使用 vcpkg 编译 gRPC C++ 示例

Question

我正在尝试使用通过 vcpkg 管理器安装的 grpc 构建和运行 grpc 示例。

我通过克隆和查找 grpc 来安装 vcpkg 管理器，如下所示：

sudo apt-get install -y unzip build-essential
git clone https://github.com/microsoft/vcpkg
cd vcpkg/
./bootstrap-vcpkg.sh -disableMetrics
./vcpkg search grpc
./vcpkg install grpc
export PATH=$PATH:$HOME/vcpkg/downloads/tools/cmake-3.14.0-linux/cmake-3.14.0-Linux-x86_64/bin 

太棒了！所以我想我有grpc。我还需要 protobuf，但它是随 vcpkg 的 grpc 一起安装的。如果我尝试安装 protobuf，我会得到以下输出：

an@ubuntu:~/vcpkg$ ./vcpkg install protobuf
Computing installation plan...
The following packages are already installed:
    protobuf[core]:x64-linux
Package protobuf:x64-linux is already installed

Total elapsed time: 205.3 us

The package protobuf:x64-linux provides CMake targets:

    find_package(protobuf CONFIG REQUIRED)
    target_link_libraries(main PRIVATE protobuf::libprotoc protobuf::libprotobuf protobuf::libprotobuf-lite

为了仔细检查，我使用./vcpkg list 来显示我已安装的所有软件包。这是它的样子。注意：protobuf 和 grpc

adrian@ubuntu:~/vcpkg$ ./vcpkg list
abseil:x64-linux                                   2020-03-03#8     an open-source collection designed to augment th...
c-ares:x64-linux                                   2019-5-2-1       A C library for asynchronous DNS requests
grpc:x64-linux                                     1.31.1           An RPC library and framework
openssl-unix:x64-linux                             1.1.1h           OpenSSL is an open source project that provides ...
openssl:x64-linux                                  1.1.1g#1         OpenSSL is an open source project that provides ...
protobuf:x64-linux                                 3.13.0#2         Protocol Buffers - Google's data interchange format
re2:x64-linux                                      2020-10-01       RE2 is a fast, safe, thread-friendly alternative...
upb:x64-linux                                      2020-08-19       μpb (often written 'upb') is a small protobuf i...
zlib:x64-linux                                     1.2.11#9         A compression library

我们还可以在下面突出显示的/vcpkg/installed/x64-linux/libs 目录中看到 grpc 和 protobuf 的二进制文件：

好的，太好了！所以现在我想尝试使用 vcpkg 管理器插件编译 grpc 的 hello world 示例。在官方 grpc 网站上，他们有构建和编译的快速说明。 （默认情况下，他们在本地安装 grpc，但卸载过程很混乱，这就是我使用 vcpkg 的原因）。所以让我们尝试使用这些 instructions from grpc's quick start guide 进行编译：

mkdir -p cmake/build
pushd cmake/build
cmake -DCMAKE_PREFIX_PATH=$MY_INSTALL_DIR ../..
make -j

重要的是要注意，一开始他们原生安装了 grpc（删除不喜欢的 vcpkg 很麻烦）。他们的指示表明要像这样设置MY_INSTALL_DIR：

export MY_INSTALL_DIR=$HOME/.local
export PATH="$PATH:$MY_INSTALL_DIR/bin"

但这是用于本地安装和编译 grpc 的二进制文件。不幸的是，我不知道 vckpkg 管理器的二进制文件在哪里。我看到 cmake 安装并有一个位于：vcpkg/downloads/tools 的二进制文件，但我没有看到它们各自的二进制文件的 grpc 或 protobuf 文件夹（见下图）。 vcpkg 的二进制文件位于何处？根据 grpc 的官方说明，我应该使用 cmake 并在下面定义这些。

find_package(gRPC CONFIG REQUIRED)
find_package(Protobuf CONFIG REQUIRED)

不幸的是，我对 vcpkg 和依赖项相对较新，但对使用 Makefile 有一点经验（我相信这与 cmake/cmakelists 有很大不同。我从未从头开始制作 cmake 文件，因为我主要使用 Makefile）。有人可以指出正确的方向如何使用 vcpkg 编译和运行这些示例（或提出更好的方法？）我的目标是学习如何使用 vcpkg 并将其集成到现有项目中，例如 gRPC 的示例文件。

更新 1：

我 cd 到示例 hello world 文件夹并按照建议运行以下命令：

mkdir build-dir
cd build-dir
cmake ..
make

当我运行cmake .. 时，出现以下错误：

grpc/examples/cpp/helloworld/build$ cmake ..
CMake Error at /usr/share/cmake-3.16/Modules/CMakeDetermineSystem.cmake:99 (message):
  Could not find toolchain file: /usr/vcpkg/scripts/buildsystems/vcpkg.cmake
Call Stack (most recent call first):
  CMakeLists.txt:24 (project)


CMake Error: CMake was unable to find a build program corresponding to "Unix Makefiles".  CMAKE_MAKE_PROGRAM is not set.  You probably need to select a different build tool.
CMake Error: CMAKE_C_COMPILER not set, after EnableLanguage
CMake Error: CMAKE_CXX_COMPILER not set, after EnableLanguage
-- Configuring incomplete, errors occurred!

