Laravel 13 RSS 订阅指南

Laravel 13 可以轻松生成和管理 RSS 订阅源，本文介绍如何构建完整的 RSS 订阅系统。

RSS 概述

RSS 配置

<?php

return [
    'rss' => [
        'feeds' => [
            'main' => [
                'title' => env('RSS_TITLE', config('app.name')),
                'description' => env('RSS_DESCRIPTION', 'Latest articles and updates'),
                'language' => env('RSS_LANGUAGE', 'en-us'),
                'url' => env('RSS_URL', url('/feed')),
                'image' => env('RSS_IMAGE', asset('images/rss-logo.png')),
            ],
        ],
        
        'cache' => [
            'enabled' => true,
            'key' => 'rss.feed',
            'ttl' => 3600,
        ],
        
        'limits' => [
            'items' => 50,
            'title_length' => 100,
            'description_length' => 500,
        ],
    ],
];

RSS 生成器

核心 RSS 类

<?php

namespace App\Services\RSS;

use DateTimeInterface;
use Illuminate\Support\Collection;

class RSSFeed
{
    protected string $title;
    protected string $description;
    protected string $link;
    protected string $language = 'en-us';
    protected ?string $image = null;
    protected ?DateTimeInterface $lastBuildDate = null;
    protected Collection $items;
    
    public function __construct(array $config = [])
    {
        $this->items = collect();
        
        foreach ($config as $key => $value) {
            if (property_exists($this, $key)) {
                $this->$key = $value;
            }
        }
    }
    
    public function setTitle(string $title): self
    {
        $this->title = $title;
        return $this;
    }
    
    public function setDescription(string $description): self
    {
        $this->description = $description;
        return $this;
    }
    
    public function setLink(string $link): self
    {
        $this->link = $link;
        return $this;
    }
    
    public function setLanguage(string $language): self
    {
        $this->language = $language;
        return $this;
    }
    
    public function setImage(string $url, string $title = null, string $link = null): self
    {
        $this->image = [
            'url' => $url,
            'title' => $title ?? $this->title,
            'link' => $link ?? $this->link,
        ];
        return $this;
    }
    
    public function addItem(RSSItem $item): self
    {
        $this->items->push($item);
        return $this;
    }
    
    public function addItems(iterable $items): self
    {
        foreach ($items as $item) {
            $this->addItem($item);
        }
        return $this;
    }
    
    public function getItems(): Collection
    {
        return $this->items;
    }
    
    public function render(): string
    {
        $xml = '<?xml version="1.0" encoding="UTF-8"?>' . "\n";
        $xml .= '<rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom" xmlns:content="http://purl.org/rss/1.0/modules/content/">' . "\n";
        $xml .= '<channel>' . "\n";
        
        $xml .= $this->renderChannel();
        
        foreach ($this->items as $item) {
            $xml .= $item->render();
        }
        
        $xml .= '</channel>' . "\n";
        $xml .= '</rss>';
        
        return $xml;
    }
    
    protected function renderChannel(): string
    {
        $xml = '';
        
        $xml .= '  <title>' . $this->escape($this->title) . '</title>' . "\n";
        $xml .= '  <description>' . $this->escape($this->description) . '</description>' . "\n";
        $xml .= '  <link>' . $this->escape($this->link) . '</link>' . "\n";
        $xml .= '  <language>' . $this->escape($this->language) . '</language>' . "\n";
        
        if ($this->lastBuildDate) {
            $xml .= '  <lastBuildDate>' . $this->lastBuildDate->format(DATE_RSS) . '</lastBuildDate>' . "\n";
        } else {
            $xml .= '  <lastBuildDate>' . now()->format(DATE_RSS) . '</lastBuildDate>' . "\n";
        }
        
