Vehicle App C++ Template

The Vehicle App Template for C++ allows to create Vehicle Apps from the Velocitas development model in the C++ programming language.

Important

We successfully migrated our C++ repositories to use version 2 of the Conan package manager. Unfortunately, those changes are not backwards compatible. So, please be aware that recent versions of this C++ app template repository (everything since the conan2 tag) require usage of the Velocitas C++ SDK >= 0.7.0, packages devcontainer-setup >= v3 and github-workflows >= v7, and base images >= v0.4.

If you like to migrate older app repositories created from this template before Conan 2, please have a look at the Conan 2 migration guide below.

Folder structure

• 📁 app - base directory for a vehicle app
  • 📁 src - source code of the vehicle app
  • 📁 tests - tests for the vehicle app

Building

Building the App

To build the App, run the build script:

./build.sh

Starting the runtime

Open the Run Task view in VSCode and select Local Runtime - Up.

Launching the example

With the runtime running in the background, you can run the app. The app must have been build before (see above).

Without debugging

Open the Run Task view in VSCode and select Local Runtime - Run VehicleApp.

With debugging

You can simply launch the example in the Debugging Tab. Make sure the VehicleApp - Debug (Native) is selected at the top. After the selection is done, you can also simply hit F5, to start the debugging session.

Note: This launch task will also make sure to re-build the app if it has been modified!

Run App as Docker container

docker run --rm -it --net="host" -e SDV_MIDDLEWARE_TYPE="native" -e SDV_MQTT_ADDRESS="localhost:1883" -e SDV_VEHICLEDATABROKER_ADDRESS="localhost:55555" localhost:12345/vehicleapp:local

Running in GitHub Codespaces

GitHub Codespaces currently restrict the token that is used within the Codespace to just the current repository. Working on cloned repositories or submodules will not be possible without further setup. To work on other repos, you need to create a personal access token (PAT) here which has full "repo" access. Copy the contents of the PAT and create a Codespace secret called MY_GH_TOKEN and paste the content of your PAT. Finally you need to give the Codespace secret access to the repository of the Codespace, in this case vehicle-app-cpp-template.

Documentation

• Velocitas Development Model
• Vehicle App SDK Overview

Quickstart Tutorials

1. Setup and Explore Development Environment
2. Develop your own Vehicle Model
3. Develop your own Vehicle App

Contribution

• GitHub Issues
• Mailing List
• Contribution

Troubleshooting

Manually installing dependencies

All dependencies of the application should be downloaded and installed automatically once the VSCode DevContainer is created. Should this process fail for whatever reason, you can trigger the manual installation this command:

./install_dependencies.sh

Migrate older app repositories to Conan 2

If you have app repositories created from this template basing on Conan 1 and you like to migrate them to the latest state/Conan 2, here are some hints how to achieve that:

1. You should run velocitas upgrade --ignore-bounds and upgrade packages

   • devenv-github-workflows to a version >= v7.0.0 and
   • devenv-devcontainer-setup to a version >= v3.0.0.

   This will migrate the base image and required Velocitas components to Conan 2.

2. Run velocitas sync to automatically update some local files.

3. You should make sure to update the cli-version to something recent (>= 13.2). Set the version in .velocitas.json.

Now some local files need to be updated manually:

1. conanfile.txt:

   In the [requires] section:

   • Make sure you are referencing all packages used by the app directly. Don't rely on indirect requirements provide by e.g. the C++ SDK:

     [requires]
     +fmt/11.1.1
     +nlohmann_json/3.11.3
     Update the SDK to a version >= 0.7.0:

     vehicle-app-sdk/0.7.0
     In the [generators] section replace cmake as follows:

     [generators]
     -cmake
     +CMakeDeps
     +CMakeToolchain

2. Python requirements.in: Upgrade Conan to version 2

   -conan==1.x.y
   +conan>=2,<3

   Update requirements.txt using pip-compile requirements.in

3. .pre-commit-config.yaml: You should modify the suppression for the build folder:

   -"--suppress=*:build/*",
   +"--suppress=*:build*/*",

4. .gitignore: Add an entry to ignore CMakeUserPresets.json files

   +CMakeUserPresets.json

5. app/Dockerfile - if you are using containerized apps:

   • Update the base-image:

     -FROM ghcr.io/eclipse-velocitas/devcontainer-base-images/cpp:v0.3 as builder
     +FROM ghcr.io/eclipse-velocitas/devcontainer-base-images/cpp:v0.4 AS builder
     You can remove the Conan 1 environment variable (no replacement needed):

     -ENV CONAN_USER_HOME /home/vscode/
     -

6. Now comes the - potentially - tricky part: Update the CMakelist.txt files. Instead of referencing all packages pulled in via Conan using the cmake variable CONAN_LIBS the dependent package now need to be found one by one via find_package. For migration it's best if you compare the changes in the CMakeLists.txt files of this repository between the commit tagged with conan2 and the commit before that and take over the required changes.

Note

If you are using a conanfile.py instead of the conanfile.txt variant, here are some hints:

• The Python file variant is not supported by the Velcitas tooling (especially the gPRC interface tools)!
• Make sure you don't configure cmake_layout in the layout section: This will conflict with the build script provieded by component build-system.