Add FastAPI REST API with SQLite database

- Set up project structure
- Add database models and SQLAlchemy setup
- Configure Alembic for migrations
- Create API endpoints for items
- Add health check endpoint
- Update documentation

generated with BackendIM... (backend.im)

Co-Authored-By: Claude <noreply@anthropic.com>

README.md

@@ -1,3 +1,91 @@
-# FastAPI Application
+# Generic REST API Service
 
-This is a FastAPI application bootstrapped by BackendIM, the AI-powered backend generation platform.
+A modern, production-ready REST API service built with FastAPI and SQLite.
+
+## Features
+
+- FastAPI framework for high performance
+- SQLAlchemy ORM with SQLite database
+- Alembic migrations
+- Pydantic for data validation
+- Automatic API documentation (Swagger UI and ReDoc)
+- Health check endpoint
+- CRUD operations for items
+- Project structure optimized for scaling
+
+## Getting Started
+
+### Prerequisites
+
+- Python 3.8+
+- Git
+
+### Installation
+
+1. Clone the repository:
+```bash
+git clone <repository-url>
+cd genericrestapiservice
+```
+
+2. Create a virtual environment and activate it:
+```bash
+python -m venv venv
+source venv/bin/activate  # On Windows: venv\Scripts\activate
+```
+
+3. Install dependencies:
+```bash
+pip install -r requirements.txt
+```
+
+4. Run migrations:
+```bash
+alembic upgrade head
+```
+
+5. Start the application:
+```bash
+uvicorn main:app --reload
+```
+
+The API will be available at http://localhost:8000
+
+## API Documentation
+
+- Swagger UI: http://localhost:8000/docs
+- ReDoc: http://localhost:8000/redoc
+
+## Project Structure
+
+```
+.
+├── alembic/                  # Database migrations
+│   ├── versions/             # Migration versions
+│   ├── env.py                # Alembic environment
+│   └── script.py.mako        # Migration script template
+├── app/                      # Application package
+│   ├── api/                  # API endpoints
+│   │   ├── v1/               # API v1
+│   │   │   └── endpoints/    # API endpoints by resource
+│   │   └── api.py            # API router setup
+│   ├── core/                 # Core application code
+│   │   └── config.py         # Application configuration
+│   ├── crud/                 # CRUD operations
+│   ├── database/             # Database setup
+│   │   └── session.py        # DB session management
+│   ├── models/               # SQLAlchemy models
+│   └── schemas/              # Pydantic schemas
+├── alembic.ini               # Alembic configuration
+├── main.py                   # Application entry point
+└── requirements.txt          # Project dependencies
+```
+
+## API Endpoints
+
+- `GET /api/v1/health`: Health check endpoint
+- `GET /api/v1/items`: List all items
+- `POST /api/v1/items`: Create a new item
+- `GET /api/v1/items/{item_id}`: Get a specific item
+- `PUT /api/v1/items/{item_id}`: Update a specific item
+- `DELETE /api/v1/items/{item_id}`: Delete a specific item

alembic.ini

@@ -0,0 +1,102 @@
+# A generic, single database configuration.
+
+[alembic]
+# path to migration scripts
+script_location = alembic
+
+# 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 alembic/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:alembic/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
+
+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

alembic/env.py

@@ -0,0 +1,80 @@
+from logging.config import fileConfig
+
+from sqlalchemy import engine_from_config
+from sqlalchemy import pool
+
+from alembic import context
+
+# 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 myapp import mymodel
+# target_metadata = mymodel.Base.metadata
+from app.database.session import Base
+from app.models import Item
+
+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()

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

alembic/versions/001_create_items_table.py

@@ -0,0 +1,39 @@
+"""create items table
+
+Revision ID: 001
+Revises: 
+Create Date: 2025-05-15
+
+"""
+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():
+    # Create items table
+    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(), nullable=False, default=True),
+        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)
+    op.create_index(op.f('ix_items_name'), 'items', ['name'], unique=False)
+
+
+def downgrade():
+    # Drop items table
+    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')

