Add example with conan workspaces (#33)

* Add example with conan workspaces

* wip

* Update examples/conan_workspace/readme.md

Author: danimtb

README.md

@@ -3,7 +3,7 @@
 [![Conan create ros-kilted](https://github.com/conan-io/ros-conan/actions/workflows/conan-create-ros-kilted.yml/badge.svg)](https://github.com/conan-io/ros-conan/actions/workflows/conan-create-ros-kilted.yml)
 [![License: MIT](https://img.shields.io/badge/License-MIT-blue.svg)](LICENSE)
 
-Conan recipes for building [ROS 2](https://docs.ros.org/) from source. Pull ROS 2 and all its dependencies with a single `conan install`, no `rosdep`, `apt`, `brew` or `choco` required. Works with plain CMake projects and `colcon` workspaces, on Windows, macOS and Linux.
+Conan recipes for building [ROS 2](https://docs.ros.org/) from source. Pull ROS 2 and all its dependencies with a single `conan install`, no `rosdep`, `apt`, `brew` or `choco` required. Works with plain CMake projects, `colcon` workspaces, and [Conan workspaces](https://docs.conan.io/2/tutorial/developing_packages/workspaces.html), on Windows, macOS and Linux.
 
 ---
 
@@ -89,6 +89,7 @@ pinned to. The Conan version `YYYY.MM.DD` maps 1:1 to the rosdistro tag
 | ------------------------------------------------------------- | --------------------------------------------------------------------------- |
 | [`consumer_cmake`](examples/consumer_cmake/readme.md)         | Pure-CMake consumer using `rclcpp` via `CMakeDeps`, no `colcon` needed.     |
 | [`consumer_colcon`](examples/consumer_colcon/readme.md)       | `colcon` workspace consuming the ROS runtime from Conan via `ROSEnv`.       |
+| [`conan_workspace`](examples/conan_workspace/readme.md)       | Same `src/` layout as `consumer_colcon`, orchestrated with a Conan workspace (CMake only). |
 | [`pose_estimation`](examples/pose_estimation/readme.md)       | `ros-kilted` + `opencv` + `tensorflow-lite` publishing a skeleton overlay.  |
 | [`consumer_desktop`](examples/consumer_desktop/readme.md)     | Installs the `desktop` variant and runs its GUI tooling (`rviz2`, `rqt`).  |
 

examples/conan_workspace/ci_test_example.py

@@ -0,0 +1,18 @@
+import platform
+
+from test.examples_tools import VARIANT_ARGS, run
+
+run(
+    f"conan workspace build --profile ../../profiles/ros {VARIANT_ARGS} --build=missing"
+)
+
+if platform.system() == "Windows":
+    run(
+        r"call .\src\consumer_node\build\generators\conanrun.bat && "
+        r".\src\consumer_node\build\Release\consumer_node.exe"
+    )
+else:
+    run(
+        ". ./src/consumer_node/build/Release/generators/conanrun.sh && "
+        "./src/consumer_node/build/Release/consumer_node"
+    )

examples/conan_workspace/conanws.yml

@@ -0,0 +1,6 @@
+name: conan_workspace
+packages:
+  - path: src/dummy_lib
+    ref: dummy_lib/0.1
+  - path: src/consumer_node
+    ref: consumer_node/0.1

