--- /dev/null
+<?php
+
+namespace Drupal\workspaces;
+
+use Drupal\Core\Cache\CacheableMetadata;
+use Drupal\Core\Cache\Context\CacheContextInterface;
+
+/**
+ * Defines the WorkspaceCacheContext service, for "per workspace" caching.
+ *
+ * Cache context ID: 'workspace'.
+ */
+class WorkspaceCacheContext implements CacheContextInterface {
+
+ /**
+ * The workspace manager.
+ *
+ * @var \Drupal\workspaces\WorkspaceManagerInterface
+ */
+ protected $workspaceManager;
+
+ /**
+ * Constructs a new WorkspaceCacheContext service.
+ *
+ * @param \Drupal\workspaces\WorkspaceManagerInterface $workspace_manager
+ * The workspace manager.
+ */
+ public function __construct(WorkspaceManagerInterface $workspace_manager) {
+ $this->workspaceManager = $workspace_manager;
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public static function getLabel() {
+ return t('Workspace');
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function getContext() {
+ return $this->workspaceManager->getActiveWorkspace()->id();
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function getCacheableMetadata($type = NULL) {
+ // The active workspace will always be stored in the user's session.
+ $cacheability = new CacheableMetadata();
+ $cacheability->addCacheContexts(['session']);
+
+ return $cacheability;
+ }
+
+}