update based on comments

core/src/main/kotlin/com/expediagroup/sdk/core/client/BaseRapidClient.kt

@@ -23,7 +23,6 @@ import com.expediagroup.sdk.core.plugin.authentication.strategy.AuthenticationSt
 import io.ktor.client.HttpClient
 import io.ktor.client.engine.HttpClientEngine
 import io.ktor.client.engine.okhttp.OkHttp
-import okhttp3.OkHttpClient
 
 /**
  * The integration point between the SDK Core and the product SDKs.
@@ -42,7 +41,7 @@ abstract class BaseRapidClient(
             RapidConfigurationProvider
         )
 
-    private val engine: HttpClientEngine = clientConfiguration.okHttpClient?.let {
+    private val engine: HttpClientEngine = _configurationProvider.okHttpClient?.let {
         OkHttp.create {
             preconfigured = it
         }
@@ -66,17 +65,5 @@ abstract class BaseRapidClient(
 
     /** A [BaseRapidClient] builder with ability to pass a custom okhttp client. */
     @Suppress("unused", "UnnecessaryAbstractClass") // This is used by the generated SDK clients.
-    abstract class BuilderWithHttpClient<SELF : Client.Builder<SELF>> : Client.Builder<SELF>() {
-        protected var okHttpClient: OkHttpClient? = null
-
-        @Suppress("UNCHECKED_CAST")
-        override fun self(): SELF = this as SELF
-
-        /** Sets the [OkHttpClient] to use for the [BaseRapidClient]. */
-        fun okHttpClient(okHttpClient: OkHttpClient): SELF {
-            this.okHttpClient = okHttpClient
-            return self()
-        }
-
-    }
+    abstract class BuilderWithHttpClient<SELF : Client.BuilderWithHttpClient<SELF>> : Client.BuilderWithHttpClient<SELF>()
 }

core/src/main/kotlin/com/expediagroup/sdk/core/client/BaseXapClient.kt

@@ -23,7 +23,6 @@ import com.expediagroup.sdk.core.plugin.authentication.strategy.AuthenticationSt
 import io.ktor.client.HttpClient
 import io.ktor.client.engine.HttpClientEngine
 import io.ktor.client.engine.okhttp.OkHttp
-import okhttp3.OkHttpClient
 
 /**
  * The integration point between the SDK Core and the product SDKs.
@@ -42,7 +41,7 @@ abstract class BaseXapClient(
             XapConfigurationProvider
         )
 
-    private val engine: HttpClientEngine = clientConfiguration.okHttpClient?.let {
+    private val engine: HttpClientEngine = _configurationProvider.okHttpClient?.let {
         OkHttp.create {
             preconfigured = it
         }
@@ -66,17 +65,5 @@ abstract class BaseXapClient(
 
     /** A [BaseXapClient] builder with ability to pass a custom okhttp client. */
     @Suppress("unused", "UnnecessaryAbstractClass") // This is used by the generated SDK clients.
-    abstract class BuilderWithHttpClient<SELF : Client.Builder<SELF>> : Client.Builder<SELF>() {
-        protected var okHttpClient: OkHttpClient? = null
-
-        @Suppress("UNCHECKED_CAST")
-        override fun self(): SELF = this as SELF
-
-        /** Sets the [OkHttpClient] to use for the [BaseXapClient]. */
-        fun okHttpClient(okHttpClient: OkHttpClient): SELF {
-            this.okHttpClient = okHttpClient
-            return self()
-        }
-
-    }
+    abstract class BuilderWithHttpClient<SELF : Client.BuilderWithHttpClient<SELF>> : Client.BuilderWithHttpClient<SELF>()
 }

core/src/main/kotlin/com/expediagroup/sdk/core/client/Client.kt

@@ -51,6 +51,7 @@ import io.ktor.client.engine.okhttp.OkHttp
 import io.ktor.client.statement.HttpResponse
 import io.ktor.client.statement.request
 import okhttp3.Dispatcher
+import okhttp3.OkHttpClient
 
 // Create a Dispatcher with limits
 val dispatcher = Dispatcher().apply {
@@ -309,12 +310,30 @@ abstract class Client(
 
         /** Create a [Client] object. */
         abstract override fun build(): Client
-
     }
 
