feat: provide client config property for region provider

.changes/05ac561b-963f-4953-bb4f-1fc19fc1207c.json

@@ -0,0 +1,8 @@
+{
+    "id": "05ac561b-963f-4953-bb4f-1fc19fc1207c",
+    "type": "feature",
+    "description": "Add `regionProvider` property to client config",
+    "issues": [
+        "awslabs/aws-sdk-kotlin#1478"
+    ]
+}

aws-runtime/aws-config/api/aws-config.api

@@ -222,6 +222,27 @@ public abstract class aws/sdk/kotlin/runtime/config/AbstractAwsSdkClientFactory
 	public static synthetic fun fromEnvironment$default (Laws/sdk/kotlin/runtime/config/AbstractAwsSdkClientFactory;Lkotlin/jvm/functions/Function1;Lkotlin/coroutines/Continuation;ILjava/lang/Object;)Ljava/lang/Object;
 }
 
+public abstract interface class aws/sdk/kotlin/runtime/config/AwsSdkClientConfig : aws/smithy/kotlin/runtime/client/SdkClientConfig {
+	public abstract fun getApplicationId ()Ljava/lang/String;
+	public abstract fun getRegion ()Ljava/lang/String;
+	public abstract fun getRegionProvider ()Laws/sdk/kotlin/runtime/region/RegionProvider;
+	public abstract fun getUseDualStack ()Z
+	public abstract fun getUseFips ()Z
+}
+
+public abstract interface class aws/sdk/kotlin/runtime/config/AwsSdkClientConfig$Builder {
+	public abstract fun getApplicationId ()Ljava/lang/String;
+	public abstract fun getRegion ()Ljava/lang/String;
+	public abstract fun getRegionProvider ()Laws/sdk/kotlin/runtime/region/RegionProvider;
+	public abstract fun getUseDualStack ()Ljava/lang/Boolean;
+	public abstract fun getUseFips ()Ljava/lang/Boolean;
+	public abstract fun setApplicationId (Ljava/lang/String;)V
+	public abstract fun setRegion (Ljava/lang/String;)V
+	public abstract fun setRegionProvider (Laws/sdk/kotlin/runtime/region/RegionProvider;)V
+	public abstract fun setUseDualStack (Ljava/lang/Boolean;)V
+	public abstract fun setUseFips (Ljava/lang/Boolean;)V
+}
+
 public final class aws/sdk/kotlin/runtime/config/AwsSdkSetting {
 	public static final field INSTANCE Laws/sdk/kotlin/runtime/config/AwsSdkSetting;
 	public final fun getAwsAccessKeyId ()Laws/smithy/kotlin/runtime/config/EnvironmentSetting;

aws-runtime/aws-config/common/src/aws/sdk/kotlin/runtime/config/AbstractAwsSdkClientFactory.kt

@@ -5,7 +5,6 @@
 
 package aws.sdk.kotlin.runtime.config
 
-import aws.sdk.kotlin.runtime.client.AwsSdkClientConfig
 import aws.sdk.kotlin.runtime.config.compression.resolveDisableRequestCompression
 import aws.sdk.kotlin.runtime.config.compression.resolveRequestMinCompressionSizeBytes
 import aws.sdk.kotlin.runtime.config.endpoints.resolveUseDualStack
@@ -74,7 +73,7 @@ public abstract class AbstractAwsSdkClientFactory<
             block?.let(config::apply)
 
             config.logMode = config.logMode ?: ClientSettings.LogMode.resolve(platform = platform)
-            config.region = config.region ?: resolveRegion(profile = profile)
+            config.region = config.region ?: config.regionProvider?.getRegion() ?: resolveRegion(profile = profile)
             config.useFips = config.useFips ?: resolveUseFips(profile = profile)
             config.useDualStack = config.useDualStack ?: resolveUseDualStack(profile = profile)
             config.applicationId = config.applicationId ?: resolveUserAgentAppId(platform, profile)

aws-runtime/aws-core/common/src/aws/sdk/kotlin/runtime/client/AwsSdkClientConfig.kt → aws-runtime/aws-config/common/src/aws/sdk/kotlin/runtime/config/AwsSdkClientConfig.kt

@@ -3,8 +3,9 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
-package aws.sdk.kotlin.runtime.client
+package aws.sdk.kotlin.runtime.config
 
+import aws.sdk.kotlin.runtime.region.RegionProvider
 import aws.smithy.kotlin.runtime.client.SdkClientConfig
 
 /**
@@ -19,6 +20,17 @@ public interface AwsSdkClientConfig : SdkClientConfig {
      */
     public val region: String?
 
