Viam C++ SDK

(In)stability Notice

Warning This is a beta release of the Viam C++ SDK. Stability is not guaranteed. Breaking changes are likely to occur, and occur often.

Resources

• Documentation
• Examples

Repository Layout

• src/viam/sdk The implementation of the C++ sdk library
• src/viam/api All the google and viam api autogen files
• src/viam/examples A list of examples

Getting Started

Please see BUILDING.md for instructions on how to use CMake-based build system for this project.

NOTE: Windows is not supported. If you are using Windows, build the project in WSL.

Using Docker for Development

Some Dockerfiles are provided for C++ SDK development, either for developing on the SDK itself, or for module development. The docker images are split up into base images, found in etc/docker/base-images, and an SDK build image. The base images install apt packages required to build and develop the SDK, whereas the SDK build image is meant to be built on top of a base image using multi-stage Docker building.

From the root of this repository, run

docker build -t base/bullseye -f etc/docker/base-images/Dockerfile.debian.bullseye .

This will create a Debian Bullseye base image. Note the use of the -t base/bullseye arg to assign a tag to the image, which is important for the next step. You can then use Dockerfile.sdk-build in a couple different ways.

docker build --build-arg BASE_TAG=base/bullseye --build-arg GIT_TAG=[...] -f etc/docker/Dockerfile.sdk-build .

This will use base/bullseye as a base to build the SDK version provided in GIT_TAG, which should be a tagged release version. The SDK will be cloned from https://github.com/viamrobotics/viam-cpp-sdk/. This is the recommended approach for C++ module development, which should generally be done against a tagged release.

You can also do

docker build --build-arg BASE_TAG=base/bullseye --build-arg REPO_SETUP=copy -f etc/docker/Dockerfile.sdk-build .

Note the use of the build argument REPO_SETUP=copy, which adds a Docker instruction to copy the SDK repo from the current working directory, rather than cloning from GitHub. This approach may make more sense for developing on the SDK itself, or if your C++ SDK development relies on a localversion of the SDK.

The examples above illustrated the use of several --build-arg arguments, namely BASE_TAG, GIT_TAG, and REPO_SETUP. Please see Dockerfile.sdk-build for a complete account of all build arguments and their defaults.

Building Documentation Locally for Testing

The C++ sdk uses Doxygen to generate documentation. An automated workflow will generate and update our documentation on each merge, and publish it to cpp.viam.dev.

Generating documentation locally to observe changes while developing with the C++ SDK is simple. First, make sure doxygen is installed, e.g.,

(on mac) brew install doxygen
(on linux) apt-get install -y doxygen

Next, generate the documentation. From the SDK root, run:

./bin/build-docs.sh

That will run doxygen Doxyfile and create the etc/docs/api/current folder. Then simply open the index.html file in your preferred browser to view the documentation.

A Note on Connectivity and webRTC Functionality

The rust webRTC implementation (which C++ relies on via rust's foreign function interface) is still new, and liable to have bugs. At a minimum, we expect that calls to ShellService::shell() have a high likelihood of strange behavior. If you encounter any issues with streaming requests over webRTC, direct dial (by disabling webrtc as above) should resolve them. And please file a bug report! We will endeavor to be as responsive as possible, and resolve issues as quickly as possible.

License

Copyright 2022 Viam Inc.

Apache 2.0 - See LICENSE file