feat: add url component (#3684)

* feat: add url library

* fix

bridges/RedditBridge.php

@@ -305,25 +305,30 @@ class RedditBridge extends BridgeAbstract
 
     public function detectParameters($url)
     {
-        $parsed_url = parse_url($url);
-
-        $host = $parsed_url['host'] ?? null;
-
-        if ($host != 'www.reddit.com' && $host != 'old.reddit.com') {
+        try {
+            $urlObject = Url::fromString($url);
+        } catch (UrlException $e) {
             return null;
         }
 
-        $path = explode('/', $parsed_url['path']);
+        $host = $urlObject->getHost();
+        $path = $urlObject->getPath();
 
-        if ($path[1] == 'r') {
+        $pathSegments = explode('/', $path);
+
+        if ($host !== 'www.reddit.com' && $host !== 'old.reddit.com') {
+            return null;
+        }
+
+        if ($pathSegments[1] == 'r') {
             return [
                 'context' => 'single',
-                'r' => $path[2]
+                'r' => $pathSegments[2],
             ];
-        } elseif ($path[1] == 'user') {
+        } elseif ($pathSegments[1] == 'user') {
             return [
                 'context' => 'user',
-                'u' => $path[2]
+                'u' => $pathSegments[2],
             ];
         } else {
             return null;

lib/bootstrap.php

@@ -44,6 +44,7 @@ $files = [
     __DIR__ . '/../lib/utils.php',
     __DIR__ . '/../lib/http.php',
     __DIR__ . '/../lib/logger.php',
+    __DIR__ . '/../lib/url.php',
     // Vendor
     __DIR__ . '/../vendor/parsedown/Parsedown.php',
     __DIR__ . '/../vendor/php-urljoin/src/urljoin.php',

lib/url.php

@@ -0,0 +1,145 @@
+<?php
+
+declare(strict_types=1);
+
+final class UrlException extends \Exception
+{
+}
+
+/**
+ * Intentionally restrictive url parser
+ */
+final class Url
+{
+    private string $scheme;
+    private string $host;
+    private int $port;
+    private string $path;
+    private ?string $queryString;
+
+    private function __construct()
+    {
+    }
+
+    public static function fromString(string $url): self
+    {
+        if (!self::validate($url)) {
+            throw new UrlException(sprintf('Illegal url: "%s"', $url));
+        }
+
+        $parts = parse_url($url);
+        if ($parts === false) {
+            throw new UrlException(sprintf('Invalid url %s', $url));
+        }
+
+        return (new self())
+            ->withScheme($parts['scheme'] ?? '')
+            ->withHost($parts['host'])
+            ->withPort($parts['port'] ?? 80)
+            ->withPath($parts['path'] ?? '/')
+            ->withQueryString($parts['query'] ?? null);
+    }
+
+    public static function validate(string $url): bool
+    {
+        if (strlen($url) > 1500) {
+            return false;
+        }
+        $pattern = '#^https?://'   // scheme
+            . '([a-z0-9-]+\.?)+'   // one or more domain names
+            . '(\.[a-z]{1,24})?'   // optional global tld
+            . '(:\d+)?'            // optional port
+            . '($|/|\?)#i';        // end of string or slash or question mark
+
+        return preg_match($pattern, $url) === 1;
+    }
+
+    public function getScheme(): string
+    {
+        return $this->scheme;
+    }
+
+    public function getHost(): string
+    {
+        return $this->host;
+    }
+
+    public function getPort(): int
+    {
+        return $this->port;
+    }
+
+    public function getPath(): string
+    {
+        return $this->path;
+    }
+
+    public function getQueryString(): string
+    {
+        return $this->queryString;
+    }
+
+    public function withScheme(string $scheme): self
+    {
+        if (!in_array($scheme, ['http', 'https'])) {
+            throw new UrlException(sprintf('Invalid scheme %s', $scheme));
+        }
+        $clone = clone $this;
+        $clone->scheme = $scheme;
+        return $clone;
+    }
+
+    public function withHost(string $host): self
+    {
+        $clone = clone $this;
+        $clone->host = $host;
+        return $clone;
+    }
+
+    public function withPort(int $port)
+    {
+        $clone = clone $this;
+        $clone->port = $port;
+        return $clone;
+    }
+
+    public function withPath(string $path): self
+    {
+        if (!str_starts_with($path, '/')) {
+            throw new UrlException(sprintf('Path must start with forward slash: %s', $path));
+        }
+        $clone = clone $this;
+        $clone->path = $path;
+        return $clone;
+    }
+
+    public function withQueryString(?string $queryString): self
+    {
+        $clone = clone $this;
+        $clone->queryString = $queryString;
+        return $clone;
+    }
+
+    public function __toString()
+    {
+        if ($this->port === 80) {
+            $port = '';
+        } else {
+            $port = ':' . $this->port;
+        }
+        if ($this->queryString) {
+            $queryString = '?' . $this->queryString;
+        } else {
+            $queryString = '';
+        }
+
+        return sprintf(
+            '%s://%s%s%s%s',
+            $this->scheme,
+            $this->host,
+            $port,
+            $this->path,
+            $queryString
+        );
+    }
+}

tests/UrlTest.php

@@ -0,0 +1,47 @@
+<?php
+
+declare(strict_types=1);
+
+namespace RssBridge\Tests;
+
+use PHPUnit\Framework\TestCase;
+use Url;
+
+class UrlTest extends TestCase
+{
+    public function testBasicUsages()
+    {
+        $urls = [
+            'http://example.com/',
+            'http://example.com:9000/',
+            'https://example.com/',
+            'https://example.com/?foo',
+            'https://example.com/?foo=bar',
+        ];
+        foreach ($urls as $url) {
+            $this->assertSame($url, Url::fromString($url)->__toString());
+        }
+    }
+
+    public function testNormalization()
+    {
+        $urls = [
+            'http://example.com' => 'http://example.com/',
+            'https://example.com/?' => 'https://example.com/',
+            'https://example.com/foo?' => 'https://example.com/foo',
+            'http://example.com:80/' => 'http://example.com/',
+        ];
+        foreach ($urls as $from => $to) {
+            $this->assertSame($to, Url::fromString($from)->__toString());
+        }
+    }
+
+    public function testMutation()
+    {
+        $this->assertSame('http://example.com/foo', (Url::fromString('http://example.com/'))->withPath('/foo')->__toString());
+        $this->assertSame('http://example.com/foo?a=b', (Url::fromString('http://example.com/?a=b'))->withPath('/foo')->__toString());
+        $this->assertSame('http://example.com/', (Url::fromString('http://example.com/'))->withPath('/')->__toString());
+        $this->assertSame('http://example.com/qqq?foo=bar', (Url::fromString('http://example.com/qqq'))->withQueryString('foo=bar')->__toString());
+        $this->assertSame('http://example.net/qqq?foo=bar', (Url::fromString('http://example.com/qqq?foo=bar'))->withHost('example.net')->__toString());
+    }
+}