add dot-accessor notation

Environment variables are unaffected by Delete, making it misleading —
callers would expect a key to be fully gone but env vars would still
resolve. Sub is the better abstraction for scoped config.

.github/workflows/codeql-analysis.yml

@@ -36,31 +36,20 @@ jobs:
 
     steps:
     - name: Checkout repository
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
 
     - name: Install Go
-      uses: actions/setup-go@v4
+      uses: actions/setup-go@v5
       with:
         go-version-file: go.mod
 
     - name: Initialize CodeQL
-      uses: github/codeql-action/init@v2
+      uses: github/codeql-action/init@v3
       with:
         languages: ${{ matrix.language }}
 
     - name: Autobuild
-      uses: github/codeql-action/autobuild@v2
+      uses: github/codeql-action/autobuild@v3
-
-    # ℹ️ Command-line programs to run using the OS shell.
-    # 📚 https://git.io/JvXDl
-
-    # ✏️ If the Autobuild fails above, remove it and uncomment the following three lines
-    #    and modify them (or add more) to build your code if your project
-    #    uses a compiled language
-
-    #- run: |
-    #   make bootstrap
-    #   make release
 
     - name: Perform CodeQL Analysis
-      uses: github/codeql-action/analyze@v2
+      uses: github/codeql-action/analyze@v3

.github/workflows/govulncheck.yml

@@ -12,7 +12,7 @@ jobs:
     runs-on: ubuntu-latest
     name: Run govulncheck
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - id: govulncheck
         uses: golang/govulncheck-action@v1
         with:

README.md

@@ -68,16 +68,25 @@ timeout = "30s"
 client_id = "abc123"
 ```
 
-Access nested values using `GetStringMap` and type assertions:
+Use `Sub()` to get a scoped ConfigManager for a nested section:
+
+```go
+cloud := jety.Sub("services")
+if cloud != nil {
+    inner := cloud.Sub("cloud")
+    if inner != nil {
+        varValue := inner.GetString("var")      // "xyz"
+        timeout := inner.GetDuration("timeout")  // 30s
+    }
+}
+```
+
+Or access nested values directly with `GetStringMap` and type assertions:
 
