atdcpp: new backend

.circleci/setup-system

@@ -25,6 +25,10 @@ sudo apt-get install -y \
 # For JSON Schema and atdpy testing
 pip install jsonschema pytest mypy flake8
 
+# For atdcpp testing
+sudo apt install -y \
+  rapidjson-dev
+
 # To get latest ldc version
 source $(curl https://dlang.org/install.sh | bash -s ldc -a)
 echo "source $(~/dlang/install.sh ldc -a)" >> "$BASH_ENV"

CHANGES.md

@@ -5,6 +5,7 @@ Unreleased
 * atdd: Workaround d compiler bug regarding declaration order when using aliases (#393)
         Algebraic data types (SumType) now uses `alias this` syntax.
 * atdgen: Add support for `<json open_enum>` in Melange (#401)
+* atdcpp: Initial Release
 
 2.15.0 (2023-10-26)
 -------------------

Makefile

@@ -11,6 +11,7 @@ DUNE ?= dune
 all:
 	$(MAKE) -C atdpy clean-for-dune
 	$(MAKE) -C atdd clean-for-dune
+	$(MAKE) -C atdcpp clean-for-dune
 	$(MAKE) -C atdts clean-for-dune
 	$(DUNE) build
 
@@ -50,6 +51,7 @@ test:
 	$(MAKE) test-python
 	$(MAKE) test-ts
 	$(MAKE) test-d
+	$(MAKE) test-cpp
 
 
 # Test the OCaml code used by all the backends
@@ -94,6 +96,11 @@ test-d:
 	$(MAKE) test-common
 	$(MAKE) -C atdd test
 
+.PHONY: test-cpp
+test-cpp:
+	$(MAKE) test-common
+	$(MAKE) -C atdcpp test
+
 ############################################################################
 
 .PHONY: js

README.md

@@ -8,6 +8,7 @@ cross-language data types. It is used as input to generate efficient
 and type-safe serializers, deserializers and validators.
 
 Target programming languages currently supported:
+* C++: [atdcpp](atdcpp)
 * DLang: [atdd](atdd)
 * Java: [atdj](atdj)
 * OCaml, Melange: [atdgen](atdgen)

atdcpp.opam

@@ -0,0 +1,84 @@
+# This file is generated by dune, edit dune-project instead
+opam-version: "2.0"
+synopsis: "C++ code generation for ATD APIs"
+description: "C++ code generation for ATD APIs"
+maintainer: [
+  "Louis Roché <louis@louisroche.net>"
+  "Martin Jambon <martin@mjambon.com>"
+  "Rudi Grinberg <me@rgrinberg.com>"
+]
+authors: [
+  "Martin Jambon <martin@mjambon.com>"
+  "Rudi Grinberg <rudi.grinberg@gmail.com>"
+  "Martin Jambon <martin@r2c.dev>"
+  "Martin Jambon <github@mjambon.com>"
+  "Ivan Jager <aij+git@mrph.org>"
+  "oleksiy <oleksiy.golovko@ahrefs.com>"
+  "David Sheets <sheets@alum.mit.edu>"
+  "Rudi Grinberg <me@rgrinberg.com>"
+  "Martin Jambon <martin@esper.com>"
+  "Jeff Meister <nanaki@gmail.com>"
+  "Caio Wakamatsu <caio.wakamatsu@ahrefs.com>"
+  "Carmelo Piccione <carmelo.piccione@gmail.com>"
+  "Daniel Weil <danweil68@gmail.com>"
+  "Egor Chemokhonenko <egor.chemohonenko@ahrefs.com>"
+  "Gabriel Scherer <gabriel.scherer@gmail.com>"
+  "Raman Varabets <roman.vorobets@gmail.com>"
+  "tzm <frank@boldsolutions.de>"
+  "Mathieu Baudet <mathieubaudet@fb.com>"
+  "Oleksiy Golovko <alexei.golovko@gmail.com>"
+  "Rauan Mayemir <rauan@mayemir.io>"
+  "Carmelo Piccione <cep1@solvuu.com>"
+  "John Billings <john@monkeynut.org>"
+  "Louis Roché <louis@louisroche.net>"
+  "Brendan Long <self@brendanlong.com>"
+  "Chris Yocum <cyocum@gmail.com>"
+  "Louis Roché (Ahrefs) <louis.roche@ahrefs.com>"
+  "Louis Roché <louis.roche@ahrefs.com>"
+  "Pavel Antoshkin <pavel.antoshkin@ahrefs.com>"
+  "Pierre Boutillier <pierre.boutillier@laposte.net>"
+  "Shon Feder <shon.feder@key.me>"
+  "Anurag Soni <anuragsoni.13@gmail.com>"
+  "Arjun Ravi Narayan <arjunravinarayan@gmail.com>"
+  "Asya-kawai <kawai-toshiki@aintek.xyz>"
+  "Christophe Troestler <christophe.Troestler@umons.ac.be>"
+  "Damien Doligez <ddoligez@janestreet.com>"
+  "Daniel M <dan.mntg@gmail.com>"
+  "Ding Xiang Fei <dingxiangfei2009@protonmail.ch>"
+  "François Pottier <francois.pottier@inria.fr>"
+  "Javier Chavarri <javier.chavarri@gmail.com>"
+  "Kate <kit.ty.kate@disroot.org>"
+  "Louis <louis.roche@ahrefs.com>"
+  "Louis Roché <louis@cryptosense.com>"
+  "Raman Varabets <raman+git@ahrefs.com>"
+  "Stephane Legrand <slegrand45@gmail.com>"
+  "Vincent Bernardoff <vb@luminar.eu.org>"
+  "haoyang <haoyang@esper.co>"
+  "pmundkur <prashanth.mundkur@gmail.com>"
+  "ygrek <ygrek@autistici.org>"
+]
+license: "MIT"
+homepage: "https://github.com/ahrefs/atd"
+bug-reports: "https://github.com/ahrefs/atd/issues"
+depends: [
+  "dune" {>= "2.8"}
+  "ocaml" {>= "4.08"}
+  "atd" {>= "2.11.0"}
+  "cmdliner" {>= "1.1.0"}
+  "re"
+  "odoc" {with-doc}
+]
+dev-repo: "git+https://github.com/ahrefs/atd.git"
+build: [
+  ["dune" "subst"] {dev}
+  [
+    "dune"
+    "build"
+    "-p"
+    name
+    "-j"
+    jobs
+    "@install"
+    "@doc" {with-doc}
+  ]
+]

