WP Nextcloud Bridge

A WordPress plugin that connects your WordPress site directly to Nextcloud via WebDAV. Browse, upload, download, share, and sync files — all without leaving WordPress.

Features

• File Browser — Browse your Nextcloud files from the WordPress admin or any page/post via shortcode [nextcloud]
• Upload from Browser — Drag & drop or click to upload. Large files are automatically chunked (3-step WebDAV chunked upload protocol)
• Download Proxy — Download files through WordPress without exposing Nextcloud credentials
• Public Share Links — Generate Nextcloud public share links with one click, auto-copied to clipboard
• Folder Management — Create and delete folders directly from the browser UI
• Directory Sync — Sync specific WordPress directories to Nextcloud on demand (WP → NC, additive only)
• Shortcode — Embed the file browser anywhere with [nextcloud]
• Diagnostics — Built-in diagnostic page for troubleshooting connection issues

Requirements

• WordPress 5.8+
• PHP 7.4+
• cURL extension enabled
• Nextcloud server with WebDAV access

Installation

1. Download the latest release ZIP file
2. In WordPress admin, go to Plugins → Add New → Upload Plugin
3. Upload the ZIP and activate
4. Go to Settings → Nextcloud Bridge to configure

Configuration

Connection Settings

Paths & Sync

Trusted Domain

If your WordPress server accesses Nextcloud via an internal IP (e.g. 172.x.x.x), you must add it to Nextcloud's trusted_domains in config/config.php:

'trusted_domains' => [
    0 => 'cloud.example.com',
    1 => '172.21.0.1:5050',  // your internal address
],

Usage

Shortcode

Embed the file browser on any page or post:

[nextcloud]
[nextcloud path="Documents"]
[nextcloud path="Photos" upload="true" delete="true"]
[nextcloud upload="false" create_folder="false"]

Note: The shortcode is only visible to users with manage_options capability (administrators).

Admin Pages

• Settings → Nextcloud Bridge — Connection settings, test connection, file browser, manual sync
• Settings → NC Diagnostics — Detailed HTTP request/response debugging

File Browser

• Click folder names to navigate into them
• Use the breadcrumb bar to jump to any parent folder
• ⬆️ Upload button or drag & drop files onto the browser area
• ⬇️ Download files through the proxy (credentials stay server-side)
• 🔗 Generate a public share link (auto-copied to clipboard)
• 🗑️ Delete files or folders (when delete="true")
• 📁+ Create new folders

Large File Upload

Files larger than the PHP chunk size are automatically uploaded using Nextcloud's chunked upload protocol:

1. MKCOL — Create a temporary directory under /uploads/{user}/{uuid}/
2. PUT — Upload each 10 MB chunk sequentially with progress tracking
3. MOVE — Assemble .file into the final destination path

The browser shows a per-file progress bar with percentage and chunk counter.

Directory Sync

Configure directory pairs in the settings page to sync local WordPress directories to Nextcloud:

Sync is additive only — it uploads new or modified files but never deletes remote files. Comparison uses file existence → size → modification time.

Architecture

wp-nextcloud-bridge/
├── wp-nextcloud-bridge.php           # Entry point + PSR-4 autoloader
├── inc/
│   ├── class-nextcloud-client.php    # WebDAV/OCS client (pure I/O, no side-effects)
│   ├── class-nc-settings.php         # WordPress Settings API page
│   ├── class-nc-ajax.php             # AJAX endpoint router (browse/upload/sync/share)
│   ├── class-nc-sync.php             # WP→NC incremental sync engine
│   ├── class-nc-shortcode.php        # [nextcloud] shortcode
│   └── class-nc-diagnostics.php      # Diagnostic test page
├── assets/
│   ├── js/
│   │   ├── admin.js                  # Admin settings page JS
│   │   └── front.js                  # Frontend file browser (vanilla JS, no jQuery)
│   └── css/
│       ├── admin.css                 # Admin styles
│       └── front.css                 # Frontend styles (DM Sans + JetBrains Mono)
└── README.md

Design Principles

• Single responsibility — Each class does one thing. The WebDAV client is pure I/O with no WordPress side-effects.
• WordPress-native HTTP — Uses wp_remote_request() with an http_api_curl filter workaround for WebDAV methods (PROPFIND, MKCOL, etc.) where WordPress's WP_Http_Curl transport silently drops the request body.
• No external dependencies — No Composer, no SDK, no jQuery on the frontend. Just PHP + vanilla JS.
• Namespace isolation — All PHP classes live under the WPNC\ namespace with a simple autoloader.
• Security by default — Every AJAX handler verifies nonce + capability. Download proxy supports HMAC-signed tokens for time-limited public access.

WebDAV Methods Used

Troubleshooting

HTTP 400 on all requests

Most likely a Trusted Domain error. Check Settings → NC Diagnostics → Test 3 — if it shows "Trusted domain error", add your WordPress server's address to Nextcloud's trusted_domains config.

HTTP 401 / 403

Authentication failed. Verify username and password. Using an App Password (Nextcloud → Settings → Security → Devices & sessions) is recommended.

HTTP 404

The WebDAV endpoint was not found. Check that the Nextcloud URL is correct and does not include a trailing slash or path suffix.

Uploads fail for large files

1. Check PHP's upload_max_filesize and post_max_size in php.ini — these limit individual chunk size
2. Check max_execution_time — chunked uploads may need more time
3. Check the Max Sync File Size setting in the plugin

Diagnostics page

Go to Settings → NC Diagnostics for detailed request/response output including:

• wp_remote_request() test with http_api_curl filter status
• Direct cURL test (bypasses WordPress HTTP API)
• Nextcloud status.php connectivity check
• PHP version, cURL version, SSL info, WordPress HTTP transport type

License

GPL-2.0-or-later