Add POST payoff endpoint

.gitignore

@@ -1 +1,10 @@
 .aider*
+
+.venv
+
+__pycache__
+*.pyc
+
+.mypy_cache
+
+.env

.vscode/settings.json

@@ -0,0 +1,7 @@
+{
+    "python.testing.pytestArgs": [
+        "tests"
+    ],
+    "python.testing.unittestEnabled": false,
+    "python.testing.pytestEnabled": true
+}

.vscode/tasks.json

@@ -0,0 +1,55 @@
+{
+    // See https://go.microsoft.com/fwlink/?LinkId=733558
+    // for the documentation about the tasks.json format
+    "version": "2.0.0",
+    "tasks": [
+        {
+            "label": "Run Mypy",
+            "type": "shell",
+            "command": "uv run mypy . --no-incremental",
+            "problemMatcher": [
+                "$python"
+            ]
+        },
+        {
+            "label": "Isort Check",
+            "type": "shell",
+            "command": "uv run isort . --check --diff",
+            "problemMatcher": [
+                "$python"
+            ]
+        },
+        {
+            "label": "Isort Fix",
+            "type": "shell",
+            "command": "uv run isort .",
+            "problemMatcher": [
+                "$python"
+            ]
+        },
+        {
+            "label": "AutoPEP8 Check",
+            "type": "shell",
+            "command": "uv run autopep8 app/**/*.py --diff",
+            "problemMatcher": [
+                "$python"
+            ]
+        },
+        {
+            "label": "AutoPEP8 Fix",
+            "type": "shell",
+            "command": "uv run autopep8 app/**/*.py --in-place",
+            "problemMatcher": [
+                "$python"
+            ]
+        },
+        {
+            "label": "Autoflake Fix",
+            "type": "shell",
+            "command": "uv run autoflake -i app/**/*.py",
+            "problemMatcher": [
+                "$python"
+            ]
+        }
+    ]
+}

README.md

@@ -0,0 +1,26 @@
+# Loan Operations API (loapi)
+
+A FastAPI-based loan operations management system.
+
+## Features
+
+- RESTful API for loan operations
+- Automatic API documentation
+- Request/response validation
+- Middleware for logging and error handling
+
+## Development
+
+```bash
+# Install dependencies
+uv sync
+
+# Run the development server
+uv run python main.py
+```
+
+## API Documentation
+
+Once running, visit:
+- Swagger UI: http://localhost:8000/docs
+- ReDoc: http://localhost:8000/redoc

app/config.py

@@ -0,0 +1,34 @@
+
+from pydantic import Field
+from pydantic_settings import BaseSettings
+
+
+class Settings(BaseSettings):
+    env: str = Field(default='DEV', alias="ENV")
+
+    # Server settings
+    host: str = Field(default="0.0.0.0", alias="HOST")
+    port: int = Field(default=8000, alias="PORT")
+    debug: bool = Field(default=False, alias="DEBUG")
+    log_level: str = Field(default="INFO", alias="LOG_LEVEL")
+
+    # Database settings
+    oracle_user: str = Field(alias="ORACLE_USER")
+    oracle_password: str = Field(alias="ORACLE_PASSWORD")
+    oracle_dsn: str = Field(alias="ORACLE_DSN")
+
+    # Sentry settings
+    sentry_dsn: str | None = Field(default=None, alias="SENTRY_DSN")
+
+    # Datadog settings
+    dd_service: str = Field(default="loapi", alias="DD_SERVICE")
+    dd_env: str = Field(default="development", alias="DD_ENV")
+    dd_version: str = Field(default="1.0.0", alias="DD_VERSION")
+
+    model_config = {
+        "env_file": ".env",
+        "case_sensitive": False
+    }
+
+
+settings = Settings()  # type:ignore[call-arg]

app/database.py

@@ -0,0 +1,50 @@
+"""Database configuration and connection management."""
+from typing import Generator
+
+from sqlalchemy import MetaData, create_engine
+from sqlalchemy.ext.asyncio import AsyncSession, async_sessionmaker, create_async_engine
+from sqlalchemy.orm import DeclarativeBase, Session, sessionmaker
+
+from app.config import settings
+
+
+class Base(DeclarativeBase):
+    """Base class for SQLAlchemy models."""
+    metadata = MetaData()
+
+
+# Database URL construction
+DATABASE_URL = f"oracle+oracledb://{settings.oracle_user}:{settings.oracle_password}@{settings.oracle_dsn}"
+
+# Synchronous engine for Oracle
+engine = create_engine(
+    DATABASE_URL,
+    echo=settings.debug,
+    pool_pre_ping=True,
+    pool_recycle=3600,
+)
+
+SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
+
+
+def get_db() -> Generator[Session, None]:
+    """Dependency to get database session."""
+    db = SessionLocal()
+    try:
+        yield db
+    finally:
+        db.close()
+
+
+class DatabaseService:
+    """Database service for health checks and utilities."""
+
+    @staticmethod
+    def health_check() -> bool:
+        """Check database connectivity."""
+        try:
+            with SessionLocal() as db:
+                db.execute("SELECT 1 FROM DUAL")  # type:ignore[call-overload]
+                return True
+        except Exception:
+            return False

