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React SDK

With the Kameleoon React SDK, you can run feature experiments and activate feature flags on your front-end web and mobile application. Integrating our SDK into your web and mobile application is easy, and its footprint (memory and network usage) is low.

Getting started: For help getting started, see the developer guide

Changelog: Details on the latest version of the React SDK can be found in the changelog.

SDK methods: For the full reference documentation of the React SDK, see the reference section.

Requirements: React SDK requires React 16.8.0+

Developer guide​

Follow this section to integrate the SDK into your application and learn more about using the SDK.

Getting started​

This section walks you through installing and configurating the SDK for the first time.

Installation​

The Kameleoon SDK Installation tool is the preferred way to install the SDK. This SDK Installer helps you to install the SDK of your choice, generate a basic code sample, and configure external dependencies if needed.

To start the SDK Installation tool, install and run it globally:

npm install --global @kameleoon/sdk-installer
kameleoon-sdk

Or run it directly with npx:

npx @kameleoon/sdk-installer

Create the Kameleoon Client​

To get started to create an entry point for React SDK by creating Kameleoon Client on the top level of your application. Create an instance of KameleoonClient using the createClient() function, imported from the kameleoon package.

import {
  createClient,
  Environment,
  SDKConfigurationType,
} from '@kameleoon/react-sdk';

// -- Optional configuration
const configuration: Partial<SDKConfigurationType> = {
  updateInterval: 60,
  environment: Environment.Production,
  domain: '.example.com',
};

const client = createClient({ siteCode: 'my_site_code', configuration });

Wrap the application in the Kameleoon Provider​

The second step is connecting the previously created Kameleoon Client to KameleoonProvider by passing the configured client to KameleoonProvider:

import {
  createClient,
  Environment,
  KameleoonProvider,
} from '@kameleoon/react-sdk';

const client = createClient({
  siteCode: 'my_site_code',
  configuration: {
    updateInterval: 60,
    environment: Environment.Production,
  },
});

function AppWrapper(): JSX.Element {
  return (
    <KameleoonProvider client={client}>
      <App />
    </KameleoonProvider>
  );
}
KameleoonProvider​

Use this provider on root level by wrapping your app to gain an access to KameleoonClient. This ensures your app does not flicker due to flag changes at startup time.

Props​
NameTypeDescription
children (required)ReactNodechild elements of the provider
client (required)KameleoonClientKameleoonClient instance created by createClient()

Await for the client initialization​

KameleoonClient initialization is done asynchronously in order to make sure that Kameleoon API call was successful for that hook useInitialize is used. You can use async/await, Promise.then() or any other method to handle asynchronous client initialization.

import { useEffect, useCallback } from 'react';
import { useInitialize } from '@kameleoon/react-sdk';

function MyComponent(): JSX.Element {
  const { initialize } = useInitialize();

  // -- Waiting for the client initialization using `async/await`

  const init = useCallback(async (): Promise<void> => {
    await initialize();
  }, [initialize]);

  useEffect(() => {
    init();
  }, [init]);
}

Activating a feature flag​

Assigning a unique ID to a user​

To assign a unique ID to a user, you can use the getVisitorCode() method. If a visitor code doesn’t exist (from the request headers cookie), the method generates a random unique ID or uses a defaultVisitorCode that you would have generated. The ID is then set in a response headers cookie.

If you are using Kameleoon in Hybrid mode, calling the getVisitorCode() method ensures that the unique ID (visitorCode) is shared between the application file (kameleoon.js) and the SDK.

Retrieving a flag configuration​

To implement a feature flag in your code, you must first create a feature flag in your Kameleoon account.

To determine if a feature flag is active for a specific user, you need to retrieve its configuration. Use the getFeatureFlagVariationKey() or isFeatureFlagActive() method to retrieve the configuration based on the featureKey.

The isFeatureFlagActive() method can be used if you want to retrieve the configuration of a simple feature flag that has only an ON or OFF state, as opposed to more complex feature flags with multiple variations or targeting options.3

The getFeatureFlagVariationKey() method retrieves the configuration of a feature experiment with several feature variations. You can use the method to get a variation key for a given user by providing the visitorCode and featureKey as mandatory arguments.

Feature flags can have associated variables that are used to customize their behavior. To retrieve these variables, use the getFeatureFlagVariables() method. This method checks whether the user is targeted, finds the visitor’s assigned variation, saves it to storage, and sends a tracking request.

note

To check if a feature flag is active, you only need to use one method. Choose isFeatureFlagActive if you simply want to know if a feature flag is on or off. For more complex scenarios, like dynamically changing the feature's behavior, use getFeatureFlagVariables.

Adding data points to target a user or filter / breakdown visits in reports​

To target a user, ensure you’ve added relevant data points to their profile before retrieving the feature variation or checking if the flag is active. Use the addData() method to add these data points to the user’s profile.

To retrieve data points that have been collected on other devices or to access past data points about a user (which would have been collected client-side if you are using Kameleoon in Hybrid mode), use the getRemoteVisitorData() method. This method asynchronously fetches data from our servers. However, it is important you call getRemoteVisitorData() before retrieving the variation or checking if the feature flag is active, as this data might be required to assign a user to a given variation of a feature flag.

To learn more about available targeting conditions, read our detailed article on the subject.

Additionally, the data points you add to the visitor profile will be available when analyzing your experiments, allowing you to filter and break down your results by factors like device and browser. Kameleoon Hybrid mode automatically collects a variety of data points on the client-side, making it easy to break down your results based on these pre-collected data points. See the complete list here.

If you need to track additional data points beyond what's automatically collected, you can use Kameleoon's Custom Data feature. Custom Data allows you to capture and analyze specific information relevant to your experiments. To ensure your results are accurate, it's recommended to filter out bots by using the userAgent data type. You can learn more about this here. Don't forget to call the flush() method to send the collected data to Kameleoon servers for analysis.

Tracking flag exposition and goal conversions​

Kameleoon will automatically track visitors’ exposition to flags as soon as you call one of these methods:

  • getFeatureFlagVariationKey()
  • getFeatureFlagVariable()
  • getFeatureFlagVariables()
  • isFeatureFlagActive()

When a user completes a desired action (for example, making a purchase), it counts as a conversion. To track conversions, you must use the trackConversion() method, and provide the visitorCode and goalId parameters.

Sending events to analytics solutions​

To track conversions and send exposure events to your customer analytics solution, you must first implement Kameleoon in Hybrid mode. Then, use the getEngineTrackingCode() method.

The getEngineTrackingCode method retrieves the unique tracking code required to send exposure events to your analytics solution. Using this method allows you to record events and send them to your desired analytics platform.

React Native considerations​

note

React Native on android platform doesn't support Real Time Update feature.

While React SDK works the same way in both React Native and React contexts, it's important to note that setup steps differ. Due to the lack of browser API in React Native, React SDK has to have different external dependency implementations to work correctly. For that, Kameleoon provides several dedicated npm packages that you can install and set up manually or install using Kameleoon SDK Installation Tool (recommended).

The packages include:

  • @kameleoon/react-native-storage - built using react-native-mmkv library
  • @kameleoon/react-native-event-source - built using react-native-event-source-ts library
  • @kameleoon/react-native-visitor-code-manager - built on top of react-native-mmkv library
  • optional @kameleoon/react-native-secure-prng - built using react-native-get-random-values library

If you don't want to use the listed packages, you can provide your own implementation following the external dependencies guide.

