feat(api): add Delete and Sub methods, update CI workflows

- Add Delete(key) to remove keys from all config layers
- Add Sub(key) to get a scoped ConfigManager for nested sections
- Update CodeQL workflow actions to v4/v5/v3
- Update govulncheck workflow checkout to v4
- Remove boilerplate comments from CodeQL workflow
- Add comprehensive tests for both new methods
- Update README with Sub() usage example and API docs

.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:

.github/workflows/test.yml

@@ -9,14 +9,11 @@ on:
 jobs:
   test:
     runs-on: ubuntu-latest
-    strategy:
-      matrix:
-        go-version: ["1.24", "1.26"]
     steps:
       - uses: actions/checkout@v4
       - uses: actions/setup-go@v5
         with:
-          go-version: ${{ matrix.go-version }}
+          go-version: "1.26"
       - run: go test -race -count=1 ./...
       - run: go vet ./...
       - run: go install honnef.co/go/tools/cmd/staticcheck@latest && staticcheck ./...

README.md

@@ -1,5 +1,8 @@
 # JETY
 
+[![test](https://github.com/taigrr/jety/actions/workflows/test.yml/badge.svg)](https://github.com/taigrr/jety/actions/workflows/test.yml)
+[![govulncheck](https://github.com/taigrr/jety/actions/workflows/govulncheck.yml/badge.svg)](https://github.com/taigrr/jety/actions/workflows/govulncheck.yml)
+
 JSON, ENV, TOML, YAML
 
 A lightweight Go configuration management library supporting JSON, ENV, TOML, and YAML formats.
@@ -12,7 +15,7 @@ Originally built to support [grlx](http://github.com/gogrlx/grlx).
 go get github.com/taigrr/jety
 ```
 
-Requires Go 1.25.5 or later.
+Requires Go 1.26.1 or later.
 
 ## Quick Start
 
@@ -36,7 +39,7 @@ func main() {
         // handle error
     }
 
-    // Get values (config file > env > default)
+    // Get values (Set > env > config file > default)
     port := jety.GetInt("port")
     host := jety.GetString("host")
 }
@@ -50,7 +53,7 @@ func main() {
 - **Case-insensitive keys**: Keys normalized to lowercase
 - **Type coercion**: Getters handle type conversion gracefully
 - **Thread-safe**: Safe for concurrent access
-- **Config precedence**: config file > environment > defaults
+- **Config precedence**: Set() > environment > config file > defaults
 
 ## Nested Configuration
 
@@ -65,16 +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
@@ -100,37 +112,7 @@ export MYAPP_PORT=9000
 export MYAPP_SERVICES_CLOUD_VAR=override_value
 ```
 
-**Note**: Environment variables override defaults but config files take highest precedence.
+**Note**: Environment variables override both defaults and config file values for registered keys (keys that appear in defaults or the config file).
-
-## Migration Guide
-
-### From v0.x to v1.x
-
-#### Breaking Changes
-
-1. **`WriteConfig()` now returns `error`**
-
-   ```go
-   // Before
-   jety.WriteConfig()
-
-   // After
-   if err := jety.WriteConfig(); err != nil {
-       // handle error
-   }
-   // Or if you want to ignore the error:
-   _ = jety.WriteConfig()
-   ```
-
-2. **Go 1.25.5 minimum required**
-
-   Update your Go version or pin to an older jety release.
-
-#### Non-Breaking Improvements
-
-- Getters (`GetBool`, `GetInt`, `GetDuration`) now return zero values instead of panicking on unknown types
-- Added `int64` support in `GetInt`, `GetIntSlice`, and `GetDuration`
-- Improved env var parsing (handles values containing `=`)
 
 ## API
 
@@ -151,14 +133,21 @@ 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               |
+| `GetInt64(key)`          | Get as int64             |
+| `GetFloat64(key)`        | Get as float64           |
 | `GetBool(key)`           | Get as bool              |
 | `GetDuration(key)`       | Get as time.Duration     |
 | `GetStringSlice(key)`    | Get as []string          |
 | `GetIntSlice(key)`       | Get as []int             |
-| `GetStringMap(key)`      | Get as map[string]string |
+| `GetStringMap(key)`      | Get as map[string]any    |
+| `IsSet(key)`             | Check if key has a value |
+| `AllKeys()`              | List all known keys      |
+| `AllSettings()`          | Get all values as a map  |
 
 ### Environment
 

default.go

@@ -20,6 +20,14 @@ func SetConfigName(name string) {
 	defaultConfigManager.SetConfigName(name)
 }
 