app/logging.py

@@ -0,0 +1,42 @@
+"""Logging configuration with structured logging."""
+import logging
+import sys
+
+import structlog
+
+from app.config import settings
+
+
+def configure_logging() -> None:
+    """Configure structured logging."""
+
+    structlog.configure(
+        processors=[
+            structlog.stdlib.filter_by_level,
+            structlog.stdlib.add_logger_name,
+            structlog.stdlib.add_log_level,
+            structlog.stdlib.PositionalArgumentsFormatter(),
+            structlog.processors.TimeStamper(fmt="iso"),
+            structlog.processors.StackInfoRenderer(),
+            structlog.processors.format_exc_info,
+            structlog.processors.UnicodeDecoder(),
+            structlog.processors.JSONRenderer(
+            ) if not settings.debug else structlog.dev.ConsoleRenderer(),
+        ],
+        context_class=dict,
+        logger_factory=structlog.stdlib.LoggerFactory(),
+        wrapper_class=structlog.stdlib.BoundLogger,
+        cache_logger_on_first_use=True,
+    )
+
+    # Configure standard logging
+    logging.basicConfig(
+        format="%(message)s",
+        stream=sys.stdout,
+        level=getattr(logging, settings.log_level.upper()),
+    )
+
+
+def get_logger(name: str) -> structlog.BoundLogger:
+    """Get a configured logger instance."""
+    return structlog.get_logger(name)  # type:ignore[no-any-return]

app/middleware.py

@@ -0,0 +1,36 @@
+from typing import Callable, Any
+
+from fastapi import Request, Response
+from slowapi import Limiter, _rate_limit_exceeded_handler
+from slowapi.errors import RateLimitExceeded
+from slowapi.middleware import SlowAPIMiddleware
+from slowapi.util import get_remote_address
+
+from app.config import settings
+from app.logging import get_logger
+
+logger = get_logger(__name__)
+
+# Rate limiter
+limiter = Limiter(key_func=get_remote_address)
+
+
+async def logging_middleware(request: Request, call_next: Callable[[Request], Any]) -> Any:
+    """Log all requests and responses."""
+    logger.debug(
+        "Request received",
+        method=request.method,
+        url=str(request.url),
+        client_ip=get_remote_address(request)
+    )
+
+    response = await call_next(request)
+
+    logger.debug(
+        "Response sent",
+        status_code=response.status_code,
+        method=request.method,
+        url=str(request.url)
+    )
+
+    return response

app/resources/health.py

@@ -0,0 +1,30 @@
+"""Health check endpoints."""
+from fastapi import APIRouter
+
+from app.database import DatabaseService
+from app.logging import get_logger
+
+router = APIRouter()
+logger = get_logger(__name__)
+
+
+@router.get("/health-check")
+async def health_check() -> dict[str, str]:
+    """Comprehensive health check endpoint."""
+
+    # Check database connectivity
+    try:
+        db_healthy = DatabaseService.health_check()
+    except Exception as e:
+        logger.error("Database health check failed", exc_info=e)
+        db_healthy = False
+
+    status = "healthy" if db_healthy else "unhealthy"
+
+    result = {
+        "status": status,
+        "service": "loapi",
+        "database": "connected" if db_healthy else "disconnected"
+    }
+
+    return result

