osbuild2: add support for org.osbuild.dnf.config stage

Add support for a new osbuild stage `org.osbuild.dnf.config`, for
configuring DNF.

Add unit tests for the new stage.

Related to https://github.com/osbuild/osbuild/pull/798.

Signed-off-by: Tomas Hozza <thozza@redhat.com>

internal/osbuild2/dnf_config_stage.go

@@ -0,0 +1,32 @@
+package osbuild2
+
+// DNFConfigStageOptions represents persistent DNF configuration.
+type DNFConfigStageOptions struct {
+	// List of DNF variables.
+	Variables []DNFVariable `json:"variables,omitempty"`
+}
+
+func (DNFConfigStageOptions) isStageOptions() {}
+
+// NewDNFConfigStageOptions creates a new DNFConfig Stage options object.
+func NewDNFConfigStageOptions(variables []DNFVariable) *DNFConfigStageOptions {
+	return &DNFConfigStageOptions{
+		Variables: variables,
+	}
+}
+
+// NewDNFConfigStage creates a new DNFConfig Stage object.
+func NewDNFConfigStage(options *DNFConfigStageOptions) *Stage {
+	return &Stage{
+		Type:    "org.osbuild.dnf.config",
+		Options: options,
+	}
+}
+
+// DNFVariable represents a single DNF variable.
+type DNFVariable struct {
+	// Name of the variable.
+	Name string `json:"name"`
+	// Value of the variable.
+	Value string `json:"value"`
+}

internal/osbuild2/dnf_config_stage_test.go

@@ -0,0 +1,31 @@
+package osbuild2
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestNewDNFConfigStageOptions(t *testing.T) {
+	variables := []DNFVariable{
+		{
+			Name:  "release",
+			Value: "8.4",
+		},
+	}
+
+	expectedOptions := &DNFConfigStageOptions{
+		Variables: variables,
+	}
+	actualOptions := NewDNFConfigStageOptions(variables)
+	assert.Equal(t, expectedOptions, actualOptions)
+}
+
+func TestNewDNFConfigStage(t *testing.T) {
+	expectedStage := &Stage{
+		Type:    "org.osbuild.dnf.config",
+		Options: &DNFConfigStageOptions{},
+	}
+	actualStage := NewDNFConfigStage(&DNFConfigStageOptions{})
+	assert.Equal(t, expectedStage, actualStage)
+}

internal/osbuild2/stage.go

@@ -69,6 +69,8 @@ func (stage *Stage) UnmarshalJSON(data []byte) error {
 		options = new(CloudInitStageOptions)
 	case "org.osbuild.chrony":
 		options = new(ChronyStageOptions)
+	case "org.osbuild.dnf.config":
+		options = new(DNFConfigStageOptions)
 	case "org.osbuild.dracut":
 		options = new(DracutStageOptions)
 	case "org.osbuild.dracut.conf":

internal/osbuild2/stage_test.go

@@ -136,6 +136,16 @@ func TestStage_UnmarshalJSON(t *testing.T) {
 				data: []byte(`{"type":"org.osbuild.chrony","options":{"servers":[{"hostname":"127.0.0.1","minpoll":0,"maxpoll":4,"iburst":true,"prefer":false},{"hostname":"ntp.example.com"}],"leapsectz":""}}`),
 			},
 		},
+		{
+			name: "dnf-config",
+			fields: fields{
+				Type:    "org.osbuild.dnf.config",
+				Options: &DNFConfigStageOptions{},
+			},
+			args: args{
+				data: []byte(`{"type":"org.osbuild.dnf.config","options":{}}`),
+			},
+		},
 		{
 			name: "dracut",
 			fields: fields{