Create a quick and simple FastAPI application with SQLite

This commit includes:
- Basic project structure with FastAPI
- SQLite database integration using SQLAlchemy
- CRUD API for items
- Alembic migrations setup
- Health check endpoint
- Proper error handling
- Updated README with setup instructions

README.md

@@ -1,3 +1,114 @@
-# FastAPI Application
+# QuickSimpleAPI
 
-This is a FastAPI application bootstrapped by BackendIM, the AI-powered backend generation platform.
+A quick and simple FastAPI application with SQLite database. This project provides a simple CRUD API for managing items.
+
+## Features
+
+- FastAPI framework with automatic API documentation
+- SQLite database integration
+- SQLAlchemy ORM
+- Alembic migrations
+- CORS support
+
+## Requirements
+
+- Python 3.8+
+- FastAPI
+- SQLAlchemy
+- Alembic
+- Uvicorn
+- Pydantic
+
+## Getting Started
+
+### Installation
+
+1. Clone the repository:
+
+```bash
+git clone https://github.com/yourusername/quicksimpleapi.git
+cd quicksimpleapi
+```
+
+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
+```
+
+The API will be available at `http://localhost:8000`.
+
+## API Documentation
+
+Once the application is running, you can access the API documentation at:
+
+- Swagger UI: `http://localhost:8000/docs`
+- ReDoc: `http://localhost:8000/redoc`
+
+## API Endpoints
+
+### Root Endpoint
+
+- `GET /`: Returns basic information about the API.
+
+### Health Check
+
+- `GET /health`: Returns the health status of the API.
+
+### Items API
+
+- `GET /api/v1/items`: Retrieve a list of items.
+- `POST /api/v1/items`: Create a new item.
+- `GET /api/v1/items/{item_id}`: Retrieve an item by ID.
+- `PUT /api/v1/items/{item_id}`: Update an item.
+- `DELETE /api/v1/items/{item_id}`: Delete an item.
+
+## Environment Variables
+
+The following environment variables can be set:
+
+- `SECRET_KEY`: Secret key for security. Default is "development_secret_key".
+
+## Project Structure
+
+```
+quicksimpleapi/
+├── app/
+│   ├── api/
+│   │   └── v1/
+│   │       ├── __init__.py
+│   │       └── items.py
+│   ├── core/
+│   │   ├── __init__.py
+│   │   └── config.py
+│   ├── db/
+│   │   ├── __init__.py
+│   │   ├── base.py
+│   │   └── session.py
+│   ├── models/
+│   │   ├── __init__.py
+│   │   └── item.py
+│   └── schemas/
+│       ├── __init__.py
+│       └── item.py
+├── migrations/
+│   ├── versions/
+│   │   └── 001_create_items_table.py
+│   ├── env.py
+│   └── script.py.mako
+├── main.py
+├── alembic.ini
+└── requirements.txt
+```

alembic.ini

@@ -0,0 +1,102 @@
+# A generic, single database configuration.
+
+[alembic]
+# path to migration scripts
+script_location = migrations
+
+# template used to generate migration files
+# file_template = %%(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; The path separator used here should not be the
+# same as in the filesystem.  '/' and ':' are good separators.
+# version_path_separator = :
+
+# the output encoding used when revision files
+# are written from script.py.mako
+# output_encoding = utf-8
+
+# SQLite URL example (absolute path needed for SQLite)
+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
+
+# lint with attempts to fix using "ruff" - use the exec runner, execute a binary
+# hooks = ruff
+# ruff.type = exec
+# ruff.executable = %(here)s/.venv/bin/ruff
+# ruff.options = --fix 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/__init__.py

@@ -0,0 +1,7 @@
+from fastapi import APIRouter
+
+from app.api.v1 import items
+
+api_router = APIRouter()
+
+api_router.include_router(items.router, prefix="/items", tags=["Items"])

