feat(v2): handle modules with replace directive

licenses/library.go

@@ -36,7 +36,7 @@ type Library struct {
 	// It may not be the complete set of all packages in the library.
 	Packages []string
 	// Parent go module.
-	Module *packages.Module
+	module *Module
 }
 
 // PackagesError aggregates all Packages[].Errors into a single error.
@@ -118,7 +118,7 @@ func Libraries(ctx context.Context, classifier Classifier, importPaths ...string
 			for _, p := range pkgs {
 				libraries = append(libraries, &Library{
 					Packages: []string{p.PkgPath},
-					Module:   p.Module,
+					module:   newModule(p.Module),
 				})
 			}
 			continue
@@ -128,15 +128,15 @@ func Libraries(ctx context.Context, classifier Classifier, importPaths ...string
 		}
 		for _, pkg := range pkgs {
 			lib.Packages = append(lib.Packages, pkg.PkgPath)
-			if lib.Module == nil {
+			if lib.module == nil {
 				// All the sub packages should belong to the same module.
-				lib.Module = pkg.Module
+				lib.module = newModule(pkg.Module)
 			}
-			if lib.Module != nil && lib.Module.Path != "" && lib.Module.Dir == "" {
+			if lib.module != nil && lib.module.Path != "" && lib.module.Dir == "" {
 				// A known cause is that the module is vendored, so some information is lost.
 				splits := strings.SplitN(lib.LicensePath, "/vendor/", 2)
 				if len(splits) != 2 {
-					glog.Warningf("module %s does not have dir and it's not vendored, cannot discover the license URL. Report to go-licenses developer if you see this.", lib.Module.Path)
+					glog.Warningf("module %s does not have dir and it's not vendored, cannot discover the license URL. Report to go-licenses developer if you see this.", lib.module.Path)
 				} else {
 					// This is vendored. Handle this known special case.
 					parentModDir := splits[0]
@@ -148,11 +148,11 @@ func Libraries(ctx context.Context, classifier Classifier, importPaths ...string
 						}
 					}
 					if parentPkg == nil {
-						glog.Warningf("cannot find parent package of vendored module %s", lib.Module.Path)
+						glog.Warningf("cannot find parent package of vendored module %s", lib.module.Path)
 					} else {
 						// Vendored modules should be commited in the parent module, so it counts as part of the
 						// parent module.
-						lib.Module = parentPkg.Module
+						lib.module = newModule(parentPkg.Module)
 					}
 				}
 			}
@@ -205,7 +205,7 @@ func (l *Library) FileURL(ctx context.Context, filePath string) (string, error)
 	wrap := func(err error) error {
 		return fmt.Errorf("getting file URL in library %s: %w", l.Name(), err)
 	}
-	m := l.Module
+	m := l.module
 	if m == nil {
 		return "", wrap(fmt.Errorf("empty go module info"))
 	}

licenses/library_test.go

@@ -21,7 +21,6 @@ import (
 
 	"github.com/google/go-cmp/cmp"
 	"github.com/google/go-cmp/cmp/cmpopts"
-	"golang.org/x/tools/go/packages"
 )
 