        $xml .= '  <atom:link href="' . $this->escape($this->link) . '" rel="self" type="application/rss+xml" />' . "\n";
        
        if ($this->image) {
            $xml .= '  <image>' . "\n";
            $xml .= '    <url>' . $this->escape($this->image['url']) . '</url>' . "\n";
            $xml .= '    <title>' . $this->escape($this->image['title']) . '</title>' . "\n";
            $xml .= '    <link>' . $this->escape($this->image['link']) . '</link>' . "\n";
            $xml .= '  </image>' . "\n";
        }
        
        return $xml;
    }
    
    protected function escape(string $string): string
    {
        return htmlspecialchars($string, ENT_XML1, 'UTF-8');
    }
}

RSS Item 类

<?php

namespace App\Services\RSS;

use DateTimeInterface;

class RSSItem
{
    protected string $title;
    protected string $description;
    protected string $link;
    protected ?string $guid = null;
    protected ?DateTimeInterface $pubDate = null;
    protected ?string $author = null;
    protected array $categories = [];
    protected ?string $enclosure = null;
    protected ?string $content = null;
    
    public function __construct(array $data = [])
    {
        foreach ($data as $key => $value) {
            if (property_exists($this, $key)) {
                $this->$key = $value;
            }
        }
    }
    
    public function setTitle(string $title): self
    {
        $this->title = $title;
        return $this;
    }
    
    public function setDescription(string $description): self
    {
        $this->description = $description;
        return $this;
    }
    
    public function setLink(string $link): self
    {
        $this->link = $link;
        return $this;
    }
    
    public function setGuid(string $guid, bool $isPermaLink = true): self
    {
        $this->guid = $guid;
        return $this;
    }
    
    public function setPubDate(DateTimeInterface $date): self
    {
        $this->pubDate = $date;
        return $this;
    }
    
    public function setAuthor(string $author): self
    {
        $this->author = $author;
        return $this;
    }
    
    public function addCategory(string $category): self
    {
        $this->categories[] = $category;
        return $this;
    }
    
    public function setEnclosure(string $url, int $length = 0, string $type = 'audio/mpeg'): self
    {
        $this->enclosure = [
            'url' => $url,
            'length' => $length,
            'type' => $type,
        ];
        return $this;
    }
    
    public function setContent(string $content): self
    {
        $this->content = $content;
        return $this;
    }
    
    public function render(): string
    {
        $xml = '  <item>' . "\n";
        
        $xml .= '    <title>' . $this->escape($this->title) . '</title>' . "\n";
        $xml .= '    <description><![CDATA[' . $this->description . ']]></description>' . "\n";
        $xml .= '    <link>' . $this->escape($this->link) . '</link>' . "\n";
        
        if ($this->guid) {
            $xml .= '    <guid isPermaLink="false">' . $this->escape($this->guid) . '</guid>' . "\n";
        } else {
            $xml .= '    <guid isPermaLink="true">' . $this->escape($this->link) . '</guid>' . "\n";
        }
        
        if ($this->pubDate) {
            $xml .= '    <pubDate>' . $this->pubDate->format(DATE_RSS) . '</pubDate>' . "\n";
        }
        
        if ($this->author) {
            $xml .= '    <author>' . $this->escape($this->author) . '</author>' . "\n";
        }
        
        foreach ($this->categories as $category) {
            $xml .= '    <category>' . $this->escape($category) . '</category>' . "\n";
        }
        
        if ($this->enclosure) {
            $xml .= '    <enclosure url="' . $this->escape($this->enclosure['url']) . 
                    '" length="' . $this->enclosure['length'] . 
                    '" type="' . $this->escape($this->enclosure['type']) . '" />' . "\n";
        }
        
        if ($this->content) {
            $xml .= '    <content:encoded><![CDATA[' . $this->content . ']]></content:encoded>' . "\n";
        }
        
        $xml .= '  </item>' . "\n";
        
        return $xml;
    }
    
    protected function escape(string $string): string
    {
        return htmlspecialchars($string, ENT_XML1, 'UTF-8');
    }
}