Example React SDK setup for React Native application:

import { createClient } from '@kameleoon/react-sdk';
import { KameleoonEventSource } from '@kameleoon/react-native-event-source';
import { KameleoonStorage } from '@kameleoon/react-native-storage';
import { KameleoonVisitorCodeManager } from '@kameleoon/react-native-visitor-code-manager';
import { KameleoonSecurePRNG } from '@kameleoon/react-native-secure-prng';

// --- Create KameleoonClient ---
const client = createClient({
  siteCode: 'my_site_code',
  externals: {
    storage: new KameleoonStorage(),
    eventSource: new KameleoonEventSource(),
    visitorCodeManager: new KameleoonVisitorCodeManager(),
    // -- Optional --
    prng: new KameleoonSecurePRNG(),
  },
});

Targeting conditions​

The Kameleoon SDKs support a variety of predefined targeting conditions that you can use to target users in your campaigns. For the list of conditions supported by this SDK, see use visit history to target users.

You can also use your own external data to target users.

Logging​

The SDK generates logs to reflect various internal processes and issues.

Log levels​

The SDK supports configuring limiting logging by a log level.

import { KameleoonClient, KameleoonLogger, LogLevel } from '@kameleoon/react-sdk';

const client = createClient({ siteCode: 'my_site_code', configuration });

// The `NONE` log level allows no logging.
client.setLogLevel(LogLevel.NONE);
// Or use directly KameleoonLogger
KameleoonLogger.setLogLevel(LogLevel.NONE);


// The `ERROR` log level allows to log only issues that may affect the SDK's main behaviour.
client.setLogLevel(LogLevel.ERROR);
// Or use directly KameleoonLogger
KameleoonLogger.setLogLevel(LogLevel.ERROR);

// The `WARNING` log level allows to log issues which may require an attention.
// It extends the `ERROR` log level.
// The `WARNING` log level is a default log level.
client.setLogLevel(LogLevel.WARNING);
// Or use directly KameleoonLogger
KameleoonLogger.setLogLevel(LogLevel.WARNING);

// The `INFO` log level allows to log general information on the SDK's internal processes.
// It extends the `WARNING` log level.
client.setLogLevel(LogLevel.INFO);
// Or use directly KameleoonLogger
KameleoonLogger.setLogLevel(LogLevel.INFO);

// The `DEBUG` log level allows to log extra information on the SDK's internal processes.
// It extends the `INFO` log level.
client.setLogLevel(LogLevel.DEBUG);
// Or use directly KameleoonLogger
KameleoonLogger.setLogLevel(LogLevel.DEBUG);

Custom handling of logs​

The SDK writes its logs to the console output by default. This behaviour can be overridden.

note

Logging limiting by a log level is performed apart from the log handling logic.

import { KameleoonClient, KameleoonLogger, IExternalLogger, LogLevel } from '@kameleoon/react-sdk';

export class CustomLogger implements IExternalLogger {
  // `log` method accepts logs from the SDK
  public log(level: LogLevel, message: string): void {
    // Custom log handling logic here. For example:
    switch (level) {
      case LogLevel.DEBUG:
        console.debug(message);
        break;
      case LogLevel.INFO:
        console.info(message);
        break;
      case LogLevel.WARNING:
        console.warn(message);
        break;
      case LogLevel.ERROR:
        console.error(message);
        break;
    }
  }
}

const client = createClient({
  siteCode: 'my_site_code',
  externals: {
    logger: new CustomLogger(),
  },
});

// Log level filtering is applied separately from log handling logic.
// The custom logger will only accept logs that meet or exceed the specified log level.
// Ensure the log level is set correctly.
client.setLogLevel(LogLevel.DEBUG);
// Or use directly KameleoonLogger
KameleoonLogger.setLogLevel(LogLevel.DEBUG);

Domain information​

You provide a domain as the domain in KameleoonClient [configuration], which is used for storing Kameleoon visitor code in cookies. This is important when working with the getVisitorCode and setLegalConsent methods. The domain you provide is stored in the cookie as the Domain= key.

Setting the domain​

The domain you provide indicates the URL address can use the cookie. For example, if your domain is www.example.com. the cookie is only available from a www.example.com URL. That means that pages with the app.example.com domain can't use the cookie.

To be more flexible around subdomains, you can prefix a domain with .. For example, the domain .example.com allows the cookie to function on both app.example.com and login.example.com.

note

You can't use regular expressions, special symbols, protocol, or port numbers in the domain. Additionally, a specific list of subdomains are not allowed to be used with the prefix ..

Here's a small domain cheat sheet:

DomainAllowed URLsDisallowed URLs
www.example.com✅www.example.com❌ app.example.com
✅ example.com❌ .com
.example.com = example.com✅ example.com❌ otherexample.com
✅ www.example.com
✅ app.example.com
✅ login.example.com
https://www.example.com⛔ bad domain⛔ bad domain
www.example.com:4408⛔ bad domain⛔ bad domain
.localhost.com = localhost⛔ bad domain⛔ bad domain

Developing on localhost​

localhost is always considered a bad domain, making it hard to test the domain when developing on localhost.

There are two ways to avoid this issue:

  • Don't specify the domain field in the SDK client while testing. This prevents localhost issues (the cookie will be set on any domain).
  • Create a local domain for localhost. For example:
    • Navigate to /etc/hosts on Linux or to c:\Windows\System32\Drivers\etc\hosts on Windows
    • Open hosts with file super user or administrator rights
    • Add a domain to the localhost port, for example: 127.0.0.1 app.com
    • Now you can run your app locally on app.com:{my_port} and specify .app.com as your domain

External dependencies​

SDK external dependencies use the dependency injection pattern to give you the ability to provide your own implementations for certain parts of an SDK.

note

In the React SDK, all external dependencies have default implementations, which use a native browser API so there's no need to provide them unless another API is required for specific use cases.

Here's the list of available external dependencies:

DependencyInterfaceRequired/OptionalAPI UsedDescription
storageIExternalStorageOptionalBrowser localStorageUsed for storing all the existing and collected SDK data
requesterIExternalRequesterOptionalBrowser fetchUsed for performing all the network requests
eventSourceIExternalEventSourceOptionalBrowser EventSourceUsed for receiving Server Sent Events for Real Time Update capabilities
visitorCodeManagerIExternalVisitorCodeManagerOptionalBrowser cookieUsed for storing and synchronizing visitor code
prngIExternalPRNGOptionalMath.random or Browser crypto.getRandomValuesUsed to generate unique IDs for tracking events
loggerILoggerOptionalCustom implementationUsed for custom handling of logs from the SDK. Allows to define how logs are processed and where they are output.

The following example implements external dependencies. To import an interface from an SDK, create a class that implements it and pass the instantiated class to the SDK.

