Implement reference provider based caching

Signed-off-by: Julius Härtl <[email protected]>

lib/private/Collaboration/Reference/FileReferenceProvider.php

@@ -41,8 +41,13 @@ public function __construct(IURLGenerator $urlGenerator, IRootFolder $rootFolder
 		$this->userId = $userSession->getUser() ? $userSession->getUser()->getUID() : null;
 	}
 
+	public function matchReference(string $referenceText): bool {
+		return str_starts_with($referenceText, $this->urlGenerator->getAbsoluteURL('/index.php/f/'))
+			|| str_starts_with($referenceText, $this->urlGenerator->getAbsoluteURL('/f/'));
+	}
+
 	public function resolveReference(string $referenceText): ?IReference {
-		if (str_starts_with($referenceText, $this->urlGenerator->getAbsoluteURL('/index.php/f/')) || str_starts_with($referenceText, $this->urlGenerator->getAbsoluteURL('/f/'))) {
+		if ($this->matchReference($referenceText)) {
 			$reference = new Reference($referenceText);
 			try {
 				$this->fetchReference($reference);
@@ -62,6 +67,10 @@ public function resolveReference(string $referenceText): ?IReference {
 	 * @throws \OC\User\NoUserException
 	 */
 	private function fetchReference(Reference $reference) {
+		if ($this->userId === null) {
+			throw new NotFoundException();
+		}
+
 		$fileId = str_replace($this->urlGenerator->getAbsoluteURL('/index.php/f/'), '', $reference->getId());
 		$fileId = str_replace($this->urlGenerator->getAbsoluteURL('/f/'), '', $fileId);
 
@@ -90,4 +99,12 @@ private function fetchReference(Reference $reference) {
 			'preview-available' => false
 		]);
 	}
+
+	public function isGloballyCachable(): bool {
+		return false;
+	}
+
+	public function getCacheKey(string $referenceId): string {
+		return $this->userId;
+	}
 }

lib/private/Collaboration/Reference/LinkReferenceProvider.php

@@ -44,12 +44,16 @@ public function __construct(IClientService $clientService, LoggerInterface $logg
 		$this->systemConfig = $systemConfig;
 	}
 
-	public function resolveReference(string $referenceText): ?IReference {
+	public function matchReference(string $referenceText): bool {
 		if ($this->systemConfig->getValue('reference_opengraph', true) !== true) {
-			return null;
+			return false;
 		}
 
-		if (preg_match(self::URL_PATTERN, $referenceText)) {
+		return (bool)preg_match(self::URL_PATTERN, $referenceText);
+	}
+
+	public function resolveReference(string $referenceText): ?IReference {
+		if ($this->matchReference($referenceText)) {
 			$reference = new Reference($referenceText);
 			$this->fetchReference($reference);
 			return $reference;
@@ -87,4 +91,12 @@ private function fetchReference(Reference $reference) {
 			$reference->setImageUrl($object->images[0]->url);
 		}
 	}
+
+	public function isGloballyCachable(): bool {
+		return true;
+	}
+
+	public function getCacheKey(string $referenceId): string {
+		return '';
+	}
 }

lib/private/Collaboration/Reference/ReferenceManager.php

@@ -54,20 +54,31 @@ public function extractReferences(string $text): array {
 	}
 
 	public function resolveReference(string $referenceId): ?IReference {
-		$cached = $this->cache->get($referenceId);
+		$matchedProvider = null;
+		foreach ($this->providers as $provider) {
+			$matchedProvider = $provider->matchReference($referenceId) ? $provider : null;
+		}
+
+		if ($matchedProvider === null) {
+			$matchedProvider = $this->linkReferenceProvider;
+		}
+
+		$cacheKey = md5(serialize([
+			$matchedProvider->isGloballyCachable() ? 0 : $matchedProvider->getCacheKey($referenceId),
+			$referenceId
+		]));
+		$cached = $this->cache->get($cacheKey);
 		if ($cached) {
-			// TODO: Figure out caching for references that depend on the viewer user
 			return Reference::fromCache($cached);
 		}
-		foreach ($this->providers as $provider) {
-			$reference = $provider->resolveReference($referenceId);
-			if ($reference) {
-				$this->cache->set($referenceId, Reference::toCache($reference), 60);
-				return $reference;
-			}
+
+		$reference = $matchedProvider->resolveReference($referenceId);
+		if ($reference) {
+			$this->cache->set($cacheKey, Reference::toCache($reference), 60);
+			return $reference;
 		}
 
-		return $this->linkReferenceProvider->resolveReference($referenceId);
+		return null;
 	}
 
 	public function registerReferenceProvider(IReferenceProvider $provider): void {

lib/public/Collaboration/Reference/IReferenceProvider.php

@@ -23,5 +23,8 @@
 namespace OCP\Collaboration\Reference;
 
 interface IReferenceProvider {
+	public function matchReference(string $referenceText): bool;
 	public function resolveReference(string $referenceText): ?IReference;
+	public function isGloballyCachable(): bool;
+	public function getCacheKey(string $referenceId): string;
 }