 ```go
 services := jety.GetStringMap("services")
 cloud := services["cloud"].(map[string]any)
 varValue := cloud["var"].(string)  // "xyz"
-
-// For deeper nesting
-auth := cloud["auth"].(map[string]any)
-clientID := auth["client_id"].(string)  // "abc123"
 ```
 
 ### Environment Variable Overrides
@@ -124,6 +133,8 @@ export MYAPP_SERVICES_CLOUD_VAR=override_value
 | ------------------------ | ------------------------ |
 | `Set(key, value)`        | Set a value              |
 | `SetDefault(key, value)` | Set a default value      |
+| `Delete(key)`            | Remove a key             |
+| `Sub(key)`               | Get scoped sub-config    |
 | `Get(key)`               | Get raw value            |
 | `GetString(key)`         | Get as string            |
 | `GetInt(key)`            | Get as int               |

default.go

@@ -88,6 +88,10 @@ func SetString(key string, value string) {
 	defaultConfigManager.SetString(key, value)
 }
 
+func Sub(key string) *ConfigManager {
+	return defaultConfigManager.Sub(key)
+}
+
 func SetConfigDir(path string) {
 	defaultConfigManager.SetConfigDir(path)
 }

getters.go

@@ -8,17 +8,71 @@ import (
 )
 
 // resolve looks up a key in combinedConfig, falling back to envConfig.
+// It supports dot notation (e.g., "services.mas.server") to traverse nested maps.
 func (c *ConfigManager) resolve(key string) (ConfigMap, bool) {
 	lower := strings.ToLower(key)
+
+	// First, try direct lookup (for top-level keys or keys without dots)
 	if v, ok := c.combinedConfig[lower]; ok {
 		return v, true
 	}
 	if v, ok := c.envConfig[lower]; ok {
 		return v, true
 	}
+
+	// If key contains dots, try traversing nested maps
+	if strings.Contains(lower, ".") {
+		if v, ok := c.resolveNested(lower, c.combinedConfig); ok {
+			return v, true
+		}
+		if v, ok := c.resolveNested(lower, c.envConfig); ok {
+			return v, true
+		}
+	}
+
 	return ConfigMap{}, false
 }
 
+// resolveNested traverses nested maps using dot-separated key paths.
+func (c *ConfigManager) resolveNested(key string, config map[string]ConfigMap) (ConfigMap, bool) {
+	parts := strings.Split(key, ".")
+	if len(parts) < 2 {
+		return ConfigMap{}, false
+	}
+
+	// Look up the first part in the config
+	firstPart := parts[0]
+	entry, ok := config[firstPart]
+	if !ok {
+		return ConfigMap{}, false
+	}
+
+	// Traverse the remaining parts through nested maps
+	current := entry.Value
+	for i := 1; i < len(parts); i++ {
+		m, ok := current.(map[string]any)
+		if !ok {
+			return ConfigMap{}, false
+		}
+
+		// Try case-insensitive lookup in the nested map
+		part := parts[i]
+		found := false
+		for k, v := range m {
+			if strings.EqualFold(k, part) {
+				current = v
+				found = true
+				break
+			}
+		}
+		if !found {
+			return ConfigMap{}, false
+		}
+	}
+
+	return ConfigMap{Key: key, Value: current}, true
+}
+
 func (c *ConfigManager) Get(key string) any {
 	c.mutex.RLock()
 	defer c.mutex.RUnlock()

jety.go

@@ -308,6 +308,31 @@ func readFile(filename string, fileType configType) (map[string]any, error) {
 	}
 }
 
+// Sub returns a new ConfigManager rooted at the given key. The key must
+// refer to a map value (e.g., from a nested TOML/YAML/JSON section).
+// The returned ConfigManager has the nested map loaded as its default
+// config, and does not inherit the parent's environment prefix, overrides,
+// or config file. Returns nil if the key does not exist or is not a map.
+func (c *ConfigManager) Sub(key string) *ConfigManager {
+	c.mutex.RLock()
+	defer c.mutex.RUnlock()
+	v, ok := c.resolve(key)
+	if !ok {
+		return nil
+	}
+	m, ok := v.Value.(map[string]any)
+	if !ok {
+		return nil
+	}
+	sub := NewConfigManager()
+	for k, val := range m {
+		lower := strings.ToLower(k)
+		sub.defaultConfig[lower] = ConfigMap{Key: k, Value: val}
+		sub.combinedConfig[lower] = ConfigMap{Key: k, Value: val}
