FIX: Fix metadata not upgraded in C++

Author: threecgreen

CHANGELOG.md

@@ -3,8 +3,14 @@
 ## 0.19.1 - TBD
 
 ### Enhancements
+- Added `Upgrade()` method to `Metadata` to update the metadata fields according to a
+  `VersionUpgradePolicy`
 - Added new publisher values for `XNAS.BASIC` and `XNAS.NLS`
 
+### Bug fixes
+- Fixed issue where `Metadata` wasn't upgraded when passing
+  `VersionUpgradePolicy::Upgrade`
+
 ## 0.19.0 - 2024-06-04
 
 ### Enhancements

include/databento/dbn.hpp

@@ -68,6 +68,9 @@ struct Metadata {
   std::vector<std::string> not_found;
   // Symbol mappings containing a native symbol and its mapping intervals.
   std::vector<SymbolMapping> mappings;
+
+  // Upgrades the metadata according to `upgrade_policy` if necessary.
+  void Upgrade(VersionUpgradePolicy upgrade_policy);
 };
 
 inline bool operator==(const MappingInterval& lhs, const MappingInterval& rhs) {

src/dbn.cpp

@@ -2,11 +2,20 @@
 
 #include <array>
 #include <sstream>  // ostringstream
-#include <utility>  // pair
 
+#include "databento/constants.hpp"
 #include "stream_op_helper.hpp"
 
 namespace databento {
+
+void Metadata::Upgrade(VersionUpgradePolicy upgrade_policy) {
+  if (version < kDbnVersion &&
+      upgrade_policy == VersionUpgradePolicy::Upgrade) {
+    version = kDbnVersion;
+    symbol_cstr_len = kSymbolCstrLen;
+  }
+}
+
 std::string ToString(const Metadata& metadata) { return MakeString(metadata); }
 std::ostream& operator<<(std::ostream& stream, const Metadata& metadata) {
   auto helper = StreamOpBuilder{stream}

src/dbn_decoder.cpp

@@ -191,6 +191,7 @@ databento::Metadata DbnDecoder::DecodeMetadata() {
   buffer_idx_ = read_buffer_.size();
   auto metadata = DbnDecoder::DecodeMetadataFields(version_, read_buffer_);
   ts_out_ = metadata.ts_out;
+  metadata.Upgrade(upgrade_policy_);
   return metadata;
 }
 

src/live_blocking.cpp

@@ -130,6 +130,7 @@ databento::Metadata LiveBlocking::Start() {
   auto metadata =
       DbnDecoder::DecodeMetadataFields(version_and_size.first, meta_buffer);
   version_ = metadata.version;
+  metadata.Upgrade(upgrade_policy_);
   return metadata;
 }
 

test/src/dbn_decoder_tests.cpp

@@ -109,7 +109,7 @@ TEST_F(DbnDecoderTests, TestDecodeDefinitionUpgrade) {
   const Metadata ch_metadata = channel_target_->DecodeMetadata();
   const Metadata f_metadata = file_target_->DecodeMetadata();
   EXPECT_EQ(ch_metadata, f_metadata);
-  EXPECT_EQ(ch_metadata.version, 1);
+  EXPECT_EQ(ch_metadata.version, 2);
   EXPECT_EQ(ch_metadata.dataset, dataset::kXnasItch);
   EXPECT_EQ(ch_metadata.schema, Schema::Definition);
   EXPECT_EQ(ch_metadata.start.time_since_epoch().count(), 1633305600000000000);

test/src/live_blocking_tests.cpp

@@ -7,6 +7,7 @@
 #include <memory>
 #include <mutex>   // lock_guard, mutex, unique_lock
 #include <thread>  // this_thread
+#include <utility>
 #include <vector>
 
 #include "databento/constants.hpp"  // dataset
@@ -55,23 +56,28 @@ TEST_F(LiveBlockingTests, TestAuthentication) {
                                   .BuildBlocking();
 }
 
-TEST_F(LiveBlockingTests, TestStart) {
+TEST_F(LiveBlockingTests, TestStartAndUpgrade) {
   constexpr auto kTsOut = true;
-  const mock::MockLsgServer mock_server{dataset::kGlbxMdp3, kTsOut,
-                                        [](mock::MockLsgServer& self) {
-                                          self.Accept();
-                                          self.Authenticate();
-                                          self.Start();
-                                        }};
-
-  LiveBlocking target = builder_.SetAddress(kLocalhost, mock_server.Port())
-                            .SetSendTsOut(kTsOut)
-                            .SetDataset(dataset::kGlbxMdp3)
-                            .BuildBlocking();
-  const auto metadata = target.Start();
-  EXPECT_EQ(metadata.version, 1);
-  EXPECT_TRUE(metadata.has_mixed_schema);
-  EXPECT_EQ(metadata.dataset, dataset::kGlbxMdp3);
+  for (const auto policy_and_version :
+       {std::make_pair(VersionUpgradePolicy::AsIs, 1),
+        std::make_pair(VersionUpgradePolicy::Upgrade, 2)}) {
+    const mock::MockLsgServer mock_server{dataset::kGlbxMdp3, kTsOut,
+                                          [](mock::MockLsgServer& self) {
+                                            self.Accept();
+                                            self.Authenticate();
+                                            self.Start();
+                                          }};
+
+    LiveBlocking target = builder_.SetAddress(kLocalhost, mock_server.Port())
+                              .SetSendTsOut(kTsOut)
+                              .SetDataset(dataset::kGlbxMdp3)
+                              .SetUpgradePolicy(policy_and_version.first)
+                              .BuildBlocking();
+    const auto metadata = target.Start();
+    EXPECT_EQ(metadata.version, policy_and_version.second);
+    EXPECT_TRUE(metadata.has_mixed_schema);
+    EXPECT_EQ(metadata.dataset, dataset::kGlbxMdp3);
+  }
 }
 
 TEST_F(LiveBlockingTests, TestSubscribe) {