Allow rules_license metadata in bzlmod

.bazelci/presubmit.yml

@@ -846,6 +846,14 @@ tasks:
     working_directory: examples/bzlmod/hello_world_no_cargo
     build_targets:
       - "//..."
+  bzlmod_rules_license_metadata:
+    name: rules_license_metadata with bzlmod
+    platform: ubuntu2004
+    working_directory: examples/bzlmod/rules_license_metadata
+    build_targets:
+      - "//..."
+    test_targets:
+      - "//..."
   bzlmod_override_targets:
     name: Override Targets bzlmod
     platform: ubuntu2004

crate_universe/extensions.bzl

@@ -25,6 +25,8 @@ _OPT_BOOL_VALUES = {
     "on": True,
 }
 
+GENERATE_RULES_LICENSE_METADATA_ATTR = attr.bool(doc = "Generate rules_license metadata for third party crates", default = False)
+
 def _get_or_insert(d, key, value):
     if key not in d:
         d[key] = value
@@ -78,6 +80,7 @@ def _generate_hub_and_spokes(*, module_ctx, cargo_bazel, cfg, annotations, cargo
 
     rendering_config = json.decode(render_config(
         regen_command = "Run 'cargo update [--workspace]'",
+        generate_rules_license_metadata = cfg.generate_rules_license_metadata,
     ))
     config_file = tag_path.get_child("config.json")
     module_ctx.file(
@@ -512,6 +515,8 @@ _from_cargo = tag_class(
         "generate_build_scripts": CRATES_VENDOR_ATTRS["generate_build_scripts"],
         "splicing_config": CRATES_VENDOR_ATTRS["splicing_config"],
         "supported_platform_triples": CRATES_VENDOR_ATTRS["supported_platform_triples"],
+    } | {
+        "generate_rules_license_metadata": GENERATE_RULES_LICENSE_METADATA_ATTR,
     },
 )
 
@@ -653,6 +658,8 @@ _from_specs = tag_class(
         "generate_build_scripts": CRATES_VENDOR_ATTRS["generate_build_scripts"],
         "splicing_config": CRATES_VENDOR_ATTRS["splicing_config"],
         "supported_platform_triples": CRATES_VENDOR_ATTRS["supported_platform_triples"],
+    } | {
+        "generate_rules_license_metadata": GENERATE_RULES_LICENSE_METADATA_ATTR,
     },
 )
 

examples/bzlmod/rules_license_metadata/.bazelrc

@@ -0,0 +1,12 @@
+# Required on windows
+common --enable_platform_specific_config
+startup --windows_enable_symlinks
+build:windows --enable_runfiles
+
+build --experimental_enable_bzlmod
+
+# This isn't currently the defaut in Bazel, but we enable it to test we'll be ready if/when it flips.
+build --incompatible_disallow_empty_glob
+
+# Required for cargo_build_script support before Bazel 7
+build --incompatible_merge_fixed_and_default_shell_env

examples/bzlmod/rules_license_metadata/.bazelversion

@@ -0,0 +1 @@
+../.bazelversion

examples/bzlmod/rules_license_metadata/.gitignore

@@ -0,0 +1,2 @@
+/bazel-*
+.DS_Store

examples/bzlmod/rules_license_metadata/BUILD.bazel

@@ -0,0 +1,50 @@
+load("@crates//:defs.bzl", "all_crate_deps")
+load("@crates_from_spec//:defs.bzl", all_crate_deps_from_spec = "all_crate_deps")
+load("@rules_license//sample_reports:licenses_used.bzl", "licenses_used")
+load("@rules_python//python:defs.bzl", "py_test")
+load("@rules_rust//rust:defs.bzl", "rust_binary", "rust_doc")
+
+package(default_visibility = ["//visibility:public"])
+
+rust_binary(
+    name = "all_crate_deps",
+    srcs = ["src/main.rs"],
+    deps = all_crate_deps(normal = True),
+)
+
+rust_binary(
+    name = "all_crate_deps_from_spec",
+    srcs = ["src/main.rs"],
+    deps = all_crate_deps_from_spec(normal = True),
+)
+
+rust_doc(
+    name = "all_crate_deps_doc",
+    crate = ":all_crate_deps",
+)
+
+licenses_used(
+    name = "licenses_used",
+    out = "license_info.json",
+    deps = [
+        ":all_crate_deps",
+    ],
+)
+
+licenses_used(
+    name = "licenses_used_from_spec",
+    out = "license_info_from_spec.json",
+    deps = [
+        ":all_crate_deps_from_spec",
+    ],
+)
+
+py_test(
+    name = "license_check_test",
+    srcs = ["license_check_test.py"],
+    data = [
+        ":license_info.json",
+        ":license_info_from_spec.json",
+    ],
+    python_version = "PY3",
+)

examples/bzlmod/rules_license_metadata/Cargo.toml

@@ -0,0 +1,12 @@
+[workspace]
+[package]
+name = "all_crate_deps"
+version = "0.0.0"
+edition = "2021"
+publish = false
+
+[lib]
+path = "fake.rs"
+
+[dependencies]
+anyhow = "1.0.79"