这表明我没有使用正确的 cmake（vcpkg 使用的那个。所以我做了一点挖掘，根据这个 vcpkg documentation 我需要将 vcpkg 包与 ./vcpkg integrate install 集成，这会暴露我所有的包在我的系统上，只要我将它指向内部的 cmake。然后它说我应该播种路径：

~/vcpkg$ ./vcpkg integrate install
Applied user-wide integration for this vcpkg root.

CMake projects should use: "-DCMAKE_TOOLCHAIN_FILE=/home/adrian/vcpkg/scripts/buildsystems/vcpkg.cmake"

所以我尝试使用 cmake .. 构建，但我提供了 DCMAKE_TOOL_CHAIN 参数，但我还是像以前一样回到原来的问题。

/grpc/examples/cpp/helloworld/build$ cmake .. "-DCMAKE_TOOLCHAIN_FILE=/home/adrian/vcpkg/scripts/buildsystems/vcpkg.cmake"
CMake Error at /usr/share/cmake-3.16/Modules/CMakeDetermineSystem.cmake:99 (message):
  Could not find toolchain file: /usr/vcpkg/scripts/buildsystems/vcpkg.cmake
Call Stack (most recent call first):
  CMakeLists.txt:24 (project)


CMake Error: CMake was unable to find a build program corresponding to "Unix Makefiles".  CMAKE_MAKE_PROGRAM is not set.  You probably need to select a different build tool.
CMake Error: CMAKE_C_COMPILER not set, after EnableLanguage
CMake Error: CMAKE_CXX_COMPILER not set, after EnableLanguage
-- Configuring incomplete, errors occurred!

Answer 1

看来我导出了 vcpkg 目录中的 错误版本。

我导出了 3.14.0，这是我的 ubuntu 附带的默认 cmake 版本，而不是随 vcpkg 一起安装的 cmake，它是 cmake 版本 3.17.2。下面解决了我的问题，因此我能够在之后编译示例。

export PATH=$PATH:$HOME/vcpkg/downloads/tools/cmake-3.17.2-linux/cmake-3.17.2-Linux-x86_64/bin

检查以确保它已添加到路径中：

a@ubuntu:~/grpc/examples/cpp/helloworld/build$ echo $PATH | grep cmake
/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin:/home/adrian/vcpkg/downloads/tools/cmake-3.17.2-linux/cmake-3.17.2-Linux-x86_64/bin

CD到grpc的examples hello world文件夹并编译：

a@ubuntu:~/grpc/examples/cpp/helloworld$ mkdir build
a@ubuntu:~/grpc/examples/cpp/helloworld$ mkdir build
a@ubuntu:~/grpc/examples/cpp/helloworld$ cd build/
a@ubuntu:~/grpc/examples/cpp/helloworld/build$ cmake .. "-DCMAKE_TOOLCHAIN_FILE=/home/adrian/vcpkg/scripts/buildsystems/vcpkg.cmake"
-- The C compiler identification is GNU 9.3.0
-- The CXX compiler identification is GNU 9.3.0
-- Check for working C compiler: /usr/bin/cc
-- Check for working C compiler: /usr/bin/cc -- works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Detecting C compile features
-- Detecting C compile features - done
-- Check for working CXX compiler: /usr/bin/c++
-- Check for working CXX compiler: /usr/bin/c++ -- works
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Looking for pthread.h
-- Looking for pthread.h - found
-- Performing Test CMAKE_HAVE_LIBC_PTHREAD
-- Performing Test CMAKE_HAVE_LIBC_PTHREAD - Failed
-- Looking for pthread_create in pthreads
-- Looking for pthread_create in pthreads - not found
-- Looking for pthread_create in pthread
-- Looking for pthread_create in pthread - found
-- Found Threads: TRUE  
CMake Warning (dev) at /home/adrian/vcpkg/installed/x64-linux/share/protobuf/protobuf-options.cmake:6 (option):
  Policy CMP0077 is not set: option() honors normal variables.  Run "cmake
  --help-policy CMP0077" for policy details.  Use the cmake_policy command to
  set the policy and suppress this warning.

  For compatibility with older versions of CMake, option is clearing the
  normal variable 'protobuf_MODULE_COMPATIBLE'.
Call Stack (most recent call first):
  /home/adrian/vcpkg/installed/x64-linux/share/protobuf/protobuf-config.cmake:2 (include)
  /home/adrian/vcpkg/installed/x64-linux/share/protobuf/vcpkg-cmake-wrapper.cmake:13 (_find_package)
  /home/adrian/vcpkg/scripts/buildsystems/vcpkg.cmake:481 (include)
  CMakeLists.txt:103 (find_package)
This warning is for project developers.  Use -Wno-dev to suppress it.

-- Using protobuf 
-- Found ZLIB: /home/adrian/vcpkg/installed/x64-linux/debug/lib/libz.a (found version "1.2.11") 
-- Found OpenSSL: /home/adrian/vcpkg/installed/x64-linux/debug/lib/libcrypto.a (found version "1.1.1h")  
-- Found c-ares: /home/adrian/vcpkg/installed/x64-linux/share/c-ares/c-ares-config.cmake (found version "1.15.0") 
-- Using gRPC 1.31.1
-- Configuring done
-- Generating done
-- Build files have been written to: /home/adrian/grpc/examples/cpp/helloworld/build