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diff --git a/src/mongo/db/change_stream_serverless_helpers.cpp b/src/mongo/db/change_stream_serverless_helpers.cpp
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+/**
+ *    Copyright (C) 2022-present MongoDB, Inc.
+ *
+ *    This program is free software: you can redistribute it and/or modify
+ *    it under the terms of the Server Side Public License, version 1,
+ *    as published by MongoDB, Inc.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    Server Side Public License for more details.
+ *
+ *    You should have received a copy of the Server Side Public License
+ *    along with this program. If not, see
+ *    <http://www.mongodb.com/licensing/server-side-public-license>.
+ *
+ *    As a special exception, the copyright holders give permission to link the
+ *    code of portions of this program with the OpenSSL library under certain
+ *    conditions as described in each individual source file and distribute
+ *    linked combinations including the program with the OpenSSL library. You
+ *    must comply with the Server Side Public License in all respects for
+ *    all of the code used other than as permitted herein. If you modify file(s)
+ *    with this exception, you may extend this exception to your version of the
+ *    file(s), but you are not obligated to do so. If you do not wish to do so,
+ *    delete this exception statement from your version. If you delete this
+ *    exception statement from all source files in the program, then also delete
+ *    it in the license file.
+ */
+
+#define MONGO_LOGV2_DEFAULT_COMPONENT ::mongo::logv2::LogComponent::kQuery
+
+#include "mongo/db/change_stream_serverless_helpers.h"
+
+#include "mongo/db/catalog_raii.h"
+#include "mongo/db/dbdirectclient.h"
+#include "mongo/db/namespace_string.h"
+#include "mongo/db/server_feature_flags_gen.h"
+#include "mongo/db/server_options.h"
+
+namespace mongo {
+namespace change_stream_serverless_helpers {
+
+bool isChangeCollectionsModeActive() {
+    // A change collection must not be enabled on the config server.
+    if (serverGlobalParams.clusterRole == ClusterRole::ConfigServer) {
+        return false;
+    }
+
+    // TODO SERVER-67267 guard with 'multitenancySupport' and 'isServerless' flag.
+    return serverGlobalParams.featureCompatibility.isVersionInitialized() &&
+        feature_flags::gFeatureFlagServerlessChangeStreams.isEnabled(
+            serverGlobalParams.featureCompatibility);
+}
+
+bool isChangeStreamEnabled(OperationContext* opCtx, const TenantId& tenantId) {
+    auto catalog = CollectionCatalog::get(opCtx);
+
+    // A change stream in the serverless is declared as enabled if both the change collection and
+    // the pre-images collection exist for the provided tenant.
+    // TODO SERVER-66643 Pass 'tenantId' to the pre-images collection.
+    return isChangeCollectionsModeActive() &&
+        static_cast<bool>(catalog->lookupCollectionByNamespace(
+            opCtx, NamespaceString::makeChangeCollectionNSS(tenantId))) &&
+        static_cast<bool>(catalog->lookupCollectionByNamespace(
+            opCtx, NamespaceString::makePreImageCollectionNSS(boost::none)));
+}
+
+const TenantId& getTenantIdForTesting() {
+    static const TenantId kTestTenantId(
+        OID("00000000"   /* timestamp */
+            "0000000000" /* process id */
+            "000000" /* counter */));
+
+    return kTestTenantId;
+}
+
+boost::optional<TenantId> resolveTenantId(boost::optional<TenantId> tenantId) {
+    if (tenantId) {
+        return tenantId;
+    } else if (MONGO_unlikely(internalChangeStreamUseTenantIdForTesting.load())) {
+        return getTenantIdForTesting();
+    }
+
+    return tenantId;
+}
+
+TenantSet getConfigDbTenants(OperationContext* opCtx) {
+    TenantSet tenantIds;
+
+    auto dbNames = CollectionCatalog::get(opCtx)->getAllDbNames();
+    for (auto&& dbName : dbNames) {
+        if (dbName.db() == NamespaceString::kConfigDb && dbName.tenantId()) {
+            tenantIds.insert(*dbName.tenantId());
+        }
+    }
+
+    return tenantIds;
+}
+
+}  // namespace change_stream_serverless_helpers
+}  // namespace mongo