Dav Laravel Package

Getting Started

Install sabre/dav via Composer:

composer require sabre/dav

Begin with a minimal working WebDAV server using the included filesystem backend. Create server.php:

<?php
require 'vendor/autoload.php';

use Sabre\DAV;
use Sabre\DAVACL;

$server = new DAV\Server(
    new DAV\FS\Directory('/path/to/webdav/root')
);
$server->setBaseUri('/webdav/');

// Enable basic ACL support (optional but recommended)
$server->addPlugin(new ACL\Simple\ACL([
    'private' => ['{DAV:}read', '{DAV:}write'],
    'public'  => ['{DAV:}read'],
]));

$server->exec();

Run with PHP's built-in server:

php -S localhost:8000 server.php

First use case: verify access via browser at http://localhost:8000/webdav/ or using cadaver CLI tool:

cadaver http://localhost:8000/webdav/

Check documentation at https://sabre.io/dav/ — especially the Getting Started and Server chapters.

Implementation Patterns

Tree abstraction: All data (files, calendars, contacts) is modeled as a tree of INode implementations. Extend Node classes (Directory, File, Collection) or implement INode for custom storage.

Custom backend integration: Implement Backend\BackendInterface (for CardDAV/CalDAV) or extend Backend\AbstractBackend. Use PDO backends as reference (see sabre/dav/src/CalDAV/Backend/PDO.php). For high-performance, prefer iterators over arrays in getChildren().

Event-driven architecture: Leverage Sabre’s event system for hooks:

$server->on('beforeMethod', function ($methodName, $path) {
    if ($methodName === 'PROPFIND') {
        // Log property requests
    }
});

$server->on('afterGetProperties', function ($path, $properties, $outputProperties) {
    unset($outputProperties['{http://example.org}secret']);
});

Plugins: Extend PluginInterface to add features (e.g., custom headers, auth, sync). Key built-in plugins:

• ACLPlugin — access control
• CalDAV\Plugin — calendar scheduling, iTIP messages
• CardDAV\Plugin — vCard imports/exports, addressbook-query
• Browser — human-readable listing
• Locks — file locking (requires Lock\BackendInterface)

Sync workflows: For incremental sync (CalDAV/CardDAV), implement getChanges() in your backend and use Sync\SyncPlugin. Support sync-token and sync-level REPORTs.

Integration tip: Wrap Sabre\DAV\Server in a Laravel controller or middleware. Use route groups for WebDAV paths (e.g., /dav/{user}). Inject auth via middleware and set $server->setBaseUri() dynamically.

Gotchas and Tips

Node path handling: Paths must be absolute and normalized (no .., leading /). The Tree resolves paths using getNodeForPath(). Override it for custom routing (e.g., per-user namespaces like /users/jane/). Caching here (getNodeForPath() caching in 4.7.0+) is critical for performance.

PHP 8.0+ deprecations: Ensure no implicit resource-to-string conversions. Common fixes: cast resources to strings (e.g., (string)$resource), and avoid gettype() comparisons — use is_*().

PROPFIND gotcha: When returning propstat elements, only one of {DAV:}prop or {DAV:}status per propstat. Multiple props in one response must be grouped under one prop.

Locks implementation: Locks require Lock\BackendInterface. Lock\Backend\AbstractBackend provides a DB-based implementation using MySQL/Postgres. Test with litmus test suite — locks and basic suites are critical.

CalDAV iTIP: To enable calendar invitations (e.g., meeting requests), configure IMipPlugin with a mailer (e.g., Symfony Mailer or SwiftMailer) and enable scheduling ($server->addPlugin(new CalDAV\Scheduling\Plugin())).

CardDAV filters: addressbook-query uses filter XML (e.g., {urn:ietf:params:xml:ns:carddav}address-data-filter). Avoid complex regex — use Sabre’s FilterParser where possible.

Extensibility: Override Sabre\DAV\PropFind methods like propFindUnfiltered() (4.6.0+) to bypass property filtering when needed. Use beforeMethod:* and method:* wildcards for events — 4.0+ dropped beforeMethod/method without wildcard.

Debug tip: Enable debug mode:

$server->on('exception', function ($e) {
    error_log($e->getTraceAsString());
});
$server->setDebugLevel(2); // Enable verbose logging

Use Server::addPlugin(new DAV\Browser\Plugin()) for browser GUI inspect requests/responses.