SERVER-22234 The Validate Command Should Work with failIndexKeyTooLong

4 files changed, 35 insertions, 11 deletions

diff --git a/src/mongo/db/catalog/collection.cpp b/src/mongo/db/catalog/collection.cpp
index 596c80d396b..bc14618b4b9 100644
--- a/src/mongo/db/catalog/collection.cpp
+++ b/src/mongo/db/catalog/collection.cpp
@@ -54,6 +54,7 @@
 #include "mongo/db/ops/update_driver.h"
 #include "mongo/db/ops/update_request.h"
 #include "mongo/db/repl/replication_coordinator_global.h"
+#include "mongo/db/server_parameters.h"
 #include "mongo/db/service_context.h"
 #include "mongo/db/storage/mmap_v1/mmap_v1_options.h"
 #include "mongo/db/storage/record_fetcher.h"
@@ -925,12 +926,26 @@ void validateIndexKeyCount(OperationContext* txn,
                            int64_t numIdxKeys,
                            int64_t numRecs,
                            ValidateResults* results) {
+    if (!failIndexKeyTooLong) {
+        string warning =
+            "the server is configured with {failIndexKeyTooLong: false}. Validation failures "
+            "resulting from having fewer index entries than documents are downgraded from errors "
+            "to warnings";
+        results->warnings.push_back(warning);
+    }
+
     if (idx.isIdIndex() && numIdxKeys != numRecs) {
-        string err = str::stream() << "number of _id index entries (" << numIdxKeys
+        string msg = str::stream() << "number of _id index entries (" << numIdxKeys
                                    << ") does not match the number of documents (" << numRecs
                                    << ")";
-        results->errors.push_back(err);
-        results->valid = false;
+
+        if (failIndexKeyTooLong) {
+            results->errors.push_back(msg);
+            results->valid = false;
+        } else {
+            results->warnings.push_back(msg);
+        }
+
         return;  // Avoid failing the next two checks, they just add redundant/confusing messages
     }
     if (!idx.isMultikey(txn) && numIdxKeys > numRecs) {
@@ -944,11 +959,16 @@ void validateIndexKeyCount(OperationContext* txn,
     //  index plugin with different semantics.
     if (!idx.isSparse() && !idx.isPartial() && idx.getAccessMethodName() == "" &&
         numIdxKeys < numRecs) {
-        string err = str::stream() << "index " << idx.indexName()
+        string msg = str::stream() << "index " << idx.indexName()
                                    << " is not sparse or partial, but has fewer entries ("
                                    << numIdxKeys << ") than documents (" << numRecs << ")";
-        results->errors.push_back(err);
-        results->valid = false;
+
+        if (failIndexKeyTooLong) {
+            results->errors.push_back(msg);
+            results->valid = false;
+        } else {
+            results->warnings.push_back(msg);
+        }
     }
 }
 }  // namespace
diff --git a/src/mongo/db/commands/validate.cpp b/src/mongo/db/commands/validate.cpp
index 41d5b4afdb8..b4f87e353b7 100644
--- a/src/mongo/db/commands/validate.cpp
+++ b/src/mongo/db/commands/validate.cpp
@@ -107,15 +107,15 @@ public:
         if (!status.isOK())
             return appendCommandStatus(result, status);
 
-        result.appendBool("valid", results.valid);
-        result.append("errors", results.errors);
-
         if (!full) {
-            result.append(
-                "warning",
+            results.warnings.push_back(
                 "Some checks omitted for speed. use {full:true} option to do more thorough scan.");
         }
 
+        result.appendBool("valid", results.valid);
+        result.append("warnings", results.warnings);
+        result.append("errors", results.errors);
+
         if (!results.valid) {
             result.append("advice", "ns corrupt. See http://dochub.mongodb.org/core/data-recovery");
         }
diff --git a/src/mongo/db/index/index_access_method.h b/src/mongo/db/index/index_access_method.h
index df62c4ae937..ea9ea90c71c 100644
--- a/src/mongo/db/index/index_access_method.h
+++ b/src/mongo/db/index/index_access_method.h
@@ -28,6 +28,7 @@
 
 #pragma once
 
+#include <atomic>
 #include <memory>
 
 #include "mongo/base/disallow_copying.h"
@@ -40,6 +41,8 @@
 
 namespace mongo {
 
+extern std::atomic<bool> failIndexKeyTooLong;  // NOLINT
+
 class BSONObjBuilder;
 class MatchExpression;
 class UpdateTicket;
diff --git a/src/mongo/db/storage/record_store.h b/src/mongo/db/storage/record_store.h
index b6e973a16ab..2beb8368bf4 100644
--- a/src/mongo/db/storage/record_store.h
+++ b/src/mongo/db/storage/record_store.h
@@ -604,6 +604,7 @@ struct ValidateResults {
     }
     bool valid;
     std::vector<std::string> errors;
+    std::vector<std::string> warnings;
 };
 
 /**