Create FastAPI endpoint service

- Set up FastAPI project structure with best practices
- Implemented SQLAlchemy models with SQLite database
- Added Alembic for database migrations
- Created CRUD API endpoints for items
- Added health check endpoint
- Updated documentation

generated with BackendIM... (backend.im)

README.md

@@ -1,3 +1,71 @@
-# FastAPI Application
+# FastAPI Endpoint Service
 
 This is a FastAPI application bootstrapped by BackendIM, the AI-powered backend generation platform.
+
+## Features
+
+- Fast API endpoints with FastAPI framework
+- SQLite database with SQLAlchemy ORM
+- Database migrations with Alembic
+- Health endpoint for monitoring
+- CRUD operations for items
+- Input validation with Pydantic
+- Interactive API documentation with Swagger UI and ReDoc
+
+## Project Structure
+
+```
+├── alembic/              # Database migration files
+├── app/                  # Application source code
+│   ├── api/              # API endpoints
+│   │   ├── endpoints/    # API route handlers
+│   │   └── dependencies/ # API dependencies
+│   ├── core/             # Core application modules
+│   ├── models/           # SQLAlchemy models
+│   └── schemas/          # Pydantic schemas
+├── main.py               # Application entry point
+└── requirements.txt      # Project dependencies
+```
+
+## Installation
+
+1. Clone the repository
+2. Install dependencies:
+
+```bash
+pip install -r requirements.txt
+```
+
+## Running the Application
+
+```bash
+uvicorn main:app --host 0.0.0.0 --port 8000 --reload
+```
+
+## API Documentation
+
+API documentation is available at:
+
+- Swagger UI: [http://localhost:8000/docs](http://localhost:8000/docs)
+- ReDoc: [http://localhost:8000/redoc](http://localhost:8000/redoc)
+
+## API Endpoints
+
+- `GET /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 an item
+- `DELETE /api/v1/items/{item_id}`: Delete an item
+
+## Database Migrations
+
+Run the following commands to apply or create migrations:
+
+```bash
+# Apply migrations
+alembic upgrade head
+
+# Create a new migration
+alembic revision --autogenerate -m "Migration message"
+```

alembic.ini

@@ -0,0 +1,108 @@
+# 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.
+
+# set to 'true' to search source files recursively
+# in each "version_locations" directory
+# new in Alembic version 1.10
+# recursive_version_locations = false
+
+# the output encoding used when revision files
+# are written from script.py.mako
+# output_encoding = utf-8
+
+# SQLite URL example
+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/README

@@ -0,0 +1 @@
+Generic single-database configuration with SQLAlchemy.

alembic/env.py

@@ -0,0 +1,86 @@
+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.
+if config.config_file_name is not None:
+    fileConfig(config.config_file_name)
+
+# add your model's MetaData object here
+# for 'autogenerate' support
+# from myapp import mymodel
+# target_metadata = mymodel.Base.metadata
+import sys
+from pathlib import Path
+
+sys.path.insert(0, str(Path(__file__).resolve().parents[1]))
+
+from app.core.database import Base
+from app.models import Item  # Import all models here
+
+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:
+        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 +1,26 @@
+"""${message}
+
+Revision ID: ${up_revision}
+Revises: ${down_revision | comma,n}
+Create Date: ${create_date}
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+${imports if imports else ""}
+
+# revision identifiers, used by Alembic.
+revision: str = ${repr(up_revision)}
+down_revision: Union[str, None] = ${repr(down_revision)}
+branch_labels: Union[str, Sequence[str], None] = ${repr(branch_labels)}
+depends_on: Union[str, Sequence[str], None] = ${repr(depends_on)}
+
+
+def upgrade() -> None:
+    ${upgrades if upgrades else "pass"}
+
+
+def downgrade() -> None:
+    ${downgrades if downgrades else "pass"}

