tower-package

Bundle builder for Tower apps. Used by the Tower CLI to pack an app directory into a gzipped tar archive, and published as an npm package (tower-package-wasm) for building bundles from TypeScript.

The crate has three layers:

• Core (always compiled) — pure types and the build_package function that turns in-memory bytes into a deterministic tar.gz.
• Native (native feature, default) — Package::build walks the filesystem, resolves globs, reads files, and delegates to the core. Used by the Tower CLI.
• WASM (wasm feature) — wasm-bindgen wrapper exposing buildBundle to JavaScript.

Native (Rust)

[dependencies]
tower-package = "0.3"   # default features include `native`

Existing CLI callers are unchanged.

WebAssembly (TypeScript)

Build from inside the nix devshell (nix develop):

./scripts/build.sh            # bundler (webpack/vite/rollup) — default
./scripts/build.sh web        # native ES modules, fetch-based init
./scripts/build.sh nodejs     # CommonJS, Node 18+

Output lands in pkg/ and is publishable to npm as tower-package-wasm.

Usage

import { buildPackage, PackageInputs } from 'tower-package-wasm';

const inputs: PackageInputs = {
  appFiles: [
    { archiveName: 'app/main.py', bytes: new TextEncoder().encode('print("hi")') },
  ],
  moduleFiles: [],
  towerfileBytes: new TextEncoder().encode(
    '[app]\nname = "my-app"\nscript = "main.py"\n',
  ),
};

const tarGz: Uint8Array = buildPackage(inputs);

Archive names must already be rooted under app/ or modules/<name>/; the core does no path rewriting. invoke, parameters, and import paths in the manifest are derived from towerfileBytes.

Output is byte-deterministic for a given input: entries are sorted by archiveName, tar headers are normalized (zero mtime/uid/gid, mode 0644), and the gzip header embeds no mtime. The package format (ustar + gzip, MANIFEST + Towerfile at the top level) matches what the Tower CLI produces natively.

Tests

cargo test -p tower-package            # native Rust tests
./scripts/build.sh nodejs              # then
cd test && npm install && npm test     # TypeScript tests