SERVER-36199 Put allPaths index creation behind a query knob

5 files changed, 57 insertions, 24 deletions

diff --git a/src/mongo/db/catalog/index_key_validate.cpp b/src/mongo/db/catalog/index_key_validate.cpp
index e4b86cf0a3d..3feddcaf30d 100644
--- a/src/mongo/db/catalog/index_key_validate.cpp
+++ b/src/mongo/db/catalog/index_key_validate.cpp
@@ -45,6 +45,7 @@
 #include "mongo/db/matcher/expression_parser.h"
 #include "mongo/db/namespace_string.h"
 #include "mongo/db/query/collation/collator_factory_interface.h"
+#include "mongo/db/query/query_knobs.h"
 #include "mongo/db/service_context.h"
 #include "mongo/util/fail_point_service.h"
 #include "mongo/util/mongoutils/str.h"
@@ -118,6 +119,13 @@ Status validateKeyPattern(const BSONObj& key, IndexDescriptor::IndexVersion inde
                 code, mongoutils::str::stream() << "Unknown index plugin '" << pluginName << '\'');
     }
 
+    if (pluginName == IndexNames::ALLPATHS && !internalQueryAllowAllPathsIndexes.load()) {
+        // TODO: SERVER-36198 remove this check once AllPaths indexes are complete.
+        return Status(
+            ErrorCodes::NotImplemented,
+            "Cannot use an allPaths index without enabling internalQueryAllowAllPathsIndexes");
+    }
+
     BSONObjIterator it(key);
     while (it.more()) {
         BSONElement keyElement = it.next();
diff --git a/src/mongo/db/catalog/index_key_validate_test.cpp b/src/mongo/db/catalog/index_key_validate_test.cpp
index cc8978d0673..1d170fbbde7 100644
--- a/src/mongo/db/catalog/index_key_validate_test.cpp
+++ b/src/mongo/db/catalog/index_key_validate_test.cpp
@@ -36,6 +36,7 @@
 #include "mongo/bson/bsonmisc.h"
 #include "mongo/bson/bsonobjbuilder.h"
 #include "mongo/db/index/index_descriptor.h"
+#include "mongo/db/query/query_knobs.h"
 #include "mongo/unittest/unittest.h"
 
 namespace mongo {
@@ -45,6 +46,31 @@ namespace {
 using IndexVersion = IndexDescriptor::IndexVersion;
 using index_key_validate::validateKeyPattern;
 
+/**
+ * Helper class to ensure proper FCV & test commands enabled.
+ * TODO: Remove test command enabling/disabling in SERVER-36198
+ */
+class TestCommandQueryKnobGuard {
+
+public:
+    TestCommandQueryKnobGuard() {
+        _prevEnabled = getTestCommandsEnabled();
+        setTestCommandsEnabled(true);
+
+        _prevKnobEnabled = internalQueryAllowAllPathsIndexes.load();
+        internalQueryAllowAllPathsIndexes.store(true);
+    }
+
+    ~TestCommandQueryKnobGuard() {
+        setTestCommandsEnabled(_prevEnabled);
+        internalQueryAllowAllPathsIndexes.store(_prevKnobEnabled);
+    }
+
+private:
+    bool _prevEnabled;
+    bool _prevKnobEnabled;
+};
+
 TEST(IndexKeyValidateTest, KeyElementValueOfSmallPositiveIntSucceeds) {
     for (auto indexVersion : IndexDescriptor::getSupportedIndexVersions()) {
         ASSERT_OK(validateKeyPattern(BSON("x" << 1), indexVersion));
@@ -237,77 +263,61 @@ TEST(IndexKeyValidateTest, KeyElementNameTextSucceedsOnTextIndex) {
 }
 
 TEST(IndexKeyValidateTest, KeyElementNameAllPathsSucceedsOnSubPath) {
-    const bool temp = getTestCommandsEnabled();
-    setTestCommandsEnabled(true);
+    TestCommandQueryKnobGuard guard;
     ASSERT_OK(validateKeyPattern(BSON("a.$**" << 1), IndexVersion::kV2));
-    setTestCommandsEnabled(temp);
 }
 
 TEST(IndexKeyValidateTest, KeyElementNameAllPathsSucceeds) {
-    const bool temp = getTestCommandsEnabled();
-    setTestCommandsEnabled(true);
+    TestCommandQueryKnobGuard guard;
     ASSERT_OK(validateKeyPattern(BSON("$**" << 1), IndexVersion::kV2));
-    setTestCommandsEnabled(temp);
 }
 
 TEST(IndexKeyValidateTest, KeyElementNameAllPathsFailsOnRepeat) {
-    const bool temp = getTestCommandsEnabled();
-    setTestCommandsEnabled(true);
+    TestCommandQueryKnobGuard guard;
     auto status = validateKeyPattern(BSON("$**.$**" << 1), IndexVersion::kV2);
     ASSERT_NOT_OK(status);
     ASSERT_EQ(status, ErrorCodes::CannotCreateIndex);
-    setTestCommandsEnabled(temp);
 }
 
 TEST(IndexKeyValidateTest, KeyElementNameAllPathsFailsOnSubPathRepeat) {
-    const bool temp = getTestCommandsEnabled();
-    setTestCommandsEnabled(true);
+    TestCommandQueryKnobGuard guard;
     auto status = validateKeyPattern(BSON("a.$**.$**" << 1), IndexVersion::kV2);
     ASSERT_NOT_OK(status);
     ASSERT_EQ(status, ErrorCodes::CannotCreateIndex);
-    setTestCommandsEnabled(temp);
 }
 
