Add a licenses subcommand that prints the licenses of all dependencies.

.github/workflows/ci.yml

@@ -19,6 +19,8 @@ jobs:
         uses: actions/setup-go@v2
         with:
           go-version: 1.14.7
+      - name: Install Pkger
+        run: go get github.com/markbates/pkger/cmd/pkger
       - name: Build
         uses: goreleaser/goreleaser-action@v2
         with:

.github/workflows/release.yml

@@ -18,6 +18,8 @@ jobs:
         uses: actions/setup-go@v2
         with:
           go-version: 1.14.7
+      - name: Install Pkger
+        run: go get github.com/markbates/pkger/cmd/pkger
       - name: Release
         uses: goreleaser/goreleaser-action@v2
         with:

.gitignore

@@ -1,2 +1,3 @@
 /codeql-action-sync
 /dist/
+/pkged.go

.goreleaser.yml

@@ -1,5 +1,9 @@
 project_name: codeql-action-sync
 
+before:
+  hooks:
+    - pkger
+
 builds:
   - goos: [linux, darwin, windows]
     goarch: [386, amd64, arm64]

cmd/licenses.go

@@ -0,0 +1,14 @@
+package cmd
+
+import (
+	"github.com/github/codeql-action-sync/internal/licenses"
+	"github.com/spf13/cobra"
+)
+
+var licensesCmd = &cobra.Command{
+	Use:   "licenses",
+	Short: "Display the licenses of all the dependencies of this tool.",
+	RunE: func(cmd *cobra.Command, args []string) error {
+		return licenses.PrintLicenses()
+	},
+}

cmd/root.go

@@ -51,6 +51,7 @@ func Execute(ctx context.Context) error {
 	}
 
 	rootCmd.AddCommand(versionCmd)
+	rootCmd.AddCommand(licensesCmd)
 
 	rootCmd.AddCommand(pullCmd)
 	pullFlags.Init(pullCmd)

go.mod

@@ -6,9 +6,14 @@ require (
 	github.com/go-git/go-git/v5 v5.1.0
 	github.com/google/go-github/v32 v32.1.0
 	github.com/gorilla/mux v1.8.0
+	github.com/markbates/pkger v0.17.0
 	github.com/mitchellh/ioprogress v0.0.0-20180201004757-6a23b12fa88e
 	github.com/pkg/errors v0.8.1
 	github.com/spf13/cobra v1.0.0
+	github.com/spf13/pflag v1.0.5 // indirect
 	github.com/stretchr/testify v1.6.1
+	golang.org/x/crypto v0.0.0-20200820211705-5c72a883971a // indirect
+	golang.org/x/net v0.0.0-20200625001655-4c5254603344 // indirect
 	golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be
+	golang.org/x/sys v0.0.0-20200824131525-c12d262b63d8 // indirect
 )

internal/licenses/licenses.go

@@ -0,0 +1,41 @@
+package licenses
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+
+	"github.com/markbates/pkger"
+	"github.com/pkg/errors"
+)
+
+const errorMessage = "Error reading licenses."
+
+func PrintLicenses() error {
+	fmt.Println("This tool could not have been built without all the wonderful developer communities who maintain these dependencies.")
+	err := pkger.Walk("/.licenses", func(path string, info os.FileInfo, err error) error {
+		if err != nil {
+			return errors.Wrap(err, errorMessage)
+		}
+		if info.IsDir() {
+			return nil
+		}
+
+		reader, err := pkger.Open(path)
+		if err != nil {
+			return errors.Wrap(err, errorMessage)
+		}
+		defer reader.Close()
+		content, err := ioutil.ReadAll(reader)
+		if err != nil {
+			return errors.Wrap(err, errorMessage)
+		}
+		fmt.Println(string(content))
+
+		return nil
+	})
+	if err != nil {
+		return errors.Wrap(err, errorMessage)
+	}
+	return nil
+}