VER: Release 0.48.0

Author: threecgreen

CHANGELOG.md

@@ -1,10 +1,21 @@
 # Changelog
 
+## 0.48.0 - 2026-02-18
+
+### Enhancements
+- Added `SlowReaderBehavior` enum and `LiveBuilder::SetSlowReaderBehavior()` to configure
+  gateway behavior when client falls behind
+- Added `SlowReaderBehavior()` getter to `LiveBlocking` and `LiveThreaded`
+
+### Bug fixes
+- Added conversion for missing schemas for function `RTypeFromSchema`
+- Added explicit optional construction in `json_helpers.hpp` (credit: Enrico Detoma)
+
 ## 0.47.0 - 2026-02-04
 
 ### Enhancements
 - Added Zstd compression support to live clients which can be enabled with
-`LiveBuilder::SetCompression()`. It's disabled by default
+  `LiveBuilder::SetCompression()`. It's disabled by default
 - Added `Compression()` getter to `LiveBlocking` and `LiveThreaded`
 - Upgraded default `httplib` version to 0.30.1
 

CMakeLists.txt

@@ -6,7 +6,7 @@ cmake_minimum_required(VERSION 3.24..4.2)
 
 project(
   databento
-  VERSION 0.47.0
+  VERSION 0.48.0
   LANGUAGES CXX
   DESCRIPTION "Official Databento client library"
 )

include/databento/enums.hpp

@@ -48,6 +48,15 @@ enum class DatasetCondition : std::uint8_t {
   Missing,
 };
 
+// Live session parameter which controls gateway behavior when the client
+// falls behind real time.
+enum class SlowReaderBehavior : std::uint8_t {
+  // Send a warning but continue reading.
+  Warn = 0,
+  // Skip records to catch up.
+  Skip = 1,
+};
+
 // A record type sentinel.
 namespace r_type {
 enum RType : std::uint8_t {
@@ -662,6 +671,7 @@ const char* ToString(SplitDuration duration_interval);
 const char* ToString(Delivery delivery);
 const char* ToString(JobState state);
 const char* ToString(DatasetCondition condition);
+const char* ToString(SlowReaderBehavior slow_reader_behavior);
 const char* ToString(RType r_type);
 const char* ToString(Side side);
 const char* ToString(Action action);
@@ -688,6 +698,7 @@ std::ostream& operator<<(std::ostream& out, SplitDuration duration_interval);
 std::ostream& operator<<(std::ostream& out, Delivery delivery);
 std::ostream& operator<<(std::ostream& out, JobState state);
 std::ostream& operator<<(std::ostream& out, DatasetCondition condition);
+std::ostream& operator<<(std::ostream& out, SlowReaderBehavior slow_reader_behavior);
 std::ostream& operator<<(std::ostream& out, RType r_type);
 std::ostream& operator<<(std::ostream& out, Side side);
 std::ostream& operator<<(std::ostream& out, Action action);

include/databento/live.hpp

@@ -2,6 +2,8 @@
 
 #include <chrono>
 #include <cstddef>
+#include <cstdint>
+#include <optional>
 #include <string>
 
 #include "databento/enums.hpp"  // VersionUpgradePolicy
@@ -53,6 +55,8 @@ class LiveBuilder {
   LiveBuilder& ExtendUserAgent(std::string extension);
   // Sets the compression mode for the read stream.
   LiveBuilder& SetCompression(Compression compression);
+  // Sets the behavior of the gateway when the client falls behind real time.
+  LiveBuilder& SetSlowReaderBehavior(SlowReaderBehavior slow_reader_behavior);
 
   /*
    * Build a live client instance
@@ -80,5 +84,6 @@ class LiveBuilder {
   std::size_t buffer_size_;
   std::string user_agent_ext_;
   Compression compression_{Compression::None};
+  std::optional<SlowReaderBehavior> slow_reader_behavior_{};
 };
 }  // namespace databento

include/databento/live_blocking.hpp

@@ -45,6 +45,9 @@ class LiveBlocking {
     return heartbeat_interval_;
   }
   databento::Compression Compression() const { return compression_; }
+  std::optional<databento::SlowReaderBehavior> SlowReaderBehavior() const {
+    return slow_reader_behavior_;
+  }
   const std::vector<LiveSubscription>& Subscriptions() const { return subscriptions_; }
   std::vector<LiveSubscription>& Subscriptions() { return subscriptions_; }
 
@@ -95,13 +98,15 @@ class LiveBlocking {
                bool send_ts_out, VersionUpgradePolicy upgrade_policy,
                std::optional<std::chrono::seconds> heartbeat_interval,
                std::size_t buffer_size, std::string user_agent_ext,
-               databento::Compression compression);
+               databento::Compression compression,
+               std::optional<databento::SlowReaderBehavior> slow_reader_behavior);
   LiveBlocking(ILogReceiver* log_receiver, std::string key, std::string dataset,
                std::string gateway, std::uint16_t port, bool send_ts_out,
                VersionUpgradePolicy upgrade_policy,
                std::optional<std::chrono::seconds> heartbeat_interval,
                std::size_t buffer_size, std::string user_agent_ext,
-               databento::Compression compression);
+               databento::Compression compression,
+               std::optional<databento::SlowReaderBehavior> slow_reader_behavior);
 
   std::string DetermineGateway() const;
   std::uint64_t Authenticate();
@@ -128,6 +133,7 @@ class LiveBlocking {
   const VersionUpgradePolicy upgrade_policy_;
   const std::optional<std::chrono::seconds> heartbeat_interval_;
   const databento::Compression compression_;
+  const std::optional<databento::SlowReaderBehavior> slow_reader_behavior_;
   detail::LiveConnection connection_;
   std::uint32_t sub_counter_{};
   std::vector<LiveSubscription> subscriptions_;

include/databento/live_threaded.hpp

@@ -55,6 +55,7 @@ class LiveThreaded {
   VersionUpgradePolicy UpgradePolicy() const;
   std::optional<std::chrono::seconds> HeartbeatInterval() const;
   databento::Compression Compression() const;
+  std::optional<databento::SlowReaderBehavior> SlowReaderBehavior() const;
   const std::vector<LiveSubscription>& Subscriptions() const;
   std::vector<LiveSubscription>& Subscriptions();
 
@@ -109,13 +110,15 @@ class LiveThreaded {
                bool send_ts_out, VersionUpgradePolicy upgrade_policy,
                std::optional<std::chrono::seconds> heartbeat_interval,
                std::size_t buffer_size, std::string user_agent_ext,
-               databento::Compression compression);
+               databento::Compression compression,
+               std::optional<databento::SlowReaderBehavior> slow_reader_behavior);
   LiveThreaded(ILogReceiver* log_receiver, std::string key, std::string dataset,
                std::string gateway, std::uint16_t port, bool send_ts_out,
                VersionUpgradePolicy upgrade_policy,
                std::optional<std::chrono::seconds> heartbeat_interval,
                std::size_t buffer_size, std::string user_agent_ext,
-               databento::Compression compression);
+               databento::Compression compression,
+               std::optional<databento::SlowReaderBehavior> slow_reader_behavior);
 
   // unique_ptr to be movable
   std::unique_ptr<Impl> impl_;