Storage​

import { IExternalStorage } from '@kameleoon/react-sdk';

// --- External Storage implementation ---
// - JavaScript `Map` is used as an example storage
const storage = new Map();

class MyStorage<T> implements IExternalStorage<T> {
  public read(key: string): T | null {
    // - Read data using `key`
    const data = storage.get(key);

    // - Return `null` if there's no data
    if (!data) {
      return null;
    }

    // - Return obtained data
    return data;
  }

  public write(key: string, data: T): void {
    // - Write data using `key`
    storage.set(key, data);
  }
}

// --- Create KameleoonClient ---
const client = createClient({
  siteCode: 'my_site_code',
  externals: {
    storage: new MyStorage(),
  },
});

EventSource​

import {
  IExternalEventSource,
  EventSourceOpenParametersType,
} from '@kameleoon/react-sdk';

// --- External EventSource implementation ---
// - Example uses native browser `EventSource`
class MyEventSource implements IExternalEventSource {
  private eventSource?: EventSource;

  public open({
    eventType,
    onEvent,
    url,
  }: EventSourceOpenParametersType): void {
    // - Initialize `EventSource`
    const eventSource = new EventSource(url);

    this.eventSource = eventSource;
    // - Add event listener with provided event type and event callback
    this.eventSource.addEventListener(eventType, onEvent);
  }

  public close(): void {
    // - Cleanup open event source
    if (this.eventSource) {
      this.eventSource.close();
    }
  }

  public onError(callback: (error: Event) => void): void {
    // - Set error callback
    if (this.eventSource) {
      this.eventSource.onerror = callback;
    }
  }
}

// --- Create KameleoonClient ---
const client = createClient({
  siteCode: 'my_site_code',
  externals: {
    eventSource: new MyEventSource(),
  },
});

VisitorCodeManager​

import {
  IExternalVisitorCodeManager,
  SetDataParametersType,
  KameleoonUtils,
} from '@kameleoon/react-sdk';

// --- External Visitor Code Manager implementation ---
// - Example uses browser `document.cookie` API
class MyVisitorCodeManager implements IExternalVisitorCodeManager {
  public getData(key: string): string | null {
    const cookieString = document.cookie;

    // - Return `null` if no cookie was found
    if (!cookieString) {
      return null;
    }

    // - Parse cookie finding it by provided `key`
    return KameleoonUtils.getCookieValue(cookieString, key);
  }

  public setData({
    visitorCode,
    domain,
    maxAge,
    key,
    path,
  }: SetDataParametersType): void {
    // - Set cookie with provided parameters
    let resultCookie = `${key}=${visitorCode}; Max-Age=${maxAge}; Path=${path}`;

    if (domain) {
      resultCookie += `; Domain=${domain}`;
    }

    document.cookie = resultCookie;
  }
}

// --- Create KameleoonClient ---
const client = createClient({
  siteCode: 'my_site_code',
  externals: {
    visitorCodeManager: new MyVisitorCodeManager(),
  },
});

Requester​

import {
  RequestType,
  IExternalRequester,
  KameleoonResponseType,
  SendRequestParametersType,
} from '@kameleoon/react-sdk';

// --- External Requester Implementation
export class MyRequester implements IExternalRequester {
  public async sendRequest({
    url,
    parameters,
  }: SendRequestParametersType<RequestType>): Promise<KameleoonResponseType> {
    // - Using native browser `fetch`
    return await fetch(url, parameters);
  }
}

// --- Create KameleoonClient ---
const client = createClient({
  siteCode: 'my_site_code',
  externals: {
    requester: new MyRequester(),
  },
});

Pseudo Random Number Generator​

Pseudo Random Number Generator (PRNG) is a dependency that generates random floating point number between 0 and 1 (similar to Math.random).

Default Kameleoon implementation relies on Browser's crypto or Math.random function if crypto is not available. Those API are very secure and reliable, however in some edge cases (especially in some React Native engines) you might want to provide your own implementation or use a dedicated Kameleoon package for React Native - @kameleoon/react-native-secure-prng

import { IExternalPRNG } from '@kameleoon/react-sdk';

// --- External Pseudo Random Number Generator (PRNG) implementation ---
class MyPRNG implements IExternalPRNG {
  public getRandomNumber(): number {
    // Return a random floating point number between `0` and `1` like `Math.random()` does
    return Math.random();
  }
}

// --- Create KameleoonClient ---
const client = createClient({
  siteCode: 'my_site_code',
  externals: {
    prng: new MyPRNG(),
  },
});

Logger​

import { KameleoonClient, KameleoonLogger, IExternalLogger, LogLevel } from '@kameleoon/react-sdk';

// --- Custom Logger Implementation
export class CustomLogger implements IExternalLogger {
  public log(level: LogLevel, message: string): void {
    // Custom log handling logic here.
  }
}

// --- Create KameleoonClient ---
const client = createClient({
  siteCode: 'my_site_code',
  externals: {
    logger: new CustomLogger(),
  },
});

Error Handling​

Almost every React SDK callback which is returned by hooks may throw an error at some point, these errors are not just caveats but rather deliberately predefined KameleoonErrors that extend native JavaScript Error class providing useful messages and special type field with a type KameleoonException.

KameleoonException is an enum containing all possible error variants.

To know exactly what variant of KameleoonException the callbacks may throw, you can check Throws section of the hooks description on this page or just hover over the callback in your IDE to see jsdocs description.

Overall handling the errors considered a good practice to make your application more stable and avoid technical issues.

import { useEffect, useCallback } from 'react';
import {
  useInitialize,
  useVisitorCode,
  useData,
  CustomData,
  KameleoonError,
  KameleoonException,
} from '@kameleoon/react-sdk';

function MyComponent(): JSX.Element {
  const { initialize } = useInitialize();
  const { getVisitorCode } = useVisitorCode();
  const { addData } = useData();

  const init = useCallback(async (): Promise<void> => {
    try {
      await initialize();

      // -- Get visitor code
      const visitorCode = getVisitorCode();

      const customData = new CustomData(0, 'my_data');
      addData(visitorCode, customData);
    } catch (error) {
      // -- Type guard for inferring error type as native JavaScript `catch`
      //    only infers `unknown`
      if (error instanceof KameleoonError) {
        switch (error.type) {
          case KameleoonException.VisitorCodeMaxLength:
            // -- Handle an error
            break;
          case KameleoonException.StorageWrite:
            // -- Handle an error
            break;
          case KameleoonException.Initialization:
            // -- Handle an error
            break;
          default:
            break;
        }
      }
    }
  }, [initialize, addData, visitorCode, getVisitorCode]);

  useEffect(() => {
    init();
  }, [init]);
}

Cross-device experimentation​

To support visitors who access your app from multiple devices cross-device experimentation, Kameleoon allows you to synchronize your custom data across each of the visitor's devices and reconcile their visit history across each device.

Synchronizing custom data across devices​

If you want to synchronize your Custom Data across multiple devices, Kameleoon provides a custom data synchronization mechanism.

To use this feature, in the custom data dashboard, edit the custom data and set the Scope value to Visitor. The custom data will now be permanently associated with a specific visitor as long as getRemoteVisitorData is called before any other actions with the visitor-associated data.

After the custom data is set up, calling getRemoteVisitorData makes the latest data accessible on any device.

