RoundCube Bridge

A Nextcloud app that provides a communication bridge between RoundCube (embedded via the mail_roundcube app) and Nextcloud services.

Features

• Attach files from Nextcloud - Pick files from your Nextcloud storage and attach them to emails
• Save attachments to Nextcloud - Save email attachments directly to your Nextcloud files
• Insert share links - Create and insert public share links into your emails
• Calendar integration - Add calendar invitations (.ics files) directly to your Nextcloud Calendar

Requirements

• Nextcloud 32+
• PHP 8.2+
• mail_roundcube app installed and configured
• NextBridge plugin installed in RoundCube

How It Works

The bridge uses postMessage API to communicate between Nextcloud and the RoundCube iframe:

1. Bridge Client Injection - When RoundCube loads in the iframe, the bridge injects a NextcloudBridge JavaScript object
2. RoundCube Plugin - The NextBridge plugin in RoundCube uses this object to request file operations
3. Nextcloud Handlers - The bridge app handles these requests using Nextcloud's APIs (WebDAV, CalDAV, OCS Sharing)

┌────────────────────────────────────────────────────────────┐
│                    Nextcloud                               │
│  ┌─────────────────────────────────────────────────────┐   │
│  │                mail_roundcube_bridge                │   │
│  │  ┌─────────────┐    postMessage    ┌─────────────┐  │   │
│  │  │  Vue App    │◄──────────────────│ Injected    │  │   │
│  │  │  (Bridge)   │                   │ Client      │  │   │
│  │  └──────┬──────┘                   └──────┬──────┘  │   │
│  └─────────┼────────────────────────────────┼──────────┘   │
│            │                                │              │
│     WebDAV/CalDAV                    ┌──────┴──────┐       │
│     OCS APIs                         │  RoundCube  │       │
│                                      │  (iframe)   │       │
│                                      │  NextBridge │       │
│                                      │   plugin    │       │
│                                      └─────────────┘       │
└────────────────────────────────────────────────────────────┘

API Reference

The injected NextcloudBridge object provides:

// Files
NextcloudBridge.pickFiles({ multiple: true, mimeTypes: ['image/*'] })
NextcloudBridge.saveFile(filename, base64Content, mimeType)
NextcloudBridge.saveFiles([{ filename, content, mimeType }])
NextcloudBridge.createShareLink()

// Calendar
NextcloudBridge.getCalendars()
NextcloudBridge.addToCalendar(calendarUrl, icsContent)

// Utils
NextcloudBridge.blobToBase64(blob)
NextcloudBridge.base64ToBlob(base64, mimeType)

Installation

From App Store (soon)

1. Go to Nextcloud Apps
2. Search for "RoundCube Bridge"
3. Click Install

Manual Installation

cd /path/to/nextcloud/apps
git clone https://github.com/Gecka-Apps/nextcloud-roundcube-bridge mail_roundcube_bridge
cd mail_roundcube_bridge
make build

Then enable the app in Nextcloud settings.

Development

Prerequisites

• Node.js 20+
• npm

Setup

# Install dependencies
npm install

# Development build (with source maps)
make dev

# Production build (minified)
make build

# Watch mode (auto-rebuild on changes)
make watch

Code Quality

# PHP CodeSniffer
make phpcs

# PHP Mess Detector
make phpmd

Available Make Targets

Target	Description
help	Show available targets
build	Build production assets
dev	Build development assets
watch	Build and watch for changes
phpcs	Run PHP CodeSniffer
phpmd	Run PHP Mess Detector
appstore	Create app store package
clean	Remove build artifacts
distclean	Remove build artifacts and dependencies

License

This app is released under the GNU Affero General Public License Version 3.

Authors

• Laurent Dinclaux laurent@gecka.nc - Gecka

Related Projects

• mail_roundcube - Nextcloud app that embeds RoundCube
• NextBridge - RoundCube plugin that uses this bridge

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Built with 🥥 and ☕ by Gecka — Kanaky-New Caledonia 🇳🇨