+    /**
+     * An optional region provider that determines the AWS region for client operations. When specified, this provider
+     * takes precedence over the default region provider chain, unless a static region is explicitly configured.
+     *
+     * Region Resolution Priority:
+     * 1. Static region (if specified)
+     * 2. Custom region provider (if configured)
+     * 3. Default region provider chain
+     */
+    public val regionProvider: RegionProvider?
+
     /**
      * Flag to toggle whether to use [FIPS](https://aws.amazon.com/compliance/fips/) endpoints when making requests.
      * Disabled by default.
@@ -54,6 +66,17 @@ public interface AwsSdkClientConfig : SdkClientConfig {
          */
         public var region: String?
 
+        /**
+         * An optional region provider that determines the AWS region for client operations. When specified, this provider
+         * takes precedence over the default region provider chain, unless a static region is explicitly configured.
+         *
+         * Region Resolution Priority:
+         * 1. Static region (if specified)
+         * 2. Custom region provider (if configured)
+         * 3. Default region provider chain
+         */
+        public var regionProvider: RegionProvider?
+
         /**
          * Flag to toggle whether to use [FIPS](https://aws.amazon.com/compliance/fips/) endpoints when making requests.
          * Disabled by default.

aws-runtime/aws-config/jvm/test/aws/sdk/kotlin/runtime/config/AbstractAwsSdkClientFactoryTest.kt

@@ -5,10 +5,10 @@
 
 package aws.sdk.kotlin.runtime.config
 
-import aws.sdk.kotlin.runtime.client.AwsSdkClientConfig
 import aws.sdk.kotlin.runtime.config.profile.loadAwsSharedConfig
 import aws.sdk.kotlin.runtime.config.useragent.resolveUserAgentAppId
 import aws.sdk.kotlin.runtime.config.utils.mockPlatform
+import aws.sdk.kotlin.runtime.region.RegionProvider
 import aws.smithy.kotlin.runtime.client.*
 import aws.smithy.kotlin.runtime.retries.StandardRetryStrategy
 import aws.smithy.kotlin.runtime.util.PlatformProvider
@@ -129,6 +129,7 @@ private interface TestClient : SdkClient {
         override val clientName: String = builder.clientName
         override val logMode: LogMode = builder.logMode ?: LogMode.Default
         override val region: String? = builder.region
+        override var regionProvider: RegionProvider? = builder.regionProvider
         override var useFips: Boolean = builder.useFips ?: false
         override var useDualStack: Boolean = builder.useDualStack ?: false
         override val applicationId: String? = builder.applicationId
@@ -141,6 +142,7 @@ private interface TestClient : SdkClient {
             override var clientName: String = "Test"
             override var logMode: LogMode? = LogMode.Default
             override var region: String? = null
+            override var regionProvider: RegionProvider? = null
             override var useFips: Boolean? = null
             override var useDualStack: Boolean? = null
             override var applicationId: String? = null

aws-runtime/aws-core/api/aws-core.api

@@ -35,21 +35,3 @@ public final class aws/sdk/kotlin/runtime/client/AwsClientOption {
 	public final fun getRegion ()Laws/smithy/kotlin/runtime/collections/AttributeKey;
 }
 