See the following example of data synchronization between two devices:

Device One
import { useEffect, useCallback } from 'react';
import { useInitialize, useData, CustomData } from '@kameleoon/react-sdk';

function MyComponent(): JSX.Element {
  const { initialize } = useInitialize();
  const { addData, flush } = useData();

  const init = useCallback(async (): Promise<void> => {
    await initialize();

    // -- Custom Data with index `0` was set to `Visitor` scope
    //    on Kameleoon Platform
    const customDataIndex = 0;
    const customData = new CustomData(customDataIndex, 'my_data');

    addData('my_visitor', customData);
    flush();
  }, [initialize, addData]);

  useEffect(() => {
    init();
  }, [init]);
}
Device Two
import { useEffect, useCallback } from 'react';
import { useInitialize, useData, CustomData } from '@kameleoon/react-sdk';

function MyComponent(): JSX.Element {
  const { initialize } = useInitialize();
  const { getRemoteVisitorData } = useData();

  const init = useCallback(async (): Promise<void> => {
    await initialize();

    // -- Before working with data, make `getRemoteVisitorData` call
    await getRemoteVisitorData({ visitorCode: 'my_visitor_code' });

    // -- The further SDK code will have an access to CustomData with `Visitor` scope
    //    defined on Device One.
    //    So "my_data" is now available for targeting and tracking for "my_visitor"
  }, [initialize, addData]);

  useEffect(() => {
    init();
  }, [init]);
}

Using custom data for session merging​

Cross-device experimentation allows you to combine a visitor's history across each of their devices (history reconciliation). One of the powerful features that history reconciliation provides is the ability to merge different visitors sessions into one. To reconcile visit history, you can use CustomData to provide a unique identifier for the visitor.

Follow the activating cross-device history reconciliation guide to set up your custom data on the Kameleoon platform

When your custom data is set up, you can use it in your code to merge a visitor's session. Sessions with the same identifier will always see the same experiment variation and will be displayed as a single visitor in the Visitor view of your experiment's result pages.

The SDK configuration ensures that associated sessions always see the same variation of the experiment.

Before using other methods make sure to let SDK know that the visitor is a unique identifier by adding UniqueIdentifier data to a visitor

tip

As the custom data you use as the identifier must be set to Visitor scope, you need to use cross-device custom data synchronization to retrieve the identifier with the getRemoteVisitorData method on each device.

Here's an example of how to use custom data for session merging. In this example, we have an application with a login page. Since we don't know the user ID at the moment of login, we use an anonymous visitor identifier generated by the getVisitorCode method. After the user logs in, we can associate the anonymous visitor with the user ID and use it as a unique identifier for the visitor.

Login Page
import { useEffect, useCallback } from 'react';
import {
  useInitialize,
  useFeatureFlag,
  useVisitorCode,
  CustomData,
} from '@kameleoon/react-sdk';

function LoginPage(): JSX.Element {
  const [visitorCode, setVisitorCode] = useState<string | null>(null);

  const { initialize } = useInitialize();
  const { getFeatureFlagVariationKey } = useFeatureFlag();
  const { getVisitorCode } = useVisitorCode();

  const init = useCallback(async (): Promise<void> => {
    await initialize();

    const anonymousVisitor = getVisitorCode();
    // -- Saving `visitorCode` in the state to later re-use it
    setVisitorCode(anonymousVisitor);

    // -- Getting some variation, assume it's variation `A`
    const variation = getFeatureFlagVariationKey(
      anonymousVisitor,
      'my_feature_key',
    );
  }, [initialize, getFeatureFlagVariationKey, getVisitorCode]);

  useEffect(() => {
    init();
  }, [init]);
}
Application Page
import { useEffect, useCallback } from 'react';
import {
  useData,
  useFeatureFlag,
  useVisitorCode,
  CustomData,
  UniqueIdentifier,
} from '@kameleoon/react-sdk';

type Props = {
  anonymousVisitor: string;
};

function ApplicationPage(props: Props): JSX.Element {
  const { addData, trackConversion, getRemoteVisitorData } = useData();
  const { getFeatureFlagVariationKey } = useFeatureFlag();

  const init = useCallback(async (): Promise<void> => {
    // -- At this point anonymous visitor has logged in
    //    and we have user ID to use as a visitor identifier
    // -- Associating both visitors with identifier Custom Data,
    //    where index `1` is the index of the Custom Data configured
    //    as a unique identifier on Kameleoon Platform
    const userIdentifierData = new CustomData(1, 'my_user_id');
    // -- Let's assume that anonymous visitor identifier
    //    was passed as a prop
    addData(props.anonymousVisitor, userIdentifierData);

    // -- Letting SDK know that the visitor is unique identifier
    addData('my_user_id', new UniqueIdentifier(true));

    // -- Getting the variation for user ID will
    //    result in the same variation as for anonymous visitor
    //    variation will be `A`
    const variation = getFeatureFlagVariationKey(
      'my_user_id',
      'my_feature_key',
    );

    // -- `my_user_id` and `anonymousVisitor` are now linked
    //    They can be tracked as a single visitor
    trackConversion({
      visitorCode: 'my_user_id',
      goalId: 123,
      revenue: 100,
    });

    // -- Moreover linked visitors share previously
    //    collected remote data
    const data = await getRemoteVisitorData({
      visitorCode: 'my_user_id',
    });
  }, [
    getRemoteVisitorData,
    trackConversion,
    addData,
    getFeatureFlagVariationKey,
  ]);

  useEffect(() => {
    init();
  }, [init]);
}

Utilities​

SDK has a set of utility methods that can be used to simplify the development process. All the methods are represented as static members of KameleoonUtils class.

simulateSuccessRequest​

Method simulateSuccessRequest is used to simulate a successful request to the Kameleoon server. It can be useful for custom Requester implementations when developer needs to simulate a successful request, for example disabling tracking.

import {
  KameleoonUtils,
  IExternalRequester,
  SendRequestParametersType,
  RequestType,
  KameleoonResponseType,
} from '@kameleoon/react-sdk';

// - Example of `Requester` with disabled tracking
class Requester implements IExternalRequester {
  public async sendRequest({
    url,
    parameters,
    requestType,
  }: SendRequestParametersType<RequestType>): Promise<KameleoonResponseType> {
    if (requestType === RequestType.Tracking) {
      return KameleoonUtils.simulateSuccessRequest<RequestType.Tracking>(
        requestType,
        null,
      );
    }

    return await fetch(url, parameters);
  }
}
Parameters​
NameTypeDescription
requestType (required)RequestTypeA type of request
data (required)SimulateRequestDataType[RequestType]A type of request data, which is different depending on RequestType

Data type SimulateRequestDataType is defined as follows:

  • RequestType.Tracking - null
  • RequestType.ClientConfiguration - ClientConfigurationDataType
  • RequestType.RemoteData - JSONType
Returns​

Promise<KameleoonResponseType> - returns a promise with the response of the request

getCookieValue​

Method getCookieValue is used to parse a common cookie string (key_1=value_1; key_2=value_2; ...) and get the value of a specific cookie key. It's useful when working with a custom implementation of VisitorCodeManager.

import { KameleoonUtils } from '@kameleoon/react-sdk';

const cookies = 'key_1=value_1; key_2=value_2';
const key = 'key_1';

const value = KameleoonUtils.getCookieValue(cookies, key); // = `value_1`
Parameters​
NameTypeDescription
cookie (required)stringCookie string in a form key_1=value_1; key_2=value_2
key (required)stringString representation of a key to find a value by
Returns​

string | null - returns a string with a cookie value or null if the key was not found

Reference​

This is the full reference documentation for the React SDK.

Initialization​

This section provides the methods you use to create and initialize the Kameleoon Client in your application.

initialize()​

An asynchronous initialize function, collected with useInitialize hook, that's used for KameleoonClient initialization by fetching Kameleoon SDK related data from server or by retrieving data from local source if data is up-to-date or update interval has not been reached.

note

If the SDK configuration could not be retrieved but there is an older configuration available in SDK storage, the SDK uses the older configuration as a fallback and the initialize does not throw an error.

note

SDK supports an offline mode.

