Other Languages

While the current release includes compilers and APIs for C++, Java, Go, Ruby, C#, and Python, the compiler code is designed so that it’s easy to add support for other languages. There are several ongoing projects to add new language implementations to Protocol Buffers, including C, Haskell, Perl, Rust, and more.

For a list of links to projects we know about, see the third-party add-ons wiki page.

Compiler Plugins

protoc, the Protocol Buffers Compiler, can be extended to support new languages via plugins. A plugin is just a program which reads a CodeGeneratorRequest protocol buffer from standard input and then writes a CodeGeneratorResponse protocol buffer to standard output. These message types are defined in plugin.proto. We recommend that all third-party code generators be written as plugins, as this allows all generators to provide a consistent interface and share a single parser implementation.

Plugins can be written in any programming language, but Google owned plugins are written in C++. If you are writing your own plugin you may find it easiest to use C++ for the plugin to be able to follow those examples and reuse utilities.

Additionally, plugins are able to insert code into the files generated by other code generators. See the comments about "insertion points" in plugin.proto for more on this. This could be used, for example, to write a plugin which generates RPC service code that is tailored for a particular RPC system. See the documentation for the generated code in each language to find out what insertion points they provide.