alembic/versions/85bcd3a99d15_initial_migration.py

@@ -0,0 +1,39 @@
+"""Initial migration
+
+Revision ID: 85bcd3a99d15
+Revises: 
+Create Date: 2023-05-13 00:00:00.000000
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision: str = '85bcd3a99d15'
+down_revision: Union[str, None] = None
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    # Create items table
+    op.create_table(
+        'items',
+        sa.Column('id', sa.Integer(), nullable=False),
+        sa.Column('created_at', sa.DateTime(), nullable=False),
+        sa.Column('updated_at', sa.DateTime(), nullable=False),
+        sa.Column('name', sa.String(length=255), nullable=False),
+        sa.Column('description', sa.Text(), 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() -> 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')

app/api/endpoints/__init__.py

@@ -0,0 +1,7 @@
+from fastapi import APIRouter
+from app.api.endpoints import health, items
+
+api_router = APIRouter()
+
+# Include routers
+api_router.include_router(items.router, tags=["Items"])

app/api/endpoints/health.py

@@ -0,0 +1,29 @@
+from fastapi import APIRouter, Depends, status
+from sqlalchemy.orm import Session
+from app.core.database import get_db
+
+router = APIRouter()
+
+@router.get("/health", status_code=status.HTTP_200_OK, tags=["Health"])
+def health_check(db: Session = Depends(get_db)):
+    """
+    Check the health of the API.
+    
+    Returns:
+        dict: Status information about the API and its dependencies
+    """
+    # Check database connection
+    try:
+        # Just execute a simple query
+        db.execute("SELECT 1")
+        db_status = "healthy"
+    except Exception as e:
+        db_status = f"unhealthy: {str(e)}"
+    
+    return {
+        "status": "online",
+        "api_version": "1.0",
+        "dependencies": {
+            "database": db_status
+        }
+    }

app/api/endpoints/items.py

@@ -0,0 +1,79 @@
+from typing import List, Optional
+from fastapi import APIRouter, Depends, HTTPException, status, Query
+from sqlalchemy.orm import Session
+
+from app.core.database import get_db
+from app.models.item import Item
+from app.schemas.item import Item as ItemSchema, ItemCreate, ItemUpdate
+
+router = APIRouter()
+
+@router.post("/items/", response_model=ItemSchema, status_code=status.HTTP_201_CREATED, tags=["Items"])
+def create_item(item: ItemCreate, db: Session = Depends(get_db)):
+    """
+    Create a new item.
+    """
+    db_item = Item(name=item.name, description=item.description)
+    db.add(db_item)
+    db.commit()
+    db.refresh(db_item)
+    return db_item
+
+@router.get("/items/", response_model=List[ItemSchema], tags=["Items"])
+def read_items(
+    skip: int = 0, 
+    limit: int = 100, 
+    name: Optional[str] = Query(None, description="Filter by name"),
+    db: Session = Depends(get_db)
+):
+    """
+    Retrieve items with optional filtering.
+    """
+    query = db.query(Item)
+    
+    if name:
+        query = query.filter(Item.name.contains(name))
+        
+    items = query.offset(skip).limit(limit).all()
+    return items
+
+@router.get("/items/{item_id}", response_model=ItemSchema, tags=["Items"])
+def read_item(item_id: int, db: Session = Depends(get_db)):
+    """
+    Get a specific item by ID.
+    """
+    item = db.query(Item).filter(Item.id == item_id).first()
+    if item is None:
+        raise HTTPException(status_code=404, detail="Item not found")
+    return item
+
+@router.put("/items/{item_id}", response_model=ItemSchema, tags=["Items"])
+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.add(db_item)
+    db.commit()
+    db.refresh(db_item)
+    return db_item
+
+@router.delete("/items/{item_id}", status_code=status.HTTP_204_NO_CONTENT, tags=["Items"])
+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/core/app.py