In offline mode if tracking requests from any of the following methods fail due to internet connectivity issues, the SDK automatically resends the request as soon as it detects that the internet connection has been re-established:

import { useEffect, useCallback } from 'react';
import { useInitialize } from '@kameleoon/react-sdk';

function MyComponent(): JSX.Element {
  const { initialize } = useInitialize();

  const init = useCallback(async (): Promise<void> => {
    await initialize();
  }, [initialize]);

  useEffect(() => {
    init();
  }, [init]);
}
Returns​

Promise<boolean> - a promise resolved to a boolean indicating a successful sdk initialization. Generally initialize will throw an error if the something that can not be handled will happen, so the boolean value will almost always be true and won't give as much useful information.

Throws​
TypeDescription
KameleoonException.StorageWriteCouldn't update storage data
KameleoonException.ClientConfigurationCouldn't retrieve client configuration from Kameleoon API
KameleoonException.MaximumRetriesReachedMaximum retries reached, request failed

isInitialized()​

The isInitialized function, collected with the useInitialize hook, is a small utility method that checks if the SDK initialization has completed. For example, this can be useful when dealing with a deeply nested component tree, because it allows you to quickly check the SDK readiness without having to manage a global state, or pass the initialization result using component props.

import { useEffect, useCallback } from 'react';
import { useInitialize, useFeatureFlag } from '@kameleoon/react-sdk';

function MyComponent(): JSX.Element {
  const { initialize } = useInitialize();

  const init = useCallback(async (): Promise<void> => {
    await initialize();
  }, [initialize]);

  useEffect(() => {
    init();
  }, [init]);
}

function DeeplyNestedComponent(): JSX.Element {
  const { isInitialized } = useInitialize();
  const { getFeatureFlagVariationKey } = useFeatureFlag();

  if (isInitialized()) {
    const variation = getFeatureFlagVariationKey('my_feature_key');
  }
}
Returns​

A boolean value. Returns true if SDK was successfully initialized, otherwise returns false.

createClient()​

To get started, you need to create an entry point for React SDK by creating a Kameleoon Client at the top level of your application using the createClient() function imported from kameleoon package.

An instance of KameleoonClient is created using createClient() function.

import {
  createClient,
  Environment,
  SDKConfigurationType,
} from '@kameleoon/react-sdk';

// -- Optional configuration
const configuration: Partial<SDKConfigurationType> = {
  updateInterval: 60,
  environment: Environment.Production,
  domain: '.example.com',
};

const client = createClient({ siteCode: 'my_site_code', configuration });
Parameters​

An object of type SDKParameters containing:

NameTypeDescription
siteCode (required)stringThis is a unique key of the Kameleoon project you are using with the SDK. This field is mandatory.
configuration (optional)Partial<SDKConfigurationType>client's configuration
externals (optional)ExternalsTypeexternal implementation of SDK dependencies (External dependencies)
Configuration Parameters​
NameTypeDescriptionDefault Value
updateInterval (optional)numberupdate interval in minutes for sdk configuration; minimum value is 1 minute60
environment (optional)Environmentfeature flag environmentEnvironment.Production
targetingDataCleanupInterval (optional)numberinterval in minutes for cleaning up targeting data; minimum value is 1 minuteundefined (no cleanup will be performed)
cookieDomain (optional)stringdomain that the cookie belongs to.undefined
networkDomain (optional)stringcustom domain the SDKs uses for all outgoing network requests, commonly used for proxying. The format is second_level_domain.top_level_domain (for example, example.com). If an invalid format is specified, the SDK uses the default Kameleoon valueundefined
requestTimeout (optional)numbertimeout in milliseconds for all SDK network requests, if timeout is exceeded request will fail immediately10_000 (10 seconds)
trackingInterval (optional)numberSpecifies the interval for tracking requests, in milliseconds. All visitors who were evaluated for any feature flag or had associated data will be included in this tracking request, which is performed once per interval. The minimum value is 100 ms and the maximum value is 1_000 ms1_000 (1 second)
Returns​

KameleoonClient - an instance of KameleoonClient.

note

Make sure not to use several client instances in one application as it is not fully supported yet and may overwrite the local storage configuration and cause unintended behavior (bugs).

Feature flags and variations​

This section provides the methods you use to retrieve and manage the feature flags and variations assigned to the visitor.

getVariation()​

  • 📨 Sends Tracking Data to Kameleoon (depending on the track parameter)
  • 🎯 Events: EventType.Evaluation
info

Method is obtained using useFeatureFlag hook.

Retrieves the VariationType assigned to a given visitor for a specific feature flag.

This method takes a visitorCode and featureKey as mandatory arguments. The track argument is optional and defaults to true.

It returns the assigned VariationType for the visitor. If the visitor is not associated with any feature flag rules, the method returns the default VariationType for the given feature flag.

Ensure that proper error handling is implemented in your code to manage potential exceptions.

note

The default variation refers to the variation assigned to a visitor when they do not match any predefined delivery rules for a feature flag. In other words, it is the fallback variation applied to all users who are not targeted by specific rules. It's represented as the variation in the "Then, for everyone else..." section in a management interface.

import { useEffect, useCallback } from 'react';
import {
  useInitialize,
  useFeatureFlag,
  useVisitorCode,
} from '@kameleoon/react-sdk';

function MyComponent(): JSX.Element {
  const { initialize } = useInitialize();
  const { getVariation } = useFeatureFlag();
  const { getVisitorCode } = useVisitorCode();

  const init = useCallback(async (): Promise<void> => {
    await initialize();

    // -- Get visitor code using `getVisitorCode` function
    const visitorCode = getVisitorCode();

    // -- Get variation with tracking
    const variation = getVariation({
      visitorCode,
      featureKey: 'my_feature_key',
    });

    // -- Get variation without tracking
    const variation = getVariation({
      visitorCode,
      featureKey: 'my_feature_key',
      track: false,
    });

    // -- An Example variation:
    // {
    //  key: 'variation_key',
    //  id: 123,
    //  experimentId: 456,
    //  variables: Map {
    //    'variable_key' => {
    //      key: 'variable_key',
    //      type: VariableType.BOOLEAN,
    //      value: true,
    //    }
    //  },
    // }
  }, [initialize, visitorCode, getVariation, getVisitorCode]);

  useEffect(() => {
    init();
  }, [init]);
}
Parameters​

An object of type GetVariationParamsType with the following properties:

NameTypeDescriptionDefault
visitorCode (required)stringUnique identifier of the user.
featureKey (required)stringKey of the feature you want to expose to a user.
track (optional)booleanAn optional parameter to enable or disable tracking of the feature evaluation.true
Return value​
TypeDescription
VariationTypeAn assigned variation to a given visitor for a specific feature flag.
Exceptions thrown​
TypeDescription
KameleoonException.InitializationMethod was executed before the kameleoonClient completed it's initialize call.
KameleoonException.VisitorCodeEmptyThe visitor code is empty.
KameleoonException.VisitorCodeMaxLengthThe visitor code exceeded the maximum length (255 characters).
KameleoonException.FeatureFlagConfigurationNotFoundException indicating that the requested feature key wasn't found in the internal configuration of the SDK. This usually means that the feature flag is not activated in the Kameleoon app (but code implementing the feature is already deployed on your application).
KameleoonException.FeatureFlagEnvironmentDisabledException indicating that feature flag is disabled for the visitor's current environment (for example, production, staging, or development).
|

getVariations()​

  • 📨 Sends Tracking Data to Kameleoon (depending on the track parameter)
  • 🎯 Events: EventType.Evaluation
info

Method is obtained using useFeatureFlag hook.

