CppBuildTasks: Build C++ code with vcpkg, CMake and Ninja

This extension provides the tasks 'Run vcpkg' and 'Run CMake' to build C++ code on Azure DevOps pipelines. Take a look at examples in the README.md file.

The 'Run vcpkg' task

It uses Git to fetch vcpkg, it builds it, then launches vcpkg to build the specified ports. It sets VCPKG_ROOT environment variable that could be reused by subsequent tasks (i.e. by 'Run CMake').

Caching vcpkg's artifacts on the build pipeline

The "Run vcpkg' task would benefit a lot from the caching capabilities of the Azure Devops Pipelines, as described here. The caching feature is not public yet as of May 2019, documentation and samples on how to leverage it would be provided as the feature is public.

The storage Ninja, vcpkg and its installed ports is as follows:

vcpkg and Ninja are stored at resp $(Build.BinariesDirectory)/vcpkg and $(Build.BinariesDirectory)/downloads/; both are kept (i.e. cached) among multiple runs of the same build definition on the same private agent;
vcpkg's artifacts are stored at $(Build.BinariesDirectory)/vcpkg/installed

The 'Run CMake' task

The 'Run CMake' task works with CMakeLists.txt and CMakeSettings.json. It can leverage the previous execution of the 'Run vcpkg' task by using the VCPKG_ROOT environment variable to:

set the vcpkg's toolchain file if requested, located at $VCPKG_ROOT/scripts/buildsystems/vcpkg.cmake;
set the environment for the provided triplet when building with msvc on Windows (i.e. building in the environment created by launching $VCPKG_ROOT/vcpkg env);

Questions and Answers

Why not one single task?

Because you could use vcpkg only, without CMake. Or you could use CMake without vcpkg.

Would creating an ad-hoc bash/powershell script be easier?

Absolutely! Anyone can use this task as an inspiration for writing their own scripts to suite specific needs. The purpose of the tasks is to streamline and to simplyfy the usage of vcpkg and CMake on build servers.

Please get the source and contribute

The software is provided as is, there is no warranty of any kind. All users are encouraged to get the source code and improve the tasks with fixes and new features.

Tasks' Flowcharts

The 'Run CMake" flowchart

The flowchart has two entry points as it could be used with a CMakeLists.txt or with a CMakeSettings.json file.