pydicom-migrasi-clarity/api-app

DICOM Migration REST API

This REST API provides an endpoint to trigger DICOM study migration for a specific Accession Number.

Features

• Migrate DICOM studies by Accession Number
• Token-based authentication
• Detailed JSON responses with operation status
• Proper logging and error handling
• Automatic cleanup of DICOM files after each request

Requirements

• Python 3.9 or higher
• FastAPI
• Uvicorn
• Dependencies from the main DICOM migration project

Installation

1. Install the required dependencies:

cd api-app
pip install -r requirements.txt

Configuration

The API uses the same configuration settings as the main DICOM migration project.

Authentication

The API uses token-based authentication. Set your token using the environment variable:

export API_TOKEN=your-secure-token

If no token is provided, a default token will be used (not recommended for production).

Usage

Starting the API Server

# Start the server on default port 8000
python run.py

# Specify a custom port
python run.py --port 9000

# Specify a custom token
python run.py --token your-secure-token

# Enable auto-reload for development
python run.py --reload

API Endpoints

1. Migrate Study by Accession Number

POST /migrate/{accession_number}

Authentication:

• Bearer token in Authorization header

Response:

Successful migration:

{
  "success": true,
  "message": "Successfully migrated study for accession number: ABC12345",
  "details": {
    "study_uid": "1.2.826.0.1.3680043.9.7307.1.123456",
    "his_integration_success": true
  }
}

Failed migration:

{
  "success": false,
  "message": "Failed to process study: Study not found",
  "details": null
}

Example API Calls

Using curl

# Migrate a study by accession number
curl -X POST "http://localhost:8000/migrate/ABC12345" \
  -H "Authorization: Bearer your-token" \
  -H "Content-Type: application/json"

Using Python requests

import requests

url = "http://localhost:8000/migrate/ABC12345"
headers = {
    "Authorization": "Bearer your-token",
    "Content-Type": "application/json"
}

response = requests.post(url, headers=headers)
print(response.json())

Logs

The API logs are stored in the logs/api.log file. The log includes information about:

• API startup and shutdown
• Migration requests
• Errors during migration process
• Integration with HIS results

Troubleshooting

1. Authentication Error:

   • Make sure you're providing the correct token in the Authorization header
   • Check that the token format is Bearer your-token

2. Study Not Found:

   • Verify that the accession number is correct
   • Check if the PACS server is reachable
   • Verify that the study exists in the source PACS

3. Connection Error:

   • Check PACS connectivity
   • Verify network settings in config/settings.py

Integrating with External Systems

You can call this API from other systems to trigger DICOM migrations for specific studies:

1. Obtain the API token
2. Make a POST request to /migrate/{accession_number}
3. Handle the JSON response based on the success field

Technical Details

DICOM File Cleanup

The API implements a robust cleanup mechanism to ensure that DICOM files are always removed after processing:

1. Exit Handlers: The application registers cleanup handlers via Python's atexit module and signal handlers for graceful cleanup during server shutdown.

2. Per-Request Cleanup: After each migration request completes (whether successful or not), the API explicitly calls the cleanup function to remove all DICOM files associated with the study.

3. Directory Registration: All temporary directories created during the migration process are registered for cleanup, ensuring no files are left behind.

This dual approach (exit handlers + explicit cleanup) ensures that:

• DICOM files are immediately removed after each API request completes
• No files are left behind even if the server crashes or is terminated abnormally
• Disk space is efficiently managed during high-volume operations

Authentication

The API uses Bearer token authentication. The token is specified through: