Change function name to FlattenMap and move it to its own package

Signed-off-by: joshuabezaleel <joshua.bezaleel@gmail.com>

pkg/build/buildkit/buildx.go

@@ -9,6 +9,7 @@ import (
 	"path/filepath"
 	"strings"
 
+	"get.porter.sh/porter/pkg/build/driverutil"
 	"get.porter.sh/porter/pkg/config"
 	"get.porter.sh/porter/pkg/experimental"
 	"get.porter.sh/porter/pkg/tracing"
@@ -90,7 +91,7 @@ func (b *Builder) BuildInvocationImage(ctx context.Context, manifest *manifest.M
 	buildArgs["BUNDLE_DIR"] = build.BUNDLE_DIR
 
 	convertedCustomInput := make(map[string]string)
-	convertedCustomInput, err = convertMap(manifest.Custom)
+	convertedCustomInput, err = driverutil.FlattenMap(manifest.Custom)
 	if err != nil {
 		return err
 	}

pkg/build/docker/docker.go

@@ -8,6 +8,7 @@ import (
 	"strings"
 
 	"get.porter.sh/porter/pkg/build"
+	"get.porter.sh/porter/pkg/build/driverutil"
 	portercontext "get.porter.sh/porter/pkg/context"
 	"get.porter.sh/porter/pkg/manifest"
 	"github.com/docker/cli/cli/command"
@@ -35,7 +36,7 @@ func (b *Builder) BuildInvocationImage(ctx context.Context, manifest *manifest.M
 	buildArgs["BUNDLE_DIR"] = &build.BUNDLE_DIR
 
 	convertedCustomInput := make(map[string]string)
-	convertedCustomInput, err := convertMap(manifest.Custom)
+	convertedCustomInput, err := driverutil.FlattenMap(manifest.Custom)
 	if err != nil {
 		return err
 	}
@@ -111,29 +112,3 @@ func (b *Builder) TagInvocationImage(ctx context.Context, origTag, newTag string
 	}
 	return nil
 }
-
-func convertMap(mapInput map[string]interface{}) (map[string]string, error) {
-	out := make(map[string]string)
-
-	for key, value := range mapInput {
-		switch v := value.(type) {
-		case string:
-			out[key] = v
-		case map[string]interface{}:
-			tmp, err := convertMap(v)
-			if err != nil {
-				return nil, err
-			}
-			for innerKey, innerValue := range tmp {
-				out[key+"."+innerKey] = innerValue
-			}
-		case map[string]string:
-			for innerKey, innerValue := range v {
-				out[key+"."+innerKey] = innerValue
-			}
-		default:
-			return nil, errors.Errorf("Unknown type %#v: %t", v, v)
-		}
-	}
-	return out, nil
-}

pkg/build/driverutil/driverutil.go

@@ -0,0 +1,33 @@
+package driverutil
+
+import (
+	"github.com/pkg/errors"
+)
+
+// FlattenMap recursively walks through nested map and flattent it
+// to one-level map of key-value with string type.
+func FlattenMap(mapInput map[string]interface{}) (map[string]string, error) {
+	out := make(map[string]string)
+
+	for key, value := range mapInput {
+		switch v := value.(type) {
+		case string:
+			out[key] = v
+		case map[string]interface{}:
+			tmp, err := FlattenMap(v)
+			if err != nil {
+				return nil, err
+			}
+			for innerKey, innerValue := range tmp {
+				out[key+"."+innerKey] = innerValue
+			}
+		case map[string]string:
+			for innerKey, innerValue := range v {
+				out[key+"."+innerKey] = innerValue
+			}
+		default:
+			return nil, errors.Errorf("Unknown type %#v: %t", v, v)
+		}
+	}
+	return out, nil
+}

pkg/build/buildkit/buildkit_test.go → pkg/build/driverutil/driverutil_test.go

@@ -1,4 +1,4 @@
-package buildkit
+package driverutil
 
 import (
 	"testing"
@@ -7,7 +7,7 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
-func TestConvertMap(t *testing.T) {
+func TestFlattenMap(t *testing.T) {
 	tt := []struct {
 		desc string
 		inp  map[string]interface{}
@@ -79,7 +79,7 @@ func TestConvertMap(t *testing.T) {
 
 	for _, tc := range tt {
 		t.Run(tc.desc, func(t *testing.T) {
-			out, err := convertMap(tc.inp)
+			out, err := FlattenMap(tc.inp)
 			if tc.err {
 				require.Error(t, err)
 				return