feat(C/C++): add C/C++ namespace SDK

.bumpversion.toml

@@ -38,6 +38,11 @@ filename = "python/Makefile"
 search = "VERSION = {current_version}"
 replace = "VERSION = {new_version}"
 
+[[tool.bumpversion.files]]
+filename = "cpp/Makefile"
+search = "VERSION = {current_version}"
+replace = "VERSION = {new_version}"
+
 [[tool.bumpversion.files]]
 filename = "rust/Makefile"
 search = "VERSION = {current_version}"
@@ -76,6 +81,12 @@ filename = "rust/reqwest-client.toml"
 search = 'version = "{current_version}"'
 replace = 'version = "{new_version}"'
 
+# C++ version header
+[[tool.bumpversion.files]]
+filename = "cpp/include/lance_namespace/version.h"
+search = 'LANCE_NAMESPACE_VERSION_STRING "{current_version}"'
+replace = 'LANCE_NAMESPACE_VERSION_STRING "{new_version}"'
+
 # Python lance_namespace package
 [[tool.bumpversion.files]]
 filename = "python/lance_namespace/pyproject.toml"
@@ -88,7 +99,6 @@ filename = "python/lance_namespace/pyproject.toml"
 search = 'lance-namespace-urllib3-client=={current_version}'
 replace = 'lance-namespace-urllib3-client=={new_version}'
 
-
 # Java lance-namespace-core module
 [[tool.bumpversion.files]]
 filename = "java/lance-namespace-core/pom.xml"

.github/labeler.yml

@@ -43,6 +43,9 @@ labels:
 - label: rust
   files:
     - "rust\\/.*"
+- label: cpp
+  files:
+    - "cpp\\/.*"
 - label: spec
   files:
     - "spec\\/.*"

CONTRIBUTING.md

@@ -13,7 +13,7 @@ or to add new clients and servers to be generated based on community demand.
 In general, we welcome more generated components to be added as long as 
 the contributor is willing to set up all the automations for generation and publication.
 
-For contributing changes to directory and REST namespaces, please go to the [lance](https://github.com/lance-format/lance) repo.
+For contributing changes to directory and REST namespaces, please go to the [lance-c](https://github.com/lance-format/lance-c) repo for C/C++ and [lance](https://github.com/lance-format/lance) repo for other languages.
 
 For contributing changes to implementations other than the directory and REST namespace, 
 or for adding new namespace implementations,
@@ -32,11 +32,11 @@ This is because Rust uses source code builds, and separating modules across repo
 
 The dependency chain is: `lance-namespace` → `lance` → `lance-namespace-impls`
 
-### Other Languages (e.g. Python, Java)
+### Other Languages (e.g. Python, Java, C/C++)
 
 For Python, Java, and other languages, the core `LanceNamespace` interface and generic connect functionality
 are maintained in **this repository** (e.g., `lance-namespace` for Python, `lance-namespace-core` for Java).
-The core [lance-format/lance](https://github.com/lance-format/lance) repository then imports these modules.
+The core repos [lance-format/lance](https://github.com/lance-format/lance) and [lance-format/lance-c](https://github.com/lance-format/lance-c) then import these modules. 
 
 The reason for this import direction is that `lance-namespace-impls` (REST and directory namespace implementations)
 are used in the Lance Python and Java bindings, and are exposed back through the corresponding language interfaces.
@@ -107,6 +107,8 @@ This repository currently contains the following components:
 | Java Apache Client    | Java     | java/lance-namespace-apache-client     | Generated Java Apache HTTP client for Lance REST Namespace |
 | Java SpringBoot Server| Java     | java/lance-namespace-springboot-server | Generated Java SpringBoot server for Lance REST Namespace  |
 | Rust Reqwest Client   | Rust     | rust/lance-namespace-reqwest-client    | Generated Rust reqwest client for Lance REST Namespace     |
+| C/C++ Core            | C/C++    | cpp/lance_namespace                    | Core LanceNamespace interface and connect functionality    |
+| C/C++ REST Client     | C/C++    | cpp/lance_namespace_rest_client        | Generated C/C++ REST client for Lance REST Namespace       |
 
