diff --git a/.gitignore b/.gitignore new file mode 100644 index 0000000..713d500 --- /dev/null +++ b/.gitignore @@ -0,0 +1,2 @@ +node_modules/ +.env diff --git a/README.md b/README.md index 2058d8d..2734bf1 100644 --- a/README.md +++ b/README.md @@ -8,17 +8,81 @@
-Wordpress post feed -=================== +# WordPress Post Feed -API service for downloading a list of new blog posts. +A lightweight PHP library for fetching, parsing, and caching WordPress RSS feeds with automatic image handling. -The library downloads the feed of posts from Wordpress and provides a simple API for reading them. +The library provides a simple API to download blog posts from any WordPress RSS feed, automatically caches the content to minimize network requests, and handles image downloading and local storage for improved performance and reliability. -Posts from the feed are automatically cached for a set period of time, so they don't have to be downloaded again in each request. +## :sparkles: Key Features -📦 Installation ---------------- +- **Automatic RSS feed parsing** - Extracts posts with title, description, link, date, author, and categories +- **Smart caching system** - Feed content is cached with configurable expiration time (default: 2 hours) +- **Image management** - Automatically downloads and stores post images locally +- **Pagination support** - Built-in `limit` and `offset` parameters for easy pagination +- **Zero-config usage** - Works out of the box without any dependencies when used standalone +- **Nette Framework integration** - Full DI container support with configurable extension +- **Security-first image handling** - Validates image types before saving to prevent malicious files + +## :building_construction: Architecture Overview + +The library consists of four main components that work together to provide a complete feed management solution: + +``` +┌─────────────────────────────────────────────────────────────────────┐ +│ WordPress RSS Feed │ +│ (External WordPress Blog) │ +└───────────────────────────────┬─────────────────────────────────────┘ + │ + ▼ +┌─────────────────────────────────────────────────────────────────────┐ +│ Feed Service │ +│ ┌─────────────────────────────────────────────────────────────┐ │ +│ │ • Downloads RSS feed via cURL │ │ +│ │ • Parses XML using DOMDocument │ │ +│ │ • Extracts post data (title, description, link, date...) │ │ +│ │ • Manages cache read/write operations │ │ +│ │ • Extracts images from post descriptions │ │ +│ └─────────────────────────────────────────────────────────────┘ │ +└───────────────────────────────┬─────────────────────────────────────┘ + │ + ┌───────────────┴───────────────┐ + ▼ ▼ +┌───────────────────────────────┐ ┌───────────────────────────────────┐ +│ Nette Cache │ │ ImageStorage │ +│ ┌─────────────────────────┐ │ │ ┌─────────────────────────────┐ │ +│ │ • FileStorage (default) │ │ │ │ • Downloads images via cURL │ │ +│ │ • Configurable TTL │ │ │ │ • Validates image types │ │ +│ │ • Auto-invalidation │ │ │ │ • Stores to local disk │ │ +│ └─────────────────────────┘ │ │ │ • Generates URLs │ │ +└───────────────────────────────┘ │ └─────────────────────────────┘ │ + └───────────────────────────────────┘ + │ + ▼ + ┌───────────────────────────────────┐ + │ Post Entity │ + │ ┌─────────────────────────────┐ │ + │ │ • title (string) │ │ + │ │ • description (string) │ │ + │ │ • link (string) │ │ + │ │ • date (DateTimeImmutable) │ │ + │ │ • creator (string|null) │ │ + │ │ • categories (array) │ │ + │ │ • mainImageUrl (string|null)│ │ + │ └─────────────────────────────┘ │ + └───────────────────────────────────┘ +``` + +### :package: Components + +| Component | Description | +|-----------|-------------| +| `Feed` | Main service responsible for downloading, parsing, and caching RSS feeds. Orchestrates the entire feed retrieval process. | +| `Post` | Data entity representing a single blog post with all its properties and image URL helpers. | +| `ImageStorage` | Service for downloading, validating, and storing images locally. Provides URL generation for