BOM Structure#

Code

PKG.BOM.001

Validator

Not yet implemented

Compatibility

Tags

Summary#

The BOM is a metadata file identified by the name com.nvidia.simready.packaging.bom.json. It MUST list all content files in the package with per-item fields, using forward-slash relative paths with no duplicates.

Description#

Metadata File#

The BOM is a metadata file identified by the name com.nvidia.simready.packaging.bom.json. It follows the standard metadata conventions defined by PKG.META.001 (JSON with UTF-8 encoding, reverse domain naming, format_version, write-once semantics) and is discovered through the standard metadata discovery mechanisms defined by PKG.DEF.001.

Completeness#

The BOM MUST list all content files contained in the package. Content files are all files that are not the package definition file and not metadata files. Folders are implicit and derived from file paths; empty folders cannot be represented (use a placeholder file like .keep if needed).

BOM-Level Fields#

The BOM consists of: format_version (string, MUST — per PKG.META.001), items (array, MUST).

Item-Level Fields#

Each BOM item includes: relative_path (string, MUST), size (integer, MUST), hash (object, SHOULD — required for integrity verification, see PKG.HASH.001).

Path Format#

Relative paths MUST use forward slashes (/) as path separators regardless of the underlying storage system. This applies to the relative_path field.

Uniqueness#

Each relative_path in the BOM MUST be unique within the package. No two BOM items may have the same relative_path value.

Content Hash Authority#

When a BOM is present, its items array defines the authoritative set of content files for content_hash computation (see PKG.HASH.001). Step 1 of the content hash algorithm uses the BOM items instead of enumerating the filesystem, and step 2 uses the sha256 value from each item’s hash object instead of computing it from file bytes. The remaining steps (sort, concatenate, hash) are unchanged.

Why is it required?#

  • A complete content file manifest enables per-file delivery — consumers can fetch only the files they need instead of downloading the entire package

  • A canonical path format prevents platform-specific ambiguity when the same package is consumed on different operating systems

Examples#

// Valid: BOM with two items including hash objects
{
  "format_version": "1.0",
  "items": [
    {
      "relative_path": "meshes/oak_tree.usd",
      "size": 245760,
      "hash": { "sha256": "a1b2c3d4..." }
    },
    {
      "relative_path": "textures/bark_diffuse.png",
      "size": 1048576,
      "hash": {
        "sha256": "e5f60718...",
        "sha256-first1m": "ff00ff00..."
      }
    }
  ]
}

// Invalid: duplicate relative_path
{
  "format_version": "1.0",
  "items": [
    { "relative_path": "meshes/tree.usd", "size": 100 },
    { "relative_path": "meshes/tree.usd", "size": 200 }
  ]
}

// Invalid: backslash path separator
{
  "format_version": "1.0",
  "items": [
    { "relative_path": "meshes\\tree.usd", "size": 100 }
  ]
}

How to comply#

  • Create the BOM as a metadata file named com.nvidia.simready.packaging.bom.json, following PKG.META.001 conventions

  • Include format_version as a required field

  • Include every content file in the package in the BOM items array (exclude the package definition file and metadata files)

  • Include relative_path and size for each item; include hash for integrity verification

  • Use forward slashes exclusively in all path values

  • Ensure each relative_path appears exactly once