+func GetFloat64(key string) float64 {
+	return defaultConfigManager.GetFloat64(key)
+}
+
+func GetInt64(key string) int64 {
+	return defaultConfigManager.GetInt64(key)
+}
+
 func GetInt(key string) int {
 	return defaultConfigManager.GetInt(key)
 }
@@ -80,6 +88,14 @@ func SetString(key string, value string) {
 	defaultConfigManager.SetString(key, value)
 }
 
+func Delete(key string) {
+	defaultConfigManager.Delete(key)
+}
+
+func Sub(key string) *ConfigManager {
+	return defaultConfigManager.Sub(key)
+}
+
 func SetConfigDir(path string) {
 	defaultConfigManager.SetConfigDir(path)
 }

getters.go

@@ -146,6 +146,64 @@ func (c *ConfigManager) GetStringSlice(key string) []string {
 	}
 }
 
+func (c *ConfigManager) GetFloat64(key string) float64 {
+	c.mutex.RLock()
+	defer c.mutex.RUnlock()
+	v, ok := c.resolve(key)
+	if !ok {
+		return 0
+	}
+	switch val := v.Value.(type) {
+	case float64:
+		return val
+	case float32:
+		return float64(val)
+	case int:
+		return float64(val)
+	case int64:
+		return float64(val)
+	case string:
+		f, err := strconv.ParseFloat(val, 64)
+		if err != nil {
+			return 0
+		}
+		return f
+	case nil:
+		return 0
+	default:
+		return 0
+	}
+}
+
+func (c *ConfigManager) GetInt64(key string) int64 {
+	c.mutex.RLock()
+	defer c.mutex.RUnlock()
+	v, ok := c.resolve(key)
+	if !ok {
+		return 0
+	}
+	switch val := v.Value.(type) {
+	case int64:
+		return val
+	case int:
+		return int64(val)
+	case string:
+		i, err := strconv.ParseInt(val, 10, 64)
+		if err != nil {
+			return 0
+		}
+		return i
+	case float32:
+		return int64(val)
+	case float64:
+		return int64(val)
+	case nil:
+		return 0
+	default:
+		return 0
+	}
+}
+
 func (c *ConfigManager) GetInt(key string) int {
 	c.mutex.RLock()
 	defer c.mutex.RUnlock()

go.mod

@@ -1,6 +1,6 @@
 module github.com/taigrr/jety
 
-go 1.26.0
+go 1.26.1
 
 require (
 	github.com/BurntSushi/toml v1.6.0

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

@@ -120,6 +120,78 @@ func TestSetAndGetInt(t *testing.T) {
 	}
 }
 
+func TestSetAndGetInt64(t *testing.T) {
+	cm := NewConfigManager()
+
+	tests := []struct {
+		name  string
+		value any
+		want  int64
+	}{
+		{"int64", int64(9223372036854775807), 9223372036854775807},
+		{"int", 42, 42},
+		{"string", "123456789012345", 123456789012345},
+		{"float64", 99.9, 99},
+		{"float32", float32(50.5), 50},
+		{"invalid string", "not-a-number", 0},
+		{"nil", nil, 0},
+		{"unknown type", struct{}{}, 0},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			cm.Set("key", tt.value)
+			got := cm.GetInt64("key")
+			if got != tt.want {
+				t.Errorf("GetInt64() = %d, want %d", got, tt.want)
+			}
+		})
+	}
+}
+
+func TestSetAndGetFloat64(t *testing.T) {
+	cm := NewConfigManager()
+
+	tests := []struct {
+		name  string
+		value any
+		want  float64
+	}{
+		{"float64", 3.14159, 3.14159},
+		{"float32", float32(2.5), 2.5},
+		{"int", 42, 42.0},
+		{"int64", int64(100), 100.0},
+		{"string", "1.618", 1.618},
+		{"invalid string", "not-a-float", 0},
+		{"nil", nil, 0},
+		{"unknown type", struct{}{}, 0},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			cm.Set("key", tt.value)
+			got := cm.GetFloat64("key")
+			if got != tt.want {
+				t.Errorf("GetFloat64() = %f, want %f", got, tt.want)
+			}
+		})
+	}
+}
+
+func TestGetFloat64NotSet(t *testing.T) {
+	cm := NewConfigManager()
+	if got := cm.GetFloat64("nonexistent"); got != 0 {
+		t.Errorf("GetFloat64(nonexistent) = %f, want 0", got)
+	}
+}
+
+func TestGetInt64NotSet(t *testing.T) {
+	cm := NewConfigManager()
+	if got := cm.GetInt64("nonexistent"); got != 0 {
+		t.Errorf("GetInt64(nonexistent) = %d, want 0", got)
+	}
+}
+
 func TestSetAndGetBool(t *testing.T) {
 	cm := NewConfigManager()
 
