[SOLVED] How to write a bitbake recipe for a gRPC example using cmake

Issue

I am trying to get the gRPC helloworld example to be compiled with a bitbake recipe. The objective being able to call the greeter-client/server from the embedded target. But, when I do a bitbake grpc-helloworld, I get the following error message:

-- Using protobuf 3.11.4 -- Found ZLIB: /home/buildbot/oe-core/build/tmp/work/aarch64-tdx-linux/grpc-helloworld/1.0.0-r0/recipe-sysroot/usr/lib/libz.so (found version "1.2.11") -- Found OpenSSL: /home/buildbot/oe-core/build/tmp/work/aarch64-tdx-linux/grpc-helloworld/1.0.0-r0/recipe-sysroot/usr/lib/libcrypto.so (found version "1.1.1o") CMake Error at recipe-sysroot/usr/lib/cmake/grpc/gRPCTargets.cmake:197 (message):
The imported target "gRPC::grpc_cpp_plugin" references the file "/home/buildbot/oe-core/build/tmp/work/aarch64-tdx-linux/grpc-helloworld/1.0.0-r0/recipe-sysroot/usr/bin/grpc_cpp_plugin"

but this file does not exist. Possible reasons include: * The file was deleted, renamed, or moved to another location. * An install or uninstall procedure did not complete successfully. * The installation package was faulty and contained "/home/buildbot/oe-core/build/tmp/work/aarch64-tdx-linux/grpc-helloworld/1.0.0-r0/recipe-sysroot/usr/lib/cmake/grpc/gRPCTargets.cmake" but not all the files it references.

Call Stack (most recent call first):
recipe-sysroot/usr/lib/cmake/grpc/gRPCConfig.cmake:16 (include)
common.cmake:116 (find_package) CMakeLists.txt:5 (include)

-- Configuring incomplete, errors occurred!

The grpc_cpp_plugin is indeed not in recipe-sysroot. How do I fix that?

File structure for the recipe:

recipes-customer/
  grpc-helloworld_1.0.0.bb
  grpc-helloworld/
    CMakeLists.txt
    common.cmake
    greeter_client.cc
    greeter_server.cc
    helloworld.proto

Other than for the proto file and common.cmake paths, the CMakeLists.txt is the same as in the grpc example (https://github.com/grpc/grpc/blob/master/examples/cpp/helloworld/CMakeLists.txt).

I just changed the common.cmake for finding Protobuf from find_package(Protobuf CONFIG REQUIRED) to find_package(Protobuf REQUIRED), otherwise this error appeared:

CMake Error at common.cmake:103 (find_package): Could not find a package configuration file provided by "Protobuf" with any of the following names:

ProtobufConfig.cmake protobuf-config.cmake

Add the installation prefix of "Protobuf" to CMAKE_PREFIX_PATH or set "Protobuf_DIR" to a directory containing one of the above files. If "Protobuf" provides a separate development package or SDK, be sure it has been installed. Call Stack (most recent call first):
CMakeLists.txt:5 (include)

This is the bitbake recipe so far, grpc-helloworld_1.0.0.bb:

SUMMARY = "gRPC Hello World"
LICENSE = "CLOSED"
DEPENDS += "protobuf grpc"
SRC_URI += "file://CMakeLists.txt file://*.cc file://*.h"
S = "${WORKDIR}"
inherit pkgconfig cmake

Why do these errors happen? Thank you for your help.

Edit: This same problem was unanswered here (Building a Yocto bitbake recipe, which depends on grpc, grpc-native fails saying the the grpc_cpp_plugin does not exist)

Solution

So, the solution is actually very simple: do not use dunfell.

Using kirkstone, what I showed just works (except file://* aka glob which are not supported by kirkstone and the fact that the CMakeLists.txt file from the gRPC examples needs a install(TARGETS greeter_client greeter_server DESTINATION bin) to complete the recipe task).

I had to be on dunfell until my BSP was updated so I was stuck on this for a while ...

Answered By - mmnano50

Answer Checked By - Candace Johnson (WPSolving Volunteer)