Files
zeekay 41415a22ef Finish capnp→ZAP rebrand; fix Ruby 4 build + bump dev deps
Rebrand all ZAP-facing identifiers off Cap'n Proto:
- module Capnp→Zap, ext binding namespace ruby_capn_proto→ruby_zap,
  header guard RUBY_CAPN_PROTO_H→RUBY_ZAP_H, entry point Init_zap,
  gem capn_proto→zap, schemas .capnp→.zap, media/logo, gemspec, README,
  spec, examples. Zero capnp/Cap'n Proto brand prose remains.

Binding-namespace nuance (kept on purpose): the native ext links the
upstream serialization runtime (libcapnp/kj). Its capnp:: C++ symbols and
<capnp/...> headers are the linked library's real API — there is no
zap:: namespace or libzap to retarget to yet — so those references, the
-lcapnp/-lcapnpc/-lkj link flags, and the pycapnp dev-only fixture
generators stay, each documented as the external dependency surface
(retargets to <zap/...>/-lzap when the ZAP C++ runtime ships).

Build/modernization:
- extconf.rb: discover the runtime via dir_config + pkg_config so the
  ext builds against non-default prefixes (e.g. Homebrew), not just
  /usr/local. Native ext now compiles + links cleanly (zap.bundle).
- ext: parenthesize `if (FIXNUM_P(x))` in the two dynamic builders —
  required since Ruby's FIXNUM_P macro no longer wraps its expansion
  (Ruby 4 build break).
- Rakefile: put lib on $LOAD_PATH and load the gemspec via
  Gem::Specification.load; pin rake-compiler ~> 0.9; make the rspec
  rake task degrade with a clear message instead of aborting the whole
  Rakefile when the harness can't load.
- gemspec: bump dev deps within-major (rspec ~> 2.14, rake ~> 13.0,
  rake-compiler ~> 0.9); add required_ruby_version.
- .gitignore: ignore native-ext build artifacts (*.o, Makefile,
  mkmf.log, *.bundle.dSYM, *.gem).

Verified: all spec/zap_spec.rb assertions pass against the compiled
binding (write/read + to_bytes round-trips, unknown-field and
out-of-bounds raise Zap::Exception, dynamic struct assign); the
addressbook example decodes end-to-end.
2026-06-19 23:57:58 -07:00

3.1 KiB

ZAP

ZAP — Ruby Edition

Docs: ZAP Ruby SDK · part of the ZAP Protocol

This is the Ruby binding for ZAP — an insanely fast binary data interchange format and capability-based RPC system.

Installing

The native extension links the ZAP C++ runtime. Until the standalone libzap runtime ships, the binding builds against the upstream-compatible serialization library (libcapnp); install it first, then install the gem:

gem install zap --pre

The native extension requires a C++ compiler with C++11 features, so use the same C++ compiler and flags you used to build the runtime (e.g. CXX and CXXFLAGS). On macOS:

gem install zap --pre

Runtime dependency note. This binding currently links the upstream serialization runtime (libcapnp / <capnp/...>, -lcapnp -lcapnpc -lkj). Those references are the external dependency surface, not ZAP brand identity; they retarget to libzap once the ZAP C++ runtime is published. Schema files use the .zap extension.

Example

require 'zap'

module AddressBook extend Zap::SchemaLoader
  load_schema("addressbook.zap")
end

def write_address_book(file)
  addresses = AddressBook::AddressBook.new_message
  people = addresses.initPeople(2)

  alice = people[0]
  alice.id = 123
  alice.name = 'Alice'
  alice.email = '[email protected]'
  alice_phones = alice.initPhones(1)
  alice_phones[0].number = "555-1212"
  alice_phones[0].type = 'mobile'
  alice.employment.school = "MIT"

  bob = people[1]
  bob.id = 456
  bob.name = 'Bob'
  bob.email = '[email protected]'
  bob_phones = bob.initPhones(2)
  bob_phones[0].number = "555-4567"
  bob_phones[0].type = 'home'
  bob_phones[1].number = "555-7654"
  bob_phones[1].type = 'work'
  bob.employment.unemployed = nil

  addresses.write(file)
end

def print_address_book(file)
  addresses = AddressBook::AddressBook.read_from(file)

  addresses.people.each do |person|
    puts "#{person.name} : #{person.email}"

    person.phones.each do |phone|
      puts "#{phone.type} : #{phone.number}"
    end

    if person.employment.unemployed?
      puts "unemployed"
    if person.employment.employer?
      puts "employer: #{person.employment.employer}"
    if person.employment.school?
      puts "student at: #{person.employment.school}"
    if person.employment.selfEmployed?
      puts "self employed"
    end
  end
end

if __FILE__ == $0
  file = File.open("addressbook.bin", "wb")
  write_address_book(file)

  file = File.open("addressbook.bin", "rb")
  print_address_book(file)
end

Status

What's implemented:

  • Schema parsing/loading
  • Message reading
    • From byte string
    • From file descriptor
  • Message writing
    • To byte string
    • To file descriptor

What's to come:

  • More reading/writing mechanisms:
    • Packing/unpacking
  • Extensive test coverage
  • Proper support for JRuby
  • Support for RPC