)
+
+# Create SessionLocal class
+SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
+
+# Create Base class for models
+Base = declarative_base()
+
+# Dependency for getting DB session
+def get_db():
+    """Dependency function that yields DB sessions.
+    
+    Yields:
+        db: SQLAlchemy database session
+    """
+    db = SessionLocal()
+    try:
+        yield db
+    finally:
+        db.close()

app/models/__init__.py

@@ -0,0 +1,3 @@
+from app.models.task import Task, TaskPriority, TaskStatus
+
+__all__ = ["Task", "TaskStatus", "TaskPriority"]

app/models/task.py

@@ -0,0 +1,56 @@
+from enum import Enum as PyEnum
+
+from sqlalchemy import Boolean, Column, DateTime, Enum, Integer, String, Text
+from sqlalchemy.sql import func
+
+from app.db.session import Base
+
+
+class TaskStatus(str, PyEnum):
+    """Enum for task status."""
+    
+    TODO = "todo"
+    IN_PROGRESS = "in_progress"
+    DONE = "done"
+
+
+class TaskPriority(str, PyEnum):
+    """Enum for task priority."""
+    
+    LOW = "low"
+    MEDIUM = "medium"
+    HIGH = "high"
+
+
+class Task(Base):
+    """SQLAlchemy model for tasks."""
+    
+    __tablename__ = "tasks"
+    
+    id = Column(Integer, primary_key=True, index=True)
+    title = Column(String(255), nullable=False, index=True)
+    description = Column(Text, nullable=True)
+    status = Column(
+        Enum(TaskStatus),
+        default=TaskStatus.TODO,
+        nullable=False,
+        index=True
+    )
+    priority = Column(
+        Enum(TaskPriority),
+        default=TaskPriority.MEDIUM,
+        nullable=False,
+        index=True
+    )
+    due_date = Column(DateTime, nullable=True)
+    completed = Column(Boolean, default=False, nullable=False, index=True)
+    created_at = Column(DateTime, default=func.now(), nullable=False)
+    updated_at = Column(
+        DateTime,
+        default=func.now(),
+        onupdate=func.now(),
+        nullable=False
+    )
+    
+    def __repr__(self) -> str:
+        return f"Task(id={self.id}, title={self.title}, status={self.status})"

app/schemas/__init__.py

@@ -0,0 +1,19 @@
+from app.schemas.responses import (
+    ErrorResponse,
+    HealthCheck,
+    PaginatedResponse,
+    PaginationParams,
+)
+from app.schemas.task import Task, TaskBase, TaskCreate, TaskInDB, TaskUpdate
+
+__all__ = [
+    "TaskBase",
+    "TaskCreate",
+    "TaskUpdate",
+    "TaskInDB",
+    "Task",
+    "HealthCheck",
+    "ErrorResponse",
+    "PaginationParams",
+    "PaginatedResponse",
+]

app/schemas/responses.py

@@ -0,0 +1,49 @@
+from typing import Generic, List, TypeVar
+
+from pydantic import BaseModel, Field
+
+T = TypeVar("T")
+
+
+class HealthCheck(BaseModel):
+    """Health check response schema."""
+    
+    status: str = "ok"
+    message: str = "Application is healthy"
+
+
+class ErrorResponse(BaseModel):
+    """Error response schema."""
+    
+    detail: str
+
+
+class PaginationParams(BaseModel):
+    """Pagination parameters schema."""
+    
+    skip: int = Field(0, ge=0, description="Number of items to skip")
+    limit: int = Field(100, gt=0, le=1000, description="Maximum number of items to return")
+
+
+class PaginatedResponse(BaseModel, Generic[T]):
+    """Paginated response schema."""
+    
+    items: List[T]
+    total: int
+    page: int
+    pages: int
+    
+    @classmethod
+    def create(
+        cls, items: List[T], total: int, skip: int = 0, limit: int = 100
+    ) -> "PaginatedResponse[T]":
+        """Create a paginated response."""
+        page = skip // limit + 1 if limit > 0 else 1
+        pages = (total + limit - 1) // limit if limit > 0 else 1
+        
+        return cls(
+            items=items,
+            total=total,
+            page=page,
+            pages=pages,
+        )

