check for valid extension namespaces

lode · lode · Aug 23, 2021 · Aug 13, 2019 · Oct 20, 2020 · Oct 20, 2020
commit 867a2247abd9fab7936f7c4fddc87211559e2ed2
diff --git a/src/Document.php b/src/Document.php
@@ -2,6 +2,7 @@
 
 namespace alsvanzelf\jsonapi;
 
+use alsvanzelf\jsonapi\exceptions\DuplicateException;
 use alsvanzelf\jsonapi\exceptions\Exception;
 use alsvanzelf\jsonapi\exceptions\InputException;
 use alsvanzelf\jsonapi\helpers\AtMemberManager;
@@ -190,9 +191,20 @@ public function unsetJsonapiObject() {
 	 * @see https://jsonapi.org/extensions/#extensions
 	 * 
 	 * @param ExtensionInterface $extension
+	 * 
+	 * @throws Exception if namespace uses illegal characters
+	 * @throws DuplicateException if namespace conflicts with another applied extension
 	 */
 	public function applyExtension(ExtensionInterface $extension) {
-		$this->extensions[] = $extension;
+		$namespace = $extension->getNamespace();
+		if (strlen($namespace) < 1 || preg_match('{[^a-zA-Z0-9]}', $namespace) === 1) {
+			throw new Exception('invalid namespace "'.$namespace.'"');
+		}
+		if (isset($this->extensions[$namespace])) {
+			throw new DuplicateException('an extension with namespace "'.$namespace.'" is already applied');
+		}
+
+		$this->extensions[$namespace] = $extension;
 
 		if ($this->jsonapi !== null) {
 			$this->jsonapi->addExtension($extension);

diff --git a/tests/DocumentTest.php b/tests/DocumentTest.php
@@ -2,6 +2,7 @@
 
 namespace alsvanzelf\jsonapiTests;
 
+use alsvanzelf\jsonapi\exceptions\DuplicateException;
 use alsvanzelf\jsonapi\exceptions\Exception;
 use alsvanzelf\jsonapi\exceptions\InputException;
 use alsvanzelf\jsonapi\objects\LinkObject;
@@ -203,6 +204,37 @@ public function testApplyExtension_HappyPath() {
 		$this->assertSame('bar', $array['test:foo']);
 	}
 
+	public function testApplyExtension_InvalidNamespace() {
+		$document  = new Document();
+		$extension = new TestExtension();
+		$extension->setNamespace('foo-bar');
+
+		$this->expectException(Exception::class);
+		$this->expectExceptionMessage('invalid namespace "foo-bar"');
+
+		$document->applyExtension($extension);
+	}
+
+	public function testApplyExtension_ConflictingNamespace() {
+		$document  = new Document();
+
+		$extension1 = new TestExtension();
+		$extension1->setNamespace('foo');
+		$document->applyExtension($extension1);
+
+		$extension2 = new TestExtension();
+		$extension2->setNamespace('bar');
+		$document->applyExtension($extension2);
+
+		$extension3 = new TestExtension();
+		$extension3->setNamespace('foo');
+
+		$this->expectException(DuplicateException::class);
+		$this->expectExceptionMessage('an extension with namespace "foo" is already applied');
+
+		$document->applyExtension($extension3);
+	}
+
 	/**
 	 * @group Profiles
 	 */

diff --git a/tests/SeparateProcessTest.php b/tests/SeparateProcessTest.php
@@ -75,6 +75,7 @@ public function testSendResponse_ContentTypeHeader() {
 	 */
 	public function testSendResponse_ContentTypeHeaderWithExtensions() {
 		$extension = new TestExtension();
+		$extension->setNamespace('one');
 		$extension->setOfficialLink('https://jsonapi.org');
 
 		$document = new Document();
@@ -86,6 +87,7 @@ public function testSendResponse_ContentTypeHeaderWithExtensions() {
 		$this->assertSame(['Content-Type: '.Document::CONTENT_TYPE_OFFICIAL.'; ext="https://jsonapi.org"'], xdebug_get_headers());
 
 		$extension = new TestExtension();
+		$extension->setNamespace('two');
 		$extension->setOfficialLink('https://jsonapi.org/2');
 		$document->applyExtension($extension);