app/api/v1/items.py

@@ -0,0 +1,92 @@
+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.item import Item as ItemModel
+from app.schemas.item import Item, ItemCreate, ItemUpdate
+
+router = APIRouter()
+
+
+@router.get("/", response_model=List[Item])
+def read_items(
+    skip: int = 0,
+    limit: int = 100,
+    db: Session = Depends(get_db)
+):
+    """
+    Retrieve items.
+    """
+    items = db.query(ItemModel).offset(skip).limit(limit).all()
+    return items
+
+
+@router.post("/", response_model=Item, status_code=status.HTTP_201_CREATED)
+def create_item(
+    item_in: ItemCreate,
+    db: Session = Depends(get_db)
+):
+    """
+    Create new item.
+    """
+    db_item = ItemModel(**item_in.model_dump())
+    db.add(db_item)
+    db.commit()
+    db.refresh(db_item)
+    return db_item
+
+
+@router.get("/{item_id}", response_model=Item)
+def read_item(
+    item_id: int,
+    db: Session = Depends(get_db)
+):
+    """
+    Get item by ID.
+    """
+    db_item = db.query(ItemModel).filter(ItemModel.id == item_id).first()
+    if db_item is None:
+        raise HTTPException(status_code=404, detail="Item not found")
+    return db_item
+
+
+@router.put("/{item_id}", response_model=Item)
+def update_item(
+    item_id: int,
+    item_in: ItemUpdate,
+    db: Session = Depends(get_db)
+):
+    """
+    Update an item.
+    """
+    db_item = db.query(ItemModel).filter(ItemModel.id == item_id).first()
+    if db_item is None:
+        raise HTTPException(status_code=404, detail="Item not found")
+    
+    update_data = item_in.model_dump(exclude_unset=True)
+    for field, value in update_data.items():
+        setattr(db_item, field, value)
+    
+    db.add(db_item)
+    db.commit()
+    db.refresh(db_item)
+    return db_item
+
+
+@router.delete("/{item_id}", status_code=status.HTTP_204_NO_CONTENT, response_model=None)
+def delete_item(
+    item_id: int,
+    db: Session = Depends(get_db)
+):
+    """
+    Delete an item.
+    """
+    db_item = db.query(ItemModel).filter(ItemModel.id == item_id).first()
+    if db_item is None:
+        raise HTTPException(status_code=404, detail="Item not found")
+    
+    db.delete(db_item)
+    db.commit()
+    return None

app/core/config.py

@@ -0,0 +1,29 @@
+import os
+from pathlib import Path
+
+from pydantic_settings import BaseSettings, SettingsConfigDict
+
+class Settings(BaseSettings):
+    # Project settings
+    PROJECT_NAME: str = "QuickSimpleAPI"
+    PROJECT_DESCRIPTION: str = "A quick and simple FastAPI application"
+    VERSION: str = "0.1.0"
+    
+    # Database settings
+    DB_DIR: Path = Path("/app") / "storage" / "db"
+    DATABASE_URL: str = f"sqlite:///{DB_DIR}/db.sqlite"
+    
+    # Security settings
+    SECRET_KEY: str = os.environ.get("SECRET_KEY", "development_secret_key")
+    
+    model_config = SettingsConfigDict(
+        env_file=".env",
+        env_file_encoding="utf-8",
+        case_sensitive=True,
+    )
+
+# Create an instance of the settings
+settings = Settings()
+
+# Ensure DB directory exists
+settings.DB_DIR.mkdir(parents=True, exist_ok=True)

app/db/base.py

@@ -0,0 +1,4 @@
+from sqlalchemy.ext.declarative import declarative_base
+
+# Create a Base class for SQLAlchemy models
+Base = declarative_base()

app/db/session.py

@@ -0,0 +1,28 @@
+from pathlib import Path
+
+from sqlalchemy import create_engine
+from sqlalchemy.orm import sessionmaker
+
+# Create DB directory
+DB_DIR = Path("/app") / "storage" / "db"
+DB_DIR.mkdir(parents=True, exist_ok=True)
+
+# Define SQLAlchemy database URL
+SQLALCHEMY_DATABASE_URL = f"sqlite:///{DB_DIR}/db.sqlite"
+
+# Create SQLAlchemy engine
+engine = create_engine(
+    SQLALCHEMY_DATABASE_URL,
+    connect_args={"check_same_thread": False}
+)
+
+# Create SessionLocal class
+SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
+
+# Define dependency to get DB session
+def get_db():
+    db = SessionLocal()
+    try:
+        yield db
+    finally:
+        db.close()

app/models/__init__.py

@@ -0,0 +1 @@
+from app.models.item import Item  # noqa: F401

app/models/item.py

@@ -0,0 +1,14 @@
+from sqlalchemy import Column, Integer, String, Boolean, DateTime
+from sqlalchemy.sql import func
+
+from app.db.base import Base
+
+class Item(Base):
+    __tablename__ = "items"
+    
+    id = Column(Integer, primary_key=True, index=True)
+    name = Column(String, index=True, nullable=False)
+    description = Column(String, nullable=True)
+    is_active = Column(Boolean, default=True)
+    created_at = Column(DateTime(timezone=True), server_default=func.now())
+    updated_at = Column(DateTime(timezone=True), onupdate=func.now())

