Flutter App Environment

A simple solution to manage environment variables using .json files or configuration in the entrypoint file.

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Links

• See CHANGELOG.md for major/breaking updates.
• Check out the Example for a detailed explanation of all features.

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Installation

To install the package, run the following command:

flutter pub add --dev flutter_app_environment

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Managing Environment Variables from a .json File

Requirements

Before initializing the environment, ensure the following:

WidgetsFlutterBinding.ensureInitialized();

Add the configuration files path to pubspec.yaml:

flutter:
  assets:
    - res/config/

• For EnvironmentType.development, use development.json as the configuration file.
• For EnvironmentType.test, use test.json as the configuration file.
• For EnvironmentType.production, use production.json as the configuration file.

Usage: Three Simple Steps

1. Create the Config

   @JsonSerializable(createToJson: false)
   class EnvironmentConfig {
     const EnvironmentConfig({
       required this.title,
       required this.initialCounter,
     });
   
     factory EnvironmentConfig.fromJson(Map<String, dynamic> json) =>
         _$EnvironmentConfigFromJson(json);
   
     final String title;
     final int initialCounter;
   }

2. Initialize the Environment

   WidgetsFlutterBinding.ensureInitialized();
   
   await Environment.initFromJson<EnvironmentConfig>(
     environmentType: EnvironmentType.development,
     fromJson: EnvironmentConfig.fromJson,
   );

3. Use the Config

   home: HomePage(
     title: Environment<EnvironmentConfig>.instance().config.title,
   ),

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Managing Environment Variables from the Entrypoint File

Usage: Three Simple Steps

1. Create the Config (same as the previous example)

2. Initialize the Environment

   WidgetsFlutterBinding.ensureInitialized();
   
   Environment.init<EnvironmentConfig>(
     environmentType: EnvironmentType.test,
     config: const EnvironmentConfig(
       title: 'Test environment title',
       initialCounter: 0,
     ),
   );

3. Use the Config

   home: HomePage(
     title: Environment<EnvironmentConfig>.instance().config.title,
   ),

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Managing Environment Variables with Custom Types

1. Create a Custom Environment Type

   enum CustomEnvironmentType { dev, stage, prod }

2. Initialize with a JSON Config

   await Environment.initFromJsonWithCustomType<EnvironmentConfig, CustomEnvironmentType>(
     environmentType: CustomEnvironmentType.stage,
     fromJson: EnvironmentConfig.fromJson,
   );

3. Initialize from the Entrypoint File

   Environment.initWithCustomType<EnvironmentConfig, CustomEnvironmentType>(
     environmentType: CustomEnvironmentType.dev,
     config: const EnvironmentConfig(
       title: 'Custom environment title',
       initialCounter: 0,
     ),
   );

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Example Project Structure

For a better understanding, here's an example of how your project structure might look when handling environment variables:

your_project/
│
├── res/
│   └── config/
│       ├── development.json
│       ├── test.json
│       └── production.json
│
├── lib/
│   ├── main.dart
│   └── environment_config.dart
│
└── pubspec.yaml

In this example, JSON configuration files are stored in the res/config/ folder and declared in pubspec.yaml. The environment configuration is loaded in main.dart and used throughout the app.

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Notes

• Make sure to call WidgetsFlutterBinding.ensureInitialized() before initializing the environment.
• The EnvironmentConfig class should match the structure of your .json files or entrypoint configurations.
• You can switch between different environment types depending on your build (development, test, production) or create custom environment types.

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Contribute

Feel free to fork, improve, submit pull requests, or report issues. I’ll be happy to fix bugs or enhance the extension based on your feedback.

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License

This project is licensed under the MIT License. See the LICENSE file for more details.