- Add mutable configuration provider

- Split tests file
- Fixed and nullable functions
- Able to set or remove config from system config

lib/configurable.dart

@@ -2,8 +2,16 @@ library configurable;
 
 import 'package:configurable/system_config.dart';
 
+/// get config or null from system config
 String? getConfigOrNull(String key, {String? defaultValue}) =>
     SystemConfig.getOrNull(key, defaultValue: defaultValue);
+
+/// get config with non-null from system config
 String getConfig(String key, {String? defaultValue}) =>
     SystemConfig.get(key, defaultValue: defaultValue);
+
+/// check has config key or not from system config
 bool hasConfigkey(String key) => SystemConfig.containsKey(key);
+
+/// set config into memory
+void setConfig(String key, String? value) => SystemConfig.set(key, value);

lib/configuration_provider.dart

@@ -1,4 +1,11 @@
+/// Configuration Provider
+///
+/// @author sombochea
+/// @since 1.0.0
 abstract class ConfigurationProvider {
+  /// check has key or not in implemented classes
   bool containsKey(String key);
+
+  /// get or null in implemented classes
   String? getOrNull(String key, {String? defaultValue});
 }

lib/dotenv/dotenv_parser.dart

@@ -1,5 +1,9 @@
 part of dotenv;
 
+/// Dotenv Parser
+///
+/// @author sombochea
+/// @since 1.0.0
 class DotenvParser {
   static const _singleQuot = "'";
   static const _keyword = 'export';
@@ -8,9 +12,10 @@ class DotenvParser {
   static final _surroundQuotes = RegExp(r'''^(['"])(.*)\1$''');
   static final _bashVar = RegExp(r'(?:\\)?(\$)(?:{)?([a-zA-Z_][\w]*)+(?:})?');
 
-  // constructor for parser
+  /// constructor for parser
   const DotenvParser();
 
+  /// Parse the env lines into map values and return it back
   Map<String, String> parse(Iterable<String> lines) {
     var out = <String, String>{};
     lines.forEach((line) {
@@ -73,11 +78,14 @@ class DotenvParser {
   @visibleForTesting
   String swallow(String line) => line.replaceAll(_keyword, '').trim();
 
+  /// Check key is valid or not
   bool _isValid(String s) => s.isNotEmpty && s.contains('=');
 
+  /// Has key in map values
   bool _has(Map<String, String> map, String key) =>
       map.containsKey(key) && map[key] != null;
 
+  /// Try to check on platform env
   String? _tryPlatformEnv(String key) {
     if (!_has(Platform.environment, key)) {
       return '';

lib/dotenv_configuration_provider.dart

@@ -1,7 +1,12 @@
 import 'package:configurable/configuration_provider.dart';
 import 'package:configurable/dotenv/dotenv.dart' show env, load;
 
+/// Dotenv Configuration Provider
+///
+/// @author sombochea
+/// @since 1.0.0
 class DotenvConfigurationProvider implements ConfigurationProvider {
+  /// default constructor to load the platform environment
   DotenvConfigurationProvider() {
     load();
   }
@@ -15,6 +20,7 @@ class DotenvConfigurationProvider implements ConfigurationProvider {
   String? getOrNull(String key, {String? defaultValue}) {
     var value = env[key];
 
+    /// if value is null, then return default value
     if (value == null) {
       return defaultValue;
     }

lib/mutable_configurable_provider.dart

@@ -0,0 +1,19 @@
+import 'package:configurable/configuration_provider.dart';
+
+/// Mutable Configuration Provider
+///
+/// @author sombochea
+/// @since 1.0.3
+abstract class MutableConfigurationProvider implements ConfigurationProvider {
+  /// Allow to set the value into config values
+  void set(String key, String? value);
+
+  /// Allow to set all values into config values
+  void setAll(Map<String, String?> configs);
+
+  /// Allow to remove the key from config values
+  void remove(String key);
+
+  /// Allow to remove all values from config values
+  void removeAll();
+}

lib/simple_configuration_provider.dart

@@ -1,12 +1,17 @@
-import 'package:configurable/configuration_provider.dart';
+import 'package:configurable/mutable_configurable_provider.dart';
 
-class SimpleConfigurationProvider implements ConfigurationProvider {
+/// Simple Configuration Provider
+///
+/// @author sombochea
+/// @since 1.0.0
+class SimpleConfigurationProvider implements MutableConfigurationProvider {
   Map<String, String?> configs = {};
 
   @override
   String? getOrNull(String key, {String? defaultValue}) {
     var value = configs[key];
 
+    /// if value is null, then set the default value and return it back
     if (value == null) {
       configs[key] = defaultValue;
       return defaultValue;
@@ -19,4 +24,24 @@ class SimpleConfigurationProvider implements ConfigurationProvider {
   bool containsKey(String key) {
     return configs.containsKey(key);
   }
+
+  @override
+  void set(String key, String? value) {
+    configs[key] = value;
+  }
+
+  @override
+  void remove(String key) {
+    configs.remove(key);
+  }
+
+  @override
+  void removeAll() {
+    configs.clear();
+  }
+
+  @override
+  void setAll(Map<String, String?> configs) {
+    configs.addAll(configs);
+  }
 }

lib/system_config.dart

@@ -1,19 +1,25 @@
 import 'package:configurable/configuration_provider.dart';
+import 'package:configurable/mutable_configurable_provider.dart';
 import 'package:configurable/simple_configuration_provider.dart';
 
+/// System Configuration Static Functions
+///
+/// @author sombochea
+/// @since 1.0.0
 class SystemConfig {
-  static ConfigurationProvider? provider;
+  static ConfigurationProvider? _provider;
 
+  /// Set configuration provider
   static void setProvider(ConfigurationProvider provider) {
-    SystemConfig.provider = provider;
+    _provider = provider;
   }
 
   static ConfigurationProvider getProvider() {
-    if (provider == null) {
+    if (_provider == null) {
       setProvider(SimpleConfigurationProvider());
     }
 
-    return provider!;
+    return _provider!;
   }
 
   static String get(String key, {String? defaultValue}) {
@@ -25,4 +31,22 @@ class SystemConfig {
   }
 
   static bool containsKey(String key) => getProvider().containsKey(key);
+
+  /// Convert to mutable configuration provider
+  static MutableConfigurationProvider _getMutableConfigurationProvider() {
+    if (_provider is MutableConfigurationProvider) {
+      return (_provider as MutableConfigurationProvider);
+    } else {
+      throw Exception(
+          'Error cannot use mutable functions without mutable configuration provider!');
+    }
+  }
+
+  static void set(String key, String? value) {
+    _getMutableConfigurationProvider().set(key, value);
+  }
+
+  static void setAll(Map<String, String?> values) {
+    _getMutableConfigurationProvider().setAll(values);
+  }
 }