---
title: OptimizelyConfig for the PHP SDK
slug: feature-experimentation/docs/optimizelyconfig-php
docTags: 
createdAt: 2026-08-05T20:39:57.000Z
---

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.

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

### Get `OptimizelyConfig`

You can access `OptimizelyConfig` through the `OptimizelyClient` (top-level) using this public API call.

```php
$config = $optimizelyClient->getOptimizelyConfig();
```

`getOptimizelyConfig` returns an `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
- Function to retrieve the project configuration (the datafile)

:::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 ensure that multiple SDK instances all instantiate from the same configuration (for example, in a client and server scenario), you can pass a JSON string representation of the config (the datafile) between the instances. To get the datafile, use the `OptimizelyConfig` object's `getDatafile` method. For information, see [Sharing the datafile with multiple SDK implementations](docId\:eH-UMm_rOn_GdGDGLV6__).

### Object model

The following sample shows the object model for `OptimizelyConfig`:

```php
/**
 * OptimizelyConfig is an object describing the current project configuration data being used by this SDK instance.
 * @typedef {string} environmentKey
 * @typedef {string} sdkKey
 * @typedef {string} revision
 * 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.
 * @property {Object.<string, OptimizelyExperiment>}} experimentsMap
 * @property {Object.<string, OptimizelyFeature>}} featuresMap
 * @property [Object.<string, OptimizelyAttribute>}] attributes
 * @property [Object.<string, OptimizelyAudience>}] audiences
 * @property [Object.<string, OptimizelyEvent>}] events               
 */


/**
 * OptimizelyFeature is an object describing a feature flag
 * @typedef {Object} OptimizelyFeature
 * @property {string} id
 * @property {string} key
 * @property [Object.<string, OptimizelyExperiment>}] experimentRules
 * @property [Object.<string, OptimizelyExperiment>}] deliveryRules
 * Use experimentRules and deliveryRules
 * @property {Object.<string, OptimizelyExperiment>}} experimentsMap
 * @property {Object.<string, OptimizelyVariable>}} variablesMap
 */

/**
 * OptimizelyExperiment is an object describing an experiment
 * @typedef {Object} OptimizelyExperiment
 * @property {string} id
 * @property {string} key
 * @property {string} audiences
 * @property {Object.<string, OptimizelyVariation>}} variationMap
 */


/**
 * OptimizelyVariation is an object describing a variation in an experiment
 * @typedef {Object} OptimizelyVariation
 * @property {string} id
 * @property {string} key
 * @property {boolean=} featureEnabled
 * @property {Object.<string, OptimizelyVariable>}} variablesMap
 */

/**
 * OptimizelyVariable is an object describing a feature flag variable
 * @typedef {Object} OptimizelyVariable
 * @property {string} id
 * @property {string} key
 * @property {string} type
 * @property {string} value
 */

/**
 * OptimizelyAttribute is an object describing an attribute
 * @typedef {Object} OptimizelyAttribute
 * @property {string} id
 * @property {string} key
 */

/**
 * OptimizelyAudience is an object describing an audience
 * @typedef {Object} OptimizelyAudience
 * @property {string} id
 * @property {string} name
 * @property {string} conditions 
 */

/**
 * OptimizelyEvent is an object describing an event
 * @typedef {Object} OptimizelyEvent
 * @property {string} id
 * @property {string} key
 * @property {array} experimentIds 
 */
```

## Examples

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

```php
$config = $optimizelyClient->getOptimizelyConfig();
// get the revision
echo "[OptimizelyConfig] revision:" . $config->getRevision();

// get the SDK key
echo "[OptimizelyConfig] SDKKey:" . $config->getSdkKey();

// get the environment key
echo "[OptimizelyConfig] environmentKey:" . $config->getEnvironmentKey();

// all attributes
echo "[OptimizelyConfig] attributes:";
$attributes = $config->getAttributes();
foreach($attributes as $attribute)
{
    echo "[OptimizelyAttribute]   -- (id, key) = ((" . $attribute->getId(). "), (". $attribute->getKey() . "))";
}

// all audiences
echo "[OptimizelyConfig] audiences:";
$audiences = $config->getAudiences();
foreach($audiences as $audience)
{
    echo "[OptimizelyAudience]   -- (id, key, conditions) = ((" . $audience->getId(). "), (". $audience->getName() . "), (". $audience->getConditions() . "))";
}

// all events
echo "[OptimizelyConfig] events:";
$events = $config->getEvents();
foreach($events as $event)
{
    echo "[OptimizelyEvent]   -- (id, key, experimentIds) = ((" . $event->getId(). "), (". $event->getKey() . "), (". $event->getExperimentIds() . "))";
}

// all flags
$flags = array_values((array)$config->getFeaturesMap());
foreach ($flags as $flag)
{
    // Use  experimentRules and deliveryRules
    $experimentRules = $flag->getExperimentRules();
    foreach ($experimentRules as $experimentRule)
    {
    echo "[OptimizelyExperiment]   - experiment rule-key = " . $experimentRule->getKey();
    echo "[OptimizelyExperiment]   - experiment audiences = " . $experimentRule->getExperimentAudiences();
        // all variations
        $variations = array_values((array)$experimentRule->getVariationsMap());
        foreach ($variations as $variation)
        {
            echo "[OptimizelyVariation]       -- variation = { key: " . $variation->getKey() . ", id: " . $variation->getId() . ", featureEnabled: " . $variation->getFeatureEnabled() . " }";
            $variables = $variation->getVariablesMap();
            foreach ($variables as $variable)
            {
                echo "[OptimizelyVariable]           --- variable: " . $variable->getKey() . ", " . $variable->getId();
            // use variable data here.
            }
            // use experimentRule data here.
        }
    }
    $deliveryRules = $flag->getDeliveryRules();
    foreach ($deliveryRules as $deliveryRule)
    {
        echo "[OptimizelyExperiment]   - delivery rule-key = " . $deliveryRule->getKey();
        echo "[OptimizelyExperiment]   - delivery audiences = " . $deliveryRule->getExperimentAudiences();

        // use delivery rule data here...
    }
}
$optimizelyClient->notificationCenter->addNotificationListener(
    NotificationType::OPTIMIZELY_CONFIG_UPDATE,
    function () {
        $newConfig = $optimizelyClient->getOptimizelyConfig();
        echo "[OptimizelyConfig] revision = " . $newConfig ? $newConfig->getRevision() : "";
    }
);
```