app/schemas/task.py

@@ -0,0 +1,52 @@
+from datetime import datetime
+from typing import Optional
+
+from pydantic import BaseModel, Field
+
+from app.models.task import TaskPriority, TaskStatus
+
+
+class TaskBase(BaseModel):
+    """Base model for task schema."""
+    
+    title: str = Field(..., min_length=1, max_length=255, description="Task title")
+    description: Optional[str] = Field(None, description="Task description")
+    status: TaskStatus = Field(default=TaskStatus.TODO, description="Task status")
+    priority: TaskPriority = Field(default=TaskPriority.MEDIUM, description="Task priority")
+    due_date: Optional[datetime] = Field(None, description="Due date")
+    completed: bool = Field(default=False, description="Whether the task is completed")
+
+
+class TaskCreate(TaskBase):
+    """Schema for creating a new task."""
+    pass
+
+
+class TaskUpdate(BaseModel):
+    """Schema for updating an existing task."""
+    
+    title: Optional[str] = Field(None, min_length=1, max_length=255, description="Task title")
+    description: Optional[str] = Field(None, description="Task description")
+    status: Optional[TaskStatus] = Field(None, description="Task status")
+    priority: Optional[TaskPriority] = Field(None, description="Task priority")
+    due_date: Optional[datetime] = Field(None, description="Due date")
+    completed: Optional[bool] = Field(None, description="Whether the task is completed")
+
+
+class TaskInDB(TaskBase):
+    """Schema for task in database."""
+    
+    id: int
+    created_at: datetime
+    updated_at: datetime
+    
+    class Config:
+        """Configuration for the model."""
+        
+        orm_mode = True
+        from_attributes = True
+
+
+class Task(TaskInDB):
+    """Schema for task response."""
+    pass

app/services/__init__.py

@@ -0,0 +1,3 @@
+from app.services.task import TaskService
+
+__all__ = ["TaskService"]

app/services/task.py

@@ -0,0 +1,173 @@
+from datetime import datetime
+from typing import List, Optional
+
+from sqlalchemy import select
+from sqlalchemy.orm import Session
+from sqlalchemy.sql import func
+
+from app.core.exceptions import TaskNotFoundException
+from app.models.task import Task, TaskPriority, TaskStatus
+from app.schemas.task import TaskCreate, TaskUpdate
+
+
+class TaskService:
+    """Service for task operations."""
+    
+    @staticmethod
+    def get_tasks(
+        db: Session,
+        skip: int = 0,
+        limit: int = 100,
+        status: Optional[TaskStatus] = None,
+        priority: Optional[TaskPriority] = None,
+        completed: Optional[bool] = None,
+    ) -> List[Task]:
+        """Get a list of tasks with optional filtering.
+        
+        Args:
+            db: Database session
+            skip: Number of items to skip
+            limit: Maximum number of items to return
+            status: Filter by task status
+            priority: Filter by task priority
+            completed: Filter by completion status
+            
+        Returns:
+            List of tasks
+        """
+        query = select(Task)
+        
+        if status is not None:
+            query = query.where(Task.status == status)
+        
+        if priority is not None:
+            query = query.where(Task.priority == priority)
+        
+        if completed is not None:
+            query = query.where(Task.completed == completed)
+        
+        query = query.offset(skip).limit(limit)
+        
+        return db.execute(query).scalars().all()
+    
+    @staticmethod
+    def count_tasks(
+        db: Session,
+        status: Optional[TaskStatus] = None,
+        priority: Optional[TaskPriority] = None,
+        completed: Optional[bool] = None,
+    ) -> int:
+        """Count tasks with optional filtering.
+        
+        Args:
+            db: Database session
+            status: Filter by task status
+            priority: Filter by task priority
+            completed: Filter by completion status
+            
+        Returns:
+            Number of tasks
+        """
+        query = select(func.count(Task.id))
+        
+        if status is not None:
+            query = query.where(Task.status == status)
+        
+        if priority is not None:
+            query = query.where(Task.priority == priority)
+        
+        if completed is not None:
+            query = query.where(Task.completed == completed)
+        
+        return db.execute(query).scalar_one()
+    
+    @staticmethod
+    def get_task(db: Session, task_id: int) -> Task:
+        """Get a task by ID.
+        
+        Args:
+            db: Database session
+            task_id: ID of the task
+            
+        Returns:
+            Task
+            
+        Raises:
+            HTTPException: If task is not found
+        """
+        task = db.get(Task, task_id)
+        
+        if task is None:
+            raise TaskNotFoundException(detail=f"Task with id {task_id} not found")
+        
+        return task
+    
+    @staticmethod
+    def create_task(db: Session, task_data: TaskCreate) -> Task:
+        """Create a new task.
+        
+        Args:
+            db: Database session
+            task_data: Task data
+            
+        Returns:
+            Created task
+        """
+        task = Task(**task_data.model_dump())
+        
+        db.add(task)
+        db.commit()
+        db.refresh(task)
+        
+        return task
+    
+    @staticmethod
+    def update_task(db: Session, task_id: int, task_data: TaskUpdate) -> Task:
+        """Update an existing task.
+        
+        Args:
+            db: Database session
+            task_id: ID of the task
+            task_data: Updated task data
+            
+        Returns:
+            Updated task
+            
+        Raises:
+            HTTPException: If task is not found
+        """
+        task = TaskService.get_task(db, task_id)
+        
+        data = task_data.model_dump(exclude_unset=True)
+        
+        for key, value in data.items():
+            setattr(task, key, value)
+        
+        # Update the updated_at field
+        task.updated_at = datetime.now()
+        
+        # If status is changed to DONE, mark as completed
+        if task_data.status == TaskStatus.DONE:
+            task.completed = True
+        
+        db.add(task)
+        db.commit()
+        db.refresh(task)
+        
+        return task
+    
+    @staticmethod
+    def delete_task(db: Session, task_id: int) -> None:
+        """Delete a task.
+        
+        Args:
+            db: Database session
+            task_id: ID of the task
+            
+        Raises:
+            HTTPException: If task is not found
+        """
+        task = TaskService.get_task(db, task_id)
+        
+        db.delete(task)
+        db.commit()

