Replace viper with koanf (#4845)

* Migrate to koanf
* Use temp logger for crashes before config is initialised
* Remove snake case hacks
* Add migration for config file keys
* Add migration note for new migration
* Renamed viper functions
* Remove front-end viper workaround
* Correctly default scan options

pkg/sqlite/database.go

@@ -30,7 +30,7 @@ const (
 	dbConnTimeout = 30
 )
 
-var appSchemaVersion uint = 57
+var appSchemaVersion uint = 58
 
 //go:embed migrations/*.sql
 var migrationsBox embed.FS

pkg/sqlite/migrations/58_config_correct.up.sql

@@ -0,0 +1 @@
+-- no schema changes

pkg/sqlite/migrations/58_postmigrate.go

@@ -0,0 +1,143 @@
+package migrations
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"os"
+	"time"
+	"unicode"
+
+	"github.com/jmoiron/sqlx"
+	"github.com/spf13/cast"
+	"github.com/stashapp/stash/internal/manager/config"
+	"github.com/stashapp/stash/pkg/logger"
+	"github.com/stashapp/stash/pkg/sqlite"
+)
+
+type schema58Migrator struct {
+	migrator
+}
+
+func post58(ctx context.Context, db *sqlx.DB) error {
+	logger.Info("Running post-migration for schema version 58")
+
+	m := schema58Migrator{
+		migrator: migrator{
+			db: db,
+		},
+	}
+
+	return m.migrate()
+}
+
+func (m *schema58Migrator) migrate() error {
+	if err := m.migrateConfig(); err != nil {
+		return fmt.Errorf("failed to migrate config: %w", err)
+	}
+
+	return nil
+}
+
+// fromSnakeCase converts a string from snake_case to camelCase
+func (m *schema58Migrator) fromSnakeCase(v string) string {
+	var buf bytes.Buffer
+	leadingUnderscore := true
+	capvar := false
+	for i, c := range v {
+		switch {
+		case c == '_' && !leadingUnderscore && i > 0:
+			capvar = true
+		case c == '_' && leadingUnderscore:
+			buf.WriteRune(c)
+		case capvar:
+			buf.WriteRune(unicode.ToUpper(c))
+			capvar = false
+		default:
+			leadingUnderscore = false
+			buf.WriteRune(c)
+		}
+	}
+	return buf.String()
+}
+
+// fromSnakeCaseMap recursively converts a map using snake_case keys to camelCase keys
+func (m *schema58Migrator) fromSnakeCaseMap(mm map[string]interface{}) map[string]interface{} {
+	return m.fromSnakeCaseValue(mm).(map[string]interface{})
+}
+
+func (m *schema58Migrator) fromSnakeCaseValue(val interface{}) interface{} {
+	switch v := val.(type) {
+	case map[interface{}]interface{}:
+		ret := cast.ToStringMap(v)
+		for k, vv := range ret {
+			adjKey := m.fromSnakeCase(k)
+			ret[adjKey] = m.fromSnakeCaseValue(vv)
+		}
+		return ret
+	case map[string]interface{}:
+		ret := make(map[string]interface{})
+		for k, vv := range v {
+			adjKey := m.fromSnakeCase(k)
+			ret[adjKey] = m.fromSnakeCaseValue(vv)
+		}
+		return ret
+	case []interface{}:
+		ret := make([]interface{}, len(v))
+		for i, vv := range v {
+			ret[i] = m.fromSnakeCaseValue(vv)
+		}
+		return ret
+	default:
+		return v
+	}
+}
+
+func (m *schema58Migrator) migrateConfig() error {
+	c := config.GetInstance()
+
+	orgPath := c.GetConfigFile()
+
+	if orgPath == "" {
+		// no config file to migrate (usually in a test)
+		return nil
+	}
+
+	// save a backup of the original config file
+	backupPath := fmt.Sprintf("%s.57.%s", orgPath, time.Now().Format("20060102_150405"))
+
+	data, err := c.Marshal()
+	if err != nil {
+		return fmt.Errorf("failed to marshal backup config: %w", err)
+	}
+
+	logger.Infof("Backing up config to %s", backupPath)
+	if err := os.WriteFile(backupPath, data, 0644); err != nil {
+		return fmt.Errorf("failed to write backup config: %w", err)
+	}
+
+	// migrate the plugin and UI configs from snake_case to camelCase
+	ui := c.GetUIConfiguration()
+	if ui != nil {
+		ui = m.fromSnakeCaseMap(ui)
+		c.SetUIConfiguration(ui)
+	}
+
+	plugins := c.GetAllPluginConfiguration()
+	newPlugins := make(map[string]interface{})
+	for key, value := range plugins {
+		key = m.fromSnakeCase(key)
+		newPlugins[key] = m.fromSnakeCaseMap(value)
+	}
+
+	c.Set(config.PluginsSetting, newPlugins)
+	if err := c.Write(); err != nil {
+		return fmt.Errorf("failed to write config: %w", err)
+	}
+
+	return nil
+}
+
+func init() {
+	sqlite.RegisterPostMigration(58, post58)
+}