app/resources/payoff.py

@@ -0,0 +1,73 @@
+"""Pay-off endpoints."""
+from datetime import date
+from decimal import Decimal
+from enum import Enum
+from typing import Optional
+
+from fastapi import APIRouter
+from pydantic import BaseModel, Field, validator
+
+from app.logging import get_logger
+
+router = APIRouter()
+logger = get_logger(__name__)
+
+
+class PayoffStatus(str, Enum):
+    """Enum for payoff status values."""
+    PROCESSED = "processed"
+    PENDING = "pending"
+    FAILED = "failed"
+    CANCELLED = "cancelled"
+
+
+class PayoffRequest(BaseModel):
+    """Request model for loan payoff."""
+    loan_id: str = Field(..., description="Loan identifier", min_length=1, max_length=50)
+    payoff_amount: Decimal = Field(..., description="Payoff amount", gt=0, decimal_places=2)
+    payoff_date: date = Field(..., description="Payoff date")
+    borrower_name: Optional[str] = Field(None, description="Borrower name", max_length=100)
+    payment_method: str = Field(..., description="Payment method", regex="^(check|wire|ach|cash)$")
+    notes: Optional[str] = Field(None, description="Additional notes", max_length=500)
+
+    @validator('payoff_date')
+    def validate_payoff_date(cls, v):
+        """Validate payoff date is not in the future."""
+        from datetime import date
+        if v > date.today():
+            raise ValueError('Payoff date cannot be in the future')
+        return v
+
+
+class PayoffResponse(BaseModel):
+    """Response model for loan payoff."""
+    status: PayoffStatus
+    loan_id: str
+    payoff_amount: Decimal
+    payoff_date: date
+    transaction_id: str
+
+
+@router.post("/payoff", response_model=PayoffResponse)
+async def create_payoff(payoff_request: PayoffRequest) -> PayoffResponse:
+    """Create a loan payoff record."""
+    
+    logger.info(f"Processing payoff for loan {payoff_request.loan_id}")
+    
+    # TODO: Add database logic to process payoff
+    # For now, return a mock response
+    
+    import uuid
+    transaction_id = str(uuid.uuid4())
+    
+    response = PayoffResponse(
+        status=PayoffStatus.PROCESSED,
+        loan_id=payoff_request.loan_id,
+        payoff_amount=payoff_request.payoff_amount,
+        payoff_date=payoff_request.payoff_date,
+        transaction_id=transaction_id
+    )
+    
+    logger.info(f"Payoff processed successfully for loan {payoff_request.loan_id}, transaction {transaction_id}")
+    
+    return response

example.env

@@ -0,0 +1,16 @@
+# Server settings
+HOST=0.0.0.0
+PORT=8000
+DEBUG=true
+LOG_LEVEL=INFO
+
+# Database settings
+ORACLE_USER=your_oracle_user
+ORACLE_PASSWORD=your_oracle_password
+ORACLE_DSN=your_oracle_dsn
+
+# Monitoring
+SENTRY_DSN=
+DD_SERVICE=
+DD_ENV=
+DD_VERSION=

main.py

@@ -1,6 +1,67 @@
-def main():
-    print("Hello from loapi!")
+"""
+Main entry point for the Loan Operations API.
+"""
+import sentry_sdk
+from ddtrace import patch_all
+from fastapi import APIRouter, FastAPI
+from sentry_sdk.integrations.fastapi import FastApiIntegration
 
+from app.config import settings
+from app.logging import configure_logging, get_logger
+from app.middleware import logging_middleware
+from app.resources import health, payoff
+
+
+def create_app() -> FastAPI:
+    """Create and configure the FastAPI application."""
+    
+    # Configure monitoring
+    if settings.sentry_dsn:
+        sentry_sdk.init(
+            dsn=settings.sentry_dsn,
+            integrations=[FastApiIntegration()],
+            traces_sample_rate=1.0,
+            environment=settings.dd_env,
+        )
+    
+    if settings.dd_service:
+        # Configure Datadog tracing
+        patch_all()
+    
+    # Configure logging
+    configure_logging()
+    logger = get_logger(__name__)
+    
+    # Create FastAPI app
+    app = FastAPI(
+        title="Loan Operations API",
+        description="SBA Loan Operations API",
+        version="1.0.0",
+        docs_url="/docs",
+        redoc_url="/redoc",
+    )
+    
+    # Include all endpoint routers
+    app.include_router(health.router, tags=["health"])
+    app.include_router(payoff.router, tags=["payoff"])
+    
+    return app
+
+
+def main() -> None:
+    """Run the application."""
+
+    import uvicorn
+
+    uvicorn.run(
+        app,
+        host=settings.host,
+        port=settings.port,
+        log_level=settings.log_level.lower(),
+        reload=settings.debug,
+    )
+
+app = create_app()
 
 if __name__ == "__main__":
     main()