examples/conan_workspace/readme.md

@@ -0,0 +1,105 @@
+# conan_workspace
+
+Same layout as [`consumer_colcon`](../consumer_colcon/readme.md) — two packages under
+`src/` — but orchestrated with a [Conan workspace](https://docs.conan.io/2/tutorial/developing_packages/workspaces.html)
+instead of `colcon`. There is no `package.xml`, no `ament_cmake`, and no `colcon`:
+each package is a plain CMake project with its own `conanfile.py`. Workspace packages
+are resolved as [editables](https://docs.conan.io/2/tutorial/developing_packages/editable_packages.html)
+and built in dependency order.
+
+- `dummy_lib` — a static library with no ROS dependencies, used to demonstrate
+  cross-package linking inside the workspace.
+- `consumer_node` — depends on `dummy_lib` and `ros-kilted` (`rclcpp`), prints a
+  message and starts a short-lived node.
+
+[← back to main README](../../README.md)
+
+## Layout
+
+```text
+conan_workspace/
+├── conanws.yml              # workspace root + package inventory
+└── src/
+    ├── dummy_lib/
+    │   ├── conanfile.py     # replaces package.xml
+    │   ├── CMakeLists.txt
+    │   ├── include/
+    │   └── src/
+    └── consumer_node/
+        ├── conanfile.py
+        ├── CMakeLists.txt
+        └── src/
+```
+
+Conan walks up from the current directory until it finds `conanws.yml` and/or
+`conanws.py`; that folder is the workspace root. Paths in `conanws.yml` are
+relative to it.
+
+This example only needs `conanws.yml`. A `conanws.py` is optional Python
+customization (`root_conanfile()` for a monolithic super-build, custom
+`add`/`clean`/`build_order`, or `get_ref()` when name/version come from
+`python_requires`). Orchestrated `conan workspace build` does not use any of
+that.
+
+This example uses the **orchestrated** workspace flow (`conan workspace build`),
+which is the closest analogue to `colcon build`: each package is configured and
+built on its own, in topological order, with workspace members consumed as
+editables.
+
+Conan workspaces are experimental and subject to breaking changes — see the
+[Conan stability notes](https://docs.conan.io/2/introduction.html#stability).
+
+## How it is wired
+
+| Piece | Role |
+| ----- | ---- |
+| [`conanws.yml`](conanws.yml) | Lists `src/dummy_lib` and `src/consumer_node` as workspace packages. |
+| [`src/dummy_lib/conanfile.py`](src/dummy_lib/conanfile.py) | CMake library recipe: `CMakeToolchain` + `CMakeDeps`, `cmake_layout()`. |
+| [`src/consumer_node/conanfile.py`](src/consumer_node/conanfile.py) | Requires `dummy_lib/0.1` (editable, from this workspace) and `ros-kilted/2026.06.17`. |
+| CMake | Plain `find_package(dummy_lib)` / `find_package(rclcpp)` — configs come from Conan, not from sourcing a ROS `setup` script. |
+
+`conan workspace build` is `conan build` for every workspace package, in the
+right order. External dependencies (`ros-kilted` and its graph) are installed
+from the cache/remotes; `dummy_lib` is never looked up as a binary because it
+is in the workspace.
+
+## Prerequisites
+
+- A C++17 compiler.
+- CMake ≥ 3.22 (the [profile](../../profiles/ros) tool-requires `cmake/3.29.3`).
+- Conan 2.31+ (For `conan workspace build`, as the feature has received recent improvements).
+- A Conan remote that exposes `ros-kilted` — see the
+  [main README](../../README.md#quick-start).
+
+## Build & run
+
+From this directory:
+
+```bash
+conan workspace build --profile ../../profiles/ros --build=missing
+```
+
+Then activate the consumer's Conan run environment and execute the node:
+
+**Windows (cmd):**
+
+```bat
+call src\consumer_node\build\generators\conanrun.bat
+src\consumer_node\build\Release\consumer_node.exe
+```
+
+**macOS / Linux (bash/zsh):**
+
+```bash
+. ./src/consumer_node/build/Release/generators/conanrun.sh
+./src/consumer_node/build/Release/consumer_node
+```
+
+Expected output (truncated):
+
+```text
+[dummy_lib] hello from library
+[INFO] [...] [workspace_consumer_node]: Conan workspace consumer_node: rclcpp linked and node started.
+```
+
+The exact CI invocation lives in [`ci_test_example.py`](ci_test_example.py).

