Flagsmith SDK for Flutter

Flagsmith allows you to manage feature flags and remote config across multiple projects, environments and organisations.

The SDK for Flutter applications for https://flagsmith.com/.

Getting Started

The client library is available from the https://pub.dev:

dependencies:
  flagsmith: <latest>

Usage

Retrieving feature flags for your project

For full documentation visit https://docs.flagsmith.com/

Sign Up and create an account at https://flagsmith.com/

In your application, initialise the BulletTrain client with your API key:

final flagsmithClient = FlagsmithClient(
        apiKey: 'YOUR_ENV_API_KEY' 
        config: config, 
        seeds: <Flag>[
            Flag.seed('feature', enabled: true),
        ],
    );
await flagsmithClient.getFeatureFlags(reload: true) // fetch updates from api

if you prefer async initialization then you should use

final flagsmithClient = await FlagsmithClient.init(
        apiKey: 'YOUR_ENV_API_KEY',
        config: config, 
        seeds: <Flag>[
            Flag.seed('feature', enabled: true),
        ], 
        update: false,
    );
await flagsmithClient.getFeatureFlags(reload: true) // fetch updates from api

To check if a feature flag exists and is enabled:

bool featureEnabled = await flagsmithClient.hasFeatureFlag("my_test_feature");
if (featureEnabled) {
    // run the code to execute enabled feature
} else {
    // run the code if feature switched off
}

To get the configuration value for a feature flag:

final myRemoteConfig = await flagsmithClient.getFeatureFlagValue("my_test_feature");
if (myRemoteConfig != null) {
    // run the code to use remote config value
} else {
    // run the code without remote config
}

Cached flags

You can use caches instead of async/await

final config = FlagsmithConfig(
    baseURI: 'http://yoururl.com/',
    connectTimeout: 200,
    receiveTimeout: 500,
    sendTimeout: 500,
    storeType = StoreType.inMemory,
    caches: true, // mandatory if you want to use caches
);

final flagsmithClient = await FlagsmithClient.init(
        apiKey: 'YOUR_ENV_API_KEY', 
        config: config, 
        seeds: <Flag>[
            Flag.seed('feature', enabled: true),
        ], 
    );

await flagsmithClient.getFeatureFlags(reload: true); // fetch updates from api
bool isFeatureEnabled = flagsmithClient.hasCachedFeatureFlag('feature');

Identifying users

Identifying users allows you to target specific users from the Flagsmith dashboard.

To check if a feature exists for a given user Identity:

final user = FeatureUser(identifier: 'flagsmith_sample_user');
bool featureEnabled = await flagsmithClient.hasFeatureFlag('my_test_feature', user: user);
if (featureEnabled) {
    // run the code to execute enabled feature for given user
} else {
    // run the code when feature switched off
}

To get the configuration value for a feature flag for given a user Identity:

final myRemoteConfig = await flagsmithClient.getFeatureFlagValue('my_test_feature', user: user);
if (myRemoteConfig != null) {
    // run the code to use remote config value
} else {
    // run the code without remote config
}

To get the user traits for given user Identity:

final userTraits = await flagsmithClient.getTraits(user)
if (userTraits != null && userTraits) {
    // run the code to use user traits
} else {
    // run the code without user traits
}

To get user trait for given user Identity and specific Trait key:

final userTrait = await flagsmithClient.getTrait(user, 'cookies_key');
if (userTrait != null) {
    // run the code to use user trait
} else {
    // run the code without user trait
}

Or get user traits for given user Identity and specific Trait keys:

final userTraits = await flagsmithClient.getTraits(user, keys: ['cookies_key', 'other_trait']);
if (userTraits != null) {
    // run the code to use user traits
} else {
    // run the code without user traits
}

To update a user trait for given user Identity:

final userTrait = await flagsmithClient.getTrait(user, 'cookies_key');
if (userTrait != null) {
    // update value for user trait
    var updatedTrait = userTrait.copyWith(value: 'new value');
    Trait updated = await flagsmithClient.updateTrait(user, updatedTrait);
} else {
    // run the code without user trait
}

Override default configuration

By default, the client uses the default configuration. You can override this configuration as follows:

final flagsmithClient = FlagsmithClient(
      config: FlagsmithConfig(
          baseURI: 'http://yoururl.com/'
      ), apiKey: 'YOUR_ENV_API_KEY');

Override the default configuration with your own:

final flagsmithClient = FlagsmithClient(
      config: FlagsmithConfig(
          baseURI: 'http://yoururl.com/',
          connectTimeout: 200,
          receiveTimeout: 500,
          sendTimeout: 500,
          storeType = StoreType.inMemory,
          caches: true,
      ), apiKey: 'YOUR_ENV_API_KEY');

Getting Help

If you encounter a bug or feature request we would like to hear about it. Before you submit an issue please search existing issues in order to prevent duplicates.

Get in touch

If you have any questions about our projects you can email printeastwoodcz@gmail.com.

Libraries

flagsmith
Flagsmith SDK for Flutter [...]