examples/bzlmod/rules_license_metadata/MODULE.bazel

@@ -0,0 +1,54 @@
+"""bazelbuild/rules_rust - bzlmod example"""
+
+module(
+    name = "rules_license_metadata_bzlmod_example",
+    version = "0.0.0",
+)
+
+bazel_dep(name = "platforms", version = "0.0.10")
+bazel_dep(
+    name = "bazel_skylib",
+    version = "1.7.1",
+)
+bazel_dep(name = "rules_python", version = "1.0.0")
+bazel_dep(name = "rules_license", version = "1.0.0")
+bazel_dep(
+    name = "rules_rust",
+    version = "0.0.0",
+)
+local_path_override(
+    module_name = "rules_rust",
+    path = "../../..",
+)
+
+rust = use_extension("@rules_rust//rust:extensions.bzl", "rust")
+rust.toolchain(edition = "2021")
+use_repo(
+    rust,
+    "rust_toolchains",
+)
+
+register_toolchains("@rust_toolchains//:all")
+
+crate = use_extension(
+    "@rules_rust//crate_universe:extensions.bzl",
+    "crate",
+)
+crate.from_cargo(
+    name = "crates",
+    cargo_lockfile = "//:Cargo.lock",
+    generate_rules_license_metadata = True,
+    manifests = ["//:Cargo.toml"],
+)
+use_repo(crate, "crates")
+
+crate_from_spec = use_extension("@rules_rust//crate_universe:extensions.bzl", "crate")
+crate_from_spec.spec(
+    package = "anyhow",
+    version = "1.0.79",
+)
+crate_from_spec.from_specs(
+    name = "crates_from_spec",
+    generate_rules_license_metadata = True,
+)
+use_repo(crate_from_spec, "crates_from_spec")

examples/bzlmod/rules_license_metadata/WORKSPACE.bzlmod

@@ -0,0 +1 @@
+# Intentionally blank; enable strict mode for bzlmod

examples/bzlmod/rules_license_metadata/license_check_test.py

@@ -0,0 +1,60 @@
+import json
+import os
+import codecs
+import unittest
+
+# Largely borrowed from rules_license: 
+# https://github.com/bazelbuild/rules_license/blob/main/examples/vndor/constant_gen/verify_licenses_test.py
+
+APACHE_2_LICENSE_TARGET = "@rules_license~//licenses/spdx:Apache-2.0"
+MIT_LICENSE_TARGET = "@rules_license~//licenses/spdx:MIT"
+
+def load_licenses_info(info_path):
+    """Loads the licenses_info() JSON format."""
+    with codecs.open(info_path, encoding="utf-8") as licenses_file:
+        return json.loads(licenses_file.read())
+
+class LicenseCheckTest(unittest.TestCase):
+    def test_license_info(self):
+        self.check_license("license_info.json", "//:all_crate_deps")
+
+    def test_license_info_from_spec(self):
+        self.check_license("license_info_from_spec.json", "//:all_crate_deps_from_spec")
+
+
+    # Load the generated report and ensure that the data is as expected.
+    # Note: [email protected] is licensed under both Apache-2.0 and MIT, so we expect both to be present
+    # If this dependency is ever changed, you may need to update this test to reflect that
+    def check_license(self, file_name, top_level_target):
+        info = load_licenses_info(os.path.join(os.path.dirname(__file__), file_name))
+        self.assertEqual(len(info),1) 
+        all_crate_deps = info[0]
+        self.assertEqual(all_crate_deps["top_level_target"], top_level_target)
+        self.assertEqual(len(all_crate_deps["dependencies"]), 3)
+
+        licenses = all_crate_deps["licenses"]
+
+        self.assertEqual(len(licenses), 1)
+
+        apache_found = False
+        mit_found = False
+        other_found = False
+        other_license_found = ""
+        for license_item in licenses:
+            for kind in license_item["license_kinds"]:
+                if kind["target"] == APACHE_2_LICENSE_TARGET:
+                    apache_found = True
+                    continue
+                if kind["target"] == MIT_LICENSE_TARGET:
+                    mit_found = True
+                    continue
+                else:
+                    other_found = True
+                    other_license_found = kind["target"]
+                    continue
+        self.assertFalse(other_found, "Unexpected license found: (%s)." % other_license_found)
+        self.assertTrue(apache_found, "Apache-2.0 license not found.")
+        self.assertTrue(mit_found, "MIT license not found.")
+
+if __name__ == "__main__":
+    unittest.main(verbosity=3)

examples/bzlmod/rules_license_metadata/src/main.rs

@@ -0,0 +1,18 @@
+// Copyright 2015 The Bazel Authors. All rights reserved.
+//
+// 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.
+
+fn main() -> anyhow::Result<()> {
+    println!("Hello, world!");
+    Ok(())
+}