Add complete Task Manager API with FastAPI and SQLite

- Created FastAPI application with CRUD operations for tasks
- Implemented SQLAlchemy models with Task entity
- Added Pydantic schemas for request/response validation
- Set up Alembic for database migrations
- Configured SQLite database with proper file structure
- Added health check and root endpoints
- Included comprehensive API documentation
- Applied CORS middleware for development
- Updated README with detailed setup and usage instructions
- Applied code formatting with ruff linter

README.md

@@ -1,3 +1,116 @@
-# FastAPI Application
+# Task Manager API
 
-This is a FastAPI application bootstrapped by BackendIM, the AI-powered backend generation platform.
+A simple and efficient Task Manager API built with FastAPI and SQLite. This API allows you to create, read, update, and delete tasks with full CRUD operations.
+
+## Features
+
+- Create new tasks with title and description
+- List all tasks with pagination support
+- Get individual task details
+- Update existing tasks (title, description, completion status)
+- Delete tasks
+- Mark tasks as completed/incomplete
+- Health check endpoint
+- Interactive API documentation
+
+## Technology Stack
+
+- **FastAPI** - Modern, fast web framework for building APIs
+- **SQLAlchemy** - SQL toolkit and Object-Relational Mapping (ORM)
+- **SQLite** - Lightweight, file-based database
+- **Alembic** - Database migration tool
+- **Pydantic** - Data validation using Python type annotations
+- **Uvicorn** - ASGI web server
+
+## Installation
+
+1. Install dependencies:
+```bash
+pip install -r requirements.txt
+```
+
+2. Run database migrations:
+```bash
+alembic upgrade head
+```
+
+3. Start the development server:
+```bash
+uvicorn main:app --reload
+```
+
+The API will be available at `http://localhost:8000`
+
+## API Documentation
+
+- **Interactive docs**: http://localhost:8000/docs
+- **ReDoc**: http://localhost:8000/redoc
+- **OpenAPI JSON**: http://localhost:8000/openapi.json
+
+## API Endpoints
+
+### Root
+- `GET /` - API information and links
+
+### Health Check
+- `GET /health` - Application health status
+
+### Tasks
+- `POST /api/tasks/` - Create a new task
+- `GET /api/tasks/` - Get all tasks (supports pagination with `skip` and `limit` parameters)
+- `GET /api/tasks/{task_id}` - Get a specific task by ID
+- `PUT /api/tasks/{task_id}` - Update a specific task
+- `DELETE /api/tasks/{task_id}` - Delete a specific task
+
+## Task Schema
+
+```json
+{
+  "id": 1,
+  "title": "Sample Task",
+  "description": "This is a sample task description",
+  "completed": false,
+  "created_at": "2024-01-01T12:00:00.000Z",
+  "updated_at": "2024-01-01T12:00:00.000Z"
+}
+```
+
+## Project Structure
+
+```
+├── main.py                 # FastAPI application entry point
+├── requirements.txt        # Python dependencies
+├── alembic.ini            # Alembic configuration
+├── alembic/               # Database migrations
+│   ├── versions/          # Migration files
+│   ├── env.py            # Alembic environment configuration
+│   └── script.py.mako    # Migration template
+├── app/
+│   ├── __init__.py
+│   ├── api/              # API route handlers
+│   │   ├── __init__.py
+│   │   └── tasks.py      # Task-related endpoints
+│   ├── db/               # Database configuration
+│   │   ├── __init__.py
+│   │   ├── base.py       # SQLAlchemy base
+│   │   └── session.py    # Database session management
+│   ├── models/           # SQLAlchemy models
+│   │   ├── __init__.py
+│   │   └── task.py       # Task model
+│   └── schemas/          # Pydantic schemas
+│       ├── __init__.py
+│       └── task.py       # Task schemas for validation
+└── storage/
+    └── db/               # SQLite database storage
+        └── db.sqlite     # Database file (created automatically)
+```
+
+## Development
+
+The application uses automatic CORS configuration to allow requests from any origin during development.
+
+Database migrations are handled through Alembic. The initial migration creates the tasks table with all necessary fields and indexes.
+
+## Environment Variables
+
+No environment variables are required for basic operation. The application uses SQLite with a local file-based database stored in `/app/storage/db/db.sqlite`.

