In this document we cover the core 3rd party dependencies we have in UCloud and assess risk based on the following factors:

  • How essential is the dependency for UCloud?

    • Scale: 1 (low) - 5 (high)

  • How essential is knowledge of the system to develop UCloud (while keeping it stable and secure)?

    • Scale: 1 (low) - 5 (high)

    • The assessment will include if the knowledge is only essential for a single component or system-wide

  • Difficulty of migrating to an alternative technology

    • Scale: 1 (low) - 5 (high)

  • Likelihood of the dependency getting discontinued in the coming 5 years

    • Scale: 1 (low) - 5 (high)

We consider a 3rd party dependency to be anything not created by the SDU eScience Center, examples include:

  • Software library

  • Tool

  • Hosted software (e.g. a database server)

  • Technical specifications

We use the following format:

### Dependency name

- __Website:__ https://example.com
- __Short description:__ Lorem ipsum dolor sit amet, consectetur adipisicing elit.
- __Described in:__ [Article 1](#), [Article 2](#), [Article 3](#)

__Assessment:__

- __How essential is the dependency for UCloud?__ 1 (low) - 5 (high)
- __How essential is knowledge of the system to develop UCloud?__ 1 (low) - 5 (high)
- __Difficulty of migrating to an alternative technology:__ 1 (low) - 5 (high)
- __Alternative technologies:__ (If relevant) We could use ...
- __Likelihood of the dependency getting discontinued in the coming 5 years:__ 1 (low) - 5 (high)

Notes and explanation go here

Backend

Kotlin

  • Website: https://kotlinlang.org/

  • Short description: The Kotlin programming language is a modern programming language which runs on various platforms, including the JVM. In UCloud we run the JVM variant. All micro-services of UCloud are written in Kotlin.

  • Described in: Indirectly in the following documents: Structure of a micro-service, Getting started

Assessment:

  • How essential is the dependency for UCloud? 5

  • How essential is knowledge of the system to develop UCloud? 5

  • Difficulty of migrating to an alternative technology: 5

  • Likelihood of the dependency getting discontinued in the coming 5 years: 1

kotlinx.coroutines

Assessment:

  • How essential is the dependency for UCloud? 5

  • How essential is knowledge of the system to develop UCloud? 4 (system-wide)

  • Difficulty of migrating to an alternative technology: 4

  • Likelihood of the dependency getting discontinued in the coming 5 years: 1

kotlinx.coroutines is listed as an official JetBrains product making it roughly as reliable as the Kotlin programming language itself.

Ktor

Assessment:

  • How essential is the dependency for UCloud? 4

  • How essential is knowledge of the system to develop UCloud? 2 (system-wide)

  • Difficulty of migrating to an alternative technology: 2

  • Alternative technologies: Both client and server could be replaced by another lightweight alternative

  • Likelihood of the dependency getting discontinued in the coming 5 years: 1

Ktor is listed as an official JetBrains product making it roughly as reliable as the Kotlin programming language itself.

Migration is a fairly straight-forward process since most of the code is wrapped by UCloud code. Business logic would most likely not be significantly affected by the migration.

HTTP and WebSockets

Assessment:

  • How essential is the dependency for UCloud? 5

  • How essential is knowledge of the system to develop UCloud? 5 (system-wide)

  • Difficulty of migrating to an alternative technology: 5

  • Likelihood of the dependency getting discontinued in the coming 5 years: 1

Kubernetes

  • Website: https://kubernetes.io/

  • Short description: Container orchestration. This is used both for the deployment of UCloud and scheduling of user jobs.

  • Described in: app-kubernetes

Assessment:

  • How essential is the dependency for UCloud? 4

  • How essential is knowledge of the system to develop UCloud? 4 (few components), 2 (rest of system)

  • Difficulty of migrating to an alternative technology: 3

  • Alternative technologies: Nomad. Bare-metal deployment and compute on different platform (e.g. slurm).

  • Likelihood of the dependency getting discontinued in the coming 5 years: 2

Note that our current Kubernetes deployment uses K3s. See infrastructure documentation for more details.

Docker

Assessment:

  • How essential is the dependency for UCloud? 3

  • How essential is knowledge of the system to develop UCloud? 2 (system-wide)

  • Difficulty of migrating to an alternative technology: 3

  • Likelihood of the dependency getting discontinued in the coming 5 years: 2

Docker is natively supported by all large cloud providers, including AWS and Azure. Docker is unlikely to be discontinued without an alternative in place.

PostgreSQL

Assessment:

  • How essential is the dependency for UCloud? 5

  • How essential is knowledge of the system to develop UCloud? 5 (system-wide)

  • Difficulty of migrating to an alternative technology: 3

  • Alternative technologies: A different SQL database.

  • Likelihood of the dependency getting discontinued in the coming 5 years: 1

PostgreSQL has had active development since 1986 with many large companies using it in production as well as sponsoring development.

