Protocol buffers are Google's language-neutral, platform-neutral, extensible mechanism for serializing structured data – think XML, but smaller, faster, and simpler. You define how you want your data to be structured once. This takes the form of a template that describes the data structure. You use this template to encode and decode your data structure into wire-streams that may be sent-to or read-from your peers. The underlying wire stream is platform independent, lossless, and may be used to interwork with a variety of languages and systems regardless of word size or endianness.
This document was produced using PlDoc, with sources found in
protobufs.pl and protobufs_overview.md. There is a simple example
(assuming you've installed swi-prolog-doc) in
/usr/share/swi-prolog/doc/packages/examples/protobufs/interop/addressbook.pl:
protoc -I/usr/share/doc/protobuf-compiler/examples -I/usr/include --swipl_out=/tmp/ \
--plugin=protoc-gen-swipl=/usr/lib/swi-prolog/library/protobufs/protoc-gen-swipl \
/usr/share/swi-prolog/doc/packages/examples/protobufs/interop/addressbook.pl
This generates /tmp/addressbook_pb.pl … you should change the
--swipl-out= specification to be the directory you want (e.g.,
interop).
Note that protoc requires an -I item that encompasses the .proto
file, so this also works:
protoc -I -I/usr/include --swipl_out=/tmp/ \
-I/usr/share/swi-prolog/doc/packages/examples/protobufs/interop \
--plugin=protoc-gen-swipl=/usr/lib/swi-prolog/library/protobufs/protoc-gen-swipl \
addressbook.proto
and, if /usr/lib/swi-prolog/library/protobufs is in your PATH, you can
leave out the --plugin option:
EXPORT PATH=/usr/lib/swi-prolog/library/protobufs:$PATH
protoc -I/usr/share/swi-prolog/doc/packages/examples/protobufs/interop -I/usr/include --swipl_out=/tmp/ addressbook.proto
It’s possible that your installation puts files in a different place; you can find the addressbook example with:
dpkg -L protobuf-compiler | grep addressbook
To test this, run the following:
swipl -g test_write -g test_write -g test_read -t halt addressbook.pl # outputs to addressbook.wire
protoc --decode=tutorial.AddressBook addressbook.proto <addressbook.wire
@see https://developers.google.com/protocol-buffers @author Jeffrey Rosenwald (JeffRose@acm.org), Peter Ludemann (peter.ludemann@gmail.com) @license BSD-2