SERVER-42526 IndexBuildInterceptor should store KeyString keys

1 files changed, 24 insertions, 13 deletions

diff --git a/src/mongo/db/storage/key_string.h b/src/mongo/db/storage/key_string.h
index 404f4d9a30c..74fd5fd4d91 100644
--- a/src/mongo/db/storage/key_string.h
+++ b/src/mongo/db/storage/key_string.h
@@ -347,32 +347,43 @@ public:
      */
     std::string toString() const;
 
-    /// Members for Sorter
-    struct SorterDeserializeSettings {
-        SorterDeserializeSettings(Version version) : keyStringVersion(version) {}
-        Version keyStringVersion;
-    };
-
-    void serializeForSorter(BufBuilder& buf) const {
-        buf.appendNum(_ksSize);                                      // Serialize size of Keystring
-        buf.appendBuf(_buffer.get(), _ksSize);                       // Serialize Keystring
-        buf.appendBuf(_buffer.get() + _ksSize, _bufSize - _ksSize);  // Serialize Typebits
+    // Serializes this Value into a storable format with TypeBits information. The serialized
+    // format takes the following form:
+    //   [keystring size][keystring encoding][typebits encoding]
+    void serialize(BufBuilder& buf) const {
+        buf.appendNum(_ksSize);                  // Serialize size of Keystring
+        buf.appendBuf(_buffer.get(), _bufSize);  // Serialize Keystring + Typebits
     }
 
-    static Value deserializeForSorter(BufReader& buf, const SorterDeserializeSettings& settings) {
+    // Deserialize the Value from a serialized format.
+    static Value deserialize(BufReader& buf, KeyString::Version version) {
         const int32_t sizeOfKeystring = buf.read<LittleEndian<int32_t>>();
         const void* keystringPtr = buf.skip(sizeOfKeystring);
 
         BufBuilder newBuf;
         newBuf.appendBuf(keystringPtr, sizeOfKeystring);
 
-        auto typeBits = TypeBits::fromBuffer(settings.keyStringVersion, &buf);  // advances the buf
+        auto typeBits = TypeBits::fromBuffer(version, &buf);  // advances the buf
         if (typeBits.isAllZeros()) {
             newBuf.appendChar(0);
         } else {
             newBuf.appendBuf(typeBits.getBuffer(), typeBits.getSize());
         }
-        return {settings.keyStringVersion, sizeOfKeystring, newBuf.len(), newBuf.release()};
+        return {version, sizeOfKeystring, newBuf.len(), newBuf.release()};
+    }
+
+    /// Members for Sorter
+    struct SorterDeserializeSettings {
+        SorterDeserializeSettings(Version version) : keyStringVersion(version) {}
+        Version keyStringVersion;
+    };
+
+    void serializeForSorter(BufBuilder& buf) const {
+        serialize(buf);
+    }
+
+    static Value deserializeForSorter(BufReader& buf, const SorterDeserializeSettings& settings) {
+        return deserialize(buf, settings.keyStringVersion);
     }
 
     int memUsageForSorter() const {