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Diffstat (limited to 'rules/gather_metadata.bzl')
| -rw-r--r-- | rules/gather_metadata.bzl | 309 |
1 files changed, 309 insertions, 0 deletions
diff --git a/rules/gather_metadata.bzl b/rules/gather_metadata.bzl new file mode 100644 index 0000000..162ea97 --- /dev/null +++ b/rules/gather_metadata.bzl @@ -0,0 +1,309 @@ +# 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 +# +# https://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. +"""Rules and macros for collecting LicenseInfo providers.""" + +load( + "@rules_license//rules:licenses_core.bzl", + "TraceInfo", + "gather_metadata_info_common", + "should_traverse", +) +load( + "@rules_license//rules:providers.bzl", + "ExperimentalMetadataInfo", + "PackageInfo", +) +load( + "@rules_license//rules/private:gathering_providers.bzl", + "TransitiveMetadataInfo", +) + +# Definition for compliance namespace, used for filtering licenses +# based on the namespace to which they belong. +NAMESPACES = ["compliance"] + +def _strip_null_repo(label): + """Removes the null repo name (e.g. @//) from a string. + + The is to make str(label) compatible between bazel 5.x and 6.x + """ + s = str(label) + if s.startswith('@//'): + return s[1:] + elif s.startswith('@@//'): + return s[2:] + return s + +def _bazel_package(label): + clean_label = _strip_null_repo(label) + return clean_label[0:-(len(label.name) + 1)] + +def _gather_metadata_info_impl(target, ctx): + return gather_metadata_info_common( + target, + ctx, + TransitiveMetadataInfo, + NAMESPACES, + [ExperimentalMetadataInfo, PackageInfo], + should_traverse) + +gather_metadata_info = aspect( + doc = """Collects LicenseInfo providers into a single TransitiveMetadataInfo provider.""", + implementation = _gather_metadata_info_impl, + attr_aspects = ["*"], + attrs = { + "_trace": attr.label(default = "@rules_license//rules:trace_target"), + }, + provides = [TransitiveMetadataInfo], + apply_to_generating_rules = True, +) + +def _write_metadata_info_impl(target, ctx): + """Write transitive license info into a JSON file + + Args: + target: The target of the aspect. + ctx: The aspect evaluation context. + + Returns: + OutputGroupInfo + """ + + if not TransitiveMetadataInfo in target: + return [OutputGroupInfo(licenses = depset())] + info = target[TransitiveMetadataInfo] + outs = [] + + # If the result doesn't contain licenses, we simply return the provider + if not hasattr(info, "target_under_license"): + return [OutputGroupInfo(licenses = depset())] + + # Write the output file for the target + name = "%s_metadata_info.json" % ctx.label.name + content = "[\n%s\n]\n" % ",\n".join(metadata_info_to_json(info)) + out = ctx.actions.declare_file(name) + ctx.actions.write( + output = out, + content = content, + ) + outs.append(out) + + if ctx.attr._trace[TraceInfo].trace: + trace = ctx.actions.declare_file("%s_trace_info.json" % ctx.label.name) + ctx.actions.write(output = trace, content = "\n".join(info.traces)) + outs.append(trace) + + return [OutputGroupInfo(licenses = depset(outs))] + +gather_metadata_info_and_write = aspect( + doc = """Collects TransitiveMetadataInfo providers and writes JSON representation to a file. + + Usage: + bazel build //some:target \ + --aspects=@rules_license//rules:gather_metadata_info.bzl%gather_metadata_info_and_write + --output_groups=licenses + """, + implementation = _write_metadata_info_impl, + attr_aspects = ["*"], + attrs = { + "_trace": attr.label(default = "@rules_license//rules:trace_target"), + }, + provides = [OutputGroupInfo], + requires = [gather_metadata_info], + apply_to_generating_rules = True, +) + +def write_metadata_info(ctx, deps, json_out): + """Writes TransitiveMetadataInfo providers for a set of targets as JSON. + + TODO(aiuto): Document JSON schema. But it is under development, so the current + best place to look is at tests/hello_licenses.golden. + + Usage: + write_metadata_info must be called from a rule implementation, where the + rule has run the gather_metadata_info aspect on its deps to + collect the transitive closure of LicenseInfo providers into a + LicenseInfo provider. + + foo = rule( + implementation = _foo_impl, + attrs = { + "deps": attr.label_list(aspects = [gather_metadata_info]) + } + ) + + def _foo_impl(ctx): + ... + out = ctx.actions.declare_file("%s_licenses.json" % ctx.label.name) + write_metadata_info(ctx, ctx.attr.deps, metadata_file) + + Args: + ctx: context of the caller + deps: a list of deps which should have TransitiveMetadataInfo providers. + This requires that you have run the gather_metadata_info + aspect over them + json_out: output handle to write the JSON info + """ + licenses = [] + for dep in deps: + if TransitiveMetadataInfo in dep: + licenses.extend(metadata_info_to_json(dep[TransitiveMetadataInfo])) + ctx.actions.write( + output = json_out, + content = "[\n%s\n]\n" % ",\n".join(licenses), + ) + +def metadata_info_to_json(metadata_info): + """Render a single LicenseInfo provider to JSON + + Args: + metadata_info: A LicenseInfo. + + Returns: + [(str)] list of LicenseInfo values rendered as JSON. + """ + + main_template = """ {{ + "top_level_target": "{top_level_target}", + "dependencies": [{dependencies} + ], + "licenses": [{licenses} + ], + "packages": [{packages} + ]\n }}""" + + dep_template = """ + {{ + "target_under_license": "{target_under_license}", + "licenses": [ + {licenses} + ] + }}""" + + license_template = """ + {{ + "label": "{label}", + "bazel_package": "{bazel_package}", + "license_kinds": [{kinds} + ], + "copyright_notice": "{copyright_notice}", + "package_name": "{package_name}", + "package_url": "{package_url}", + "package_version": "{package_version}", + "license_text": "{license_text}", + "used_by": [ + {used_by} + ] + }}""" + + kind_template = """ + {{ + "target": "{kind_path}", + "name": "{kind_name}", + "conditions": {kind_conditions} + }}""" + + package_info_template = """ + {{ + "target": "{label}", + "bazel_package": "{bazel_package}", + "package_name": "{package_name}", + "package_url": "{package_url}", + "package_version": "{package_version}" + }}""" + + # Build reverse map of license to user + used_by = {} + for dep in metadata_info.deps.to_list(): + # Undo the concatenation applied when stored in the provider. + dep_licenses = dep.licenses.split(",") + for license in dep_licenses: + if license not in used_by: + used_by[license] = [] + used_by[license].append(_strip_null_repo(dep.target_under_license)) + + all_licenses = [] + for license in sorted(metadata_info.licenses.to_list(), key = lambda x: x.label): + kinds = [] + for kind in sorted(license.license_kinds, key = lambda x: x.name): + kinds.append(kind_template.format( + kind_name = kind.name, + kind_path = kind.label, + kind_conditions = kind.conditions, + )) + + if license.license_text: + # Special handling for synthetic LicenseInfo + text_path = (license.license_text.package + "/" + license.license_text.name if type(license.license_text) == "Label" else license.license_text.path) + all_licenses.append(license_template.format( + copyright_notice = license.copyright_notice, + kinds = ",".join(kinds), + license_text = text_path, + package_name = license.package_name, + package_url = license.package_url, + package_version = license.package_version, + label = _strip_null_repo(license.label), + bazel_package = _bazel_package(license.label), + used_by = ",\n ".join(sorted(['"%s"' % x for x in used_by[str(license.label)]])), + )) + + all_deps = [] + for dep in sorted(metadata_info.deps.to_list(), key = lambda x: x.target_under_license): + # Undo the concatenation applied when stored in the provider. + dep_licenses = dep.licenses.split(",") + all_deps.append(dep_template.format( + target_under_license = _strip_null_repo(dep.target_under_license), + licenses = ",\n ".join(sorted(['"%s"' % _strip_null_repo(x) for x in dep_licenses])), + )) + + all_packages = [] + # We would use this if we had distinct depsets for every provider type. + #for package in sorted(metadata_info.package_info.to_list(), key = lambda x: x.label): + # all_packages.append(package_info_template.format( + # label = _strip_null_repo(package.label), + # package_name = package.package_name, + # package_url = package.package_url, + # package_version = package.package_version, + # )) + + for mi in sorted(metadata_info.other_metadata.to_list(), key = lambda x: x.label): + # Maybe use a map of provider class to formatter. A generic dict->json function + # in starlark would help + + # This format is for using distinct providers. I like the compile time safety. + if mi.type == "package_info": + all_packages.append(package_info_template.format( + label = _strip_null_repo(mi.label), + bazel_package = _bazel_package(mi.label), + package_name = mi.package_name, + package_url = mi.package_url, + package_version = mi.package_version, + )) + # experimental: Support the ExperimentalMetadataInfo bag of data + if mi.type == "package_info_alt": + all_packages.append(package_info_template.format( + label = _strip_null_repo(mi.label), + bazel_package = _bazel_package(mi.label), + # data is just a bag, so we need to use get() or "" + package_name = mi.data.get("package_name") or "", + package_url = mi.data.get("package_url") or "", + package_version = mi.data.get("package_version") or "", + )) + + return [main_template.format( + top_level_target = _strip_null_repo(metadata_info.target_under_license), + dependencies = ",".join(all_deps), + licenses = ",".join(all_licenses), + packages = ",".join(all_packages), + )] |