| # Copyright (c) 2023, Google LLC |
| # All rights reserved. |
| # |
| # Use of this source code is governed by a BSD-style |
| # license that can be found in the LICENSE file or at |
| # https://developers.google.com/open-source/licenses/bsd |
| |
| """lua_proto_library(): a rule for building Lua protos.""" |
| |
| load("@bazel_skylib//lib:paths.bzl", "paths") |
| |
| # Generic support code ######################################################### |
| |
| # begin:github_only |
| _is_google3 = False |
| # end:github_only |
| |
| # begin:google_only |
| # _is_google3 = True |
| # end:google_only |
| |
| def _get_real_short_path(file): |
| # For some reason, files from other archives have short paths that look like: |
| # ../com_google_protobuf/google/protobuf/descriptor.proto |
| short_path = file.short_path |
| if short_path.startswith("../"): |
| second_slash = short_path.index("/", 3) |
| short_path = short_path[second_slash + 1:] |
| |
| # Sometimes it has another few prefixes like: |
| # _virtual_imports/any_proto/google/protobuf/any.proto |
| # benchmarks/_virtual_imports/100_msgs_proto/benchmarks/100_msgs.proto |
| # We want just google/protobuf/any.proto. |
| virtual_imports = "_virtual_imports/" |
| if virtual_imports in short_path: |
| short_path = short_path.split(virtual_imports)[1].split("/", 1)[1] |
| return short_path |
| |
| def _get_real_root(ctx, file): |
| real_short_path = _get_real_short_path(file) |
| root = file.path[:-len(real_short_path) - 1] |
| if not _is_google3 and ctx.rule.attr.strip_import_prefix: |
| root = paths.join(root, ctx.rule.attr.strip_import_prefix[1:]) |
| return root |
| |
| def _generate_output_file(ctx, src, extension): |
| package = ctx.label.package |
| if not _is_google3 and ctx.rule.attr.strip_import_prefix and ctx.rule.attr.strip_import_prefix != "/": |
| package = package[len(ctx.rule.attr.strip_import_prefix):] |
| real_short_path = _get_real_short_path(src) |
| real_short_path = paths.relativize(real_short_path, package) |
| output_filename = paths.replace_extension(real_short_path, extension) |
| ret = ctx.actions.declare_file(output_filename) |
| return ret |
| |
| # upb_proto_library / upb_proto_reflection_library shared code ################# |
| |
| _LuaFilesInfo = provider( |
| "A set of lua files generated from .proto files", |
| fields = ["files"], |
| ) |
| |
| def _compile_upb_protos(ctx, proto_info, proto_sources): |
| files = [_generate_output_file(ctx, name, "_pb.lua") for name in proto_sources] |
| transitive_sets = proto_info.transitive_descriptor_sets.to_list() |
| ctx.actions.run( |
| inputs = depset( |
| direct = [proto_info.direct_descriptor_set], |
| transitive = [proto_info.transitive_descriptor_sets], |
| ), |
| tools = [ctx.executable._upbc], |
| outputs = files, |
| executable = ctx.executable._protoc, |
| arguments = [ |
| "--lua_out=" + _get_real_root(ctx, files[0]), |
| "--plugin=protoc-gen-lua=" + ctx.executable._upbc.path, |
| "--descriptor_set_in=" + ctx.configuration.host_path_separator.join([f.path for f in transitive_sets]), |
| ] + |
| [_get_real_short_path(file) for file in proto_sources], |
| progress_message = "Generating Lua protos for :" + ctx.label.name, |
| ) |
| return files |
| |
| def _lua_proto_rule_impl(ctx): |
| if len(ctx.attr.deps) != 1: |
| fail("only one deps dependency allowed.") |
| dep = ctx.attr.deps[0] |
| if _LuaFilesInfo not in dep: |
| fail("proto_library rule must generate _LuaFilesInfo (aspect should have handled this).") |
| files = dep[_LuaFilesInfo].files |
| return [ |
| DefaultInfo( |
| files = files, |
| data_runfiles = ctx.runfiles(files = files.to_list()), |
| ), |
| ] |
| |
| def _lua_proto_library_aspect_impl(target, ctx): |
| proto_info = target[ProtoInfo] |
| files = _compile_upb_protos(ctx, proto_info, proto_info.direct_sources) |
| deps = ctx.rule.attr.deps |
| transitive = [dep[_LuaFilesInfo].files for dep in deps if _LuaFilesInfo in dep] |
| return [_LuaFilesInfo(files = depset(direct = files, transitive = transitive))] |
| |
| # lua_proto_library() ########################################################## |
| |
| _lua_proto_library_aspect = aspect( |
| attrs = { |
| "_upbc": attr.label( |
| executable = True, |
| cfg = "exec", |
| default = "//lua:protoc-gen-lua", |
| ), |
| "_protoc": attr.label( |
| executable = True, |
| cfg = "exec", |
| default = "//:protoc", |
| ), |
| }, |
| implementation = _lua_proto_library_aspect_impl, |
| provides = [_LuaFilesInfo], |
| attr_aspects = ["deps"], |
| fragments = ["cpp"], |
| ) |
| |
| lua_proto_library = rule( |
| implementation = _lua_proto_rule_impl, |
| attrs = { |
| "deps": attr.label_list( |
| aspects = [_lua_proto_library_aspect], |
| allow_rules = ["proto_library"], |
| providers = [ProtoInfo], |
| ), |
| }, |
| ) |