+	}
+	return sub
+}
+
 func (c *ConfigManager) SetConfigDir(path string) {
 	c.mutex.Lock()
 	defer c.mutex.Unlock()

jety_test.go

@@ -1554,3 +1554,245 @@ func TestPackageLevelGetInt64(t *testing.T) {
 		t.Errorf("GetInt64(bignum) = %d, want 9223372036854775807", got)
 	}
 }
+
+func TestSub(t *testing.T) {
+	dir := t.TempDir()
+	configFile := filepath.Join(dir, "config.toml")
+	if err := os.WriteFile(configFile, []byte(tomlConfig), 0o644); err != nil {
+		t.Fatal(err)
+	}
+
+	cm := NewConfigManager()
+	cm.SetConfigFile(configFile)
+	if err := cm.SetConfigType("toml"); err != nil {
+		t.Fatal(err)
+	}
+	if err := cm.ReadInConfig(); err != nil {
+		t.Fatal(err)
+	}
+
+	sub := cm.Sub("database")
+	if sub == nil {
+		t.Fatal("Sub(database) returned nil")
+	}
+
+	host := sub.GetString("host")
+	if host != "db.example.com" {
+		t.Errorf("Sub(database).GetString(host) = %q, want %q", host, "db.example.com")
+	}
+
+	port := sub.GetInt("port")
+	if port != 5432 {
+		t.Errorf("Sub(database).GetInt(port) = %d, want 5432", port)
+	}
+}
+
+func TestSubNonExistentKey(t *testing.T) {
+	cm := NewConfigManager()
+	cm.SetDefault("simple", "value")
+
+	sub := cm.Sub("nonexistent")
+	if sub != nil {
+		t.Error("Sub(nonexistent) should return nil")
+	}
+}
+
+func TestSubNonMapKey(t *testing.T) {
+	cm := NewConfigManager()
+	cm.Set("name", "plain-string")
+
+	sub := cm.Sub("name")
+	if sub != nil {
+		t.Error("Sub on a non-map key should return nil")
+	}
+}
+
+func TestSubIsIndependent(t *testing.T) {
+	cm := NewConfigManager()
+	cm.Set("section", map[string]any{
+		"key1": "val1",
+		"key2": "val2",
+	})
+
+	sub := cm.Sub("section")
+	if sub == nil {
+		t.Fatal("Sub(section) returned nil")
+	}
+
+	// Modifying sub should not affect parent
+	sub.Set("key1", "modified")
+	if sub.GetString("key1") != "modified" {
+		t.Error("sub should reflect the Set")
+	}
+
+	parentSection := cm.Get("section").(map[string]any)
+	if parentSection["key1"] != "val1" {
+		t.Error("modifying sub should not affect parent")
+	}
+}
+
+func TestPackageLevelSub(t *testing.T) {
+	defaultConfigManager = NewConfigManager()
+	Set("db", map[string]any{"host": "localhost", "port": 5432})
+
+	sub := Sub("db")
+	if sub == nil {
+		t.Fatal("package-level Sub returned nil")
+	}
+	if sub.GetString("host") != "localhost" {
+		t.Errorf("Sub(db).GetString(host) = %q, want %q", sub.GetString("host"), "localhost")
+	}
+	if sub.GetInt("port") != 5432 {
+		t.Errorf("Sub(db).GetInt(port) = %d, want 5432", sub.GetInt("port"))
+	}
+}
+
+func TestDotNotationAccess(t *testing.T) {
+	const tomlWithNested = `
+port = 8080
+
+[services.mas]
+server = "192.168.1.15"
+user = "central"
+disabled = false
+
+[services.salesforce.prod]
+host = "sf.example.com"
+port = 443
+`
+
+	dir := t.TempDir()
+	configFile := filepath.Join(dir, "nested.toml")
+	if err := os.WriteFile(configFile, []byte(tomlWithNested), 0o644); err != nil {
+		t.Fatal(err)
+	}
+
+	cm := NewConfigManager()
+	cm.SetConfigFile(configFile)
+	if err := cm.SetConfigType("toml"); err != nil {
+		t.Fatal(err)
+	}
+	if err := cm.ReadInConfig(); err != nil {
+		t.Fatal(err)
+	}
+
+	// Top-level key should still work
+	if got := cm.GetInt("port"); got != 8080 {
+		t.Errorf("GetInt(port) = %d, want 8080", got)
+	}
+
+	// Dot notation for nested string
+	if got := cm.GetString("services.mas.server"); got != "192.168.1.15" {
+		t.Errorf("GetString(services.mas.server) = %q, want %q", got, "192.168.1.15")
+	}
+	if got := cm.GetString("services.mas.user"); got != "central" {
+		t.Errorf("GetString(services.mas.user) = %q, want %q", got, "central")
+	}
+
+	// Dot notation for nested bool
+	if got := cm.GetBool("services.mas.disabled"); got != false {
+		t.Errorf("GetBool(services.mas.disabled) = %v, want false", got)
+	}
+
+	// Dot notation for nested map
+	masMap := cm.GetStringMap("services.mas")
