PdfCraft integration for Nextcloud

Edit the PDFs in your Nextcloud with PdfCraft (formerly PrintCraft), the open-source, Rust-native PDF workbench, without leaving the browser.

• Edit in PdfCraft appears in the Files action menu of every PDF you can read.
• Save (Ctrl/⌘+S) writes the PDF back to Nextcloud, which keeps the previous state as a file version.
• Save As asks for a name and folder and stores a copy.
• Read-only files (for example a share without edit rights) open normally; saving offers a copy.
• If someone else changes the file while you have it open, saving asks whether to replace their version or save a copy instead of overwriting it silently.
• Optionally, clicking a PDF in Files opens it in PdfCraft instead of the viewer: tick Open PDFs here from Files in the editor's top bar.

PdfCraft runs entirely in your browser as WebAssembly. Documents go only between your browser and your Nextcloud, and the server needs no extra software or services.

Requirements

• Nextcloud 33, 34 or 35
• A browser with WebGL2 (any current Chrome, Edge, Firefox or Safari)
• The web server must serve .wasm files as application/wasm. Nextcloud's own .htaccess does this on Apache; the recommended nginx configuration does too (application/wasm wasm; in its types block and wasm in the static-file location).
• Recommended: gzip or Brotli for application/wasm (Debian/Ubuntu Apache's mod_deflate does it out of the box; on nginx add it to gzip_types). PdfCraft is a 33 MB download uncompressed and about 13 MB compressed, fetched once and then cached.

Install

Until the app is in the Nextcloud App Store, the latest version is in CyberFox-81/nextcloud_plugins, whose README has step-by-step commands for Docker, Nextcloud AIO and regular servers. In short:

1. Download integration_pdfcraft.tar.gz and extract it into your Nextcloud's custom_apps/ (or apps/) folder, so you have custom_apps/integration_pdfcraft/appinfo/info.xml.
2. Make it readable by the web server user, e.g. chown -R www-data:www-data custom_apps/integration_pdfcraft.
3. Enable it: sudo -u www-data php occ app:enable integration_pdfcraft. In Docker: docker exec -u www-data nextcloud php occ app:enable integration_pdfcraft.

Once it's in the App Store: Apps ▸ Integration ▸ PdfCraft integration ▸ Download and enable, or sudo -u www-data php occ app:install integration_pdfcraft.

To make PdfCraft the click-to-open default for every user who hasn't chosen otherwise:

sudo -u www-data php occ config:app:set integration_pdfcraft open_by_default --value=true --type=boolean

How it works

Files ── "Edit in PdfCraft" ──▶ /apps/integration_pdfcraft/edit/{fileId}   (src/editor.ts)
                                  │  WebDAV GET/PUT with the user's session
                                  ▼
                                <iframe> /apps/integration_pdfcraft/frame?host=parent   (templates/frame.php)
                                  │  PdfCraft (web/*.wasm) — postMessage bridge

The editor page downloads the PDF over WebDAV and passes it to PdfCraft with postMessage. When you save, PdfCraft passes the bytes back and the page uploads them with If-Match, so a newer version on the server is never overwritten without asking. The frame page is the only one whose Content Security Policy allows compiling WebAssembly.

PdfCraft has an opt-in embedding bridge (?host=parent) since storytold/pdfcraft#842, contributed for this app: a same-origin parent page can open files in PdfCraft and receive its saves. The protocol is described in web/README.md. It is in PdfCraft's main branch, but not yet in a release (the latest is 0.4.0).

patches/pdfcraft-nextcloud.patch adds only an unbranded build feature that leaves out the ArtCraft logos. PdfCraft's code is MIT/Apache, but its brand terms (docs/brand/LICENSE-brand.txt upstream) don't allow modified builds to carry the ArtCraft marks, so the build bundled here leaves them out.

Build from source

make js      # npm ci && vite build → js/
make wasm    # clone PdfCraft, apply the patch, build → web/   (needs Rust, see below)
make dist    # → build/dist/integration_pdfcraft-<version>.tar.gz

make wasm runs scripts/build-pdfcraft-web.sh, which needs the wasm32-unknown-unknown Rust target, wasm-bindgen-cli at the version in PdfCraft's Cargo.lock (0.2.129 at the pinned commit), and optionally wasm-opt from binaryen. Set PDFCRAFT_REF to build another PdfCraft commit, FAST=1 for quicker development builds, and CRAFT_FONTS_DIR to a clone of storytold/craft-fonts to embed PdfCraft's Japanese fonts as its official builds do.

For development, npm run watch rebuilds the scripts as you edit; symlink or copy the repository into custom_apps/integration_pdfcraft of a test server.

Releasing to the App Store

One-time setup (see the App Store developer guide):

1. Create the app's key and certificate request, and keep the key private and backed up:

   mkdir -p ~/.nextcloud/certificates && cd ~/.nextcloud/certificates
   openssl req -nodes -newkey rsa:4096 -keyout integration_pdfcraft.key -out integration_pdfcraft.csr -subj "/CN=integration_pdfcraft"

2. Submit integration_pdfcraft.csr as integration_pdfcraft/integration_pdfcraft.csr in a pull request to nextcloud/app-certificate-requests. Save the signed certificate they reply with as ~/.nextcloud/certificates/integration_pdfcraft.crt.
3. Register the app at apps.nextcloud.com/developer/apps/new with the certificate and this signature:

   echo -n "integration_pdfcraft" | openssl dgst -sha512 -sign ~/.nextcloud/certificates/integration_pdfcraft.key | openssl base64

Each release:

make js && make wasm
scripts/sign-release.sh --key ~/.nextcloud/certificates/integration_pdfcraft.key \
  --cert ~/.nextcloud/certificates/integration_pdfcraft.crt --docker nextcloud

The script code-signs the app with occ integrity:sign-app (borrowed from a running Nextcloud container, or --occ for a local install), packs build/dist/integration_pdfcraft-<version>.tar.gz and prints the App Store signature. Attach the archive to a GitHub release, then submit its download URL and the signature at apps.nextcloud.com/developer/apps/releases/new.

Every new version also goes to nextcloud_plugins, replacing the previous one, with that repository's script (from a clone next to this one):

../nextcloud_plugins/scripts/update-plugin.py build/dist/integration_pdfcraft-<version>.tar.gz

Limitations

• PdfCraft is young. Annotating, forms, signing, organizing pages and redaction work well; reliably editing existing text is still limited upstream.
• One person edits at a time. There is no live co-editing; concurrent saves are caught and you choose what happens.
• Files locked by another app (for example while open in Collabora) can't be saved until the lock is released; save a copy instead.
• The whole PDF is held in the browser, so very large files need a correspondingly capable device.

License

This app is licensed under the AGPL-3.0-or-later. PdfCraft, bundled in web/, is licensed under MIT OR Apache-2.0; its bundled fonts and assets carry their own open licenses (see PdfCraft's ATTRIBUTION.md). "PdfCraft" refers to the upstream project; this integration is not affiliated with it.