+
+    /**
+     * A builder class for configuring HTTP-related settings for a [Client] with the ability to pass a custom [OkHttpClient].
+     *
+     * This builder class extends the base [Client.Builder] class and provides additional methods
+     * for setting a configured okhttp client.
+     *
+     * @param <SELF> The type of the builder itself, used for method chaining.
+     */
+    abstract class BuilderWithHttpClient<SELF : Builder<SELF>> : Builder<SELF>() {
+        protected var okHttpClient: OkHttpClient? = null
+
+        @Suppress("UNCHECKED_CAST")
+        override fun self(): SELF = this as SELF
+
+        /** Sets the [OkHttpClient] to use for the [Client]. */
+        fun okHttpClient(okHttpClient: OkHttpClient): SELF {
+            this.okHttpClient = okHttpClient
+            return self()
+        }
+    }
 }
 
 /** Executes the hooks for the client. */
 fun <T : Client> T.finalize() = Hooks.execute(this)
-
-

core/src/main/kotlin/com/expediagroup/sdk/core/configuration/ClientConfiguration.kt

@@ -16,6 +16,7 @@
 package com.expediagroup.sdk.core.configuration
 
 import com.expediagroup.sdk.core.configuration.provider.RuntimeConfigurationProvider
+import okhttp3.OkHttpClient
 
 interface ClientConfiguration {
     val key: String?
@@ -26,6 +27,7 @@ interface ClientConfiguration {
     val socketTimeout: Long?
     val maskedLoggingHeaders: Set<String>?
     val maskedLoggingBodyFields: Set<String>?
+    val okHttpClient: OkHttpClient?
 
     /** Build a [RuntimeConfigurationProvider] from a [ClientConfiguration]. */
     fun toProvider(): RuntimeConfigurationProvider =
@@ -37,6 +39,7 @@ interface ClientConfiguration {
             connectionTimeout = connectionTimeout,
             socketTimeout = socketTimeout,
             maskedLoggingHeaders = maskedLoggingHeaders,
-            maskedLoggingBodyFields = maskedLoggingBodyFields
+            maskedLoggingBodyFields = maskedLoggingBodyFields,
+            okHttpClient = okHttpClient
         )
 }

core/src/main/kotlin/com/expediagroup/sdk/core/configuration/ExpediaGroupClientConfiguration.kt

@@ -17,6 +17,7 @@ package com.expediagroup.sdk.core.configuration
 
 import com.expediagroup.sdk.core.client.ExpediaGroupClient
 import com.expediagroup.sdk.core.configuration.provider.RuntimeConfigurationProvider
+import okhttp3.OkHttpClient
 
 /**
  * Configuration for the [ExpediaGroupClient].
@@ -30,6 +31,7 @@ import com.expediagroup.sdk.core.configuration.provider.RuntimeConfigurationProv
  * @property maskedLoggingHeaders The headers to be masked in logging.
  * @property maskedLoggingBodyFields The body fields to be masked in logging.
  * @property authEndpoint The API endpoint to use for authentication.
+ * @property okHttpClient The okhttp client to be used by the sdk.
  */
 data class ExpediaGroupClientConfiguration(
     override val key: String? = null,
@@ -40,6 +42,7 @@ data class ExpediaGroupClientConfiguration(
     override val socketTimeout: Long? = null,
     override val maskedLoggingHeaders: Set<String>? = null,
     override val maskedLoggingBodyFields: Set<String>? = null,
+    override val okHttpClient: OkHttpClient? = null,
     val authEndpoint: String? = null
 ) : ClientConfiguration {
     /** Build a [RuntimeConfigurationProvider] from an [ExpediaGroupClientConfiguration]. */

core/src/main/kotlin/com/expediagroup/sdk/core/configuration/RapidClientConfiguration.kt

@@ -39,5 +39,5 @@ data class RapidClientConfiguration(
     override val socketTimeout: Long? = null,
     override val maskedLoggingHeaders: Set<String>? = null,
     override val maskedLoggingBodyFields: Set<String>? = null,
-    val okHttpClient: OkHttpClient? = null
+    override val okHttpClient: OkHttpClient? = null
 ) : ClientConfiguration

core/src/main/kotlin/com/expediagroup/sdk/core/configuration/XapClientConfiguration.kt

@@ -39,5 +39,5 @@ data class XapClientConfiguration(
     override val socketTimeout: Long? = null,
     override val maskedLoggingHeaders: Set<String>? = null,
     override val maskedLoggingBodyFields: Set<String>? = null,
-    val okHttpClient: OkHttpClient? = null
+    override val okHttpClient: OkHttpClient? = null
 ) : ClientConfiguration

core/src/main/kotlin/com/expediagroup/sdk/core/configuration/collector/ConfigurationCollector.kt