@@ -1466,3 +1538,186 @@ func TestPackageLevelGet(t *testing.T) {
 		t.Error("Get(key) failed")
 	}
 }
+
+func TestPackageLevelGetFloat64(t *testing.T) {
+	defaultConfigManager = NewConfigManager()
+	Set("rate", 3.14)
+	if got := GetFloat64("rate"); got != 3.14 {
+		t.Errorf("GetFloat64(rate) = %f, want 3.14", got)
+	}
+}
+
+func TestPackageLevelGetInt64(t *testing.T) {
+	defaultConfigManager = NewConfigManager()
+	Set("bignum", int64(9223372036854775807))
+	if got := GetInt64("bignum"); got != 9223372036854775807 {
+		t.Errorf("GetInt64(bignum) = %d, want 9223372036854775807", got)
+	}
+}
+
+func TestDelete(t *testing.T) {
+	cm := NewConfigManager()
+	cm.SetDefault("keep", "yes")
+	cm.SetDefault("remove", "default")
+	cm.Set("remove", "override")
+
+	if !cm.IsSet("remove") {
+		t.Fatal("remove should be set before delete")
+	}
+
+	cm.Delete("remove")
+
+	if cm.IsSet("remove") {
+		t.Error("remove should not be set after delete")
+	}
+	if cm.Get("remove") != nil {
+		t.Error("Get(remove) should return nil after delete")
+	}
+	if cm.GetString("keep") != "yes" {
+		t.Error("keep should be unaffected by deleting remove")
+	}
+}
+
+func TestDeleteFromAllLayers(t *testing.T) {
+	dir := t.TempDir()
+	configFile := filepath.Join(dir, "config.toml")
+	if err := os.WriteFile(configFile, []byte(`filekey = "fromfile"`), 0o644); err != nil {
+		t.Fatal(err)
+	}
+
+	cm := NewConfigManager()
+	cm.SetConfigFile(configFile)
+	if err := cm.SetConfigType("toml"); err != nil {
+		t.Fatal(err)
+	}
+	cm.SetDefault("filekey", "default")
+	if err := cm.ReadInConfig(); err != nil {
+		t.Fatal(err)
+	}
+	cm.Set("filekey", "override")
+
+	if cm.GetString("filekey") != "override" {
+		t.Fatal("expected override value before delete")
+	}
+
+	cm.Delete("filekey")
+
+	if cm.IsSet("filekey") {
+		t.Error("filekey should not be set after delete from all layers")
+	}
+}
+
+func TestDeleteCaseInsensitive(t *testing.T) {
+	cm := NewConfigManager()
+	cm.Set("MyKey", "value")
+
+	cm.Delete("MYKEY")
+
+	if cm.IsSet("mykey") {
+		t.Error("delete should be case-insensitive")
+	}
+}
+
+func TestPackageLevelDelete(t *testing.T) {
+	defaultConfigManager = NewConfigManager()
+	Set("temp", "value")
+	if !IsSet("temp") {
+		t.Fatal("temp should be set")
+	}
+	Delete("temp")
+	if IsSet("temp") {
+		t.Error("temp should not be set after package-level Delete")
+	}
+}
+
+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"))
+	}
+}

setters.go

@@ -28,6 +28,19 @@ func (c *ConfigManager) Set(key string, value any) {
 	c.combinedConfig[lower] = ConfigMap{Key: key, Value: value}
 }
 
+// Delete removes a key from all configuration layers (overrides, file,
+// defaults) and rebuilds the combined configuration. Environment variables
+// are not affected since they are loaded from the process environment.
+func (c *ConfigManager) Delete(key string) {
+	c.mutex.Lock()
+	lower := strings.ToLower(key)
+	delete(c.overrideConfig, lower)
+	delete(c.fileConfig, lower)
+	delete(c.defaultConfig, lower)
+	delete(c.combinedConfig, lower)
+	c.mutex.Unlock()
+}
+
 func (c *ConfigManager) SetDefault(key string, value any) {
 	c.mutex.Lock()
 	defer c.mutex.Unlock()