alembic.ini

@@ -0,0 +1,42 @@
+[alembic]
+script_location = alembic
+prepend_sys_path = .
+version_path_separator = os
+
+sqlalchemy.url = sqlite:////app/storage/db/db.sqlite
+
+[post_write_hooks]
+
+[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

alembic/env.py

@@ -0,0 +1,50 @@
+from logging.config import fileConfig
+from sqlalchemy import engine_from_config
+from sqlalchemy import pool
+from alembic import context
+import sys
+import os
+
+sys.path.append(os.path.dirname(os.path.dirname(__file__)))
+
+from app.db.base import Base
+
+config = context.config
+
+if config.config_file_name is not None:
+    fileConfig(config.config_file_name)
+
+target_metadata = Base.metadata
+
+
+def run_migrations_offline() -> None:
+    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:
+    connectable = engine_from_config(
+        config.get_section(config.config_ini_section),
+        prefix="sqlalchemy.",
+        poolclass=pool.NullPool,
+    )
+
+    with connectable.connect() as connection:
+        context.configure(connection=connection, target_metadata=target_metadata)
+
+        with context.begin_transaction():
+            context.run_migrations()
+
+
+if context.is_offline_mode():
+    run_migrations_offline()
+else:
+    run_migrations_online()

alembic/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"}

alembic/versions/001_create_tasks_table.py

@@ -0,0 +1,37 @@
+"""create tasks table
+
+Revision ID: 001
+Revises:
+Create Date: 2024-01-01 12:00:00.000000
+
+"""
+
+from alembic import op
+import sqlalchemy as sa
+
+# revision identifiers, used by Alembic.
+revision = "001"
+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(), nullable=False),
+        sa.Column("description", sa.Text(), nullable=True),
+        sa.Column("completed", sa.Boolean(), nullable=False),
+        sa.Column("created_at", sa.DateTime(), nullable=False),
+        sa.Column("updated_at", sa.DateTime(), nullable=False),
+        sa.PrimaryKeyConstraint("id"),
+    )
+    op.create_index(op.f("ix_tasks_id"), "tasks", ["id"], unique=False)
+    op.create_index(op.f("ix_tasks_title"), "tasks", ["title"], unique=False)
+
+
+def downgrade() -> None:
+    op.drop_index(op.f("ix_tasks_title"), table_name="tasks")
+    op.drop_index(op.f("ix_tasks_id"), table_name="tasks")
+    op.drop_table("tasks")

app/api/__init__.py

@@ -0,0 +1,3 @@
+from .tasks import router as tasks_router
+
+__all__ = ["tasks_router"]

app/api/tasks.py

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+from typing import List
+from fastapi import APIRouter, Depends, HTTPException, status
+from sqlalchemy.orm import Session
+
+from app.db.session import get_db
+from app.models.task import Task
+from app.schemas.task import TaskCreate, TaskUpdate, TaskResponse
+
+router = APIRouter()
+
+
+@router.post("/", response_model=TaskResponse, status_code=status.HTTP_201_CREATED)
+def create_task(task: TaskCreate, db: Session = Depends(get_db)):
+    db_task = Task(**task.dict())
+    db.add(db_task)
+    db.commit()
+    db.refresh(db_task)
+    return db_task
+
+
+@router.get("/", response_model=List[TaskResponse])
+def read_tasks(skip: int = 0, limit: int = 100, db: Session = Depends(get_db)):
+    tasks = db.query(Task).offset(skip).limit(limit).all()
+    return tasks
+
+
+@router.get("/{task_id}", response_model=TaskResponse)
+def read_task(task_id: int, db: Session = Depends(get_db)):
+    task = db.query(Task).filter(Task.id == task_id).first()
+    if task is None:
+        raise HTTPException(status_code=404, detail="Task not found")
+    return task
+
+
+@router.put("/{task_id}", response_model=TaskResponse)
+def update_task(task_id: int, task_update: TaskUpdate, db: Session = Depends(get_db)):
+    task = db.query(Task).filter(Task.id == task_id).first()
+    if task is None:
+        raise HTTPException(status_code=404, detail="Task not found")
+
+    update_data = task_update.dict(exclude_unset=True)
+    for field, value in update_data.items():
+        setattr(task, field, value)
+
+    db.commit()
+    db.refresh(task)
+    return task
+
+
+@router.delete("/{task_id}", status_code=status.HTTP_204_NO_CONTENT)
+def delete_task(task_id: int, db: Session = Depends(get_db)):
+    task = db.query(Task).filter(Task.id == task_id).first()
+    if task is None:
+        raise HTTPException(status_code=404, detail="Task not found")
+
+    db.delete(task)
+    db.commit()
+    return None