app/api/api.py

@@ -0,0 +1,35 @@
+from fastapi import FastAPI, APIRouter
+from fastapi.middleware.cors import CORSMiddleware
+
+from app.core.config import settings
+from app.api.v1.endpoints import health, items
+
+# Create FastAPI app
+app = FastAPI(
+    title=settings.PROJECT_NAME,
+    description=settings.DESCRIPTION,
+    version=settings.VERSION,
+    openapi_url=f"{settings.API_V1_STR}/openapi.json",
+    docs_url="/docs",
+    redoc_url="/redoc",
+)
+
+# Set up CORS
+if settings.BACKEND_CORS_ORIGINS:
+    app.add_middleware(
+        CORSMiddleware,
+        allow_origins=[str(origin) for origin in settings.BACKEND_CORS_ORIGINS],
+        allow_credentials=True,
+        allow_methods=["*"],
+        allow_headers=["*"],
+    )
+
+# Create API router
+api_router = APIRouter()
+
+# Include routers from endpoints
+api_router.include_router(health.router, prefix="/health", tags=["health"])
+api_router.include_router(items.router, prefix="/items", tags=["items"])
+
+# Add API router to app
+app.include_router(api_router, prefix=settings.API_V1_STR)

app/api/v1/endpoints/health.py

@@ -0,0 +1,25 @@
+from fastapi import APIRouter, Depends
+from sqlalchemy.orm import Session
+
+from app.database.session import get_db
+
+router = APIRouter()
+
+
+@router.get("", response_model=dict)
+def health_check(db: Session = Depends(get_db)):
+    """
+    Health check endpoint to verify API and database are working
+    """
+    try:
+        # Check if DB connection is working
+        db.execute("SELECT 1")
+        return {
+            "status": "ok",
+            "message": "API is healthy and database connection is working"
+        }
+    except Exception as e:
+        return {
+            "status": "error",
+            "message": f"Database connection failed: {str(e)}"
+        }

app/api/v1/endpoints/items.py

@@ -0,0 +1,93 @@
+from typing import Any, List, Optional
+
+from fastapi import APIRouter, Depends, HTTPException, Query
+from sqlalchemy.orm import Session
+
+from app import crud
+from app.database.session import get_db
+from app.schemas.item import Item, ItemCreate, ItemUpdate
+
+router = APIRouter()
+
+
+@router.get("", response_model=List[Item])
+def read_items(
+    db: Session = Depends(get_db),
+    skip: int = 0,
+    limit: int = 100,
+) -> Any:
+    """
+    Retrieve items.
+    """
+    items = crud.get_multi(db, skip=skip, limit=limit)
+    return items
+
+
+@router.post("", response_model=Item)
+def create_item(
+    *,
+    db: Session = Depends(get_db),
+    item_in: ItemCreate,
+) -> Any:
+    """
+    Create new item.
+    """
+    item = crud.create(db=db, obj_in=item_in)
+    return item
+
+
+@router.get("/{item_id}", response_model=Item)
+def read_item(
+    *,
+    db: Session = Depends(get_db),
+    item_id: int,
+) -> Any:
+    """
+    Get item by ID.
+    """
+    item = crud.get(db=db, item_id=item_id)
+    if not item:
+        raise HTTPException(
+            status_code=404,
+            detail="Item not found",
+        )
+    return item
+
+
+@router.put("/{item_id}", response_model=Item)
+def update_item(
+    *,
+    db: Session = Depends(get_db),
+    item_id: int,
+    item_in: ItemUpdate,
+) -> Any:
+    """
+    Update an item.
+    """
+    item = crud.get(db=db, item_id=item_id)
+    if not item:
+        raise HTTPException(
+            status_code=404,
+            detail="Item not found",
+        )
+    item = crud.update(db=db, db_obj=item, obj_in=item_in)
+    return item
+
+
+@router.delete("/{item_id}", response_model=Item)
+def delete_item(
+    *,
+    db: Session = Depends(get_db),
+    item_id: int,
+) -> Any:
+    """
+    Delete an item.
+    """
+    item = crud.get(db=db, item_id=item_id)
+    if not item:
+        raise HTTPException(
+            status_code=404,
+            detail="Item not found",
+        )
+    item = crud.remove(db=db, item_id=item_id)
+    return item

app/core/config.py

@@ -0,0 +1,26 @@
+from pydantic_settings import BaseSettings
+from pathlib import Path
+
+
+class Settings(BaseSettings):
+    API_V1_STR: str = "/api/v1"
+    PROJECT_NAME: str = "Generic REST API Service"
+    DESCRIPTION: str = "A generic REST API service built with FastAPI and SQLite"
+    VERSION: str = "0.1.0"
+    
+    # CORS
+    BACKEND_CORS_ORIGINS: list[str] = ["*"]
+    
+    # Server settings
+    HOST: str = "0.0.0.0"
+    PORT: int = 8000
+    RELOAD: bool = True
+    
+    # Database
+    DB_DIR = Path("/app") / "storage" / "db"
+    
+    class Config:
+        case_sensitive = True
+
+
+settings = Settings()