RSS 构建器

内容 RSS 构建

<?php

namespace App\Services\RSS;

use App\Models\Article;
use App\Models\Category;
use Illuminate\Support\Facades\Cache;

class RSSBuilder
{
    protected int $limit = 50;
    protected bool $cacheEnabled = true;
    protected int $cacheTtl = 3600;
    
    public function buildMainFeed(): RSSFeed
    {
        if ($this->cacheEnabled) {
            return Cache::remember('rss.main', $this->cacheTtl, function () {
                return $this->createMainFeed();
            });
        }
        
        return $this->createMainFeed();
    }
    
    protected function createMainFeed(): RSSFeed
    {
        $config = config('rss.feeds.main', []);
        
        $feed = new RSSFeed([
            'title' => $config['title'] ?? config('app.name'),
            'description' => $config['description'] ?? 'Latest articles',
            'link' => $config['url'] ?? url('/feed'),
            'language' => $config['language'] ?? 'en-us',
        ]);
        
        if (!empty($config['image'])) {
            $feed->setImage($config['image']);
        }
        
        $articles = Article::where('status', 'published')
            ->orderBy('published_at', 'desc')
            ->limit($this->limit)
            ->get();
        
        foreach ($articles as $article) {
            $feed->addItem($this->articleToItem($article));
        }
        
        return $feed;
    }
    
    public function buildCategoryFeed(Category $category): RSSFeed
    {
        $feed = new RSSFeed([
            'title' => $category->name . ' - ' . config('app.name'),
            'description' => $category->description ?? "Articles in {$category->name}",
            'link' => route('rss.category', $category),
            'language' => 'en-us',
        ]);
        
        $articles = Article::where('status', 'published')
            ->where('category_id', $category->id)
            ->orderBy('published_at', 'desc')
            ->limit($this->limit)
            ->get();
        
        foreach ($articles as $article) {
            $feed->addItem($this->articleToItem($article));
        }
        
        return $feed;
    }
    
    public function buildAuthorFeed(string $authorId): RSSFeed
    {
        $author = \App\Models\User::findOrFail($authorId);
        
        $feed = new RSSFeed([
            'title' => "Articles by {$author->name}",
            'description' => "Latest articles by {$author->name}",
            'link' => route('rss.author', $author),
            'language' => 'en-us',
        ]);
        
        $articles = Article::where('status', 'published')
            ->where('author_id', $author->id)
            ->orderBy('published_at', 'desc')
            ->limit($this->limit)
            ->get();
        
        foreach ($articles as $article) {
            $feed->addItem($this->articleToItem($article));
        }
        
        return $feed;
    }
    
    protected function articleToItem(Article $article): RSSItem
    {
        $item = new RSSItem([
            'title' => $article->title,
            'description' => $article->excerpt ?? Str::limit(strip_tags($article->content), 300),
            'link' => route('articles.show', $article),
            'guid' => (string) $article->id,
            'pubDate' => $article->published_at,
            'author' => $article->author->email . ' (' . $article->author->name . ')',
            'content' => $article->content,
        ]);
        
        if ($article->categories->isNotEmpty()) {
            foreach ($article->categories as $category) {
                $item->addCategory($category->name);
            }
        }
        
        if ($article->featured_image) {
            $item->setEnclosure(
                Storage::url($article->featured_image),
                Storage::size($article->featured_image),
                'image/jpeg'
            );
        }
        
        return $item;
    }
    
    public function clearCache(): void
    {
        Cache::forget('rss.main');
    }
}

RSS 控制器

<?php

namespace App\Http\Controllers;

use App\Models\Category;
use App\Models\User;
use App\Services\RSS\RSSBuilder;
use Illuminate\Http\Response;

class RSSController extends Controller
{
    protected RSSBuilder $builder;
    
    public function __construct(RSSBuilder $builder)
    {
        $this->builder = $builder;
    }
    
    public function main(): Response
    {
        $feed = $this->builder->buildMainFeed();
        
        return response($feed->render(), 200, [
            'Content-Type' => 'application/xml',
            'Cache-Control' => 'public, max-age=3600',
        ]);
    }
    
    public function category(Category $category): Response
    {
        $feed = $this->builder->buildCategoryFeed($category);
        
        return response($feed->render(), 200, [
            'Content-Type' => 'application/xml',
            'Cache-Control' => 'public, max-age=3600',
        ]);
    }
    
    public function author(User $author): Response
    {
        $feed = $this->builder->buildAuthorFeed($author->id);
        
        return response($feed->render(), 200, [
            'Content-Type' => 'application/xml',
            'Cache-Control' => 'public, max-age=3600',
        ]);
    }
}