@@ -0,0 +1,27 @@
+from fastapi import FastAPI
+from fastapi.middleware.cors import CORSMiddleware
+
+from app.core.config import settings
+from app.api.endpoints import health, api_router
+
+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=["*"],
+)
+
+# Include routers
+app.include_router(health.router)
+app.include_router(api_router, prefix=settings.API_V1_STR)

app/core/config.py

@@ -0,0 +1,26 @@
+from typing import List
+from pathlib import Path
+from pydantic_settings import BaseSettings
+
+class Settings(BaseSettings):
+    # Base settings
+    PROJECT_NAME: str = "FastAPI Endpoint Service"
+    PROJECT_DESCRIPTION: str = "A fast endpoint service built with FastAPI"
+    VERSION: str = "0.1.0"
+    API_V1_STR: str = "/api/v1"
+    SECRET_KEY: str = "change-this-in-production"
+    DEBUG: bool = True
+    
+    # CORS settings
+    CORS_ORIGINS: List[str] = ["*"]
+    
+    # Database
+    DB_DIR = Path("/app") / "storage" / "db"
+    DB_DIR.mkdir(parents=True, exist_ok=True)
+    SQLALCHEMY_DATABASE_URL: str = f"sqlite:///{DB_DIR}/db.sqlite"
+    SQLALCHEMY_POOL_RECYCLE: int = 3600
+    
+    class Config:
+        env_file = ".env"
+        
+settings = Settings()

app/core/database.py

@@ -0,0 +1,29 @@
+from sqlalchemy import create_engine
+from sqlalchemy.ext.declarative import declarative_base
+from sqlalchemy.orm import sessionmaker
+from pathlib import Path
+
+from app.core.config import settings
+
+# Ensure the DB directory exists
+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)
+
+Base = declarative_base()
+
+# Dependency to get DB session
+def get_db():
+    db = SessionLocal()
+    try:
+        yield db
+    finally:
+        db.close()

app/models/__init__.py

@@ -0,0 +1,2 @@
+# Import your models here for Alembic to detect
+from app.models.item import Item

app/models/base.py

@@ -0,0 +1,11 @@
+from datetime import datetime
+from sqlalchemy import Column, Integer, DateTime
+from app.core.database import Base
+
+class TimestampModel(Base):
+    """Base model with created and updated timestamps."""
+    __abstract__ = True
+    
+    id = Column(Integer, primary_key=True, index=True)
+    created_at = Column(DateTime, default=datetime.utcnow, nullable=False)
+    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow, nullable=False)

app/models/item.py

@@ -0,0 +1,9 @@
+from sqlalchemy import Column, String, Text
+from app.models.base import TimestampModel
+
+class Item(TimestampModel):
+    """Item model for demonstration purposes."""
+    __tablename__ = "items"
+    
+    name = Column(String(255), nullable=False, index=True)
+    description = Column(Text, nullable=True)

app/schemas/__init__.py

@@ -0,0 +1 @@
+# Import your schemas here for easy access

app/schemas/item.py

@@ -0,0 +1,30 @@
+from typing import Optional
+from datetime import datetime
+from pydantic import BaseModel
+
+class ItemBase(BaseModel):
+    """Base schema for Item model."""
+    name: str
+    description: Optional[str] = None
+    
+class ItemCreate(ItemBase):
+    """Schema for creating a new Item."""
+    pass
+    
+class ItemUpdate(ItemBase):
+    """Schema for updating an existing Item."""
+    name: Optional[str] = None
+    
+class ItemInDBBase(ItemBase):
+    """Base schema for Item with DB fields."""
+    id: int
+    created_at: datetime
+    updated_at: datetime
+    
+    class Config:
+        """Configure Pydantic to read data from an ORM model."""
+        from_attributes = True
+        
+class Item(ItemInDBBase):
+    """Schema for retrieving Item data."""
+    pass

main.py

@@ -0,0 +1,11 @@
+from app.core.config import settings
+import uvicorn
+from app.core.app import app
+
+if __name__ == "__main__":
+    uvicorn.run(
+        "app.core.app:app", 
+        host="0.0.0.0", 
+        port=8000, 
+        reload=settings.DEBUG
+    )

requirements.txt

@@ -0,0 +1,7 @@
+fastapi>=0.105.0,<0.106.0
+uvicorn>=0.24.0,<0.25.0
+sqlalchemy>=2.0.0,<3.0.0
+pydantic>=2.5.0,<3.0.0
+pydantic-settings>=2.1.0,<3.0.0
+alembic>=1.13.0,<2.0.0
+python-dotenv>=1.0.0,<2.0.0