Files
Motionity/PACKAGING.md
T
kawaandClaude Opus 5 271107203d build: update electron to 43 and keep node_modules out of the asar
Electron 40 is affected by GHSA-9f4c-93c8-jc8g (CVSS 7.2): a sandboxed iframe
can bypass the allow-popups restriction through the OpenURL navigation path.
Motionity renders no iframes, so the practical exposure was near zero, but
Electron only patches its latest three majors — on 40 there would be no fix for
the next advisory either. npm audit now reports zero vulnerabilities.

electron/main.js needed no changes: it uses only APIs stable across 40 to 43.

While verifying the packaged output, the asar turned out to carry @ffmpeg's
transitive dependencies (node-fetch, whatwg-url, regenerator-runtime and
friends). The app loads the vendored UMD bundle from src/vendor/ffmpeg/ and
requires nothing outside electron and node builtins, so build.files now excludes
node_modules wholesale instead of naming @ffmpeg — the same result without
having to track a dependency tree that is not ours.

Verified: electron-builder 26.15.3 packages electron 43.4.0, and the asar
contains the five vendored ffmpeg files and zero node_modules entries.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-08-12 15:49:55 +02:00

8.5 KiB

Packaging Motionity

Three distribution targets share one source tree (src/, a plain static app):

Target Output Build host
Desktop Motionity Setup 1.0.0.exe, Motionity-1.0.0-x64.AppImage, .flatpak Windows for .exe, Linux (or WSL2) for AppImage/Flatpak
Container motionity:latest, ~86 MB on disk / ~57 MB pulled any Docker host
Bare metal src/ behind Node, nginx or Caddy any

0. One prerequisite for every target: vendor the assets

npm install          # now required for every target, not just the desktop ones
npm run vendor       # ~24 MB, writes src/vendor/ (gitignored)

index.html used to pull jQuery, fabric.js, lottie, pickr, selection-js, the WebFont loader and Inter from five different CDNs. scripts/vendor.mjs downloads all of them into src/vendor/ and the app now references only those local copies. Without this step the page loads but every script tag 404s.

ffmpeg.wasm is handled differently: vendor.mjs copies it out of node_modules instead of downloading it, which is why npm install is now a prerequisite everywhere. package-lock.json pins those packages by integrity hash, so the bytes that reach the image are the bytes npm verified. The asm.js build this replaced was fetched from a public archive.org mirror with no integrity check of any kind — a changed object there would have executed in the page unnoticed.

Two consequences worth knowing:

  • @ffmpeg/core-st is the single-threaded core, chosen deliberately. The default @ffmpeg/core is built with pthreads and needs SharedArrayBuffer, which requires COOP/COEP cross-origin isolation, which would break the Pixabay, Unsplash and Google Fonts requests the editor makes.
  • The two @ffmpeg/* packages are dependencies, not devDependencies, so the Docker vendor stage can npm ci --omit=dev without pulling in electron. That makes electron-builder want to bundle them into the asar too, so build.files excludes node_modules/** outright — the packaged app requires nothing but electron and node builtins, and the copies it loads live in src/vendor/ffmpeg/.

The Docker build runs npm ci and the vendor step inside the image, so it is the one target where you can skip both locally.

1. Desktop — Electron

electron/main.js starts the same static server the bare-metal target uses, on 127.0.0.1 with a random port, and points the window at it.

This is deliberate, do not "simplify" it to loadFile(). Chromium exposes WebCodecs (VideoEncoder, the fast exporter in src/js/render.js) and IndexedDB (project storage via localbase) only in a secure context. file:// is not one; a loopback HTTP origin is. Load the app from file:// and export silently falls back to real-time MediaRecorder capture and projects stop saving.

npm run dev            # run the desktop app from source

npm run dist:win       # NSIS installer + portable .exe -> dist/
npm run dist:appimage  # .AppImage -> dist/
npm run dist:flatpak   # .flatpak  -> dist/
npm run dist:linux     # both Linux targets

Each dist:* script re-runs vendor and regenerates build/icon.png (scripts/make-icon.cjs rasterises the logo geometry with zlib only — no ImageMagick, no sharp).

If the NSIS step fails with "Access denied" on Motionity.exe

On a locked-down Windows machine the security agent can take an exclusive lock on the freshly written 214 MB unsigned dist/win-unpacked/Motionity.exe, and the 7-Zip step that builds the installer payload then cannot read it. The symptom is a build that produces dist/win-unpacked/ correctly and dies right after "Archive size":

.\Motionity.exe : Accès refusé.
WARNING: Cannot open 2 files

The ACL is intact (the owner still has FullControl), so this is a filter driver, not a permissions problem. Fixes, in order of preference:

  1. Exclude the repository's dist/ directory in the endpoint protection agent.
  2. Build on a machine or CI runner without that agent.
  3. Ship dist/win-unpacked/electron-builder --win dir is unaffected.

