feat: Enable use of project API key for default deployments

src/main/kotlin/Experiment.kt

@@ -17,7 +17,8 @@ object Experiment {
      * Initializes a singleton [RemoteEvaluationClient] instance. Subsequent calls will return the
      * same instance, regardless of api key or config.
      *
-     * @param apiKey  The API key. This can be found in the Experiment settings and should not be null or empty.
+     * @param apiKey  The Amplitude Project API key. This can be found in the Organization Settings -> Projects,
+     * and should not be null or empty. If a deployment key is provided in the config, it will be used instead.
      * @param config see [RemoteEvaluationConfig] for configuration options
      */
     @JvmStatic
@@ -26,14 +27,15 @@ object Experiment {
         apiKey: String,
         config: RemoteEvaluationConfig = RemoteEvaluationConfig()
     ): RemoteEvaluationClient = synchronized(remoteInstances) {
-        return when (val instance = remoteInstances[apiKey]) {
+        val usedKey = config.deploymentKey ?: apiKey
+        return when (val instance = remoteInstances[usedKey]) {
             null -> {
                 Logger.implementation = SystemLogger(config.debug)
                 val newInstance = RemoteEvaluationClient(
-                    apiKey,
+                    usedKey,
                     config,
                 )
-                remoteInstances[apiKey] = newInstance
+                remoteInstances[usedKey] = newInstance
                 newInstance
             }
             else -> instance
@@ -43,7 +45,8 @@ object Experiment {
      * Initializes a singleton [LocalEvaluationClient] instance. Subsequent calls will return the
      * same instance, regardless of api key or config.
      *
-     * @param apiKey  The API key. This can be found in the Experiment settings and should not be null or empty.
+     * @param apiKey  The Amplitude Project API key. This can be found in the Organization Settings -> Projects,
+     * and should not be null or empty. If a deployment key is provided in the config, it will be used instead.
      * @param config see [LocalEvaluationConfig] for configuration options
      */
     @JvmStatic
@@ -52,14 +55,15 @@ object Experiment {
         apiKey: String,
         config: LocalEvaluationConfig = LocalEvaluationConfig(),
     ): LocalEvaluationClient = synchronized(localInstances) {
+        val usedKey = config.deploymentKey ?: apiKey
         return when (val instance = localInstances[apiKey]) {
             null -> {
                 Logger.implementation = SystemLogger(config.debug)
                 val newInstance = LocalEvaluationClient(
-                    apiKey,
+                    usedKey,
                     config,
                 )
-                localInstances[apiKey] = newInstance
+                localInstances[usedKey] = newInstance
                 newInstance
             }
             else -> instance

src/main/kotlin/LocalEvaluationConfig.kt

@@ -17,6 +17,8 @@ class LocalEvaluationConfig internal constructor(
     val flagConfigPollerRequestTimeoutMillis: Long = Defaults.FLAG_CONFIG_POLLER_REQUEST_TIMEOUT_MILLIS,
     @JvmField
     val assignmentConfiguration: AssignmentConfiguration? = Defaults.ASSIGNMENT_CONFIGURATION,
+    @JvmField
+    val deploymentKey: String? = Defaults.DEPLOYMENT_KEY,
 ) {
 
     /**
@@ -53,6 +55,11 @@ class LocalEvaluationConfig internal constructor(
          * null
          */
         val ASSIGNMENT_CONFIGURATION: AssignmentConfiguration? = null
+
+        /**
+         * null
+         */
+        val DEPLOYMENT_KEY: String? = null
     }
 
     companion object {
@@ -69,6 +76,7 @@ class LocalEvaluationConfig internal constructor(
         private var flagConfigPollerIntervalMillis = Defaults.FLAG_CONFIG_POLLER_INTERVAL_MILLIS
         private var flagConfigPollerRequestTimeoutMillis = Defaults.FLAG_CONFIG_POLLER_REQUEST_TIMEOUT_MILLIS
         private var assignmentConfiguration = Defaults.ASSIGNMENT_CONFIGURATION
+        private var deploymentKey = Defaults.DEPLOYMENT_KEY
 
         fun debug(debug: Boolean) = apply {
             this.debug = debug
@@ -90,13 +98,18 @@ class LocalEvaluationConfig internal constructor(
             this.assignmentConfiguration = assignmentConfiguration
         }
 