app/db/base.py

@@ -0,0 +1,3 @@
+from sqlalchemy.ext.declarative import declarative_base
+
+Base = declarative_base()

app/db/session.py

@@ -0,0 +1,23 @@
+from pathlib import Path
+from sqlalchemy import create_engine
+from sqlalchemy.orm import sessionmaker
+
+
+DB_DIR = Path("/app") / "storage" / "db"
+DB_DIR.mkdir(parents=True, exist_ok=True)
+
+SQLALCHEMY_DATABASE_URL = f"sqlite:///{DB_DIR}/db.sqlite"
+
+engine = create_engine(
+    SQLALCHEMY_DATABASE_URL, connect_args={"check_same_thread": False}
+)
+
+SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
+
+
+def get_db():
+    db = SessionLocal()
+    try:
+        yield db
+    finally:
+        db.close()

app/models/__init__.py

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

app/models/task.py

@@ -0,0 +1,16 @@
+from datetime import datetime
+from sqlalchemy import Column, Integer, String, Text, Boolean, DateTime
+from app.db.base import Base
+
+
+class Task(Base):
+    __tablename__ = "tasks"
+
+    id = Column(Integer, primary_key=True, index=True)
+    title = Column(String, nullable=False, index=True)
+    description = Column(Text, nullable=True)
+    completed = Column(Boolean, default=False, nullable=False)
+    created_at = Column(DateTime, default=datetime.utcnow, nullable=False)
+    updated_at = Column(
+        DateTime, default=datetime.utcnow, onupdate=datetime.utcnow, nullable=False
+    )

app/schemas/__init__.py

@@ -0,0 +1,3 @@
+from .task import TaskBase, TaskCreate, TaskUpdate, TaskResponse
+
+__all__ = ["TaskBase", "TaskCreate", "TaskUpdate", "TaskResponse"]

app/schemas/task.py

@@ -0,0 +1,28 @@
+from datetime import datetime
+from typing import Optional
+from pydantic import BaseModel
+
+
+class TaskBase(BaseModel):
+    title: str
+    description: Optional[str] = None
+    completed: bool = False
+
+
+class TaskCreate(TaskBase):
+    pass
+
+
+class TaskUpdate(BaseModel):
+    title: Optional[str] = None
+    description: Optional[str] = None
+    completed: Optional[bool] = None
+
+
+class TaskResponse(TaskBase):
+    id: int
+    created_at: datetime
+    updated_at: datetime
+
+    class Config:
+        from_attributes = True

main.py

@@ -0,0 +1,35 @@
+from fastapi import FastAPI
+from fastapi.middleware.cors import CORSMiddleware
+
+from app.api.tasks import router as tasks_router
+from app.db.session import engine
+from app.db.base import Base
+
+app = FastAPI(
+    title="Task Manager API",
+    description="A simple Task Manager API built with FastAPI",
+    version="1.0.0",
+    openapi_url="/openapi.json",
+)
+
+app.add_middleware(
+    CORSMiddleware,
+    allow_origins=["*"],
+    allow_credentials=True,
+    allow_methods=["*"],
+    allow_headers=["*"],
+)
+
+Base.metadata.create_all(bind=engine)
+
+app.include_router(tasks_router, prefix="/api/tasks", tags=["tasks"])
+
+
+@app.get("/")
+def root():
+    return {"title": "Task Manager API", "documentation": "/docs", "health": "/health"}
+
+
+@app.get("/health")
+def health_check():
+    return {"status": "healthy", "service": "Task Manager API"}

requirements.txt

@@ -0,0 +1,7 @@
+fastapi==0.104.1
+uvicorn[standard]==0.24.0
+sqlalchemy==2.0.23
+alembic==1.12.1
+pydantic==2.5.0
+python-multipart==0.0.6
+ruff==0.1.6