Redis

Assessment:

  • How essential is the dependency for UCloud? 4

  • How essential is knowledge of the system to develop UCloud? 2 (system-wide)

  • Difficulty of migrating to an alternative technology: 3

  • Likelihood of the dependency getting discontinued in the coming 5 years: 1

Redis has been in active development since 2009. According to DB-engines ranking Redis is the most popular key-value database.

Most of the code in UCloud never interfaces directly with Redis. All micro-services of UCloud should instead interface with the abstractions provided by service-lib. This makes significant knowledge of redis mostly irrelevant.

ElasticSearch

Assessment:

  • How essential is the dependency for UCloud? 3

  • How essential is knowledge of the system to develop UCloud? 4 (few component), 1 (rest of system)

  • Difficulty of migrating to an alternative technology: 2

  • Likelihood of the dependency getting discontinued in the coming 5 years: 1

ElasticSearch has been in active development since 2010. According to DB-engines ranking ElasticSearch is the most popular search engine database.

Gradle

Assessment:

  • How essential is the dependency for UCloud? 4

  • How essential is knowledge of the system to develop UCloud? 3

  • Difficulty of migrating to an alternative technology: 4

  • Likelihood of the dependency getting discontinued in the coming 5 years: 1

Gradle is a build tool which is recommended in many parts of the official Kotlin documentation.

Jenkins

Assessment:

  • How essential is the dependency for UCloud? 3

  • How essential is knowledge of the system to develop UCloud? 1

  • Difficulty of migrating to an alternative technology: 2

  • Likelihood of the dependency getting discontinued in the coming 5 years: 1

Frontend

ReactJS

Assessment:

  • How essential is the dependency for UCloud? 5

  • How essential is knowledge of the system to develop UCloud? 5

  • Difficulty of migrating to an alternative technology: 5

  • Likelihood of the dependency getting discontinued in the coming 5 years: 1

Developed by Facebook and used in many different companies and websites.

NPM

Assessment:

  • How essential is the dependency for UCloud? 4

  • How essential is knowledge of the system to develop UCloud? 4

  • Difficulty of migrating to an alternative technology: 3

  • Likelihood of the dependency getting discontinued in the coming 5 years: 2

Vite

  • Website: https://vitejs.dev/

  • Short description: Tooling + module bundler for JavaScript applications.

Assessment:

  • How essential is the dependency for UCloud? 4

  • How essential is knowledge of the system to develop UCloud? 3

  • Difficulty of migrating to an alternative technology: 3

  • Likelihood of the dependency getting discontinued in the coming 5 years: 1

TypeScript

Assessment:

  • How essential is the dependency for UCloud? 5

  • How essential is knowledge of the system to develop UCloud? 5

  • Difficulty of migrating to an alternative technology: 5

  • Likelihood of the dependency getting discontinued in the coming 5 years: 1

Redux

Assessment:

  • How essential is the dependency for UCloud? 5

  • How essential is knowledge of the system to develop UCloud? 5

  • Difficulty of migrating to an alternative technology: 3

  • Likelihood of the dependency getting discontinued in the coming 5 years: 2

Redux is a commonly used library for state management in React-based applications. It has more than 3.5 million weekly downloads on NPM.

Tools

IntelliJ IDEA (and other relevant JetBrains IDEs)

Assessment:

  • How essential is the dependency for UCloud? 2

  • How essential is knowledge of the system to develop UCloud? 2

  • Difficulty of migrating to an alternative technology: 1

  • Alternative technologies: Any other text editor. IntelliJ IDEA is not a requirement to develop UCloud.

  • Likelihood of the dependency getting discontinued in the coming 5 years: 1

Developed by JetBrains who has also developed several of our other dependencies.

Git

Assessment:

  • How essential is the dependency for UCloud? 5

  • How essential is knowledge of the system to develop UCloud? 4

  • Difficulty of migrating to an alternative technology: 3

  • Likelihood of the dependency getting discontinued in the coming 5 years: 1

GitHub

Assessment:

  • How essential is the dependency for UCloud? 3

  • How essential is knowledge of the system to develop UCloud? 3

  • Difficulty of migrating to an alternative technology: 3

  • Alternative technologies: Any other hosting platform for Git repositories

  • Likelihood of the dependency getting discontinued in the coming 5 years: 1

ZenHub

  • Website: https://www.zenhub.com/

  • Short description:

  • Described in: Not currently described in the UCloud documentation.

Assessment:

  • How essential is the dependency for UCloud? 4

  • How essential is knowledge of the system to develop UCloud? 5

  • Difficulty of migrating to an alternative technology: 2

  • Alternative technologies: If required, we could fallback to using just the issues in our GitHub issue tracker. ZenHub stores all issues directly in GitHub.

  • Likelihood of the dependency getting discontinued in the coming 5 years: 2