Create FastAPI REST API with SQLite

Features:
- Project structure setup
- Database configuration with SQLAlchemy
- Item model and CRUD operations
- API endpoints for items
- Alembic migrations
- Health check endpoint
- Comprehensive documentation

generated with BackendIM... (backend.im)

README.md

@@ -1,3 +1,67 @@
-# FastAPI Application
+# Generic REST API Service
 
-This is a FastAPI application bootstrapped by BackendIM, the AI-powered backend generation platform.
+A modern REST API service built with FastAPI and SQLite, providing a clean architecture and RESTful endpoints.
+
+## Features
+
+- Fast and efficient API with FastAPI
+- SQLite database with SQLAlchemy ORM
+- Database migrations with Alembic
+- Pydantic schemas for validation
+- Health check endpoint
+- Full CRUD operations for items
+- OpenAPI documentation
+
+## Project Structure
+
+```
+.
+├── app                     # Application package
+│   ├── database.py         # Database configuration
+│   ├── models              # SQLAlchemy models
+│   ├── routes              # API routes and endpoints
+│   └── schemas             # Pydantic schemas
+├── migrations              # Alembic migrations
+├── alembic.ini             # Alembic configuration
+├── main.py                 # Application entry point
+└── requirements.txt        # Project dependencies
+```
+
+## API Endpoints
+
+- `GET /health` - Health check endpoint
+- `GET /api/v1/items` - List all items
+- `GET /api/v1/items/{item_id}` - Get a specific item
+- `POST /api/v1/items` - Create a new item
+- `PUT /api/v1/items/{item_id}` - Update an item
+- `DELETE /api/v1/items/{item_id}` - Delete an item
+
+## API Documentation
+
+Once the application is running, you can access the API documentation:
+
+- Swagger UI - `/docs`
+- ReDoc - `/redoc`
+
+## Development
+
+### Requirements
+
+- Python 3.8+
+- SQLite
+
+### Setup
+
+1. Install dependencies:
+
+```bash
+pip install -r requirements.txt
+```
+
+2. Run the application:
+
+```bash
+uvicorn main:app --reload
+```
+
+The API will be available at http://localhost:8000.

alembic.ini

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+# 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
+
+# timezone to use when rendering the date
+# within the migration file as well as the filename.
+# 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
+# version_locations = %(here)s/bar %(here)s/bat migrations/versions
+
+# the output encoding used when revision files
+# are written from script.py.mako
+# output_encoding = utf-8
+
+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
+
+# 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/__init__.py

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+# app package

app/database.py

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+from sqlalchemy import create_engine
+from sqlalchemy.ext.declarative import declarative_base
+from sqlalchemy.orm import sessionmaker
+from pathlib import Path
+
+# Create directory for database
+DB_DIR = Path("/app") / "storage" / "db"
+DB_DIR.mkdir(parents=True, exist_ok=True)
+
+# SQLite database URL
+SQLALCHEMY_DATABASE_URL = f"sqlite:///{DB_DIR}/db.sqlite"
+
+# Create engine
+engine = create_engine(
+    SQLALCHEMY_DATABASE_URL,
+    connect_args={"check_same_thread": False}
+)
+
+# Create session
+SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
+
+# Create base model class
+Base = declarative_base()
+
+# Dependency for database sessions
+def get_db():
+    db = SessionLocal()
+    try:
+        yield db
+    finally:
+        db.close()

app/models/__init__.py

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+from app.models.item import Item
+
+# Add all models here
+__all__ = ["Item"]

app/models/item.py

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+from sqlalchemy import Column, Integer, String, Boolean, DateTime, Text
+from sqlalchemy.sql import func
+from app.database import Base
+
+class Item(Base):
+    __tablename__ = "items"
+    
+    id = Column(Integer, primary_key=True, index=True)
+    name = Column(String(100), nullable=False)
+    description = Column(Text, nullable=True)
+    price = Column(Integer, nullable=False)  # Price in cents
+    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/routes/__init__.py

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+from app.routes import health, api
+
+__all__ = ["health", "api"]

app/routes/api.py

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+from fastapi import APIRouter, Depends, HTTPException, status
+from sqlalchemy.orm import Session
+from typing import List
+from app.database import get_db
+from app.models.item import Item
+from app.schemas.item import ItemCreate, ItemUpdate, ItemResponse
+
+router = APIRouter(tags=["Items"])
+
+@router.post("/items", response_model=ItemResponse, status_code=status.HTTP_201_CREATED)
+def create_item(item: ItemCreate, db: Session = Depends(get_db)):
+    """
+    Create a new item.
+    """
+    db_item = Item(
+        name=item.name,
+        description=item.description,
+        price=item.price,
+        is_active=item.is_active
+    )
+    db.add(db_item)
+    db.commit()
+    db.refresh(db_item)
+    return db_item
+
+@router.get("/items", response_model=List[ItemResponse])
+def read_items(skip: int = 0, limit: int = 100, db: Session = Depends(get_db)):
+    """
+    Retrieve items.
+    """
+    items = db.query(Item).offset(skip).limit(limit).all()
+    return items
+
+@router.get("/items/{item_id}", response_model=ItemResponse)
+def read_item(item_id: int, db: Session = Depends(get_db)):
+    """
+    Get a specific item by ID.
+    """
+    db_item = db.query(Item).filter(Item.id == item_id).first()
+    if db_item is None:
+        raise HTTPException(status_code=404, detail="Item not found")
+    return db_item
+
+@router.put("/items/{item_id}", response_model=ItemResponse)
+def update_item(item_id: int, item: ItemUpdate, db: Session = Depends(get_db)):
+    """
+    Update an item.
+    """
+    db_item = db.query(Item).filter(Item.id == item_id).first()
+    if db_item is None:
+        raise HTTPException(status_code=404, detail="Item not found")
+    
+    update_data = item.dict(exclude_unset=True)
+    for key, value in update_data.items():
+        setattr(db_item, key, value)
+    
+    db.commit()
+    db.refresh(db_item)
+    return db_item
+
+@router.delete("/items/{item_id}", status_code=status.HTTP_204_NO_CONTENT)
+def delete_item(item_id: int, db: Session = Depends(get_db)):
+    """
+    Delete an item.
+    """
+    db_item = db.query(Item).filter(Item.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/routes/health.py