pyproject.toml

@@ -3,5 +3,63 @@ name = "loapi"
 version = "1.0.0"
 description = "Loan Operations API"
 readme = "README.md"
-requires-python = ">=3.14"
-dependencies = []
+requires-python = ">=3.11"
+dependencies = [
+    "fastapi>=0.104.0",
+    "uvicorn[standard]>=0.24.0",
+    "sqlalchemy>=2.0.0",
+    "oracledb>=1.4.0",
+    "pydantic>=2.5.0",
+    "pydantic-settings>=2.1.0",
+    "slowapi>=0.1.9",
+    "sentry-sdk[fastapi]>=1.38.0",
+    "ddtrace>=2.5.0",
+    "structlog>=23.2.0",
+    "alembic>=1.13.0",
+]
+
+[project.optional-dependencies]
+dev = [
+    "pytest>=7.4.0",
+    "pytest-asyncio>=0.21.0",
+    "pytest-cov>=4.1.0",
+    "mypy>=1.7.0",
+    "pylint>=3.0.0",
+    "autopep8>=2.0.0",
+    "isort>=5.12.0",
+    "types-requests>=2.31.0",
+    "httpx>=0.25.0",
+]
+
+[tool.mypy]
+python_version = "3.14"
+strict = true
+warn_return_any = true
+warn_unused_configs = true
+disallow_untyped_defs = true
+exclude = ["tests"]
+
+[tool.pylint.messages_control]
+max-line-length = 88
+disable = ["C0114", "C0116"]
+
+[tool.isort]
+profile = "black"
+multi_line_output = 3
+line_length = 88
+
+[tool.pytest.ini_options]
+pythonpath = ["."]
+testpaths = ["tests"]
+
+[dependency-groups]
+dev = [
+    "autoflake>=2.3.1",
+    "autopep8>=2.3.2",
+    "httpx>=0.28.1",
+    "isort>=7.0.0",
+    "mypy>=1.19.1",
+    "pylint-pydantic>=0.4.1",
+    "pylint[pydantic]>=4.0.4",
+    "pytest[coverage]>=9.0.2",
+]

tests/test_health.py

@@ -0,0 +1,61 @@
+"""Tests for health check endpoints."""                                                                     
+import pytest                                                                                               
+from fastapi.testclient import TestClient                                                                   
+from unittest.mock import patch                                                                             
+                                                                                                            
+from main import create_app                                                                                 
+                                                                                                            
+                                                                                                            
+class TestHealthCheck:                                                                                      
+    """Test cases for health check endpoint."""                                                             
+                                                                                                            
+    @pytest.fixture                                                                                         
+    def client(self) -> TestClient:                                                                                       
+        """Create test client."""                                                                           
+        app = create_app()                                                                                  
+        return TestClient(app)                                                                              
+                                                                                                            
+    @patch('app.database.DatabaseService.health_check')                                                     
+    def test_health_check_database_connected(self, mock_db_health, client) -> None:                                 
+        """Test health check when database is connected."""                                                 
+        # Mock database as healthy                                                                          
+        mock_db_health.return_value = True                                                                  
+                                                                                                            
+        response = client.get("/health-check")                                                              
+                                                                                                            
+        assert response.status_code == 200                                                                  
+        data = response.json()                                                                              
+        assert data["status"] == "healthy"                                                                  
+        assert data["service"] == "loapi"                                                                   
+        assert data["database"] == "connected"                                                              
+        mock_db_health.assert_called_once()                                                                 
+                                                                                                            
+    @patch('app.database.DatabaseService.health_check')                                                     
+    def test_health_check_database_disconnected(self, mock_db_health, client):                              
+        """Test health check when database is disconnected."""                                              
+        # Mock database as unhealthy                                                                        
+        mock_db_health.return_value = False                                                                 
+                                                                                                            
+        response = client.get("/health-check")                                                              
+                                                                                                            
+        assert response.status_code == 200                                                                  
+        data = response.json()                                                                              
+        assert data["status"] == "unhealthy"                                                                
+        assert data["service"] == "loapi"                                                                   
+        assert data["database"] == "disconnected"                                                           
+        mock_db_health.assert_called_once()                                                                 
+                                                                                                            
+    @patch('app.database.DatabaseService.health_check')                                                     
+    def test_health_check_database_exception(self, mock_db_health, client):                                 
+        """Test health check when database check raises exception."""                                       
+        # Mock database health check to raise exception                                                     
+        mock_db_health.side_effect = Exception("Database connection failed")                                
+                                                                                                            
+        response = client.get("/health-check")                                                              
+                                                                                                            
+        assert response.status_code == 200                                                                  
+        data = response.json()                                                                              
+        assert data["status"] == "unhealthy"                                                                
+        assert data["service"] == "loapi"                                                                   
+        assert data["database"] == "disconnected"                                                           
+        mock_db_health.assert_called_once()