Migrate to Emscripten's native Bazel rules. (#132)

Signed-off-by: Piotr Sikora <piotrsikora@google.com>

BUILD

@@ -13,6 +13,7 @@ cc_library(
         "proxy_wasm_api.h",
         "proxy_wasm_externs.h",
     ],
+    copts = ["-std=c++17"],
     deps = [
         ":common_lib",
         "@com_google_protobuf//:protobuf_lite",
@@ -25,6 +26,7 @@ cc_library(
         "proxy_wasm_common.h",
         "proxy_wasm_enums.h",
     ],
+    copts = ["-std=c++17"],
 )
 
 cc_library(
@@ -39,6 +41,7 @@ cc_library(
         "proxy_wasm_externs.h",
         "proxy_wasm_intrinsics.h",
     ],
+    copts = ["-std=c++17"],
     visibility = ["//visibility:public"],
 )
 
@@ -62,7 +65,8 @@ proto_library(
 cc_library(
     name = "proxy_wasm_intrinsics_lite",
     hdrs = ["proxy_wasm_intrinsics_lite.h"],
-    copts = ["-DPROXY_WASM_PROTOBUF_LITE=1"],
+    copts = ["-std=c++17"],
+    defines = ["PROXY_WASM_PROTOBUF_LITE"],
     visibility = ["//visibility:public"],
     deps = [
         ":proxy_wasm_intrinsics",
@@ -75,7 +79,8 @@ cc_library(
 cc_library(
     name = "proxy_wasm_intrinsics_full",
     hdrs = ["proxy_wasm_intrinsics_full.h"],
-    copts = ["-DPROXY_WASM_PROTOBUF_FULL=1"],
+    copts = ["-std=c++17"],
+    defines = ["PROXY_WASM_PROTOBUF_FULL"],
     visibility = ["//visibility:public"],
     deps = [
         ":proxy_wasm_intrinsics",

WORKSPACE

@@ -1,9 +1,13 @@
 workspace(name = "proxy_wasm_cpp_sdk")
 
-load("@proxy_wasm_cpp_sdk//bazel/dep:deps.bzl", "wasm_dependencies")
+load("@proxy_wasm_cpp_sdk//bazel:repositories.bzl", "proxy_wasm_cpp_host_repositories")
 
-wasm_dependencies()
+proxy_wasm_cpp_host_repositories()
 
-load("@proxy_wasm_cpp_sdk//bazel/dep:deps_extra.bzl", "wasm_dependencies_extra")
+load("@proxy_wasm_cpp_sdk//bazel:dependencies.bzl", "proxy_wasm_cpp_host_dependencies")
 
-wasm_dependencies_extra()
+proxy_wasm_cpp_host_dependencies()
+
+load("@proxy_wasm_cpp_sdk//bazel:dependencies_extra.bzl", "proxy_wasm_cpp_host_dependencies_extra")
+
+proxy_wasm_cpp_host_dependencies_extra()

bazel/defs.bzl

@@ -0,0 +1,116 @@
+# Copyright 2022 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+load("@emsdk//emscripten_toolchain:wasm_rules.bzl", "wasm_cc_binary")
+load("@rules_cc//cc:defs.bzl", "cc_binary")
+
+def _optimized_wasm_cc_binary_transition_impl(settings, attr):
+    # TODO(PiotrSikora): Add -flto to copts/linkopts when fixed in emsdk.
+    # See: https://github.com/emscripten-core/emsdk/issues/971
+    return {
+        "//command_line_option:copt": ["-O3"],
+        "//command_line_option:cxxopt": [],
+        "//command_line_option:linkopt": [],
+        "//command_line_option:collect_code_coverage": False,
+    }
+
+_optimized_wasm_cc_binary_transition = transition(
+    implementation = _optimized_wasm_cc_binary_transition_impl,
+    inputs = [],
+    outputs = [
+        "//command_line_option:copt",
+        "//command_line_option:cxxopt",
+        "//command_line_option:linkopt",
+        "//command_line_option:collect_code_coverage",
+    ],
+)
+
+def _optimized_wasm_cc_binary_impl(ctx):
+    input_binary = ctx.attr.wasm_cc_target[0][DefaultInfo].files_to_run.executable
+    input_runfiles = ctx.attr.wasm_cc_target[0][DefaultInfo].default_runfiles
+    copied_binary = ctx.actions.declare_file(ctx.attr.name)
+
+    ctx.actions.run(
+        mnemonic = "CopyFile",
+        executable = "cp",
+        arguments = [input_binary.path, copied_binary.path],
+        inputs = [input_binary],
+        outputs = [copied_binary],
+    )
+
+    return DefaultInfo(
+        executable = copied_binary,
+        runfiles = input_runfiles,
+    )
+
+_optimized_wasm_cc_binary = rule(
+    implementation = _optimized_wasm_cc_binary_impl,
+    attrs = {
+        "wasm_cc_target": attr.label(
+            doc = "The wasm_cc_binary to extract files from.",
+            cfg = _optimized_wasm_cc_binary_transition,
+            mandatory = True,
+        ),
+        "_allowlist_function_transition": attr.label(
+            default = "@bazel_tools//tools/allowlists/function_transition_allowlist",
+        ),
+    },
+    executable = True,
+)
+
+def proxy_wasm_cc_binary(
+        name,
+        additional_linker_inputs = [],
+        linkopts = [],
+        tags = [],
+        deps = [],
+        protobuf = "",
+        **kwargs):
+    proxy_wasm_deps = ["@proxy_wasm_cpp_sdk//:proxy_wasm_intrinsics"]
+    if protobuf == "lite":
+        proxy_wasm_deps.append("@proxy_wasm_cpp_sdk//:proxy_wasm_intrinsics_lite")
+    if protobuf == "full":
+        proxy_wasm_deps.append("@proxy_wasm_cpp_sdk//:proxy_wasm_intrinsics_full")
+
+    cc_binary(
+        name = "proxy_wasm_" + name.rstrip(".wasm"),
+        additional_linker_inputs = additional_linker_inputs + [
+            "@proxy_wasm_cpp_sdk//:proxy_wasm_intrinsics_js",
+        ],
+        linkopts = linkopts + [
+            "--no-entry",
+            "--js-library=$(location @proxy_wasm_cpp_sdk//:proxy_wasm_intrinsics_js)",
+            "-sSTANDALONE_WASM",
+            "-sEXPORTED_FUNCTIONS=_malloc",
+        ],
+        tags = tags + [
+            "manual",
+        ],
+        deps = deps + proxy_wasm_deps,
+        **kwargs
+    )
+
+    wasm_cc_binary(
+        name = "wasm_" + name,
+        cc_target = ":proxy_wasm_" + name.rstrip(".wasm"),
+        tags = tags + [
+            "manual",
+        ],
+    )
+
+    _optimized_wasm_cc_binary(
+        name = name,
+        wasm_cc_target = ":wasm_" + name,
+        tags = tags,
+    )