+        fun deploymentKey(deploymentKey: String) = apply {
+            this.deploymentKey = deploymentKey
+        }
+
         fun build(): LocalEvaluationConfig {
             return LocalEvaluationConfig(
                 debug = debug,
                 serverUrl = serverUrl,
                 flagConfigPollerIntervalMillis = flagConfigPollerIntervalMillis,
                 flagConfigPollerRequestTimeoutMillis = flagConfigPollerRequestTimeoutMillis,
                 assignmentConfiguration = assignmentConfiguration,
+                deploymentKey = deploymentKey,
             )
         }
     }

src/main/kotlin/RemoteEvaluationConfig.kt

@@ -23,6 +23,8 @@ class RemoteEvaluationConfig internal constructor(
     val fetchRetryBackoffScalar: Double = Defaults.FETCH_RETRY_BACKOFF_SCALAR,
 //    @JvmField
 //    val fetchRetryTimeoutMillis: Long = Defaults.FETCH_RETRY_TIMEOUT_MILLIS,
+    @JvmField
+    val deploymentKey: String? = Defaults.DEPLOYMENT_KEY,
 ) {
 
     /**
@@ -49,18 +51,22 @@ class RemoteEvaluationConfig internal constructor(
          * 500
          */
         const val FETCH_TIMEOUT_MILLIS = 500L
+
         /**
          * 1
          */
         const val FETCH_RETRIES = 1
+
         /**
          * 0
          */
         const val FETCH_RETRY_BACKOFF_MIN_MILLIS = 0L
+
         /**
          * 10000
          */
         const val FETCH_RETRY_BACKOFF_MAX_MILLIS = 10000L
+
         /**
          * 1
          */
@@ -69,6 +75,10 @@ class RemoteEvaluationConfig internal constructor(
 //         * 500
 //         */
 //        const val FETCH_RETRY_TIMEOUT_MILLIS = 500L
+        /**
+         * null
+         */
+        val DEPLOYMENT_KEY = null
     }
 
     companion object {
@@ -88,6 +98,7 @@ class RemoteEvaluationConfig internal constructor(
         private var fetchRetryBackoffMaxMillis = Defaults.FETCH_RETRY_BACKOFF_MAX_MILLIS
         private var fetchRetryBackoffScalar = Defaults.FETCH_RETRY_BACKOFF_SCALAR
 //        private var fetchRetryTimeoutMillis = Defaults.FETCH_RETRY_TIMEOUT_MILLIS
+        private var deploymentKey: String? = Defaults.DEPLOYMENT_KEY
 
         fun debug(debug: Boolean) = apply {
             this.debug = debug
@@ -121,6 +132,10 @@ class RemoteEvaluationConfig internal constructor(
 //            this.fetchRetryTimeoutMillis = fetchRetryTimeoutMillis
 //        }
 
+        fun deploymentKey(deploymentKey: String) = apply {
+            this.deploymentKey = deploymentKey
+        }
+
         fun build(): RemoteEvaluationConfig {
             return RemoteEvaluationConfig(
                 debug = debug,
@@ -129,16 +144,17 @@ class RemoteEvaluationConfig internal constructor(
                 fetchRetries = fetchRetries,
                 fetchRetryBackoffMinMillis = fetchRetryBackoffMinMillis,
                 fetchRetryBackoffMaxMillis = fetchRetryBackoffMaxMillis,
-                fetchRetryBackoffScalar = fetchRetryBackoffScalar
+                fetchRetryBackoffScalar = fetchRetryBackoffScalar,
 //                fetchRetryTimeoutMillis = fetchRetryTimeoutMillis,
+                deploymentKey = deploymentKey
             )
         }
     }
 
     override fun toString(): String {
         return "ExperimentConfig(debug=$debug, serverUrl='$serverUrl', fetchTimeoutMillis=$fetchTimeoutMillis, " +
-            "fetchRetries=$fetchRetries, fetchRetryBackoffMinMillis=$fetchRetryBackoffMinMillis, " +
-            "fetchRetryBackoffMaxMillis=$fetchRetryBackoffMaxMillis, " +
-            "fetchRetryBackoffScalar=$fetchRetryBackoffScalar)"
+                "fetchRetries=$fetchRetries, fetchRetryBackoffMinMillis=$fetchRetryBackoffMinMillis, " +
+                "fetchRetryBackoffMaxMillis=$fetchRetryBackoffMaxMillis, " +
+                "fetchRetryBackoffScalar=$fetchRetryBackoffScalar)"
     }
 }