Allow json output

Signed-off-by: Bryan Frimin <bryan@probo.com>

pkg/bootstrap/write.go

@@ -15,6 +15,7 @@
 package bootstrap
 
 import (
+	"encoding/json"
 	"fmt"
 	"os"
 	"path/filepath"
@@ -23,7 +24,14 @@ import (
 	"sigs.k8s.io/yaml"
 )
 
-func WriteConfig(cfg *probodconfig.FullConfig, path string) error {
+type Format string
+
+const (
+	FormatYAML Format = "yaml"
+	FormatJSON Format = "json"
+)
+
+func WriteConfig(cfg *probodconfig.FullConfig, path string, format Format) error {
 	dir := filepath.Dir(path)
 	if err := os.MkdirAll(dir, 0755); err != nil {
 		return fmt.Errorf("create directory %s: %w", dir, err)
@@ -41,9 +49,19 @@ func WriteConfig(cfg *probodconfig.FullConfig, path string) error {
 
 	pruned := pruneEmptyStrings(tree)
 
-	data, err = yaml.Marshal(pruned)
-	if err != nil {
-		return fmt.Errorf("marshal pruned config: %w", err)
+	switch format {
+	case FormatJSON:
+		data, err = json.MarshalIndent(pruned, "", "  ")
+		if err != nil {
+			return fmt.Errorf("marshal pruned config as json: %w", err)
+		}
+	case FormatYAML:
+		data, err = yaml.Marshal(pruned)
+		if err != nil {
+			return fmt.Errorf("marshal pruned config as yaml: %w", err)
+		}
+	default:
+		return fmt.Errorf("unsupported config format: %q", format)
 	}
 
 	if err := os.WriteFile(path, data, 0600); err != nil {

pkg/bootstrap/write_test.go

@@ -15,6 +15,7 @@
 package bootstrap
 
 import (
+	"encoding/json"
 	"os"
 	"path/filepath"
 	"testing"
@@ -39,7 +40,7 @@ func TestWriteConfig(t *testing.T) {
 		},
 	}
 
-	err := WriteConfig(cfg, configPath)
+	err := WriteConfig(cfg, configPath, FormatYAML)
 	require.NoError(t, err)
 
 	data, err := os.ReadFile(configPath)
@@ -63,7 +64,7 @@ func TestWriteConfig_CreatesDirectory(t *testing.T) {
 		Probod: probodconfig.Config{BaseURL: "http://localhost:8080"},
 	}
 
-	err := WriteConfig(cfg, configPath)
+	err := WriteConfig(cfg, configPath, FormatYAML)
 	require.NoError(t, err)
 
 	_, err = os.Stat(configPath)
@@ -76,7 +77,7 @@ func TestWriteConfig_FilePermissions(t *testing.T) {
 
 	cfg := &probodconfig.FullConfig{}
 
-	err := WriteConfig(cfg, configPath)
+	err := WriteConfig(cfg, configPath, FormatYAML)
 	require.NoError(t, err)
 
 	info, err := os.Stat(configPath)
@@ -108,7 +109,7 @@ func TestWriteConfig_DropsEmptyStrings(t *testing.T) {
 		},
 	}
 
-	err := WriteConfig(cfg, configPath)
+	err := WriteConfig(cfg, configPath, FormatYAML)
 	require.NoError(t, err)
 
 	data, err := os.ReadFile(configPath)
@@ -205,7 +206,7 @@ func TestWriteConfig_CompleteConfig(t *testing.T) {
 		},
 	}
 
-	err := WriteConfig(cfg, configPath)
+	err := WriteConfig(cfg, configPath, FormatYAML)
 	require.NoError(t, err)
 
 	data, err := os.ReadFile(configPath)
@@ -226,3 +227,52 @@ func TestWriteConfig_CompleteConfig(t *testing.T) {
 	require.Len(t, loaded.Probod.Connectors, 1)
 	assert.Equal(t, "SLACK", loaded.Probod.Connectors[0].Provider)
 }
+
+func TestWriteConfig_JSON(t *testing.T) {
+	tmpDir := t.TempDir()
+	configPath := filepath.Join(tmpDir, "probod.json")
+
+	cfg := &probodconfig.FullConfig{
+		Unit: probodconfig.UnitConfig{
+			Metrics: probodconfig.MetricsConfig{Addr: "localhost:9090"},
+		},
+		Probod: probodconfig.Config{
+			BaseURL:       "http://localhost:8080",
+			EncryptionKey: "",
+		},
+	}
+
+	err := WriteConfig(cfg, configPath, FormatJSON)
+	require.NoError(t, err)
+
+	data, err := os.ReadFile(configPath)
+	require.NoError(t, err)
+
+	var tree map[string]any
+
+	err = json.Unmarshal(data, &tree)
+	require.NoError(t, err)
+
+	probod, ok := tree["probod"].(map[string]any)
+	require.True(t, ok)
+	assert.Equal(t, "http://localhost:8080", probod["base-url"])
+	assert.NotContains(t, probod, "encryption-key")
+
+	var loaded probodconfig.FullConfig
+
+	err = json.Unmarshal(data, &loaded)
+	require.NoError(t, err)
+
+	assert.Equal(t, cfg.Unit.Metrics.Addr, loaded.Unit.Metrics.Addr)
+	assert.Equal(t, cfg.Probod.BaseURL, loaded.Probod.BaseURL)
+}
+
+func TestWriteConfig_UnsupportedFormat(t *testing.T) {
+	tmpDir := t.TempDir()
+	configPath := filepath.Join(tmpDir, "probod.txt")
+
+	cfg := &probodconfig.FullConfig{}
+
+	err := WriteConfig(cfg, configPath, Format("toml"))
+	require.Error(t, err)
+}