---
title: OptimizelyConfig for the Flutter SDK
slug: feature-experimentation/docs/optimizelyconfig-flutter
docTags: 
createdAt: 2026-08-05T20:40:02.000Z
---

Optimizely Feature Experimentation SDKs open a well-defined set of public APIs, hiding implementation details. However, you may need access to project configuration data within the [datafile](docId:3LmHm4b3kTxKBuoR93KN8). The following section extends the public APIs to define data models and access methods, which you can use to access project configuration data.

## Version

1.0.1 or higher

A public configuration data model (OptimizelyConfig) is defined as a structured format of static Optimizely Project data.

### Get `OptimizelyConfig`

You can access `OptimizelyConfig` from `OptimizelyClient` (top-level) with this public API call.

```dart
Future<OptimizelyConfigResponse> getOptimizelyConfig();
```

`getOptimizelyConfig` returns an `OptimizelyConfigResponse` containing `optimizelyConfig` instance which includes the following:

- Environment key
- SDK key
- Datafile revision number
- Experiments mapped by key values
- All attributes
- All audiences
- All events
- Feature flags mapped by key values

:::hint{type="info"}
When the system updates the datafile, you can add a [OptimizelyConfigUpdate notification listener](#)  to get notified. After receiving the notification, call the method to get the updated `OptimizelyConfig` data.
:::

### Get datafile

To share the same datafile between multiple SDK instances, such as in a client or server scenario, pass a JSON string representation of the config (the datafile) between instances. To get the datafile, use the `OptimizelyConfig` object's `datafile` key. For information, see [Sharing the datafile with multiple SDK implementations](docId\:eH-UMm_rOn_GdGDGLV6__).

### Object model

The following shows the object model for `OptimizelyConfig`:

```dart
// OptimizelyConfig is an object describing the current project configuration data
class OptimizelyConfig {

  // This experimentsMap is for experiments of legacy projects only.
  // For flag projects, experiment keys are not guaranteed to be unique 
  // across multiple flags, so this map may not include all experiments 
  // when keys conflict.
  Map<String, OptimizelyExperiment> experimentsMap = {};
  Map<String, OptimizelyFeature> featuresMap = {};
  List<OptimizelyAttribute> attributes = [];
  List<OptimizelyEvent> events = [];
  List<OptimizelyAudience> audiences = [];
  String? revision;
  String? sdkKey;
  String? environmentKey;
  String? datafile;
}

// OptimizelyFeature is an object describing a feature flag
class OptimizelyFeature {
  final String? id;
  final String? key;
  final List<OptimizelyExperiment> deliveryRules;
  final List<OptimizelyExperiment> experimentRules;
}

// OptimizelyExperiment is an object describing an experiment
class OptimizelyExperiment {
  final String? id;
  final String? key;
  final String audiences;
  final Map<String, OptimizelyVariation> variationsMap;
}

// OptimizelyVariation is an object describing a variation
class OptimizelyVariation {
  final String? id;
  final String? key;
  final bool featureEnabled;
  final Map<String, OptimizelyVariable> variablesMap;
}

// OptimizelyVariable is an object describing a Variable
class OptimizelyVariable {
  final String? id;
  final String? key;
  final String? type;
  final String? value;
}

// OptimizelyAttribute is an object describing an Attribute
class OptimizelyAttribute {
  final String? id;
  final String? key;
}

// OptimizelyAudience is an object describing an Audience
class OptimizelyAudience {
  final String? id;
  final String? name;
  final String? conditions;
}

// OptimizelyEvent is an object describing an Event
class OptimizelyEvent {
  final String? id;
  final String? key;
  final List<String> experimentIds;
}
```

## Examples

You can access `OptimizelyConfig` from the `OptimizelyClient` (top-level) using the following code example:

```dart
  var configResponse = await flutterSDK.getOptimizelyConfig();
  var optimizelyConfig = configResponse.optimizelyConfig!;

  print("Optimizely [OptimizelyConfig] revision = ${optimizelyConfig.revision}");
  print("Optimizely [OptimizelyConfig] sdkKey = ${optimizelyConfig.sdkKey}");
  print("Optimizely [OptimizelyConfig] environmentKey = ${optimizelyConfig.environmentKey}");

  print("Optimizely [OptimizelyConfig] attributes = ${optimizelyConfig.attributes}");
  var attributes = optimizelyConfig.attributes;
  for (var attribute in attributes) {
    print("Optimizely [OptimizelyAttribute]  -- (id, key) = ${attribute.id}, ${attribute.key}");
  }

  print("Optimizely [OptimizelyConfig] audiences = ${optimizelyConfig.audiences}");
  var audiences = optimizelyConfig.audiences;
  for (var audience in audiences) {
    print("Optimizely [OptimizelyAudience]  -- (id, key, conditions) = ${audience.id}, ${audience.name}, ${audience.conditions.toString()}");
  }

  print("Optimizely [OptimizelyConfig] events = ${optimizelyConfig.events}");
  var events = optimizelyConfig.events;
  for (var event in events) {
    print("Optimizely [OptimizelyEvent]  -- (id, key, experimentIds) = ${event.id}, ${event.key}, ${event.experimentIds.toString()}");
  }

// all features
  var featuresMap = optimizelyConfig.featuresMap;
  for (var flagKey in featuresMap.keys) {
    var flag = featuresMap[flagKey];
    var experimentRules = flag?.experimentRules;
    for (var experiment in experimentRules!) {
      print("Optimizely [OptimizelyExperiment]  -- Experiment Rule Key: ${experiment.key}");
      print("Optimizely [OptimizelyExperiment]  -- Experiment Audiences: ${experiment.audiences}");

      var variationsMap = experiment.variationsMap;
      for (var variationKey in variationsMap.keys) {
        var variation = variationsMap[variationKey];
        print("Optimizely [OptimizelyVariation]    -- variation = { key: ${variationKey}, id: ${variation?.id}, featureEnabled: ${variation?.featureEnabled}");
        // use variation data here...

        var optimizelyVariableMap = variation?.variablesMap;
        for (var variableKey in optimizelyVariableMap!.keys) {
          var variable = optimizelyVariableMap[variableKey];
          print("Optimizely [OptimizelyVariable]      -- variable = key: ${variableKey}, value: ${variable!.value}");
          // use variable data here...

        }
      }
    }
  var deliveryRules = flag!.deliveryRules;
  for (var delivery in deliveryRules) {
    print("Optimizely [OptimizelyExperiment]  -- Delivery Rule Key: ${delivery.key}");
    print("Optimizely [OptimizelyExperiment]  -- Delivery Audiences: ${delivery.audiences.toString()}");
  }

// use experiments and other feature flag data here...
}

// listen to OPTIMIZELY_CONFIG_UPDATE to get updated data
flutterSDK.addConfigUpdateNotificationListener((msg) {
  var newConfig = flutterSDK.getOptimizelyConfig();
});
```