 
 ## Install uv
@@ -200,5 +202,5 @@ This section describes the CI/CD workflows for automated version management, rel
    - Go to the [Releases page](../../releases) to review the draft
    - Edit release notes if needed
    - Click "Publish release" to:
-     - For stable releases: Trigger automatic publishing for Java, Python, Rust
+     - For stable releases: Trigger automatic publishing for Java, Python, Rust, and C/C++
      - For preview releases: Create a beta release (not published)

Makefile

@@ -26,6 +26,18 @@ gen-rust:
 build-rust:
 	cd rust; make build
 
+.PHONY: clean-cpp
+clean-cpp:
+	cd cpp; make clean
+
+.PHONY: sync gen-cpp
+gen-cpp:
+	cd cpp; make gen
+
+.PHONY: build-cpp
+build-cpp:
+	cd cpp; make build
+
 .PHONY: clean-python
 clean-python:
 	cd python; make clean
@@ -63,10 +75,10 @@ sync:
 	uv sync --all-packages
 
 .PHONY: clean
-clean: clean-rust clean-python clean-java
+clean: clean-rust clean-cpp clean-python clean-java
 
 .PHONY: gen
-gen: lint gen-rust gen-python gen-java
+gen: lint gen-rust gen-cpp gen-python gen-java
 
 .PHONY: build
-build: lint build-docs build-rust build-python build-java
+build: lint build-docs build-rust build-cpp build-python build-java

README.md

@@ -38,6 +38,7 @@ that compute engines can integrate against:
 | Python   | `lance-namespace` | Core interface and connect functionality |
 | Java     | `org.lance:lance-namespace-core` | Core interface for Spark, Flink, Kafka, Trino, Presto |
 | Rust     | `lance-namespace` | Core interface (in [lance-format/lance](https://github.com/lance-format/lance)) |
+| C/C++    | `lance-namespace-cpp` | Core interface and connect functionality |
 
 ## Resources
 

cpp/.clang-format

@@ -0,0 +1,43 @@
+# Lance Namespace C++ SDK — clang-format configuration
+# Enforced by clang-format-20. Run: clang-format-20 -i <file>
+
+BasedOnStyle: Google
+Standard: c++20
+ColumnLimit: 100
+
+# Indent
+IndentWidth: 2
+ContinuationIndentWidth: 4
+AccessModifierOffset: -1
+
+# Braces
+BreakBeforeBraces: Attach
+
+# Include sorting
+IncludeBlocks: Regroup
+IncludeCategories:
+  # Own headers first (lance_namespace/*)
+  - Regex:           '^<lance_namespace/'
+    Priority:        1
+  # System / third-party
+  - Regex:           '^<'
+    Priority:        2
+  # Relative includes
+  - Regex:           '.*'
+    Priority:        3
+SortIncludes: CaseSensitive
+
+# Pointer alignment
+PointerAlignment: Left
+ReferenceAlignment: Left
+
+# Misc
+AlignTrailingComments:
+  Kind: Always
+  OverEmptyLines: 1
+AllowShortFunctionsOnASingleLine: Inline
+AllowShortIfStatementsOnASingleLine: Never
+AllowShortLoopsOnASingleLine: false
+BinPackArguments: false
+BinPackParameters: false
+SpaceBeforeParens: ControlStatements