Retrieves a map of VariationType objects assigned to a given visitor across all feature flags.

This method iterates over all available feature flags and returns the assigned VariationType for each flag associated with the specified visitor. It takes visitorCode as a mandatory argument, while onlyActive and track are optional.

  • If onlyActive is set to true, the method getVariations() will return feature flags variations provided the user is not bucketed with the off variation.
  • The track parameter controls whether or not the method will track the variation assignments. By default, it is set to true. If set to false, the tracking will be disabled.

The returned map consists of feature flag keys as keys and their corresponding VariationType as values. If no variation is assigned for a feature flag, the method returns the default VariationType for that flag.

Proper error handling should be implemented to manage potential exceptions.

note

The default variation refers to the variation assigned to a visitor when they do not match any predefined delivery rules for a feature flag. In other words, it is the fallback variation applied to all users who are not targeted by specific rules. It's represented as the variation in the "Then, for everyone else..." section in a management interface.

import { useEffect, useCallback } from 'react';
import {
  useInitialize,
  useFeatureFlag,
  useVisitorCode,
} from '@kameleoon/react-sdk';

function MyComponent(): JSX.Element {
  const { initialize } = useInitialize();
  const { getVariations } = useFeatureFlag();
  const { getVisitorCode } = useVisitorCode();

  const init = useCallback(async (): Promise<void> => {
    await initialize();

    // -- Get visitor code using `getVisitorCode` function
    const visitorCode = getVisitorCode();

    // -- Get all feature flag variations with tracking
    const variations = getVariations({
      visitorCode,
    });

    // -- Get active feature flag variations with tracking
    const variations = getVariations({
      visitorCode,
      onlyActive: true,
    });

    // -- Get active feature flag variations without tracking
    const variations = getVariations({
      visitorCode,
      onlyActive: true,
      track: false,
    });

    // -- An Example variations:
    // Map {
    // 'feature_key' => {
    //    key: 'variation_key',
    //    id: 123,
    //    experimentId: 456,
    //    variables: Map {
    //      'variable_key' => {
    //        key: 'variable_key',
    //        type: VariableType.BOOLEAN,
    //        value: true,
    //      }
    //    },
    //   }
    // }
  }, [initialize, visitorCode, getVariations, getVisitorCode]);

  useEffect(() => {
    init();
  }, [init]);
}
Parameters​

An object of type GetVariationsParamsType with the following properties:

NameTypeDescriptionDefault
visitorCode (required)stringUnique identifier of the user.
onlyActive (optional)booleanAn optional parameter indicating whether to return variations for active (true) or all (false) feature flags.false
track (optional)booleanAn optional parameter to enable or disable tracking of the feature evaluation.true
Return value​
TypeDescription
Map<string, VariationType>Map that contains the assigned VariationType objects of the feature flags using the keys of the corresponding features.
Exceptions thrown​
TypeDescription
KameleoonException.InitializationMethod was executed before the kameleoonClient completed it's initialize call.
KameleoonException.VisitorCodeEmptyThe visitor code is empty.
KameleoonException.VisitorCodeMaxLengthThe visitor code exceeded the maximum length (255 characters).

isFeatureFlagActive()​

  • 📨 Sends Tracking Data to Kameleoon (depending on the track parameter)
  • 🎯 Events: EventType.Evaluation

The method isFeatureFlagActive(), used with the useFeatureFlag hook, determines whether a visitor identified by visitorCode has the specified featureKey active. This method checks the targeting conditions, identifies the variation for the visitor, and saves this information to storage. Additionally, the hook sends a tracking request.

There is also an overload for this method that includes a track parameter, allowing you to disable the tracking of the feature evaluation.

note

Visitor must be targeted to has feature flag active

import { useEffect, useCallback } from 'react';
import {
  useInitialize,
  useData,
  useFeatureFlag,
  useVisitorCode,
  CustomData,
} from '@kameleoon/react-sdk';

function MyComponent(): JSX.Element {
  const { initialize } = useInitialize();
  const { addData } = useData();
  const { isFeatureFlagActive } = useFeatureFlag();
  const { getVisitorCode } = useVisitorCode();

  const init = useCallback(async (): Promise<void> => {
    await initialize();

    // -- Get visitor code using `getVisitorCode` function
    const visitorCode = getVisitorCode();

    const featureKey = 'my_feature_key';

    // -- Add CustomData with index `0` containing visitor id to check the targeting
    addData(visitorCode, new CustomData(0, 'visitor_id'));

    // -- Get the status of feature flag
    const isActive = isFeatureFlagActive(visitorCode, featureKey);

    // -- Check if the feature flag is active for visitor without tracking
    const isActive = isFeatureFlagActive({ visitorCode, featureKey: 'my_feature, track: false});
  }, [initialize, visitorCode, isFeatureFlagActive, getVisitorCode]);

  useEffect(() => {
    init();
  }, [init]);
}
Parameters​

There are two overloads available for this method:

  1. Two parameters overload:
danger

This overload is deprecated and will be removed in the next major version. Please use the new overload with an object parameter.

NameTypeDescription
visitorCode (required)stringunique visitor identification string, can't exceed 255 characters length
featureKey (required)stringa unique key for feature flag
  1. Object parameter overload of type IsFeatureFlagActiveParamsType:
NameTypeDescriptionDefault
visitorCode (required)stringunique visitor identification string, can't exceed 255 characters length-
featureKey (required)stringa unique key for feature flag-
track (optional)booleana boolean indicator of whether to track the feature evaluationtrue
Returns​

boolean - indicator of whether the feature flag with featureKey is active for visitor with visitorCode.

Throws​
TypeDescription
KameleoonException.InitializationMethod was executed before the kameleoonClient completed it's initialize call
KameleoonException.VisitorCodeMaxLengthThe visitor code exceeded the maximum length (255 characters)
KameleoonException.VisitorCodeEmptyThe visitor code is empty
KameleoonException.NotTargetedCurrent visitor is not targeted
KameleoonException.FeatureFlagConfigurationNotFoundNo feature flag was found for the specified featureKey
KameleoonException.DataInconsistencyAllocated variation was found but there is no feature flag with according featureKey

getFeatureFlagVariationKey()​

  • 📨 Sends Tracking Data to Kameleoon
  • 🎯 Events: EventType.Evaluation
caution

This method is deprecated and will be removed in the next major version. Please use the new method getVariation

The method getFeatureFlagVariationKey(), which is used with the useFeatureFlag hook, retrieves the variation key for a visitor identified by their visitorCode. This process includes checking the targeting criteria, identifying the appropriate variation assigned to the visitor, storing this information, and sending a tracking request.

note

If a user has never been associated with a feature flag, the SDK will randomly return a variation key according to the rules of that feature flag. If the user is already linked to the feature flag, the SDK will identify the previously assigned variation key. If the user does not meet any of the specified rules, the SDK will return the default value defined in Kameleoon’s feature flag delivery rules. It’s important to note that the default value may not always be a variation key; it could also be a boolean value or another data type, depending on how the feature flag is configured.