 TEST(IndexKeyValidateTest, KeyElementNameAllPathsFailsOnCompound) {
-    const bool temp = getTestCommandsEnabled();
-    setTestCommandsEnabled(true);
+    TestCommandQueryKnobGuard guard;
     auto status = validateKeyPattern(BSON("$**" << 1 << "a" << 1), IndexVersion::kV2);
     ASSERT_NOT_OK(status);
     ASSERT_EQ(status, ErrorCodes::CannotCreateIndex);
-    setTestCommandsEnabled(temp);
 }
 
 TEST(IndexKeyValidateTest, KeyElementNameAllPathsFailsOnIncorrectValue) {
-    const bool temp = getTestCommandsEnabled();
-    setTestCommandsEnabled(true);
+    TestCommandQueryKnobGuard guard;
     auto status = validateKeyPattern(BSON("$**" << false), IndexVersion::kV2);
     ASSERT_NOT_OK(status);
     ASSERT_EQ(status, ErrorCodes::CannotCreateIndex);
-    setTestCommandsEnabled(temp);
 }
 
 TEST(IndexKeyValidateTest, KeyElementNameAllPathsFailsWhenValueIsPluginNameWithInvalidKeyName) {
     // TODO: Remove test command enabling/disabling in SERVER-36198
-    const bool temp = getTestCommandsEnabled();
-    setTestCommandsEnabled(true);
+    TestCommandQueryKnobGuard guard;
     auto status = validateKeyPattern(BSON("a"
                                           << "allPaths"),
                                      IndexVersion::kV2);
     ASSERT_NOT_OK(status);
     ASSERT_EQ(status, ErrorCodes::CannotCreateIndex);
-    setTestCommandsEnabled(temp);
 }
 
 TEST(IndexKeyValidateTest, KeyElementNameAllPathsFailsWhenValueIsPluginNameWithValidKeyName) {
     // TODO: Remove test command enabling/disabling in SERVER-36198
-    const bool temp = getTestCommandsEnabled();
-    setTestCommandsEnabled(true);
+    TestCommandQueryKnobGuard guard;
     auto status = validateKeyPattern(BSON("$**"
                                           << "allPaths"),
                                      IndexVersion::kV2);
     ASSERT_NOT_OK(status);
     ASSERT_EQ(status, ErrorCodes::CannotCreateIndex);
-    setTestCommandsEnabled(temp);
 }
 
 }  // namespace
diff --git a/src/mongo/db/catalog/index_spec_validate_test.cpp b/src/mongo/db/catalog/index_spec_validate_test.cpp
index e49d09eb675..35dfc7adbe9 100644
--- a/src/mongo/db/catalog/index_spec_validate_test.cpp
+++ b/src/mongo/db/catalog/index_spec_validate_test.cpp
@@ -40,6 +40,7 @@
 #include "mongo/db/commands/test_commands_enabled.h"
 #include "mongo/db/namespace_string.h"
 #include "mongo/db/query/collation/collator_interface_mock.h"
+#include "mongo/db/query/query_knobs.h"
 #include "mongo/db/query/query_test_service_context.h"
 #include "mongo/db/server_options.h"
 #include "mongo/unittest/unittest.h"
@@ -67,15 +68,21 @@ public:
         // TODO: Remove test command enabling/disabling in SERVER-36198
         _prevEnabled = getTestCommandsEnabled();
         setTestCommandsEnabled(true);
+
+        // TODO: Remove knob enabling/disabling in SERVER-36198.
+        _prevKnobEnabled = internalQueryAllowAllPathsIndexes.load();
+        internalQueryAllowAllPathsIndexes.store(true);
     }
 
     ~TestCommandFcvGuard() {
         serverGlobalParams.featureCompatibility.setVersion(_prevVersion);
         setTestCommandsEnabled(_prevEnabled);
+        internalQueryAllowAllPathsIndexes.store(_prevKnobEnabled);
     }
 
 private:
     bool _prevEnabled;
+    bool _prevKnobEnabled;
     ServerGlobalParams::FeatureCompatibility::Version _prevVersion;
 };
 
diff --git a/src/mongo/db/query/query_knobs.cpp b/src/mongo/db/query/query_knobs.cpp
index 920b04af17d..2ab5f838e4e 100644
--- a/src/mongo/db/query/query_knobs.cpp
+++ b/src/mongo/db/query/query_knobs.cpp
@@ -92,4 +92,6 @@ MONGO_EXPORT_SERVER_PARAMETER(internalQueryPlannerGenerateCoveredWholeIndexScans
 MONGO_EXPORT_SERVER_PARAMETER(internalQueryIgnoreUnknownJSONSchemaKeywords, bool, false);
 
 MONGO_EXPORT_SERVER_PARAMETER(internalQueryProhibitBlockingMergeOnMongoS, bool, false);
+
+MONGO_EXPORT_SERVER_PARAMETER(internalQueryAllowAllPathsIndexes, bool, false);
 }  // namespace mongo
diff --git a/src/mongo/db/query/query_knobs.h b/src/mongo/db/query/query_knobs.h
index a361e875dcc..e17502d0bd7 100644
--- a/src/mongo/db/query/query_knobs.h
+++ b/src/mongo/db/query/query_knobs.h
@@ -130,4 +130,10 @@ extern AtomicInt32 internalDocumentSourceCursorBatchSizeBytes;
 extern AtomicInt32 internalDocumentSourceLookupCacheSizeBytes;
 
 extern AtomicBool internalQueryProhibitBlockingMergeOnMongoS;
+
+//
+// In-progress features.
+//
+// TODO: Remove in SERVER-36198.
+extern AtomicBool internalQueryAllowAllPathsIndexes;
 }  // namespace mongo