devices-tech-test

Python technical test for device integration hires

Overview

This repository is the starting point for Big Picture's Device Tech Test.

We have created a basic DICOM SCP that we would like you to extend to store the data and forward to a DICOMWeb endpoint.

Setup

Repo

Start by cloning this repository locally. You will not need to publish your copy on GitHub as we are requesting that you send us a zip or tarball with the git history intact.

Installation

How you install this exactly on your host is up to you, but we recommend:

1. Install Python 3 and virtualenv locally on your computer
2. Create and activate a virtualenv for this project and run pip install -r requirements.txt
3. run python src/dicom_scp.py
4. Open a new console tab, activate the virtualenv and run python test/test_scu.py
5. You should see output from the dicom_scp.py execution: INFO:__main__:Store received for patient Healthy Retina - adult

The Tasks

Before getting started, should you have any questions regarding any of the tasks please email stuart@bigpicturemedical.com.

The existing codebase has a very simple PACS-like endpoint for DICOM data from an SCU. These tasks will require you to store the incoming DICOM data and then forward it to a more modern DICOMWeb server.

1. Save the DICOM File

Save the DICOM file locally to a cache directory with a temporary file with a randomly generated name.

• The folder should be configurable via a file that stores properties
• There should be no risk of files for different scans having conflicting names

2. Extract metadata and store

From the DICOM file, extract metadata including patient ID, Study Instance UID and SOP Instance UID along with the saved filename and timestamp. This can be stored in a persistence store of your choosing eg. CSV file, SQLLite etc. The timestamp should be stored in Coordinated Universal Time (UTC) format.

3. Upload the DICOM to a DICOMWeb URL

Send the DICOM to a configurable DICOM Web URL. This should follow the STOW-RS standard defined at https://www.dicomstandard.org/dicomweb/store-stow-rs/.

We have setup an endpoint for you to upload to at https://dicomweb.shared.bigpicturemedical.com/studies, which follows the STOW-RS standard.

• Note that this may take some time and should be run in a separate thread.
• The persistence store should also record which DICOM files have been sent, failed etc.
• The temporary DICOM file stored must be deleted once it has been sent.

What we're looking for

• Maintainable code split logically into files, classes and methods
• Use of applicable design patterns
• Correct usage of appropriate Python libraries
• Tests as documentation
• Git hygiene

Submission

Once complete, please create a zip file or tarball of your repository with the git history intact. Then please send your solution to stuart@bigpicturemedical.com