import { useEffect, useCallback } from 'react';
import {
  useInitialize,
  useFeatureFlag,
  useVisitorCode,
} from '@kameleoon/react-sdk';

function MyComponent(): JSX.Element {
  const { initialize } = useInitialize();
  const { getFeatureFlagVariationKey } = useFeatureFlag();
  const { getVisitorCode } = useVisitorCode();

  const init = useCallback(async (): Promise<void> => {
    await initialize();

    // -- Get visitor code using `getVisitorCode` function
    const visitorCode = getVisitorCode();

    const featureKey = 'my_feature_key';

    // -- Get the variationKey for the visitor under `visitorCode` in the found feature flag
    const variationKey = getFeatureFlagVariationKey(visitorCode, featureKey);
  }, [initialize, visitorCode, getFeatureFlagVariationKey, getVisitorCode]);

  useEffect(() => {
    init();
  }, [init]);
}
Parameters​
NameTypeDescription
visitorCode (required)stringunique visitor identification string, can't exceed 255 characters length
featureKey (required)stringa unique key for feature flag
Returns​

string - a string containing variable key for the allocated feature flag variation for the provided visitor.

Throws​
TypeDescription
KameleoonException.InitializationMethod was executed before initialize was done for kameleoonClient
KameleoonException.VisitorCodeMaxLengthThe visitor code exceeded the maximum length (255 characters)
KameleoonException.VisitorCodeEmptyThe visitor code is empty
KameleoonException.NotTargetedCurrent visitor is not targeted
KameleoonException.FeatureFlagConfigurationNotFoundNo feature flag was found for the specified featureKey
KameleoonException.FeatureFlagEnvironmentDisabledFeature flag is disabled for the current environment

getFeatureFlags()​

🚫 Doesn't send Tracking Data to Kameleoon

caution

This method is deprecated and will be removed in the next major version. Please use the new method getVariations

Method getFeatureFlags collected with useFeatureFlag hook returns a list of feature flags stored in the client configuration.

import { useEffect, useCallback } from 'react';
import { useInitialize, useFeatureFlag } from '@kameleoon/react-sdk';

function MyComponent(): JSX.Element {
  const { initialize } = useInitialize();
  const { getFeatureFlags } = useFeatureFlag();

  const init = useCallback(async (): Promise<void> => {
    await initialize();

    // -- Get list of all feature flags
    const featureFlags = getFeatureFlags();
  }, [initialize, getFeatureFlags]);

  useEffect(() => {
    init();
  }, [init]);
}
Returns​

FeatureFlagType[] - list of feature flags, each feature flag item contains id and key.

Throws​
TypeDescription
KameleoonException.InitializationMethod was executed before the kameleoonClient completed it's initialize call

getVisitorFeatureFlags()​

  • 🚫 Doesn't send Tracking Data to Kameleoon
  • 🎯 Events: EventType.Evaluation (for each feature flag)
caution

This method is deprecated and will be removed in the next major version. Please use the new method getVariations

The getVisitorFeatureFlags method, utilized with the useFeatureFlag hook, returns a list of active feature flags that target the visitor associated with the visitorCode (the visitor must have one of the allocated variations).

caution

This method only collects the feature flags that are currently active for the visitor. As a result, it does not include any feature flags for which the visitor is assigned to the “off” variation (default or control). If you need to retrieve all of the visitor’s feature flags, use getFeatureFlags instead.

For example:

// -- `getVisitorFeatureFlags` doesn't trigger feature experiment
//    it only returns feature flags, where visitor didn't get `off` variation
getVisitorFeatureFlags('my_visitor').forEach(({ key }) => {
  // -- `getFeatureFlagVariationKey` triggers feature experiment,
  //    as `off` is already filtered out - I will never see
  //    visitor taking part in experiment, where `off` variation was allocated
  getFeatureFlagVariationKey('my_visitor', key);
});

For cases where you need all of the visitor's feature flags, use getFeatureFlags instead:

// -- Both `off` and other variations are processed as expected
getFeatureFlags('my_visitor').forEach(({ key }) => {
  getFeatureFlagVariationKey('my_visitor', key);
});
import { useEffect, useCallback } from 'react';
import {
  useInitialize,
  useFeatureFlag,
  useVisitorCode,
} from '@kameleoon/react-sdk';

function MyComponent(): JSX.Element {
  const { initialize } = useInitialize();
  const { getVisitorCode } = useVisitorCode();
  const { getVisitorFeatureFlags } = useFeatureFlag();

  const init = useCallback(async (): Promise<void> => {
    await initialize();

    // -- Get visitor code
    const visitorCode = getVisitorCode();

    // -- Get active feature flags for visitor
    const featureFlags = getVisitorFeatureFlags(visitorCode);
  }, [initialize, visitorCode, getVisitorFeatureFlags, getVisitorCode]);

  useEffect(() => {
    init();
  }, [init]);
}
Parameters​
NameTypeDescription
visitorCode (required)stringunique visitor identification string, can't exceed 255 characters length
Returns​

FeatureFlagType[] - list of feature flags, each feature flag item contains id and key.

Throws​
TypeDescription
KameleoonException.InitializationMethod was executed before the kameleoonClient completed it's initialize call
KameleoonException.VisitorCodeMaxLengthThe visitor code exceeded the maximum length (255 characters)
KameleoonException.VisitorCodeEmptyThe visitor code is empty
KameleoonException.NotTargetedCurrent visitor is not targeted
KameleoonException.StorageReadError while reading storage data

getActiveFeatureFlags()​

  • 🚫 Doesn't send Tracking Data to Kameleoon
  • 🎯 Events: EventType.Evaluation (for each feature flag)
caution

This method is deprecated and will be removed in the next major version. Please use the new method getVariations

Method getActiveFeatureFlags, collected with the useFeatureFlag hook, returns a Map, where key is feature key and value is detailed information about the visitor's variation and it's variables

import { useEffect, useCallback } from 'react';
import {
  useInitialize,
  useFeatureFlag,
  useVisitorCode,
} from '@kameleoon/react-sdk';

function MyComponent(): JSX.Element {
  const { initialize } = useInitialize();
  const { getVisitorCode } = useVisitorCode();
  const { getActiveFeatureFlags } = useFeatureFlag();

  const init = useCallback(async (): Promise<void> => {
    await initialize();

    // -- Get visitor code
    const visitorCode = getVisitorCode();

    // -- Get active feature flags for visitor
    //    with detailed variation and variables data
    const activeFeatures = getActiveFeatureFlags(visitorCode);

    // -- Result example:
    // Map {
    //   'feature-key-one' => {
    //     id: 100,
    //     key: 'variation-key-one',
    //     experimentId: 200,
    //     variables: [
    //      { key: 'variable_bool', type: VariableType.Boolean, value: true },
    //     ]
    //   },
    //   'feature-key-two' => {
    //     id: null, // -> `null` because it is default variation
    //     key: 'default-variation-key',
    //     experimentId: null, // -> `null` because it is default variation
    //     variables: []
    //   }
    // }
  }, [initialize, visitorCode, getVisitorFeatureFlags, getVisitorCode]);

  useEffect(() => {
    init();
  }, [init]);
}

init();
caution

This method only collects the visitor's active feature flags. This means the result excludes all the feature flags for which the visitor is assigned to the off (default or control) variation. When you need all of the visitor's feature flags to iterate over, use getFeatureFlags instead.