cpp/CMakeLists.txt

@@ -0,0 +1,45 @@
+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright The Lance Authors
+
+cmake_minimum_required(VERSION 3.22)
+
+project(LanceNamespace
+    VERSION 0.8.7
+    DESCRIPTION "C/C++ SDK for the Lance Namespace interface"
+    HOMEPAGE_URL "https://github.com/lance-format/lance-namespace"
+    LANGUAGES C CXX
+)
+
+# ─── Standards — match lance-c ───────────────────────────────────────────────
+if(NOT DEFINED CMAKE_C_STANDARD OR CMAKE_C_STANDARD LESS 11)
+    set(CMAKE_C_STANDARD 11)
+endif()
+set(CMAKE_C_STANDARD_REQUIRED ON)
+set(CMAKE_C_EXTENSIONS OFF)
+
+if(NOT DEFINED CMAKE_CXX_STANDARD OR CMAKE_CXX_STANDARD LESS 20)
+    set(CMAKE_CXX_STANDARD 20)
+endif()
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+set(CMAKE_CXX_EXTENSIONS OFF)
+
+# ─── Default build type ───────────────────────────────────────────────────────
+if(NOT CMAKE_BUILD_TYPE AND NOT CMAKE_CONFIGURATION_TYPES)
+    set(CMAKE_BUILD_TYPE Release CACHE STRING "Build type" FORCE)
+endif()
+
+# ─── Options ─────────────────────────────────────────────────────────────────
+option(LANCE_NAMESPACE_BUILD_SHARED "Build lance_namespace as a shared library" OFF)
+option(LANCE_NAMESPACE_BUILD_TESTS  "Build unit tests"                          ON)
+
+if(LANCE_NAMESPACE_BUILD_TESTS)
+    enable_testing()
+endif()
+
+# ─── Subdirectories ──────────────────────────────────────────────────────────
+add_subdirectory(lance_namespace)
+
+if(IS_DIRECTORY "${CMAKE_CURRENT_LIST_DIR}/lance_namespace_rest_client" AND
+   EXISTS "${CMAKE_CURRENT_LIST_DIR}/lance_namespace_rest_client/CMakeLists.txt")
+    add_subdirectory(lance_namespace_rest_client)
+endif()

cpp/Makefile

@@ -0,0 +1,85 @@
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+VERSION    = 0.8.7-beta.1
+SPEC       = ../docs/src/spec.yaml
+NPROC     := $(shell nproc 2>/dev/null || sysctl -n hw.logicalcpu 2>/dev/null || echo 4)
+CLANG_FMT ?= clang-format-20
+
+# ─── REST client (cpp-restsdk, generated) ────────────────────────────────────
+
+.PHONY: clean-rest-client
+clean-rest-client:
+	rm -rf lance_namespace_rest_client/include \
+	        lance_namespace_rest_client/src \
+	        lance_namespace_rest_client/model \
+	        lance_namespace_rest_client/api \
+	        lance_namespace_rest_client/CMakeLists.txt
+	mkdir -p lance_namespace_rest_client
+
+.PHONY: gen-rest-client
+gen-rest-client: clean-rest-client
+	uv run openapi-generator-cli generate \
+	  -i $(SPEC) \
+	  -g cpp-restsdk \
+	  -o lance_namespace_rest_client \
+	  --additional-properties=packageName=LanceNamespace,packageVersion=$(VERSION),httpUserAgent=lance-namespace-cpp/$(VERSION)
+	rm -rf lance_namespace_rest_client/.openapi-generator
+	rm -f  lance_namespace_rest_client/.gitignore
+	rm -f  lance_namespace_rest_client/git_push.sh
+	@echo "REST client generated. Update lance_namespace_rest_client/include/lance_namespace_rest_client/lance_namespace.hpp manually if new models were added."
+
+# ─── Core build ──────────────────────────────────────────────────────────────
+
+.PHONY: build-core
+build-core:
+	cmake -S . -B build -DCMAKE_BUILD_TYPE=Release
+	cmake --build build --parallel $(NPROC)
+
+.PHONY: test-core
+test-core: build-core
+	cd build && ctest --output-on-failure -j$(NPROC)
+
+# ─── clang-format ────────────────────────────────────────────────────────────
+
+SOURCES := $(shell find lance_namespace/include lance_namespace/src lance_namespace/tests \
+             -name '*.cpp' -o -name '*.h' -o -name '*.hpp' 2>/dev/null)
+
+.PHONY: format
+format:
+	$(CLANG_FMT) -i $(SOURCES)
+
+.PHONY: format-check
+format-check:
+	@DIFF=$$($(CLANG_FMT) --dry-run --Werror $(SOURCES) 2>&1); \
+	if [ -n "$$DIFF" ]; then \
+	  echo "$$DIFF"; \
+	  echo "Run 'make format' to fix formatting."; \
+	  exit 1; \
+	fi
+	@echo "All files pass clang-format-20."
+
+# ─── Phony aggregates ────────────────────────────────────────────────────────
+
+.PHONY: clean
+clean: clean-rest-client
+	rm -rf build
+
+.PHONY: gen
+gen: gen-rest-client
+
+.PHONY: build
+build: gen build-core
+
+.PHONY: test
+test: test-core
+