Added: Reload and AutoReload functions

.gitignore

@@ -16,3 +16,5 @@
 # Dependency directories (remove the comment below to include it)
 # vendor/
 
+# Example test related files
+example*

README.md

@@ -7,7 +7,7 @@
 
 This package was made, to easily get needed settings from a file.
 
-- Supported file types are: **'json'** and **'yaml'**.
+- Supported file types are: **'json'**, **'yaml'** and **'ini'**.
 - The configuration keys are **case insensitive**.
 
 This package uses [github.com/spf13/viper](https://github.com/spf13/viper)
@@ -20,8 +20,10 @@ This package uses [github.com/spf13/viper](https://github.com/spf13/viper)
    * [Initialize settings from a given content](#initialize-settings-from-a-given-content)
    * [Get all keys from the settings](#get-all-keys-from-the-settings)
    * [Get all settings](#get-all-settings)
-   * [Add prefix](#add-prefix)
+   * [Add a sub tree](#add-a-sub-tree)
    * [Type assertions](#type-assertions)
+   * [Reload the settings data manually](#reload-the-settings-data-manually)
+   * [Automatic reload the settings data in the background](#automatic-reload-the-settings-data-in-the-background)
 
 ## Example usage
 
@@ -62,7 +64,7 @@ other:
     string: 'text'
     bool: true
 `
-sm := settings.New(NewFromSource)
+sm := settings.NewFromContent(content)
 ```
 
 [Back to top](#table-of-contents)
@@ -79,16 +81,15 @@ other:
     string: 'text'
     bool: true
 `
-sm := settings.New(NewFromSource)
+sm := settings.NewFromContent(content)
 keys, err := sm.GetAllKeys()
 if err != nil {
     log.Fatal(err)
 }
 
-log.Println("keys", keys)
-
 // Output:
 // 2020/01/29 19:09:52 keys [other content.int content.string content.bool]
+log.Println("keys", keys)
 ```
 
 [Back to top](#table-of-contents)
@@ -105,24 +106,23 @@ other:
     string: 'text'
     bool: true
 `
-sm := settings.New(NewFromSource)
+sm := settings.NewFromContent(content)
 allSettings, err := sm.GetAllSettings()
 if err != nil {
     log.Fatal(err)
 }
 
-log.Println("allSettings", allSettings)
-
 // Output:
 // 2020/01/29 19:11:58 allSettings map[content:map[bool:true int:1 string:text]]
+log.Println("allSettings", allSettings)
 ```
 
 [Back to top](#table-of-contents)
 
-### Add prefix
+### Add a sub tree
 
 Returning a new settings instance representing a sub tree of this instance.
-AddPrefix is case-insensitive for a key.
+SubTree is case-insensitive for a key.
 
 ```go
 var content = `
@@ -132,15 +132,17 @@ a:
       value: 1
 `
 
-sm := settings.NewFromSource(content)
+sm := settings.NewFromContent(content)
 
-sm = sm.AddPrefix("a.b")
+sm = sm.SubTree("a.b")
 
 intValue, err := sm.GetInt("c.value")
 if err != nil {
     log.Fatal(err)
 }
 
+// Output:
+// 2020/02/02 15:52:55 allSettings 1
 log.Println("allSettings", intValue)
 ```
 
@@ -165,3 +167,116 @@ timeDurationKey, err := sm.GetDuration("time.duration.key")
 ```
 
 [Back to top](#table-of-contents)
+
+### Reload the settings data manually
+
+Re-read the settings data by calling the Reload function.
+
+```go
+content := `
+config:
+  config_key:  config_value`
+
+err := ioutil.WriteFile("./example/settings/example_config.yaml", []byte(content), os.ModePerm)
+if err != nil {
+    log.Fatal(err)
+}
+
+sm := settings.New("./example/settings/example_config.yaml")
+
+v, err := sm.Get("config.config_key")
+if err != nil {
+    log.Fatal(err)
+}
+
+// Output:
+// 2020/02/02 15:31:58 config_value
+log.Println(v)
+
+content = strings.ReplaceAll(content, "config_key:  config_value", "foo:  bar")
+err = ioutil.WriteFile("./example/settings/example_config.yaml", []byte(content), os.ModePerm)
+if err != nil {
+    log.Fatal(err)
+}
+
+// Reload the configuration ...
+sm.Reload()
+
+v, err = sm.Get("config.foo")
+if err != nil {
+    log.Fatal(err)
+}
+
+// Output:
+// 2020/02/02 15:31:58 bar
+log.Println(v)
+```
+
+[Back to top](#table-of-contents)
+
+### Automatic reload the settings data in the background
+
+AutoReload is watching for settings file changes in the background and reloads configuration if needed.
+
+```go
+content := `
+config:
+  config_key:  config_value`
+
+err := ioutil.WriteFile("./example/settings/example_config.yaml", []byte(content), os.ModePerm)
+if err != nil {
+    log.Fatal(err)
+}
+
+sm := settings.New("./example/settings/example_config.yaml")
+
+// Activate the automatic reload function ...
+sm.AutoReload()
+
+v, err := sm.Get("config.config_key")
+if err != nil {
+    log.Fatal(err)
+}
+
+// Output:
+// 2020/02/02 15:42:49 config_value
+log.Println(v)
+
+content = strings.ReplaceAll(content, "config_key:  config_value", "foo:  bar")
+err = ioutil.WriteFile("./example/settings/example_config.yaml", []byte(content), os.ModePerm)
+if err != nil {
+    log.Fatal(err)
+}
+
+time.Sleep(5 * time.Millisecond)
+
+v, err = sm.Get("config.foo")
+if err != nil {
+    log.Fatal(err)
+}
+
+// Output:
+// 2020/02/02 15:42:49 settings.AutoReload settings reloaded
+// 2020/02/02 15:42:49 bar
+log.Println(v)
+
+content = strings.ReplaceAll(content, "foo:  bar", "config_key:  config_value")
+err = ioutil.WriteFile("./example/settings/example_config.yaml", []byte(content), os.ModePerm)
+if err != nil {
+    log.Fatal(err)
+}
+
+time.Sleep(5 * time.Millisecond)
+
+v, err = sm.Get("config.config_key")
+if err != nil {
+    log.Fatal(err)
+}
+
+// Output:
+// 2020/02/02 15:42:49 settings.AutoReload settings reloaded
+// 2020/02/02 15:42:49 config_value
+log.Println(v)
+```
+
+[Back to top](#table-of-contents)