+	if masMap == nil {
+		t.Fatal("GetStringMap(services.mas) = nil")
+	}
+	if masMap["server"] != "192.168.1.15" {
+		t.Errorf("services.mas map server = %v, want %q", masMap["server"], "192.168.1.15")
+	}
+
+	// Three levels deep
+	if got := cm.GetString("services.salesforce.prod.host"); got != "sf.example.com" {
+		t.Errorf("GetString(services.salesforce.prod.host) = %q, want %q", got, "sf.example.com")
+	}
+	if got := cm.GetInt("services.salesforce.prod.port"); got != 443 {
+		t.Errorf("GetInt(services.salesforce.prod.port) = %d, want 443", got)
+	}
+
+	// GetStringMap at intermediate level
+	sfProdMap := cm.GetStringMap("services.salesforce.prod")
+	if sfProdMap == nil {
+		t.Fatal("GetStringMap(services.salesforce.prod) = nil")
+	}
+	if sfProdMap["host"] != "sf.example.com" {
+		t.Errorf("salesforce.prod map host = %v, want %q", sfProdMap["host"], "sf.example.com")
+	}
+
+	// Nonexistent nested key should return zero value
+	if got := cm.GetString("services.mas.nonexistent"); got != "" {
+		t.Errorf("GetString(services.mas.nonexistent) = %q, want empty", got)
+	}
+	if got := cm.GetStringMap("services.nonexistent"); got != nil {
+		t.Errorf("GetStringMap(services.nonexistent) = %v, want nil", got)
+	}
+}
+
+func TestDotNotationCaseInsensitive(t *testing.T) {
+	cm := NewConfigManager()
+	cm.Set("services", map[string]any{
+		"MAS": map[string]any{
+			"Server": "192.168.1.15",
+		},
+	})
+
+	// Should work regardless of case
+	if got := cm.GetString("services.mas.server"); got != "192.168.1.15" {
+		t.Errorf("GetString(services.mas.server) = %q, want %q", got, "192.168.1.15")
+	}
+	if got := cm.GetString("SERVICES.MAS.SERVER"); got != "192.168.1.15" {
+		t.Errorf("GetString(SERVICES.MAS.SERVER) = %q, want %q", got, "192.168.1.15")
+	}
+	if got := cm.GetString("Services.Mas.Server"); got != "192.168.1.15" {
+		t.Errorf("GetString(Services.Mas.Server) = %q, want %q", got, "192.168.1.15")
+	}
+}
+
+func TestDotNotationWithAllGetters(t *testing.T) {
+	cm := NewConfigManager()
+	cm.Set("config", map[string]any{
+		"nested": map[string]any{
+			"string":  "hello",
+			"int":     42,
+			"int64":   int64(9223372036854775807),
+			"float":   3.14,
+			"bool":    true,
+			"dur":     "30s",
+			"strings": []string{"a", "b", "c"},
+			"ints":    []any{1, 2, 3},
+			"map":     map[string]any{"key": "value"},
+		},
+	})
+
+	if got := cm.Get("config.nested.string"); got != "hello" {
+		t.Errorf("Get(config.nested.string) = %v, want %q", got, "hello")
+	}
+	if got := cm.GetString("config.nested.string"); got != "hello" {
+		t.Errorf("GetString(config.nested.string) = %q, want %q", got, "hello")
+	}
+	if got := cm.GetInt("config.nested.int"); got != 42 {
+		t.Errorf("GetInt(config.nested.int) = %d, want 42", got)
+	}
+	if got := cm.GetInt64("config.nested.int64"); got != 9223372036854775807 {
+		t.Errorf("GetInt64(config.nested.int64) = %d, want 9223372036854775807", got)
+	}
+	if got := cm.GetFloat64("config.nested.float"); got != 3.14 {
+		t.Errorf("GetFloat64(config.nested.float) = %f, want 3.14", got)
+	}
+	if got := cm.GetBool("config.nested.bool"); got != true {
+		t.Errorf("GetBool(config.nested.bool) = %v, want true", got)
+	}
+	if got := cm.GetDuration("config.nested.dur"); got != 30*time.Second {
+		t.Errorf("GetDuration(config.nested.dur) = %v, want 30s", got)
+	}
+	if got := cm.GetStringSlice("config.nested.strings"); len(got) != 3 || got[0] != "a" {
+		t.Errorf("GetStringSlice(config.nested.strings) = %v, want [a b c]", got)
+	}
+	if got := cm.GetIntSlice("config.nested.ints"); len(got) != 3 || got[0] != 1 {
+		t.Errorf("GetIntSlice(config.nested.ints) = %v, want [1 2 3]", got)
+	}
+	if got := cm.GetStringMap("config.nested.map"); got == nil || got["key"] != "value" {
+		t.Errorf("GetStringMap(config.nested.map) = %v, want map[key:value]", got)
+	}
+}