atdcpp/.gitignore

@@ -0,0 +1 @@
+/bin

atdcpp/Makefile

@@ -0,0 +1,36 @@
+#
+# Dlang/JSON backend
+#
+
+DUNE ?= dune
+
+.PHONY: build
+build:
+	rm -f bin/atdcpp
+	$(MAKE) clean-for-dune
+	$(DUNE) build @all
+	mkdir -p bin
+	ln -s ../../_build/install/default/bin/atdcpp bin/atdcpp
+
+# The symlink facilitates the development of test code that depends on the
+# generated code.
+.PHONY: test
+test:
+	$(MAKE) clean-for-dune
+	$(DUNE) runtest -f; status=$$?; \
+	  ln -s ../../../_build/default/atdcpp/test/cpp-tests/everything_atd.hpp \
+	    test/cpp-tests/everything_atd.hpp && \
+	  ln -s ../../../_build/default/atdcpp/test/cpp-tests/everything_atd.cpp \
+	    test/cpp-tests/everything_atd.cpp && \
+	  exit "$$status"
+
+.PHONY: clean-for-dune
+clean-for-dune:
+	rm -f test/cpp-tests/everything_atd.hpp
+	rm -f test/cpp-tests/everything_atd.cpp
+
+.PHONY: clean
+clean:
+	$(MAKE) clean-for-dune
+	$(DUNE) clean
+	rm -rf bin

atdcpp/README.md

@@ -0,0 +1,50 @@
+atdcpp
+==
+
+atdcpp takes type definitions in the ATD format and derives `C++`
+classes that can read and write JSON data. This saves the developer the
+labor writing boilerplate that converts between dicts and classes.
+
+This allows safe interoperability with other languages supported by
+ATD such as OCaml, Java, Python or Scala.
+
+See the sample input type definitions
+[everything.atd](test/atd-input/everything.atd) and
+the C++ output [everything.hpp](test/cpp-expected/everything.hpp).
+
+This implementation makes use of the RapidJson C++ library.
+
+Requirements
+--
+
+Requirements for building and testing `atdcpp`:
+* Opam and dependencies installed from the [`atd` project root](..)
+  with `make setup`.
+* gcc / clang
+* librapidjson
+
+Requirements for generating C++ code:
+* the `atdcpp` executable
+
+Requirements for compiling the generated C++ code:
+* A working C++ compiler (gcc / clang)
+* The rapidjson library
+
+Documentation
+--
+
+* TODO
+
+Development notes
+--
+
+Build or rebuild with `make`. Test with `make test`.
+
+Running the tests is done from the `atdcpp/` main folder with `make
+test`.
+
+We have two kinds of tests for atdcpp:
+* code generation and C++ tests:
+  * they generate C++ code from ATD files and compare the C++ output
+    against the [expectations](cpp-expected).
+  * the generated code is executed by some tests.