examples/conan_workspace/src/consumer_node/CMakeLists.txt

@@ -0,0 +1,8 @@
+cmake_minimum_required(VERSION 3.22)
+project(consumer_node CXX)
+
+find_package(dummy_lib REQUIRED)
+find_package(rclcpp REQUIRED)
+
+add_executable(consumer_node src/main.cpp)
+target_link_libraries(consumer_node PRIVATE dummy_lib::dummy_lib rclcpp::rclcpp)

examples/conan_workspace/src/consumer_node/conanfile.py

@@ -0,0 +1,26 @@
+from conan import ConanFile
+from conan.tools.cmake import CMake, CMakeDeps, CMakeToolchain, cmake_layout
+
+
+class ConsumerNodeConan(ConanFile):
+    name = "consumer_node"
+    version = "0.1"
+    package_type = "application"
+    settings = "os", "compiler", "build_type", "arch"
+    exports_sources = "CMakeLists.txt", "src/*"
+
+    def layout(self):
+        cmake_layout(self)
+
+    def requirements(self):
+        self.requires("dummy_lib/0.1")
+        self.requires("ros-kilted/2026.06.17")
+
+    def generate(self):
+        CMakeDeps(self).generate()
+        CMakeToolchain(self).generate()
+
+    def build(self):
+        cmake = CMake(self)
+        cmake.configure()
+        cmake.build()

examples/conan_workspace/src/consumer_node/src/main.cpp

@@ -0,0 +1,15 @@
+#include <memory>
+
+#include <dummy_lib/print.hpp>
+#include <rclcpp/rclcpp.hpp>
+
+int main(int argc, char ** argv)
+{
+  dummy_lib::print_hello();
+
+  rclcpp::init(argc, argv);
+  auto node = std::make_shared<rclcpp::Node>("workspace_consumer_node");
+  RCLCPP_INFO(node->get_logger(), "Conan workspace consumer_node: rclcpp linked and node started.");
+  rclcpp::shutdown();
+  return 0;
+}

examples/conan_workspace/src/dummy_lib/CMakeLists.txt

@@ -0,0 +1,13 @@
+cmake_minimum_required(VERSION 3.22)
+project(dummy_lib CXX)
+
+add_library(dummy_lib STATIC src/print.cpp)
+target_include_directories(dummy_lib PUBLIC
+  "$<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include>"
+  "$<INSTALL_INTERFACE:include>")
+
+install(TARGETS dummy_lib
+  ARCHIVE DESTINATION lib
+  LIBRARY DESTINATION lib
+  RUNTIME DESTINATION bin)
+install(DIRECTORY include/ DESTINATION include)

examples/conan_workspace/src/dummy_lib/conanfile.py

@@ -0,0 +1,29 @@
+from conan import ConanFile
+from conan.tools.cmake import CMake, CMakeDeps, CMakeToolchain, cmake_layout
+
+
+class DummyLibConan(ConanFile):
+    name = "dummy_lib"
+    version = "0.1"
+    package_type = "static-library"
+    settings = "os", "compiler", "build_type", "arch"
+    exports_sources = "CMakeLists.txt", "src/*", "include/*"
+
+    def layout(self):
+        cmake_layout(self)
+
+    def generate(self):
+        CMakeDeps(self).generate()
+        CMakeToolchain(self).generate()
+
+    def build(self):
+        cmake = CMake(self)
+        cmake.configure()
+        cmake.build()
+
+    def package(self):
+        cmake = CMake(self)
+        cmake.install()
+
+    def package_info(self):
+        self.cpp_info.libs = ["dummy_lib"]

examples/conan_workspace/src/dummy_lib/include/dummy_lib/print.hpp

@@ -0,0 +1,12 @@
+#ifndef DUMMY_LIB__PRINT_HPP_
+#define DUMMY_LIB__PRINT_HPP_
+
+namespace dummy_lib
+{
+
+/** Writes a fixed dummy message to stdout (example library API). */
+void print_hello();
+
+}  // namespace dummy_lib
+
+#endif  // DUMMY_LIB__PRINT_HPP_