app/schemas/__init__.py

@@ -0,0 +1 @@
+from app.schemas.item import Item, ItemCreate, ItemUpdate  # noqa: F401

app/schemas/item.py

@@ -0,0 +1,38 @@
+from datetime import datetime
+from typing import Optional
+
+from pydantic import BaseModel
+
+
+class ItemBase(BaseModel):
+    """Base schema for Item."""
+    name: str
+    description: Optional[str] = None
+    is_active: bool = True
+
+
+class ItemCreate(ItemBase):
+    """Schema for creating a new Item."""
+    pass
+
+
+class ItemUpdate(BaseModel):
+    """Schema for updating an Item."""
+    name: Optional[str] = None
+    description: Optional[str] = None
+    is_active: Optional[bool] = None
+
+
+class ItemInDBBase(ItemBase):
+    """Base schema for Item in DB."""
+    id: int
+    created_at: datetime
+    updated_at: Optional[datetime] = None
+
+    class Config:
+        from_attributes = True
+
+
+class Item(ItemInDBBase):
+    """Schema for an Item."""
+    pass

main.py

@@ -0,0 +1,48 @@
+import uvicorn
+from fastapi import FastAPI
+from fastapi.middleware.cors import CORSMiddleware
+
+from app.api.v1 import api_router
+from app.core.config import settings
+
+app = FastAPI(
+    title=settings.PROJECT_NAME,
+    description=settings.PROJECT_DESCRIPTION,
+    version=settings.VERSION,
+    openapi_url="/openapi.json",
+    docs_url="/docs",
+    redoc_url="/redoc",
+)
+
+# Add CORS middleware
+app.add_middleware(
+    CORSMiddleware,
+    allow_origins=["*"],
+    allow_credentials=True,
+    allow_methods=["*"],
+    allow_headers=["*"],
+)
+
+# Include API router
+app.include_router(api_router, prefix="/api/v1")
+
+@app.get("/", tags=["Root"])
+async def root():
+    """
+    Root endpoint that returns basic information about the API.
+    """
+    return {
+        "title": settings.PROJECT_NAME,
+        "docs": "/docs",
+        "health": "/health"
+    }
+
+@app.get("/health", tags=["Health"])
+async def health_check():
+    """
+    Health check endpoint to verify if the API is running.
+    """
+    return {"status": "healthy"}
+
+if __name__ == "__main__":
+    uvicorn.run("main:app", host="0.0.0.0", port=8000, reload=True)

migrations/env.py

@@ -0,0 +1,78 @@
+from logging.config import fileConfig
+
+from app.db.base import Base
+from alembic import context
+from sqlalchemy import engine_from_config, pool
+
+# 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,  # Key configuration 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/001_create_items_table.py

@@ -0,0 +1,37 @@
+"""create items table
+
+Revision ID: 001
+Revises: 
+Create Date: 2023-08-15 10:00:00.000000
+
+"""
+from alembic import op
+import sqlalchemy as sa
+from sqlalchemy.sql import func
+
+# revision identifiers, used by Alembic.
+revision = '001'
+down_revision = None
+branch_labels = None
+depends_on = None
+
+
+def upgrade() -> None:
+    op.create_table(
+        'items',
+        sa.Column('id', sa.Integer(), nullable=False),
+        sa.Column('name', sa.String(), nullable=False),
+        sa.Column('description', sa.String(), nullable=True),
+        sa.Column('is_active', sa.Boolean(), default=True),
+        sa.Column('created_at', sa.DateTime(timezone=True), server_default=func.now()),
+        sa.Column('updated_at', sa.DateTime(timezone=True), onupdate=func.now()),
+        sa.PrimaryKeyConstraint('id'),
+    )
+    op.create_index(op.f('ix_items_id'), 'items', ['id'], unique=False)
+    op.create_index(op.f('ix_items_name'), 'items', ['name'], unique=False)
+
+
+def downgrade() -> None:
+    op.drop_index(op.f('ix_items_name'), table_name='items')
+    op.drop_index(op.f('ix_items_id'), table_name='items')
+    op.drop_table('items')

requirements.txt

@@ -0,0 +1,7 @@
+fastapi>=0.68.0
+uvicorn>=0.15.0
+pydantic>=2.0.0
+sqlalchemy>=2.0.0
+alembic>=1.7.5
+python-dotenv>=0.19.1
+ruff>=0.1.0