See the getVisitorFeatureFlags CAUTION section method for more details.

Parameters​
NameTypeDescription
visitorCode (required)stringunique visitor identification string, can't exceed 255 characters length
Returns​

Map<string, KameleoonVariationType> - a map of feature flags, where key is feature key and value is detailed information about the visitor's variation and it's variables

Throws​
TypeDescription
KameleoonException.InitializationMethod was executed before the kameleoonClient completed it's initialize call
KameleoonException.VisitorCodeMaxLengthThe visitor code exceeded the maximum length of 255 characters
KameleoonException.VisitorCodeEmptyThe visitor code is empty
KameleoonException.StorageReadError while reading storage data
KameleoonException.NumberParseCouldn't parse Number value
KameleoonException.JSONParseCouldn't parse JSON value

Variables​

This section provides the methods you use to retrieve and manage the variables assigned to the visitor.

getFeatureFlagVariable()​

  • 📨 Sends Tracking Data to Kameleoon
  • 🎯 Events: EventType.Evaluation
caution

This method is deprecated and will be removed in the next major version. Please use the new method getVariation

Method getFeatureFlagVariable collected with useFeatureFlag hook returns a variable for the visitor under visitorCode in the found feature flag, this includes targeting check, finding the according variation exposed to the visitor and saving it to storage along with sending tracking request.

import { useEffect, useCallback } from 'react';
import {
  useInitialize,
  useVisitorCode,
  useFeatureFlag,
  VariableType,
  JSONType,
} from '@kameleoon/react-sdk';

function MyComponent(): JSX.Element {
  const { initialize } = useInitialize();
  const { getVisitorCode } = useVisitorCode();
  const { getFeatureFlagVariable } = useFeatureFlag();

  const init = useCallback(async (): Promise<void> => {
    await initialize();

    // -- Get visitor code
    const visitorCode = getVisitorCode();

    // -- Get feature variable
    const result = getFeatureFlagVariable({
      visitorCode,
      featureKey: 'my_feature_key',
      variableKey: 'my_variable_key',
    });

    // -- Infer the type of variable by it's `type`
    switch (result.type) {
      case VariableType.BOOLEAN:
        const myBool: boolean = result.value;
        break;
      case VariableType.NUMBER:
        const myNum: number = result.value;
        break;
      case VariableType.JSON:
        const myJson: JSONType = result.value;
        break;
      case VariableType.STRING:
      case VariableType.JS:
      case VariableType.CSS:
        const myStr: string = result.value;
        break;
      default:
        break;
    }
  }, [initialize, getFeatureFlagVariable, visitorCode, getVisitorCode]);

  useEffect(() => {
    init();
  }, [init]);
}
Parameters​

Parameters object of type GetFeatureFlagVariableParamsType containing the following fields:

NameTypeDescription
visitorCode (required)stringunique visitor identification string, can't exceed 255 characters length
featureKey (required)stringa unique key for feature flag
variableKey (required)stringkey of the variable to be found for a feature flag with the specified featureKey, can be found on Kameleoon Platform
Returns​

FeatureFlagVariableType - a variable object containing type and value fields. You can check the type field against VariableType enum. For example, if the type is VariableType.BOOLEAN then value will be a boolean type.

Throws​
TypeDescription
KameleoonException.InitializationMethod was executed before initialize was done for kameleoonClient
KameleoonException.VisitorCodeMaxLengthThe visitor code exceeded the maximum length (255 characters)
KameleoonException.VisitorCodeEmptyThe visitor code is empty
KameleoonException.NotTargetedCurrent visitor is not targeted
KameleoonException.FeatureFlagConfigurationNotFoundNo feature flag was found for the specified featureKey
KameleoonException.FeatureFlagVariableNotFoundNo feature variable was found for the specified visitorCode and variableKey
KameleoonException.FeatureFlagEnvironmentDisabledFeature flag is disabled for the current environment
KameleoonException.JSONParseCouldn't parse JSON value
KameleoonException.NumberParseCouldn't parse Number value

getFeatureFlagVariables()​

  • 📨 Sends Tracking Data to Kameleoon
  • 🎯 Events: EventType.Evaluation (for each feature flag)
caution

This method is deprecated and will be removed in the next major version. Please use the new method getVariations

Method getFeatureFlagVariables collected with useFeatureFlag hook returns a list of variables for the visitor under visitorCode in the found feature flag, this includes targeting check, finding the according variation exposed to the visitor and saving it to storage along with sending tracking request.

import { useEffect, useCallback } from 'react';
import {
  useInitialize,
  useFeatureFlag,
  useVisitorCode,
} from '@kameleoon/react-sdk';

function MyComponent(): JSX.Element {
  const { initialize } = useInitialize();
  const { getVisitorCode } = useVisitorCode();
  const { getFeatureFlagVariables } = useFeatureFlag();

  const init = useCallback(async (): Promise<void> => {
    await initialize();

    // -- Get visitor code
    const visitorCode = getVisitorCode();

    // -- Get a list of variables for the visitor under `visitorCode` in the found feature flag
    const variables = getFeatureFlagVariables(visitorCode, 'my_feature_key');
  }, [initialize, getFeatureFlagVariables, getVisitorCode]);

  useEffect(() => {
    init();
  }, [init]);
}
Parameters​
NameTypeDescription
visitorCode (required)stringunique visitor identification string, can't exceed 255 characters length
featureKey (required)stringa unique key for feature flag
Returns​

FeatureVariableResultType[] - a list of variable objects containing key, type and value fields. You can check the type field against VariableType enum. For example, if the type is VariableType.BOOLEAN then value will be a boolean type.

Throws​
TypeDescription
KameleoonException.InitializationMethod was executed before the kameleoonClient completed it's initialize call
KameleoonException.VisitorCodeMaxLengthThe visitor code exceeded the maximum length (255 characters)
KameleoonException.VisitorCodeEmptyThe visitor code is empty
KameleoonException.NotTargetedCurrent visitor is not targeted
KameleoonException.FeatureFlagConfigurationNotFoundNo feature flag was found for the specified featureKey
KameleoonException.FeatureFlagVariationNotFoundNo feature variation was found for the specified visitorCode and variableKey
KameleoonException.FeatureFlagEnvironmentDisabledFeature flag is disabled for the current environment
KameleoonException.JSONParseCouldn't parse JSON value
KameleoonException.NumberParseCouldn't parse Number value

Visitor data​

This section provides the methods you use to manage visitor data.

getVisitorCode()​

getVisitorCode method collected from useVisitorCode hook obtains a visitor code from the browser cookie. If the visitor code doesn't exist yet, the function generates a random visitor code (or uses the defaultVisitorCode value if you provided one) and sets the new visitor code in a cookie.

import { useEffect, useCallback } from 'react';
import { useInitialize, useVisitorCode } from '@kameleoon/react-sdk';

function MyComponent(): JSX.Element {
  const { initialize } = useInitialize();
  const { getVisitorCode } = useVisitorCode();

  const init = useCallback(async (): Promise<void> => {
    await initialize();

    // -- Get visitor code
    const visitorCode = getVisitorCode();

    // -- Pass default visitorCode, save and retrieve it
    const visitorCode = getVisitorCode('default_visitor_code');
  }, [initialize, getVisitorCode]);

  useEffect(() => {
    init();
  }, [init]);
}