main.py

@@ -0,0 +1,41 @@
+import uvicorn
+from fastapi import FastAPI
+from fastapi.middleware.cors import CORSMiddleware
+
+from app.api.v1.router import api_router
+from app.core.config import settings
+from app.core.error_handlers import add_error_handlers
+
+app = FastAPI(
+    title=settings.PROJECT_NAME,
+    description=settings.PROJECT_DESCRIPTION,
+    version=settings.VERSION,
+    openapi_url=f"{settings.API_V1_STR}/openapi.json",
+    docs_url="/docs",
+    redoc_url="/redoc",
+)
+
+# Set up CORS middleware
+app.add_middleware(
+    CORSMiddleware,
+    allow_origins=settings.CORS_ORIGINS,
+    allow_credentials=True,
+    allow_methods=["*"],
+    allow_headers=["*"],
+)
+
+# Add error handlers
+add_error_handlers(app)
+
+# Include API router
+app.include_router(api_router, prefix=settings.API_V1_STR)
+
+# Root path redirect to docs
+@app.get("/", include_in_schema=False)
+async def root_redirect():
+    """Redirect root path to API documentation."""
+    from fastapi.responses import RedirectResponse
+    return RedirectResponse(url="/docs")
+
+if __name__ == "__main__":
+    uvicorn.run("main:app", host="0.0.0.0", port=8000, reload=True)

migrations/env.py

@@ -0,0 +1,83 @@
+from logging.config import fileConfig
+
+from sqlalchemy import engine_from_config
+from sqlalchemy import pool
+
+from alembic import context
+
+# Import database models to be included in migrations
+from app.db.session import Base
+from app.models import Task
+
+# this is the Alembic Config object, which provides
+# access to the values within the .ini file in use.
+config = context.config
+
+# Interpret the config file for Python logging.
+# This line sets up loggers basically.
+if config.config_file_name is not None:
+    fileConfig(config.config_file_name)
+
+# add your model's MetaData object here
+# for 'autogenerate' support
+target_metadata = Base.metadata
+
+# other values from the config, defined by the needs of env.py,
+# can be acquired:
+# my_important_option = config.get_main_option("my_important_option")
+# ... etc.
+
+
+def run_migrations_offline() -> None:
+    """Run migrations in 'offline' mode.
+
+    This configures the context with just a URL
+    and not an Engine, though an Engine is acceptable
+    here as well.  By skipping the Engine creation
+    we don't even need a DBAPI to be available.
+
+    Calls to context.execute() here emit the given string to the
+    script output.
+
+    """
+    url = config.get_main_option("sqlalchemy.url")
+    context.configure(
+        url=url,
+        target_metadata=target_metadata,
+        literal_binds=True,
+        dialect_opts={"paramstyle": "named"},
+    )
+
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+def run_migrations_online() -> None:
+    """Run migrations in 'online' mode.
+
+    In this scenario we need to create an Engine
+    and associate a connection with the context.
+
+    """
+    connectable = engine_from_config(
+        config.get_section(config.config_ini_section, {}),
+        prefix="sqlalchemy.",
+        poolclass=pool.NullPool,
+    )
+
+    with connectable.connect() as connection:
+        is_sqlite = connection.dialect.name == 'sqlite'
+        context.configure(
+            connection=connection,
+            target_metadata=target_metadata,
+            render_as_batch=is_sqlite,  # Enable batch mode for SQLite
+        )
+
+        with context.begin_transaction():
+            context.run_migrations()
+
+
+if context.is_offline_mode():
+    run_migrations_offline()
+else:
+    run_migrations_online()

