Google Protobuf Tutorial for Mac and c++

protobuf-tutorial-mac.md

How to Install and Run Google's Protocol Buffer Basics: C++ Tutorial on Mac

Tested on: macOS High Sierra v10.13.3

1. Install Google Protobuf

Google's official README is here. Follow their instructions to install the special dependencies that mac needs.

The steps I share below are a combination of this gist, this gist, and this answer. The main difference is that I started by manually downloading the latest cpp release from google's release repo. If you start from there, here's what to do next:

1. First, unzip the file.

2. Then, Open Terminal and run the following:

Move the downloaded folder into /usr/local/bin

$ sudo mv ~/Downloads/protobuf-3.6.1 /usr/local/bin

Go into that directory

$ cd /usr/local/bin/protobuf-3.6.1

Configure how cmake is going to build protoc

$ ./configure CC=clang CXX="clang++ -std=c++11 -stdlib=libc++" CXXFLAGS="-O3" --disable-shared

Make and Install

$ make 
$ sudo make install

If installed properly, you should see the library version when you run the following:

$ protoc --version
libprotoc 3.6.1

All together it looks like this:

$ sudo mv ~/Downloads/protobuf-3.6.1 /usr/local/bin
$ cd /usr/local/bin/protobuf-3.6.1
$ ./configure CC=clang CXX="clang++ -std=c++11 -stdlib=libc++" CXXFLAGS="-O3" --disable-shared
$ make 
$ sudo make install
$ protoc --version
libprotoc 3.6.1

2. Build the Example Tutorial files

How to run Google's Protocol Buffer Basics: C++ Tutorial

Build the addressbook proto:

$ cd examples/
$ protoc --cpp_out=. addressbook.proto

You should see two new files , addressbook.pb.h and addressbook.pb.cc, in the examples/ directory.

Build the add_people and list_people executables from the command line:

$ clang++ -std=c++11 -stdlib=libc++ add_people.cc addressbook.pb.cc -L/usr/local/lib -lprotobuf -o add_people_cpp

$ clang++ -std=c++11 -stdlib=libc++ list_people.cc addressbook.pb.cc -L/usr/local/lib -lprotobuf -o list_people_cpp

3. Run the Executables

Once everthing is linked and built properly, you can run the apps:

Start the add_people app:

$ ./add_people_cpp addressbook.data

Follow the command prompts

Start the list_people app:

$ ./list_people_cpp addressbook.data

You should see all your entries added from add_people_cpp

Thanks for your great help! Stuck on C++ part for quite a while.

Tested on macOS Big Sur 11.5.2

Works, even though could not resolve protobuf config file, as I installed protobuf using brew so there was no cmake install. This did not appear to impact protobuf compilation or the program.

Corrections
You need to change the add program name in the README, in my examples folder the file is add_person.cc.

So the compile becomes:
$ clang++ -std=c++11 -stdlib=libc++ add_person.cc addressbook.pb.cc -L/usr/local/lib -lprotobuf -o add_person_cpp

And the executable is invoked as:
$ ./add_person_cpp addressbook.data

The latest release lacks Google's third party unit tests. These are recommended by Google for installations to confirm you have a working protobuf environment (with a warning if any fail all bets are off for anything protobuf).

Here are the steps I followed to add them, and build and test everything. Note the steps are slightly different from the above, and more aligned to the protobuf/src/README.md for C++ installation.

If unit tests fail, or you need to try again, do 'make clean/make uninstall' and start at Configure.

Clone protobuf repo
$ git clone git@github.com:protocolbuffers/protobuf.git /somepath/github-google_protobuf
$ cd /somepath/github-google_protobuf
$ git submodule update --init --recursive

Download latest release, eg:
https://github.com/protocolbuffers/protobuf/releases/download/v3.17.3/protobuf-cpp-3.17.3.zip

Install in /usr/local/bin
$ sudo mv ~/Downloads/protobuf-3.7.13 /usr/local/bin/.

Copy thirdparty tests from local repo
$ cd /usr/local/bin/protobuf-3.7.13/third_party
$ cp -rp /somepath/github-google_protobuf/third_party/* .
$ cd ..

Configure
$ ./autogen.sh
$ ./configure

Build (confirm all tests pass)
$ make
$ make check

Install
$ make install

Confirm
$ protoc --version
libprotoc 3.17.3