RSS 订阅管理

订阅模型

<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Model;

class RSSSubscription extends Model
{
    protected $fillable = [
        'user_id',
        'feed_url',
        'feed_name',
        'last_checked_at',
        'last_item_id',
        'is_active',
    ];
    
    protected $casts = [
        'last_checked_at' => 'datetime',
        'is_active' => 'boolean',
    ];
    
    public function user()
    {
        return $this->belongsTo(User::class);
    }
}

RSS 解析器

<?php

namespace App\Services\RSS;

use SimpleXMLElement;

class RSSParser
{
    public function parse(string $url): array
    {
        $content = @file_get_contents($url);
        
        if ($content === false) {
            throw new \RuntimeException("Unable to fetch RSS feed: {$url}");
        }
        
        $xml = new SimpleXMLElement($content);
        
        return $this->parseFeed($xml);
    }
    
    protected function parseFeed(SimpleXMLElement $xml): array
    {
        $channel = $xml->channel;
        
        $items = [];
        foreach ($channel->item as $item) {
            $items[] = $this->parseItem($item);
        }
        
        return [
            'title' => (string) $channel->title,
            'description' => (string) $channel->description,
            'link' => (string) $channel->link,
            'language' => (string) $channel->language,
            'items' => $items,
        ];
    }
    
    protected function parseItem(SimpleXMLElement $item): array
    {
        $namespaces = $item->getNamespaces(true);
        
        $data = [
            'title' => (string) $item->title,
            'description' => (string) $item->description,
            'link' => (string) $item->link,
            'guid' => (string) $item->guid,
            'pub_date' => (string) $item->pubDate,
            'author' => (string) $item->author,
        ];
        
        if (isset($namespaces['content'])) {
            $content = $item->children($namespaces['content']);
            $data['content'] = (string) $content->encoded;
        }
        
        if ($item->enclosure) {
            $data['enclosure'] = [
                'url' => (string) $item->enclosure['url'],
                'type' => (string) $item->enclosure['type'],
                'length' => (int) $item->enclosure['length'],
            ];
        }
        
        foreach ($item->category as $category) {
            $data['categories'][] = (string) $category;
        }
        
        return $data;
    }
}

RSS 命令

<?php

namespace App\Console\Commands;

use App\Services\RSS\RSSBuilder;
use Illuminate\Console\Command;

class RSSGenerateCommand extends Command
{
    protected $signature = 'rss:generate {--clear-cache : Clear cache before generating}';
    protected $description = 'Generate RSS feeds';
    
    public function handle(RSSBuilder $builder): int
    {
        if ($this->option('clear-cache')) {
            $this->info('Clearing RSS cache...');
            $builder->clearCache();
        }
        
        $this->info('Generating main RSS feed...');
        
        $feed = $builder->buildMainFeed();
        
        $this->info("Feed generated with {$feed->getItems()->count()} items");
        
        return self::SUCCESS;
    }
}

路由配置

<?php

use App\Http\Controllers\RSSController;

Route::get('/feed', [RSSController::class, 'main'])->name('rss.main');
Route::get('/feed/category/{category}', [RSSController::class, 'category'])->name('rss.category');
Route::get('/feed/author/{author}', [RSSController::class, 'author'])->name('rss.author');

总结

Laravel 13 的 RSS 订阅系统支持多种类型的订阅源生成，包括主订阅、分类订阅和作者订阅。通过缓存机制和灵活的配置，可以高效地生成和管理 RSS 订阅源。