migrations/script.py.mako

@@ -0,0 +1,24 @@
+"""${message}
+
+Revision ID: ${up_revision}
+Revises: ${down_revision | comma,n}
+Create Date: ${create_date}
+
+"""
+from alembic import op
+import sqlalchemy as sa
+${imports if imports else ""}
+
+# revision identifiers, used by Alembic.
+revision = ${repr(up_revision)}
+down_revision = ${repr(down_revision)}
+branch_labels = ${repr(branch_labels)}
+depends_on = ${repr(depends_on)}
+
+
+def upgrade() -> None:
+    ${upgrades if upgrades else "pass"}
+
+
+def downgrade() -> None:
+    ${downgrades if downgrades else "pass"}

migrations/versions/0001_create_tasks_table.py

@@ -0,0 +1,41 @@
+"""create tasks table
+
+Revision ID: 0001
+Revises: 
+Create Date: 2023-08-01
+
+"""
+from alembic import op
+import sqlalchemy as sa
+from sqlalchemy.sql import func
+
+
+# revision identifiers, used by Alembic.
+revision = '0001'
+down_revision = None
+branch_labels = None
+depends_on = None
+
+
+def upgrade() -> None:
+    op.create_table(
+        'tasks',
+        sa.Column('id', sa.Integer(), nullable=False),
+        sa.Column('title', sa.String(255), nullable=False, index=True),
+        sa.Column('description', sa.Text(), nullable=True),
+        sa.Column('status', sa.Enum('todo', 'in_progress', 'done', name='taskstatus'), 
+                 nullable=False, default='todo', index=True),
+        sa.Column('priority', sa.Enum('low', 'medium', 'high', name='taskpriority'), 
+                 nullable=False, default='medium', index=True),
+        sa.Column('due_date', sa.DateTime(), nullable=True),
+        sa.Column('completed', sa.Boolean(), nullable=False, default=False, index=True),
+        sa.Column('created_at', sa.DateTime(), nullable=False, default=func.now()),
+        sa.Column('updated_at', sa.DateTime(), nullable=False, default=func.now(), onupdate=func.now()),
+        sa.PrimaryKeyConstraint('id'),
+    )
+    op.create_index('ix_tasks_id', 'tasks', ['id'])
+
+
+def downgrade() -> None:
+    op.drop_index('ix_tasks_id', 'tasks')
+    op.drop_table('tasks')

pyproject.toml

@@ -0,0 +1,41 @@
+[tool.ruff]
+line-length = 88
+target-version = "py38"
+
+[tool.ruff.lint]
+select = [
+    "E",    # pycodestyle errors
+    "F",    # pyflakes
+    "I",    # isort
+    "B",    # flake8-bugbear
+    "C4",   # flake8-comprehensions
+    "UP",   # pyupgrade
+    "D",    # pydocstyle
+    "N",    # pep8-naming
+]
+
+ignore = [
+    "D100",  # Missing docstring in public module
+    "D104",  # Missing docstring in public package
+    "D106",  # Missing docstring in public nested class
+    "D203",  # 1 blank line required before class docstring
+    "D213",  # Multi-line docstring summary should start at the second line
+    "E501",  # Line too long (covered by line-length)
+    "D200",  # One-line docstring should fit on one line
+    "D212",  # Multi-line docstring summary should start at the first line
+    "D107",  # Missing docstring in __init__
+    "D105",  # Missing docstring in magic method
+    "D102",  # Missing docstring in public method
+    "N805",  # First argument of a method should be named `self`
+    "B008",  # Do not perform function call in argument defaults
+]
+
+[tool.ruff.lint.per-file-ignores]
+"migrations/*" = ["D", "E", "F", "I", "N"]
+"__init__.py" = ["D", "F401"]
+
+[tool.ruff.lint.isort]
+known-first-party = ["app"]
+
+[tool.ruff.lint.pydocstyle]
+convention = "google"

requirements.txt

@@ -0,0 +1,9 @@
+fastapi>=0.103.1,<0.104.0
+uvicorn>=0.23.2,<0.24.0
+sqlalchemy>=2.0.20,<2.1.0
+alembic>=1.12.0,<1.13.0
+pydantic>=2.3.0,<2.4.0
+pydantic-settings>=2.0.3,<2.1.0
+python-multipart>=0.0.6,<0.1.0
+email-validator>=2.0.0,<2.1.0
+ruff>=0.0.292,<0.1.0