t5de-api/docs/pack.md

Product packs (format 1)

A product pack is a folder on the user's machine holding one community product: its manifest, t5de-product.json, and the product's files. T5DE's proxy serves packs to the client as if they were IMVU products. Package pack reads and checks them (pack.Load).

blue-fur-coat/
  t5de-product.json
  product.chkn        the files, zipped (or files/, not both)

Manifest

t5de-product.json, UTF-8 JSON:

{
  "format": 1,
  "id": "blue-fur-coat",
  "revision": 1,
  "name": "Blue Fur Coat",
  "creator": "Some Creator",
  "description": "<p>HTML description</p>",
  "rating": "general"
}

Field	Rules
format	1
id	1-64 of a-z, 0-9 and -, not starting or ending with -. Names the product locally; the hub assigns global IDs later.
revision	an integer, at least 1. Raise it when the files change, so the client doesn't keep the old ones cached.
name	1-64 characters after trimming spaces, no control characters
creator	optional; up to 64 characters, no control characters
description	optional; HTML, up to 20000 bytes. Cleaned by an allowlist (package safehtml) wherever it's shown.
rating	general or adult; must agree with index.xml (below)

Other fields are an error, and so is anything after the object.

Files

The product's files are IMVU's product files, as Create Mode makes them: index.xml (required), meshes (.xmf), materials (.xrf), textures (.png, .jpg), and so on. They come one of two ways:

• product.chkn: a zip file, Create Mode's project format, with the files at its root. Folder entries are ignored; files inside folders are an error.
• files/: a folder with the files at its top level. Subfolders are an error.

Having both is an error. Other files in the pack's folder are ignored.

Rules for each file:

• Names: not empty, no / or \, not . or .., no control characters, Latin-1 characters only (CFL files store names as Latin-1), at most 200 bytes (UTF-8). No two files with the same name.
• _contents.json isn't allowed: it makes the client download a product's files separately, which packs don't support.
• Limits: 512 files, 64 MiB per file, 256 MiB in all (uncompressed; sizes are counted while reading, not taken from the zip's headers).

pack.Checksum hashes the files' names and contents (sha256), so the same files give the same checksum however they're stored or compressed. The proxy uses it to notice changes.

index.xml

IMVU's product template (root element <Template>). T5DE reads only these top-level elements and ignores the rest:

Element	Use
ProductRating	required: GA (general) or AP (adult), matching the manifest's rating
ProductName	the name Create Mode gave it
ProductGender	female, male, ...
ProductTypeID	optional integer
BodyPatternProductId	optional integer
__DATAIMPORT	optional: product://<id>/index.xml, the IMVU product it derives from

A product usually derives from an IMVU parent product (a derivable mesh), as products made in Create Mode do. The client asks IMVU for the parent's whole derivation chain and loads the parents' files from IMVU, and the pack's files on top of them: a pack file with the same name as a parent's replaces it (checked with a texture in client 554.8). So a pack holds only what it changes, and the parents' files never pass through T5DE.

How the proxy serves a pack

The proxy builds the files into a CFL, IMVU's product container (package cfl), uncompressed, files in name order, and serves it at productdata/<local ID>/<revision>, the address the client asks for. The client caches a product's files by that address and file name, so a new revision makes clients load the new files. The proxy picks up changed files within a revision too, but a running client may keep the files it already loaded: raise the revision to be sure.