atdcpp/src/bin/Atdcpp_main.ml

@@ -0,0 +1,134 @@
+(*
+   Entry point to the Atdcpp command.
+*)
+
+open Printf
+open Cmdliner
+
+type conf = {
+  input_files: string list;
+  version: bool;
+}
+
+let run conf =
+  if conf.version then (
+    print_endline Atdcpp.Version.version;
+    exit 0
+  )
+  else
+    conf.input_files
+    |> List.iter (fun atd_file ->
+      Atdcpp.Codegen.run_file atd_file
+    )
+
+(***************************************************************************)
+(* Command-line processing *)
+(***************************************************************************)
+
+let error msg =
+  eprintf "Error: %s\n%!" msg;
+  exit 1
+
+let input_files_term =
+  let info =
+    Arg.info []  (* list must be empty for anonymous arguments *)
+      ~docv:"PATH"
+      ~doc:"Input file in the ATD format with the '.atd' extension"
+  in
+  let default = [] in
+  Arg.value (Arg.pos_all Arg.file default info)
+
+let version_term =
+  let info =
+    Arg.info ["version"]
+      ~doc:"Prints the version of Atdcpp and exits"
+  in
+  Arg.value (Arg.flag info)
+
+let doc =
+  "Type-safe JSON serializers for D"
+
+(*
+   The structure of the help page.
+*)
+let man = [
+  (* 'NAME' and 'SYNOPSIS' sections are inserted here by cmdliner. *)
+
+  `S Manpage.s_description;  (* standard 'DESCRIPTION' section *)
+  `P "Atdcpp turns a file containing type definitions into D classes \
+      that read, write, and validate JSON data. The generated code \
+      can be type-checked statically upon compilation to ensure user code agrees \
+      with the ATD interface.";
+
+  (* 'ARGUMENTS' and 'OPTIONS' sections are inserted here by cmdliner. *)
+
+  `S Manpage.s_examples; (* standard 'EXAMPLES' section *)
+  `P "The following is a sample ATD file. 'sample.atd' becomes 'sample.d' \
+      with the command 'Atdcpp sample.atd'.";
+  `Pre "\
+(* Sample ATD file sample.atd *)
+
+type foo = {
+  name: string;                 (* required field *)
+  ?description: string option;  (* optional field *)
+  ~tags: string list;           (* optional with implicit default *)
+  ~price <cpp default=\"0.99\">: float;  (* explicit default *)
+  items: bar list;
+}
+
+(* sum type *)
+type bar = [
+  | Thing <json name=\"thing\"> of int
+  | Nothing <json name=\"nothing\">
+]
+";
+
+  `S Manpage.s_authors;
+  `P "Martin Jambon <martin@r2c.dev>";
+
+  `S Manpage.s_bugs;
+  `P "Report issues at https://github.com/ahrefs/atd";
+
+  `S Manpage.s_see_also;
+  `P "atdgen, atdj, atds, atdts"
+]
+
+let cmdline_term run =
+  let combine input_files version =
+    run {
+      input_files;
+      version;
+    }
+  in
+  Term.(const combine
+        $ input_files_term
+        $ version_term
+       )
+
+let parse_command_line_and_run run =
+  let info =
+    Cmd.info
+      ~doc
+      ~man
+      "Atdcpp"
+  in
+  Cmd.v info (cmdline_term run) |> Cmd.eval |> exit
+
+let safe_run conf =
+  try run conf
+  with
+  (* for other exceptions, we show a backtrace *)
+  | Failure msg -> error msg
+  | Atd.Ast.Atd_error msg -> error msg
+  | e ->
+      let trace = Printexc.get_backtrace () in
+      eprintf "Error: exception %s\n%s%!"
+        (Printexc.to_string e)
+        trace
+
+let main () =
+  Printexc.record_backtrace true;
+  let conf = parse_command_line_and_run safe_run in
+  safe_run conf
+
+let () = main ()

atdcpp/src/bin/dune

@@ -0,0 +1,10 @@
+(executable
+ (name atdcpp_main)
+ (public_name atdcpp)
+ (package atdcpp)
+ (libraries
+   cmdliner
+   atdcpp
+   atd
+ )
+)