Protobuf is a Common Lisp implementation of Google's protocol buffers, version 2. The repository contains a compiler from protocol buffer source code (.proto files) to Lisp and also run-time support needed by the generated Lisp code.

Protobuf passes all but a couple of the required proto2 tests in Google's conformance test suite. It implements neither the JSON nor text encoding formats.

Protobuf has been tested with ABCL, CCL, CLISP, Lispworks, and SBCL. In the past it has also worked with Allegro Common Lisp, but I have not tested it recently.

The Common Lisp protocol buffer compiler is implemented as a plugin to Google's protocol buffer compiler, so you must first build and install Google's compiler, which is called protoc. The code and instructions here assume you are using release 3.6.1.

The steps for installing protoc from source are approximately:

cd /tmp
git clone https://github.com/protocolbuffers/protobuf.git google-protobuf
cd google-protobuf
git checkout v3.6.1
./autogen.sh
./configure --prefix=~/local/software/package/google-protobuf-3.6.1
make
make check
make install

You can also install protoc by downloading a tar or zip archive for a specific release from here.

After you have installed protoc, clone this Git repository to create a local copy and compile protoc-gen-lisp, the Common Lisp protocol buffer plugin. The required steps for Linux are approximately:

cd /tmp
git clone git://github.com/brown/protobuf.git

cd protobuf/protoc/lisp

# Copy strutil.h from the Google's protocol buffer compiler source
# directory that you downloaded earlier:
cp /tmp/google-protobuf/src/google/protobuf/stubs/strutil.h .

# Change INSTALL_ROOT and PROTOC_ROOT in Makefile.  INSTALL_ROOT indicates
# where protoc-gen-lisp should be installed.  PROTOC_ROOT indicates where
# you installed Google's protobuf compiler, when you compiled it in step 1.

# Compile and install the Lisp protoc plugin.
make install

Once both protoc and protoc-gen-lisp are installed, download and install the Common Lisp packages that Protobuf depends on. First, you'll need ASDF, but it comes pre-installed in most Common Lisp distributions. You'll also need the com.google.base package, which is available via Quicklisp. To run all the tests, you'll need the Stefil testing package and its dependencies: hu.dwim.stefil, hu.dwim.asdf, alexandria. All of these can easily be downloaded using Quicklisp.

If you're not using Allegro, CLISP, or SBCL, you may need trivial-utf8, again available via Quicklisp.

Once you have acquired all Protobuf's dependencies, make them available to ASDF. There are several ways to do this and you should consult the ASDF documentation to determine what will work best for you. If you've downloaded dependencies using Quicklisp, then ASDF automatically knows about them.

ASDF and its manual are available here.

On my system, I tell ASDF where to find Protobuf's system files by creating a file called source-registry.conf in directory /home/brown/.config/common-lisp with the following contents:

(:source-registry
 (:tree "/home/brown/src/protobuf/")
 :inherit-configuration)

Make sure ASDF can execute Google's protocol buffer compiler and the Common Lisp plugin. Both protoc and protoc-gen-lisp must be installed in directories that appear in your shell's PATH environment variable.

Compile and load all the protobuf code:

(asdf:load-system 'protobuf)

Optionally, load and run all the tests:

(asdf:test-system 'varint)
(asdf:test-system 'protobuf)

Compile and run the example code, which shows how to incorporate protocol buffer definition files into your own projects:

(asdf:load-system 'protobuf-example)

(in-package address-book)
(add-person :id 100
            :name "Robert Brown"
            :email-address "[email protected]"
            :phone-numbers '((home . "718-555-1212")
                             (work . "212-589-1212")
                             (mobile . "917-555-1212")))
(list-people)

Please report bugs and send suggestions on GitHub or contact me directly. My email is robert.brown at the mail hosting site gmail.com.