This repo shows one way to put PlantUML diagrams in Azure DevOps wiki.

It's primarily useful in wikis that are published from Git repositories; standard wikis won't work with this because you won't have access to add files in the same way.

The process is:

• Run npm install to restore all the required Node.js packages.
• Run npm run watch. This starts up index.js which is a filesystem watcher tied to a PlantUML image generator.
• Create PlantUML documents using a .puml extension.
• As .puml files are added, changed, and removed, .png image versions of the diagrams will be created based on those files. Each .png will have the same base filename as the .puml file.
• Include the Markdown to show the image in your wiki page.

If you're in VS Code, there's already a watch task wired up and ready to go. Start that, edit your wiki, and things will just work in the background.

The Diagrams folder shows a simple wiki page with a PlantUML diagram embedded.

Other interesting bits:

• The .plantstyles file is tied into the image generation in index.js - you can change the style for images using that file and images will be properly formatted.
• .editorconfig and .markdownlint.json are wired up to help the wiki markdown stay consistent. These will work with VS Code and the markdownlint extension to help you keep things clean. However, this isn't required for the PlantUML integration.

It's not as automatic as the Mermaid support, but since Mermaid is really slow to update in Azure DevOps and there's no traction on getting PlantUML into Azure DevOps, it gets the job done.

I didn't implement this as a CI build because it would mean the build itself needs to commit the generated images back to the original repo and I didn't want a build doing that. You could make it more complex and store the images in a separate repo, but then the wiki isn't as self-contained. This local-build integration seemed a reasonable compromise.