bazel/dep/deps_extra.bzl → bazel/dependencies.bzl

@@ -13,7 +13,9 @@
 #  limitations under the License.
 
 load("@com_google_protobuf//:protobuf_deps.bzl", "protobuf_deps")
+load("@emsdk//:deps.bzl", emsdk_deps = "deps")
 
-# Wasm deps that rely on a first stage of dependency loading in wasm_dependencies().
-def wasm_dependencies_extra():
+# Requires proxy_wasm_cpp_host_repositories() to be loaded first.
+def proxy_wasm_cpp_host_dependencies():
     protobuf_deps()
+    emsdk_deps()

bazel/dependencies_extra.bzl

@@ -0,0 +1,19 @@
+#  Copyright 2020 Google LLC
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#       http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+
+load("@emsdk//:emscripten_deps.bzl", "emscripten_deps")
+
+# Requires proxy_wasm_cpp_host_dependencies() to be loaded first.
+def proxy_wasm_cpp_host_dependencies_extra():
+    emscripten_deps()

bazel/dep/deps.bzl → bazel/repositories.bzl

@@ -15,18 +15,14 @@
 load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
 load("@bazel_tools//tools/build_defs/repo:utils.bzl", "maybe")
 
-def wasm_dependencies():
+def proxy_wasm_cpp_host_repositories():
     maybe(
         http_archive,
-        name = "emscripten_toolchain",
-        build_file = "@proxy_wasm_cpp_sdk//:emscripten-toolchain.BUILD",
-        patch_cmds = [
-            "./emsdk install 3.1.7",
-            "./emsdk activate --embedded 3.1.7",
-        ],
-        strip_prefix = "emsdk-3.1.7",
-        url = "https://github.com/emscripten-core/emsdk/archive/3.1.7.tar.gz",
-        sha256 = "bcceced0b7cad2e08375adf74ef20fa431230abbae8766bdad268c43e34f8d03",
+        name = "emsdk",
+        sha256 = "1ca0ff918d476c55707bb99bc0452be28ac5fb8f22a9260a8aae8a38d1bc0e27",
+        # v3.1.7 with Bazel fixes
+        strip_prefix = "emsdk-0ea8f8a8707070e9a7c83fbb4a3065683bcf1799/bazel",
+        url = "https://github.com/emscripten-core/emsdk/archive/0ea8f8a8707070e9a7c83fbb4a3065683bcf1799.tar.gz",
     )
 
     maybe(

bazel/wasm/wasm.bzl

@@ -13,92 +13,8 @@
 #  See the License for the specific language governing permissions and
 #  limitations under the License.
 
