add missing fields to `GetLiveFilesMetaData()` (#8460)

Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/8460

Reviewed By: jay-zhuang

Differential Revision: D29381865

Pulled By: ajkr

fbshipit-source-id: 47ba54c25f3cc039d72ea32e1df20875795683b3

HISTORY.md

@@ -5,6 +5,7 @@
 
 ### Bug Fixes
 * Blob file checksums are now printed in hexadecimal format when using the `manifest_dump` `ldb` command.
+* `GetLiveFilesMetaData()` now populates the `temperature`, `oldest_ancester_time`, and `file_creation_time` fields of its `LiveFileMetaData` results when the information is available. Previously these fields always contained zero indicating unknown.
 
 ### New Features
 * ldb has a new feature, `list_live_files_metadata`, that shows the live SST files, as well as their LSM storage level and the column family they belong to.

db/version_set.cc

@@ -5552,6 +5552,9 @@ void VersionSet::GetLiveFilesMetaData(std::vector<LiveFileMetaData>* metadata) {
         filemetadata.oldest_blob_file_number = file->oldest_blob_file_number;
         filemetadata.file_checksum = file->file_checksum;
         filemetadata.file_checksum_func_name = file->file_checksum_func_name;
+        filemetadata.temperature = file->temperature;
+        filemetadata.oldest_ancester_time = file->TryGetOldestAncesterTime();
+        filemetadata.file_creation_time = file->TryGetFileCreationTime();
         metadata->push_back(filemetadata);
       }
     }