Merge pull request #5895 from nextcloud/fix/read-only-updates

fix: Ignore pushes of update steps for read only sessions
nextcloud · Jun 13, 2024 · 697b5cd · 697b5cd
2 parents 3cb126a + 672d3a8
commit 697b5cd
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Showing 2 changed files with 18 additions and 1 deletion.
diff --git a/lib/Service/DocumentService.php b/lib/Service/DocumentService.php
@@ -220,11 +220,15 @@ public function writeDocumentState(int $documentId, string $content): void {
 	 */
 	public function addStep(Document $document, Session $session, array $steps, int $version, ?string $shareToken): array {
 		$documentId = $session->getDocumentId();
+		$readOnly = $this->isReadOnly($this->getFileForSession($session, $shareToken), $shareToken);
 		$stepsToInsert = [];
 		$querySteps = [];
 		$newVersion = $version;
 		foreach ($steps as $step) {
 			$message = YjsMessage::fromBase64($step);
+			if ($readOnly && $message->isUpdate()) {
+				continue;
+			}
 			// Filter out query steps as they would just trigger clients to send their steps again
 			if ($message->getYjsMessageType() === YjsMessage::YJS_MESSAGE_SYNC && $message->getYjsSyncType() === YjsMessage::YJS_MESSAGE_SYNC_STEP1) {
 				$querySteps[] = $step;
@@ -233,7 +237,7 @@ public function addStep(Document $document, Session $session, array $steps, int
 			}
 		}
 		if (count($stepsToInsert) > 0) {
-			if ($this->isReadOnly($this->getFileForSession($session, $shareToken), $shareToken)) {
+			if ($readOnly) {
 				throw new NotPermittedException('Read-only client tries to push steps with changes');
 			}
 			$newVersion = $this->insertSteps($document, $session, $stepsToInsert);

diff --git a/lib/YjsMessage.php b/lib/YjsMessage.php
@@ -82,4 +82,17 @@ public function getYjsSyncType(): int {
 		return $syncType;
 	}
 
+	/**
+	 * Based on https://github.com/yjs/y-protocols/blob/master/PROTOCOL.md#handling-read-only-users
+	 */
+	public function isUpdate(): bool {
+		if ($this->getYjsMessageType() === self::YJS_MESSAGE_SYNC) {
+			if (in_array($this->getYjsSyncType(), [self::YJS_MESSAGE_SYNC_STEP2, self::YJS_MESSAGE_SYNC_UPDATE])) {
+				return true;
+			}
+		}
+
+		return false;
+	}
+
 }