stored images. | +| `WordpressPostFeedExtension` | Nette DI extension for seamless framework integration with full configuration support. | + +## :package: Installation It's best to use [Composer](https://getcomposer.org) for installation, and you can also find the package on [Packagist](https://packagist.org/packages/baraja-core/wordpress-post-feed) and @@ -26,39 +90,72 @@ It's best to use [Composer](https://getcomposer.org) for installation, and you c To install, simply use the command: -``` +```shell $ composer require baraja-core/wordpress-post-feed ``` You can use the package manually by creating an instance of the internal classes, or register a DIC extension to link the services directly to the Nette Framework. -Configuration -------------- +### Requirements + +- PHP 8.0 or higher +- ext-curl extension +- Nette Caching component (installed automatically) + +## :gear: Configuration + +### Standalone Usage + +The library works out of the box without any configuration: + +```php +$feed = new \Baraja\WordPressPostFeed\Feed; +``` + +By default, the `Feed` service will: +- Create a temporary directory for caching in the system temp folder +- Set cache expiration to 2 hours +- Create an `ImageStorage` instance with default settings -If you are installing the package into the Nette Framework, you can simply register the extension: +### Nette Framework Integration + +If you are installing the package into the Nette Framework, register the extension in your configuration: ```yaml extensions: wordpressPostFeed: Baraja\WordPressPostFeed\WordpressPostFeedExtension ``` -However, the extension is not required, as you can create an instance manually: +### Advanced Configuration -```php -$feed = new \Baraja\WordPressPostFeed\Feed; +The extension supports the following configuration options: + +```yaml +wordpressPostFeed: + # Cache expiration time (supports human-readable format) + expirationTime: '2 hours' + + # Absolute path for image storage + imageStoragePath: '%wwwDir%/assets/blog-images' + + # Relative path used in URLs (required when imageStoragePath is set) + imageRelativeStoragePath: 'assets/blog-images' ``` -By default, no dependencies are required. Feed will take care of all dependencies by itself. +| Option | Type | Default | Description | +|--------|------|---------|-------------| +| `expirationTime` | string | `'2 hours'` | Cache expiration time in human-readable format | +| `imageStoragePath` | string | `null` | Absolute filesystem path for storing images | +| `imageRelativeStoragePath` | string | `'wordpress-post-feed'` | Relative URL path for accessing stored images | -How to use ----------- +## :rocket: Basic Usage -Basic usage is simple: +### Loading Posts from a Feed ```php $feed = new \Baraja\WordPressPostFeed\Feed; -$posts = $feed->load('https://blog.mycleverminds.cz/feed/'); +$posts = $feed->load('https://blog.example.com/feed/'); foreach ($posts as $post) { echo $post->getTitle(); @@ -73,46 +170,247 @@ foreach ($posts as $post) { The feed will be downloaded automatically, then cached and further requests will be handled instantly straight from the cache. -If you only need to retrieve some posts from the feed, you can use the `limit` and `offset` arguments: +### Pagination with Limit and Offset + +If you only need to retrieve some posts from the feed, use the `limit` and `offset` arguments: ```php $posts = $feed->load( - url: 'https://blog.mycleverminds.cz/feed/', + url: 'https://blog.example.com/feed/', limit: 3, offset: 1, ); ``` -Posts are automatically cached for the set period (default 2 hours). If the period expires, the cache is automatically invalidated and the next request will have to retrieve the data and rebuild the cache. This retrieval may slow down this request. If you want to handle all requests instantly, the cache for the feed needs to be automatically refreshed by cron. +| Parameter | Type | Default | Description | +|-----------|------|---------|-------------| +| `url` | string | required | The URL of the WordPress RSS feed | +| `limit` | int\|null | `null` | Maximum