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+from fastapi import APIRouter, Depends
+from sqlalchemy.orm import Session
+from app.database import get_db
+
+router = APIRouter(tags=["Health"])
+
+@router.get("/health", summary="Health check endpoint")
+def health_check(db: Session = Depends(get_db)):
+    """
+    Health check endpoint that returns the status of the API and database connection.
+    """
+    health_status = {
+        "status": "healthy",
+        "database": "connected" 
+    }
+    
+    try:
+        # Test database connection
+        db.execute("SELECT 1")
+    except Exception:
+        health_status["database"] = "disconnected"
+        health_status["status"] = "unhealthy"
+    
+    return health_status

app/schemas/__init__.py

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+from app.schemas.item import ItemBase, ItemCreate, ItemUpdate, ItemInDB, ItemResponse
+
+# Add all schemas here
+__all__ = ["ItemBase", "ItemCreate", "ItemUpdate", "ItemInDB", "ItemResponse"]

app/schemas/item.py

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+from pydantic import BaseModel, Field
+from typing import Optional
+from datetime import datetime
+
+class ItemBase(BaseModel):
+    name: str = Field(..., min_length=1, max_length=100, example="Example Item")
+    description: Optional[str] = Field(None, example="This is an example item description")
+    price: int = Field(..., gt=0, example=1999)  # Price in cents (e.g., 19.99 USD = 1999)
+    is_active: bool = Field(True, example=True)
+
+class ItemCreate(ItemBase):
+    pass
+
+class ItemUpdate(BaseModel):
+    name: Optional[str] = Field(None, min_length=1, max_length=100, example="Updated Item")
+    description: Optional[str] = Field(None, example="This is an updated description")
+    price: Optional[int] = Field(None, gt=0, example=2499)
+    is_active: Optional[bool] = Field(None, example=True)
+
+class ItemInDB(ItemBase):
+    id: int
+    created_at: datetime
+    updated_at: Optional[datetime] = None
+
+    class Config:
+        from_attributes = True
+
+class ItemResponse(ItemInDB):
+    """Response model for items"""
+    pass

main.py

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+from fastapi import FastAPI
+from fastapi.middleware.cors import CORSMiddleware
+from pathlib import Path
+
+from app.routes import health, api
+from app.database import engine, Base
+
+# Create database tables
+Base.metadata.create_all(bind=engine)
+
+app = FastAPI(title="Generic REST API Service", 
+              description="A generic REST API service built with FastAPI and SQLite",
+              version="0.1.0")
+
+# Add CORS middleware
+app.add_middleware(
+    CORSMiddleware,
+    allow_origins=["*"],
+    allow_credentials=True,
+    allow_methods=["*"],
+    allow_headers=["*"],
+)
+
+# Include routers
+app.include_router(health.router)
+app.include_router(api.router, prefix="/api/v1")
+
+if __name__ == "__main__":
+    import uvicorn
+    uvicorn.run("main:app", host="0.0.0.0", port=8000, reload=True)

migrations/__init__.py

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+# migrations package

migrations/env.py

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+from logging.config import fileConfig
+from sqlalchemy import engine_from_config
+from sqlalchemy import pool
+from alembic import context
+from pathlib import Path
+
+# 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.
+fileConfig(config.config_file_name)
+
+# add your model's MetaData object here
+# for 'autogenerate' support
+from app.database import Base
+import app.models  # Import all models
+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():
+    """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():
+    """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:
+        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()

migrations/script.py.mako

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+"""${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():
+    ${upgrades if upgrades else "pass"}
+
+
+def downgrade():
+    ${downgrades if downgrades else "pass"}

migrations/versions/2fbbf2d05a82_initial_migration.py

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+"""Initial migration
+
+Revision ID: 2fbbf2d05a82
+Revises: 
+Create Date: 2025-05-14 12:00:00.000000
+
+"""
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision = '2fbbf2d05a82'
+down_revision = None
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    # Create items table
+    op.create_table('items',
+        sa.Column('id', sa.Integer(), nullable=False),
+        sa.Column('name', sa.String(length=100), nullable=False),
+        sa.Column('description', sa.Text(), nullable=True),
+        sa.Column('price', sa.Integer(), nullable=False),
+        sa.Column('is_active', sa.Boolean(), nullable=False, server_default=sa.text('1')),
+        sa.Column('created_at', sa.DateTime(timezone=True), server_default=sa.text('(CURRENT_TIMESTAMP)')),
+        sa.Column('updated_at', sa.DateTime(timezone=True), nullable=True),
+        sa.PrimaryKeyConstraint('id')
+    )
+    op.create_index(op.f('ix_items_id'), 'items', ['id'], unique=False)
+
+
+def downgrade():
+    op.drop_index(op.f('ix_items_id'), table_name='items')
+    op.drop_table('items')

requirements.txt

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+fastapi==0.104.1
+uvicorn==0.24.0
+sqlalchemy==2.0.23
+pydantic==2.4.2
+alembic==1.12.1
+ruff==0.1.5