 func TestLibraries(t *testing.T) {
@@ -155,7 +154,7 @@ func TestLibraryFileURL(t *testing.T) {
 					"github.com/google/trillian/crypto",
 				},
 				LicensePath: "/go/src/github.com/google/trillian/LICENSE",
-				Module: &packages.Module{
+				module: &Module{
 					Path:    "github.com/google/trillian",
 					Dir:     "/go/src/github.com/google/trillian",
 					Version: "v1.2.3",
@@ -172,7 +171,7 @@ func TestLibraryFileURL(t *testing.T) {
 					"bitbucket.org/user/project/pkg2",
 				},
 				LicensePath: "/foo/bar/bitbucket.org/user/project/LICENSE",
-				Module: &packages.Module{
+				module: &Module{
 					Path:    "bitbucket.org/user/project",
 					Dir:     "/foo/bar/bitbucket.org/user/project",
 					Version: "v1.2.3",
@@ -189,7 +188,7 @@ func TestLibraryFileURL(t *testing.T) {
 					"example.com/user/project/pkg2",
 				},
 				LicensePath: "/foo/bar/example.com/user/project/LICENSE",
-				Module: &packages.Module{
+				module: &Module{
 					Path:    "example.com/user/project",
 					Dir:     "/foo/bar/example.com/user/project",
 					Version: "v1.2.3",
@@ -206,7 +205,7 @@ func TestLibraryFileURL(t *testing.T) {
 					"github.com/google/trillian/crypto",
 				},
 				LicensePath: "/go/src/github.com/google/trillian/LICENSE",
-				Module: &packages.Module{
+				module: &Module{
 					Path: "github.com/google/trillian",
 					Dir:  "/go/src/github.com/google/trillian",
 				},
@@ -221,7 +220,7 @@ func TestLibraryFileURL(t *testing.T) {
 					"k8s.io/api/core/v1",
 				},
 				LicensePath: "/go/modcache/k8s.io/api/LICENSE",
-				Module: &packages.Module{
+				module: &Module{
 					Path:    "k8s.io/api",
 					Dir:     "/go/modcache/k8s.io/api",
 					Version: "v0.23.1",

licenses/module.go

@@ -0,0 +1,69 @@
+// Copyright 2022 Inc. 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.
+
+package licenses
+
+import (
+	"strings"
+
+	"golang.org/x/tools/go/packages"
+)
+
+// Module provides module information for a package.
+type Module struct {
+	// Differences from packages.Module:
+	// * Replace field is removed, it's only an implementation detail in this package.
+	//   If a module is replaced, we'll directly return the replaced module.
+	// * Version field +incompatible suffix is trimmed.
+	// * Main, ModuleError, Time, Indirect, GoMod, GoVersion fields are removed, because they are not used.
+	Path    string // module path
+	Version string // module version
+	Dir     string // directory holding files for this module, if any
+}
+
+func newModule(mod *packages.Module) *Module {
+	if mod == nil {
+		return nil
+	}
+	// Example of a module with replace directive: 	k8s.io/kubernetes => k8s.io/kubernetes v1.11.1
+	// {
+	//         "Path": "k8s.io/kubernetes",
+	//         "Version": "v0.17.9",
+	//         "Replace": {
+	//                 "Path": "k8s.io/kubernetes",
+	//                 "Version": "v1.11.1",
+	//                 "Time": "2018-07-17T04:20:29Z",
+	//                 "Dir": "/home/gongyuan_kubeflow_org/go/pkg/mod/k8s.io/[email protected]",
+	//                 "GoMod": "/home/gongyuan_kubeflow_org/go/pkg/mod/cache/download/k8s.io/kubernetes/@v/v1.11.1.mod"
+	//         },
+	//         "Dir": "/home/gongyuan_kubeflow_org/go/pkg/mod/k8s.io/[email protected]",
+	//         "GoMod": "/home/gongyuan_kubeflow_org/go/pkg/mod/cache/download/k8s.io/kubernetes/@v/v1.11.1.mod"
+	// }
+	// handle replace directives
+	// Note, we specifically want to replace version field.
+	// Haven't confirmed, but we may also need to override the
+	// entire struct when using replace directive with local folders.
+	tmp := *mod
+	if tmp.Replace != nil {
+		tmp = *tmp.Replace
+	}
+	// The +incompatible suffix does not affect module version.
+	// ref: https://golang.org/ref/mod#incompatible-versions
+	tmp.Version = strings.TrimSuffix(tmp.Version, "+incompatible")
+	return &Module{
+		Path:    tmp.Path,
+		Version: tmp.Version,
+		Dir:     tmp.Dir,
+	}
+}

testdata/modules/replace04/licenses.csv

@@ -1,2 +1,2 @@
 github.com/google/go-licenses/testdata/modules/replace04, https://github.com/google/go-licenses/blob/HEAD/testdata/modules/replace04/LICENSE, Apache-2.0
-github.com/mitchellh/go-homedir, https://github.com/mitchellh/go-homedir/blob/v1.1.0/LICENSE, MIT
+github.com/mitchellh/go-homedir, https://github.com/mitchellh/go-homedir/blob/v1.0.0/LICENSE, MIT