app/crud/__init__.py

@@ -0,0 +1 @@
+from app.crud.item import get, get_by_name, get_multi, create, update, remove  # noqa

app/crud/item.py

@@ -0,0 +1,52 @@
+from typing import List, Optional
+
+from sqlalchemy.orm import Session
+
+from app.models.item import Item
+from app.schemas.item import ItemCreate, ItemUpdate
+
+
+def get(db: Session, item_id: int) -> Optional[Item]:
+    return db.query(Item).filter(Item.id == item_id).first()
+
+
+def get_by_name(db: Session, name: str) -> Optional[Item]:
+    return db.query(Item).filter(Item.name == name).first()
+
+
+def get_multi(
+    db: Session, *, skip: int = 0, limit: int = 100
+) -> List[Item]:
+    return db.query(Item).offset(skip).limit(limit).all()
+
+
+def create(db: Session, *, obj_in: ItemCreate) -> Item:
+    db_obj = Item(
+        name=obj_in.name,
+        description=obj_in.description,
+        is_active=obj_in.is_active,
+    )
+    db.add(db_obj)
+    db.commit()
+    db.refresh(db_obj)
+    return db_obj
+
+
+def update(
+    db: Session, *, db_obj: Item, obj_in: ItemUpdate
+) -> Item:
+    update_data = obj_in.model_dump(exclude_unset=True)
+    for field in update_data:
+        setattr(db_obj, field, update_data[field])
+    db.add(db_obj)
+    db.commit()
+    db.refresh(db_obj)
+    return db_obj
+
+
+def remove(db: Session, *, item_id: int) -> Optional[Item]:
+    obj = db.query(Item).get(item_id)
+    if obj:
+        db.delete(obj)
+        db.commit()
+    return obj

app/database/session.py

@@ -0,0 +1,29 @@
+from sqlalchemy import create_engine
+from sqlalchemy.ext.declarative import declarative_base
+from sqlalchemy.orm import sessionmaker
+
+from app.core.config import settings
+
+# Create directory if it doesn't exist
+settings.DB_DIR.mkdir(parents=True, exist_ok=True)
+
+SQLALCHEMY_DATABASE_URL = f"sqlite:///{settings.DB_DIR}/db.sqlite"
+
+engine = create_engine(
+    SQLALCHEMY_DATABASE_URL,
+    connect_args={"check_same_thread": False}
+)
+SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
+
+Base = declarative_base()
+
+
+def get_db():
+    """
+    Dependency for getting DB session
+    """
+    db = SessionLocal()
+    try:
+        yield db
+    finally:
+        db.close()

app/models/__init__.py

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

app/models/item.py

@@ -0,0 +1,15 @@
+from sqlalchemy import Column, Integer, String, Boolean, DateTime
+from sqlalchemy.sql import func
+
+from app.database.session import Base
+
+
+class Item(Base):
+    __tablename__ = "items"
+
+    id = Column(Integer, primary_key=True, index=True)
+    name = Column(String, index=True)
+    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, ItemInDB  # noqa

app/schemas/item.py

@@ -0,0 +1,42 @@
+from datetime import datetime
+from typing import Optional
+
+from pydantic import BaseModel
+
+
+# Shared properties
+class ItemBase(BaseModel):
+    name: str
+    description: Optional[str] = None
+    is_active: Optional[bool] = True
+
+
+# Properties to receive on item creation
+class ItemCreate(ItemBase):
+    pass
+
+
+# Properties to receive on item update
+class ItemUpdate(ItemBase):
+    name: Optional[str] = None
+    is_active: Optional[bool] = None
+
+
+# Properties shared by models stored in DB
+class ItemInDBBase(ItemBase):
+    id: int
+    created_at: datetime
+    updated_at: Optional[datetime] = None
+
+    class Config:
+        from_attributes = True
+
+
+# Properties to return to client
+class Item(ItemInDBBase):
+    pass
+
+
+# Properties stored in DB
+class ItemInDB(ItemInDBBase):
+    pass

main.py

@@ -0,0 +1,11 @@
+import uvicorn
+from app.core.config import settings
+from app.api.api import app
+
+if __name__ == "__main__":
+    uvicorn.run(
+        "main:app",
+        host=settings.HOST,
+        port=settings.PORT,
+        reload=settings.RELOAD,
+    )

requirements.txt

@@ -0,0 +1,9 @@
+fastapi==0.109.0
+uvicorn==0.27.0
+sqlalchemy==2.0.25
+alembic==1.13.1
+pydantic==2.5.3
+pydantic-settings==2.1.0
+python-multipart==0.0.6
+email-validator==2.1.0
+ruff==0.2.0