Lesson 2.11: Publishing to HoloHub

In this lesson, you'll learn how to package your HoloScript compositions for discovery in the HoloHub registry and how to use creator metadata.

Learning Objectives

• Use the @author, @license, and @version metadata traits.
• Structure your .holo files for registry discovery.
• Understand the HoloHub ingestion process.
• Create a Creator Portfolio entry.

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Metadata Traits

To ensure your work is properly attributed and searchable, use the standard metadata traits at the top of your composition.

composition "Cyberpunk City" {
    @author("CreativeBuilder")
    @license("MIT")
    @version("1.0.0")
    @tags(["neon", "urban", "dynamic-lighting"])

    environment {
        // ...
    }
}

Supported Metadata

Trait	Value	Description
@author	string	Your unique HoloHub username.
@license	string	The license for your scene (e.g., MIT, CC-BY-4.0).
@version	string	Semantic versioning for your composition.
@tags	array	Keywords used for semantic search.

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The Registry Ingest Flow

When you publish a file to the HoloHub registry (via the CLI or Web Portal), the following happens:

1. Validation: The HoloCompositionParser checks for syntax errors.
2. Trait Extraction: The TraitRegistryService indexes all traits used in your scene.
3. Metadata Mapping: Your @author tag is linked to your Creator Portfolio.
4. Preview Generation: A thumbnail is generated using the BrowserRuntime.

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Project: Creating Your Portfolio Scene

Every creator is encouraged to have a "Portfolio Scene"—a .holo file that showcases their best work.

Step 1: Create portfolio.holo

composition "CreativeBuilder Portfolio" {
    @author("CreativeBuilder")
    @tags(["portfolio", "showcase"])

    // Add a signature object
    object "Signature" {
        @interaction
        geometry: "models/logo.glb"
        onInteraction: {
            emit "ui_overlay" "Welcome to my spatial portfolio!"
        }
    }

    // Reference your other scenes
    import_asset "NexusCity_v1" from "holohub://NexusCity"
}

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Best Practices for Visibility

1. Descriptive Names: Use names like AncientRuins_v2 instead of TestScene1.
2. Rich Tags: Use at least 3-5 tags representing the theme and technical features (e.g., @physics, @light-map).
3. README: Always include a README in your project folder to help the HoloHub search engine find you.

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Summary

In this lesson, you learned:

• How to add attribution via metadata traits.
• The requirements for HoloHub discovery.
• How your work is linked to the HoloHub ecosystem.

🎉 Level 2 Conclusion

You have finished the Intermediate track! You are now prepared to build, optimize, and publish complex spatial environments.

Stay tuned for Level 3 (Advanced), where we dive into Custom Shaders and Proximity Federation.

Next Lesson

In Lesson 2.12: Spatial Discovery & Sub-Orbs, you'll learn portals, hologram previews, and nested composition loading.

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Estimated time: 30 minutes Difficulty: ⭐⭐ Intermediate