Running npm run dev from a VS Code terminal

VS Code exports ELECTRON_RUN_AS_NODE=1, which turns the electron binary into plain Node and leaves the electron module empty. main.js detects this and prints a message. Fix it in the shell:

env -u ELECTRON_RUN_AS_NODE npm run dev     # bash
$env:ELECTRON_RUN_AS_NODE=$null; npm run dev  # PowerShell

Is WSL enough for AppImage and Flatpak?

AppImage: yes. electron-builder produces the squashfs itself, so no FUSE is needed at build time. To run the result inside WSL you need libfuse2 (or ./Motionity-1.0.0-x64.AppImage --appimage-extract-and-run), and WSLg on Windows 11 gives you the GUI.

Flatpak: technically yes, practically annoying. flatpak-builder runs under WSL2 (the kernel has the user namespaces and /dev/fuse that bubblewrap needs), but you must install the runtimes by hand first and there is no xdg-desktop-portal to fall back on. If it fights you, build it in a Linux container instead — it is the same command with fewer moving parts.

.exe: no. Build it on the Windows side. Cross-building NSIS from Linux needs Wine and rules out signing.

This machine currently has no WSL distro other than docker-desktop, so the Linux targets have not been run here. Setup, from PowerShell:

wsl --install -d Ubuntu

Then inside Ubuntu:

sudo apt update
sudo apt install -y nodejs npm libfuse2            # AppImage
sudo apt install -y flatpak flatpak-builder elfutils  # Flatpak
flatpak remote-add --if-not-exists --user flathub \
  https://dl.flathub.org/repo/flathub.flatpakrepo
flatpak install --user -y flathub \
  org.freedesktop.Platform//23.08 \
  org.freedesktop.Sdk//23.08 \
  org.electronjs.Electron2.BaseApp//23.08

cd /mnt/c/Users/<you>/git\ azuze/motionity-2
npm install
npm run dist:linux

Note that building on /mnt/c is slow. Copying the tree into the WSL filesystem (~/motionity) is several times faster.

2. Docker

docker build -t motionity:latest .
docker run --rm -p 8080:8080 motionity:latest
# or: docker compose up --build

The runtime image is static-web-server (Rust) on Alpine — 9 MB of base image, no Node, no shell tooling, running as UID 65534. Everything above that is the app itself: 46 MB of bundled stock media plus 20 MB of vendored libraries.

Two knobs if the size matters more than offline completeness:

# -23 MB: MP4/GIF export reports itself unavailable (WEBM export is unaffected).
# There is no runtime download to fall back on any more, by design.
docker build --build-arg WITH_FFMPEG=0 -t motionity:slim .

# -33 MB: drop the bundled royalty-free music library (removes the Audio panel
# presets; uploads still work). Add to .dockerignore:
#   src/assets/audio

3. Bare metal

npm run vendor
npm start                       # http://127.0.0.1:8080
HOST=0.0.0.0 PORT=3000 npm start

scripts/server.cjs is dependency-free: correct MIME types, byte ranges (the audio and video panels seek), no directory listings, path-traversal guard. Node 18+.

For a real install, deploy/ has a systemd unit plus nginx and Caddy configs that serve src/ directly, no Node process involved:

sudo cp -r . /opt/motionity
sudo cp deploy/motionity.service /etc/systemd/system/
sudo systemctl enable --now motionity

The secure-context rule, once more

Both the container and the bare-metal targets serve plain HTTP. That is fine on http://localhost, which browsers treat as secure. It is not fine on a LAN address or a domain: VideoEncoder disappears (export falls back to slow real-time capture) and IndexedDB is blocked (projects stop saving), with no error message beyond a console warning.

Anything beyond localhost needs TLS. deploy/Caddyfile is the shortest path — it obtains the certificate itself.

What still needs the internet

Vendoring makes the editor start and export offline. Three features remain online by design, and degrade quietly rather than breaking:

  1. Google Fonts — the font picker loads families through WebFont.load, and src/js/init.js lists them from the Google Fonts API. Offline, text falls back to a system font. Only Inter (the UI font) is bundled.
  2. Pixabay — the Images, Videos and Audio browsers search Pixabay live.
  3. Unsplash — sample images on the empty-state screen.

MP4 and GIF export used to be a fourth: the encoder came from archive.org at conversion time. It is now vendored, so export works fully offline.