bazel: Migrate from WORKSPACE to bzlmod (nanopb#950)

The bazel build system is migrating to a new way of
defining modules. To support this, nanopb bazel
build rules have been updated.

Co-authored-by: Mark Hill <markleehill@gmail.com>

.bazelignore

@@ -0,0 +1 @@
+tests/bazel_workspace_support

.gitattributes

@@ -0,0 +1,3 @@
+# Auto-generated files that don't need human review.
+MODULE.bazel.lock linguist-generated=true
+extra/requirements_lock.txt linguist-generated=true

.github/workflows/bazel.yml

@@ -15,7 +15,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        os: [ubuntu-20.04, macos-11]
+        os: [ubuntu-20.04, macos-14]
 
     steps:
       - uses: actions/checkout@v2

BUILD.bazel

@@ -1,5 +1,8 @@
 load("@rules_proto//proto:defs.bzl", "proto_library")
-load("@rules_python//python:defs.bzl", "py_binary")
+
+# Note: if you are still using WORKSPACE, you will need to patch this file to use the following instead
+# load("@python_3_11//:defs.bzl", "py_binary")
+load("@python_versions//3.11:defs.bzl", "py_binary")
 load("@nanopb_pypi//:requirements.bzl", "requirement")
 load("@rules_proto_grpc//:defs.bzl", "proto_plugin")
 load("@bazel_skylib//rules:copy_file.bzl", "copy_file")
@@ -82,13 +85,21 @@ proto_library(
     deps = ["@com_google_protobuf//:descriptor_proto"],
 )
 
+py_proto_library(
+    name = "descriptor_py_proto",
+    srcs = [
+        "generator/proto/google/protobuf/descriptor.proto",
+    ],
+    include = "generator/proto",
+)
+
 py_proto_library(
     name = "nanopb_py_proto",
     srcs = [
         "generator/proto/nanopb.proto",
     ],
     include = "generator/proto",
-    deps = ["@com_google_protobuf//:protobuf_python"],
+    deps = [":descriptor_py_proto"],
 )
 
 cc_nanopb_proto_library(

MODULE.bazel

@@ -0,0 +1,38 @@
+module(
+    name = "nanopb",
+    version = "0.4.9",
+)
+
+bazel_dep(name = "bazel_skylib", version = "1.5.0")
+bazel_dep(name = "rules_cc", version = "0.0.9")
+bazel_dep(name = "rules_python", version = "0.31.0")
+bazel_dep(name = "rules_proto", version = "5.3.0-21.7")
+bazel_dep(name = "protobuf", version = "23.1", repo_name = "com_google_protobuf")
+
+pip = use_extension("@rules_python//python/extensions:pip.bzl", "pip")
+
+python = use_extension("@rules_python//python/extensions:python.bzl", "python")
+
+PYTHON_VERSION = "3.11"
+
+# No need for this since rules_python already creates our version.
+# python.toolchain(python_version = PYTHON_VERSION)
+use_repo(python, "python_versions")
+
+use_repo(pip, "nanopb_pypi")
+pip.parse(
+    hub_name = "nanopb_pypi",
+    python_version = PYTHON_VERSION,
+    requirements_lock = "@nanopb//:extra/requirements_lock.txt",
+)
+
+http_archive = use_repo_rule("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
+
+http_archive(
+    name = "rules_proto_grpc",
+    sha256 = "c0d718f4d892c524025504e67a5bfe83360b3a982e654bc71fed7514eb8ac8ad",
+    strip_prefix = "rules_proto_grpc-4.6.0",
+    urls = ["https://github.com/rules-proto-grpc/rules_proto_grpc/archive/4.6.0.tar.gz"],
+)
+
+register_toolchains("@rules_proto_grpc//protobuf:protoc_toolchain")