number of posts to return (null = all) | +| `offset` | int | `0` | Number of posts to skip from the beginning | + +### Post Entity Methods + +The `Post` entity provides the following methods: -Cron will call the following method to refresh the cache: +| Method | Return Type | Description | +|--------|-------------|-------------| +| `getTitle()` | `string` | Returns the post title (HTML tags stripped) | +| `getDescription()` | `string` | Returns the post description/excerpt | +| `getLink()` | `string` | Returns the permalink to the original post | +| `getDate()` | `DateTimeImmutable` | Returns the publication date | +| `getCreator()` | `string\|null` | Returns the author name | +| `getCategories()` | `array` | Returns an array of category names | +| `getMainImageUrl()` | `string\|null` | Returns the original external image URL | +| `getAbsoluteInternalUrl()` | `string\|null` | Returns the absolute URL to locally stored image | +| `getRelativeInternalUrl()` | `string\|null` | Returns the relative URL to locally stored image | + +## :floppy_disk: Caching System + +### How Caching Works + +Posts are automatically cached for the set period (default 2 hours). The caching system operates on two levels: + +1. **Raw feed caching** - The downloaded XML feed is cached to avoid repeated HTTP requests +2. **Parsed post caching** - The parsed `Post` objects are cached separately for each limit/offset combination + +When the cache expires, the next request will: +1. Download the fresh feed +2. Parse all posts +3. Store images locally +4. Update the cache + +### Cache Management + +#### Manual Cache Update + +If you want to refresh the cache before expiration (e.g., via cron job): ```php $feed = new \Baraja\WordPressPostFeed\Feed; -$feed->updateCache('https://blog.mycleverminds.cz/feed/'); +$feed->updateCache('https://blog.example.com/feed/'); ``` -Image manipulation ------------------- +This is useful for ensuring all requests are served from cache instantly, even after expiration. + +#### Clear All Cache + +To completely clear the feed cache: + +```php +$feed = new \Baraja\WordPressPostFeed\Feed; +$feed->clearCache(); +``` + +### Recommended Cron Setup + +For production environments, it's recommended to set up a cron job that refreshes the cache periodically: + +```php +// cron.php - Run every hour +$feed = new \Baraja\WordPressPostFeed\Feed; + +$feedUrls = [ + 'https://blog.example.com/feed/', + 'https://another-blog.com/feed/', +]; + +foreach ($feedUrls as $url) { + $feed->updateCache($url); +} +``` + +This ensures that user requests are always served from cache and never have to wait for feed downloads. + +## :framed_picture: Image Manipulation + +When downloading posts from the feed, images are automatically downloaded and copied to disk. The image storage is provided by the `\Baraja\WordPressPostFeed\ImageStorage` service, which is automatically registered by the library. + +### Default Storage Location -When downloading posts from the feed, images are also automatically downloaded and copied to disk. The image storage is provided by the `\Baraja\WordPressPostFeed\ImageStorage` service, which is automatically registered by the library. The default directory for storing images is `wordpress-post-feed` relative to your `index.php`. +The default directory for storing images is `wordpress-post-feed` relative to your `index.php` (web root). + +### ImageStorage Service Methods The service provides the following methods: | Method | Description | |--------|-------------| | `save(string $url): void` | Downloads the image from the URL and saves it to disk | -| `getInternalPath(string $url): string` | Returns the absolute path for the internal data store. | +| `getInternalPath(string $url): string` | Returns the absolute filesystem path for the image | | `getAbsoluteInternalUrl(string $url): string` | Returns the absolute URL to retrieve the image | | `getRelativeInternalUrl(string $url): string` | Returns the relative URL to retrieve the image | -Working with images is also available directly from the `Post` entity via methods: +### Working with Images from Posts + +Working with images is also available directly from the `Post` entity: + +```php +foreach ($posts as $post) { + // Original external URL (from WordPress) + $externalUrl = $post->getMainImageUrl(); + + // Local absolute URL (your domain) + $absoluteUrl = $post->getAbsoluteInternalUrl(); + + // Local relative URL (for use in templates) + $relativeUrl = $post->getRelativeInternalUrl(); +} +``` + +### Supported Image Formats + +The library validates downloaded images and supports the following formats: + +| Format | Constant | +|--------|----------| +| JPEG | `ImageStorage::JPEG` | +| PNG | `ImageStorage::PNG` | +| GIF | `ImageStorage::GIF` | +| WebP | `ImageStorage::WEBP` | +| BMP | `ImageStorage::BMP` | + +If a downloaded file is not a valid image of these types, a `RuntimeException` is thrown to prevent potential security issues. + +### Image Naming Strategy + +Images are stored with a deterministic naming scheme to prevent collisions and ensure readability: + +1. A 7-character MD5 hash prefix is generated from the URL +2. The original filename is sanitized (webalized) and truncated to 64 characters +3. Files are organized into subdirectories based on WordPress date structure (YYYY-MM) or URL hash + +Example: `https://blog.example.com/wp-content/uploads/2024/03/my-image.jpg` becomes: +``` +wordpress-post-feed/2024-03/a1b2c3d-my-image.jpg +``` + +## :hammer_and_wrench: Advanced Usage + +### Custom Cache Storage + +You can provide your own cache storage implementation: + +```php +use Nette\Caching\Storages\MemcachedStorage; + +$memcached = new Memcached; +$memcached->addServer('localhost', 11211); + +$storage = new MemcachedStorage($memcached); +$feed = new \Baraja\WordPressPostFeed\Feed(storage: $storage); +``` + +### Custom Image Storage Location + +```php +$imageStorage = new \Baraja\WordPressPostFeed\ImageStorage( + storagePath: '/var/www/html/assets/blog-images', + relativeStoragePath: 'assets/blog-images', +); + +$feed = new \Baraja\WordPressPostFeed\Feed(imageStorage: $imageStorage); +``` + +### Custom Expiration Time + +```php +$feed = new \Baraja\WordPressPostFeed\Feed( + expirationTime: '30 minutes', +); +``` + +Supported time formats include: `'1 hour'`, `'30 minutes'`, `'2 days'`, etc. + +### Dependency Injection in Nette + +When using the Nette Framework, you can inject the services directly: + +```php +final class BlogPresenter extends Nette\Application\UI\Presenter +{ + public function __construct( + private \Baraja\WordPressPostFeed\Feed $feed, + ) { + } + + public function renderDefault(): void + { + $this->template->posts = $this->feed->load( + url: 'https://blog.example.com/feed/', + limit: 5, + ); + } +} +``` + +## :warning: Error Handling + +The library handles errors gracefully: + +- **Empty feed response** - Throws `RuntimeException` with descriptive message +- **Invalid image format** - Throws `RuntimeException` to prevent security issues +- **Broken image URLs** - Triggers a warning but continues processing +- **Invalid feed URLs** - Triggers a warning but continues processing +- **Missing absolute URL in CLI** - Throws `LogicException` with guidance + +Example of handling errors: + +```php +try { + $posts = $feed->load('https://blog.example.com/feed/'); +} catch (\RuntimeException $e) { + // Handle feed loading errors + error_log('Feed error: ' . $e->getMessage()); +} +``` + +## :bust_in_silhouette: Author + +**Jan Barasek** -- `getAbsoluteInternalUrl()` -- `getRelativeInternalUrl()` -- `getMainImageUrl()` +- Website: [https://baraja.cz](https://baraja.cz) +- GitHub: [@janbarasek](https://github.com/janbarasek) -📄 License ------------ +## :page_facing_up: License -`baraja-core/wordpress-post-feed` is licensed under the MIT license. See the [LICENSE](https://github.com/baraja-core/template/blob/master/LICENSE) file for more details. +`baraja-core/wordpress-post-feed` is licensed under the MIT license. See the [LICENSE](https://github.com/baraja-core/wordpress-post-feed/blob/master/LICENSE) file for more details.