@@ -28,6 +28,7 @@ import com.expediagroup.sdk.core.constant.ConfigurationName.SECRET
 import com.expediagroup.sdk.core.constant.ConfigurationName.SOCKET_TIMEOUT_MILLIS
 import com.expediagroup.sdk.core.constant.provider.LoggingMessageProvider
 import com.expediagroup.sdk.core.plugin.logging.ExpediaGroupLoggerFactory
+import okhttp3.OkHttpClient
 
 /**
  * Configuration collector that collects configuration from all available providers.
@@ -66,6 +67,7 @@ internal class ConfigurationCollector private constructor(providers: Configurati
     override val socketTimeout: Long? = providers.firstWith { it.socketTimeout }.also { it?.log(SOCKET_TIMEOUT_MILLIS) }?.retrieve()
     override val maskedLoggingHeaders: Set<String>? = providers.firstWith { it.maskedLoggingHeaders }.also { it?.log(MASKED_LOGGING_HEADERS) }?.retrieve()
     override val maskedLoggingBodyFields: Set<String>? = providers.firstWith { it.maskedLoggingBodyFields }.also { it?.log(MASKED_LOGGING_BODY_FIELDS) }?.retrieve()
+    override val okHttpClient: OkHttpClient? = providers.firstWith { it.okHttpClient }?.retrieve()
 
     private fun <T> ProvidedConfiguration<T>.log(configurationName: String) {
         log.info(LoggingMessageProvider.getChosenProviderMessage(configurationName, providerName))

core/src/main/kotlin/com/expediagroup/sdk/core/configuration/provider/ConfigurationProvider.kt

@@ -16,6 +16,7 @@
 package com.expediagroup.sdk.core.configuration.provider
 
 import com.expediagroup.sdk.core.constant.Constant
+import okhttp3.OkHttpClient
 
 /**
  * A configuration provider that can be used to provide configuration values.
@@ -55,4 +56,8 @@ interface ConfigurationProvider {
     /** The body fields to be masked in logging.*/
     val maskedLoggingBodyFields: Set<String>?
         get() = setOf()
+
+    /** The okhttp client to be used by the sdk.*/
+    val okHttpClient: OkHttpClient?
+        get() = null
 }

core/src/main/kotlin/com/expediagroup/sdk/core/configuration/provider/RuntimeConfigurationProvider.kt

@@ -16,6 +16,7 @@
 package com.expediagroup.sdk.core.configuration.provider
 
 import com.expediagroup.sdk.core.constant.ConfigurationName.RUNTIME_CONFIGURATION_PROVIDER
+import okhttp3.OkHttpClient
 
 /**
  * A runtime-built configuration provider.
@@ -41,5 +42,6 @@ data class RuntimeConfigurationProvider(
     override val connectionTimeout: Long? = null,
     override val socketTimeout: Long? = null,
     override val maskedLoggingHeaders: Set<String>? = null,
-    override val maskedLoggingBodyFields: Set<String>? = null
+    override val maskedLoggingBodyFields: Set<String>? = null,
+    override val okHttpClient: OkHttpClient? = null
 ) : ConfigurationProvider

core/src/test/kotlin/com/expediagroup/sdk/core/configuration/ExpediaGroupClientConfigurationTest.kt

@@ -32,6 +32,7 @@ class ExpediaGroupClientConfigurationTest {
             assertNull(it.socketTimeout)
             assertNull(it.maskedLoggingHeaders)
             assertNull(it.maskedLoggingBodyFields)
+            assertNull(it.okHttpClient)
         }
     }
 
@@ -72,6 +73,7 @@ class ExpediaGroupClientConfigurationTest {
             assertNull(it.socketTimeout)
             assertNull(it.maskedLoggingHeaders)
             assertNull(it.maskedLoggingBodyFields)
+            assertNull(it.okHttpClient)
         }
     }
 

generator/openapi/src/main/resources/templates/expediagroup-sdk/client.mustache

@@ -22,7 +22,7 @@ import kotlinx.coroutines.runBlocking
 class {{clientClassname}}Client private constructor(clientConfiguration: ExpediaGroupClientConfiguration) : ExpediaGroupClient("{{namespace}}", clientConfiguration) {
     class Builder : ExpediaGroupClient.Builder<Builder>() {
         override fun build() = {{clientClassname}}Client(
-            ExpediaGroupClientConfiguration(key, secret, endpoint, requestTimeout, connectionTimeout, socketTimeout, maskedLoggingHeaders, maskedLoggingBodyFields, authEndpoint)
+            ExpediaGroupClientConfiguration(key, secret, endpoint, requestTimeout, connectionTimeout, socketTimeout, maskedLoggingHeaders, maskedLoggingBodyFields, null, authEndpoint)
         )
     }