-load("@rules_cc//cc:defs.bzl", "cc_binary")
-
-def _wasm_cc_transition_impl(settings, attr):
-    return {
-        "//command_line_option:cpu": "wasm32",
-        "//command_line_option:crosstool_top": "@proxy_wasm_cpp_sdk//toolchain:emscripten",
-
-        # Overriding copt/cxxopt/linkopt to prevent sanitizers/coverage options leak
-        # into Wasm build configuration
-        "//command_line_option:copt": [],
-        "//command_line_option:cxxopt": [],
-        "//command_line_option:linkopt": [],
-        "//command_line_option:collect_code_coverage": "false",
-        "//command_line_option:fission": "no",
-    }
-
-wasm_cc_transition = transition(
-    implementation = _wasm_cc_transition_impl,
-    inputs = [],
-    outputs = [
-        "//command_line_option:cpu",
-        "//command_line_option:crosstool_top",
-        "//command_line_option:copt",
-        "//command_line_option:cxxopt",
-        "//command_line_option:fission",
-        "//command_line_option:linkopt",
-        "//command_line_option:collect_code_coverage",
-    ],
-)
-
-def wasm_binary_impl(ctx):
-    out = ctx.actions.declare_file(ctx.label.name)
-    ctx.actions.run(
-        executable = "cp",
-        arguments = [ctx.files.binary[0].path, out.path],
-        outputs = [out],
-        inputs = ctx.files.binary,
-    )
-
-    return [DefaultInfo(files = depset([out]), runfiles = ctx.runfiles([out]))]
-
-def _wasm_attrs(transition):
-    return {
-        "binary": attr.label(mandatory = True, cfg = transition),
-        "_whitelist_function_transition": attr.label(default = "@bazel_tools//tools/whitelists/function_transition_whitelist"),
-    }
-
-# Wasm binary rule implementation.
-# This copies the binary specified in binary attribute in Wasm configuration to
-# target configuration, so a binary in non-Wasm configuration can depend on them.
-wasm_cc_binary_rule = rule(
-    implementation = wasm_binary_impl,
-    attrs = _wasm_attrs(wasm_cc_transition),
-)
-
 def wasm_cc_binary(**kwargs):
-    fail("`wasm_cc_binary` is deprecated. Please use `proxy_wasm_cc_binary`.")
-
-def proxy_wasm_cc_binary(name, additional_linker_inputs = [], linkopts = [], tags = [], deps = [], **kwargs):
-    wasm_name = "_wasm_" + name
-    kwargs.setdefault("visibility", ["//visibility:public"])
-    cc_binary(
-        name = wasm_name,
-        additional_linker_inputs = additional_linker_inputs + [
-            "@proxy_wasm_cpp_sdk//:proxy_wasm_intrinsics_js",
-        ],
-        linkopts = linkopts + [
-            "--no-entry",
-            "--js-library=$(location @proxy_wasm_cpp_sdk//:proxy_wasm_intrinsics_js)",
-            "-sSTANDALONE_WASM",
-            "-sEXPORTED_FUNCTIONS=_malloc",
-        ],
-        # Adding manual tag it won't be built in non-Wasm (e.g. x86_64 config)
-        # when an wildcard is specified, but it will be built in Wasm configuration
-        # when the wasm_binary below is built.
-        tags = tags + [
-            "manual",
-        ],
-        deps = deps + [
-            "@proxy_wasm_cpp_sdk//:proxy_wasm_intrinsics",
-        ],
-        **kwargs
-    )
+    fail("`wasm_cc_binary` is deprecated. Please use `proxy_wasm_cc_binary` from `@proxy_wasm_cpp_sdk//bazel:defs.bzl`.")
 
-    wasm_cc_binary_rule(
-        name = name,
-        binary = ":" + wasm_name,
-        tags = tags,
-    )
+def proxy_wasm_cc_binary(**kwargs):
+    fail("Please use `proxy_wasm_cc_binary` from `@proxy_wasm_cpp_sdk//bazel:defs.bzl`.")

example/BUILD

@@ -1,8 +1,23 @@
-load("//bazel/wasm:wasm.bzl", "proxy_wasm_cc_binary")
+load("@proxy_wasm_cpp_sdk//bazel:defs.bzl", "proxy_wasm_cc_binary")
 
 licenses(["notice"])  # Apache 2
 
 proxy_wasm_cc_binary(
     name = "http_wasm_example.wasm",
     srcs = ["http_wasm_example.cc"],
+    copts = ["-std=c++17"],
+)
+
+proxy_wasm_cc_binary(
+    name = "http_wasm_example_with_protobuf_lite.wasm",
+    srcs = ["http_wasm_example.cc"],
+    copts = ["-std=c++17"],
+    protobuf = "lite",
+)
+
+proxy_wasm_cc_binary(
+    name = "http_wasm_example_with_protobuf_full.wasm",
+    srcs = ["http_wasm_example.cc"],
+    copts = ["-std=c++17"],
+    protobuf = "full",
 )

example/http_wasm_example.cc

@@ -46,7 +46,17 @@ static RegisterContextFactory register_ExampleContext(CONTEXT_FACTORY(ExampleCon
                                                       "my_root_id");
 
 bool ExampleRootContext::onStart(size_t) {
+#if defined(PROXY_WASM_PROTOBUF_FULL)
+  LOG_TRACE("onStart with protobuf (full)");
+  google::protobuf::Value value;
+  value.set_string_value("unused");
+#elif defined(PROXY_WASM_PROTOBUF_LITE)
+  LOG_TRACE("onStart with protobuf (lite)");
+  google::protobuf::Value value;
+  value.set_string_value("unused");
+#else
   LOG_TRACE("onStart");
+#endif
   return true;
 }