-public abstract interface class aws/sdk/kotlin/runtime/client/AwsSdkClientConfig : aws/smithy/kotlin/runtime/client/SdkClientConfig {
-	public abstract fun getApplicationId ()Ljava/lang/String;
-	public abstract fun getRegion ()Ljava/lang/String;
-	public abstract fun getUseDualStack ()Z
-	public abstract fun getUseFips ()Z
-}
-
-public abstract interface class aws/sdk/kotlin/runtime/client/AwsSdkClientConfig$Builder {
-	public abstract fun getApplicationId ()Ljava/lang/String;
-	public abstract fun getRegion ()Ljava/lang/String;
-	public abstract fun getUseDualStack ()Ljava/lang/Boolean;
-	public abstract fun getUseFips ()Ljava/lang/Boolean;
-	public abstract fun setApplicationId (Ljava/lang/String;)V
-	public abstract fun setRegion (Ljava/lang/String;)V
-	public abstract fun setUseDualStack (Ljava/lang/Boolean;)V
-	public abstract fun setUseFips (Ljava/lang/Boolean;)V
-}
-

codegen/aws-sdk-codegen/src/main/kotlin/aws/sdk/kotlin/codegen/AwsRuntimeTypes.kt

@@ -16,10 +16,6 @@ object AwsRuntimeTypes {
         val AwsErrorMetadata = symbol("AwsErrorMetadata")
         val AwsServiceException = symbol("AwsServiceException")
         val ClientException = symbol("ClientException")
-
-        object Client : RuntimeTypePackage(AwsKotlinDependency.AWS_CORE, "client") {
-            val AwsSdkClientConfig = symbol("AwsSdkClientConfig")
-        }
     }
 
     object Endpoint : RuntimeTypePackage(AwsKotlinDependency.AWS_ENDPOINT) {
@@ -36,6 +32,8 @@ object AwsRuntimeTypes {
     object Config : RuntimeTypePackage(AwsKotlinDependency.AWS_CONFIG) {
         val AbstractAwsSdkClientFactory = symbol("AbstractAwsSdkClientFactory", "config")
 
+        val AwsSdkClientConfig = symbol("AwsSdkClientConfig", "config")
+
         object Endpoints : RuntimeTypePackage(AwsKotlinDependency.AWS_CONFIG, "config.endpoints") {
             val AccountIdEndpointMode = symbol("AccountIdEndpointMode")
             val resolveEndpointUrl = symbol("resolveEndpointUrl")
@@ -54,6 +52,11 @@ object AwsRuntimeTypes {
             val StaticCredentialsProvider = symbol("StaticCredentialsProvider")
             val manage = symbol("manage", "auth.credentials.internal", isExtension = true)
         }
+
+        object Region : RuntimeTypePackage(AwsKotlinDependency.AWS_CONFIG, "region") {
+            val RegionProvider = symbol("RegionProvider")
+            val resolveRegion = symbol("resolveRegion")
+        }
     }
 
     object Http : RuntimeTypePackage(AwsKotlinDependency.AWS_HTTP) {

codegen/aws-sdk-codegen/src/main/kotlin/aws/sdk/kotlin/codegen/AwsServiceConfigIntegration.kt

@@ -24,20 +24,33 @@ class AwsServiceConfigIntegration : KotlinIntegration {
         val RegionProp: ConfigProperty = ConfigProperty {
             name = "region"
             symbol = KotlinTypes.String.toBuilder().nullable().build()
-            baseClass = AwsRuntimeTypes.Core.Client.AwsSdkClientConfig
+            baseClass = AwsRuntimeTypes.Config.AwsSdkClientConfig
             useNestedBuilderBaseClass()
             documentation = """
                 The AWS region (e.g. `us-west-2`) to make requests to. See about AWS
                 [global infrastructure](https://aws.amazon.com/about-aws/global-infrastructure/regions_az/) for more
                 information
             """.trimIndent()
+
+            propertyType = ConfigPropertyType.Custom(
+                render = { prop, writer ->
+                    writer.write(
+                        "override val #1L: #2T? = builder.#1L ?: #3T { builder.regionProvider?.getRegion() ?: #4T() }",
+                        prop.propertyName,
+                        prop.symbol,
+                        KotlinTypes.Coroutines.runBlocking,
+                        AwsRuntimeTypes.Config.Region.resolveRegion,
+                    )
+                },
+            )
+
             order = -100
         }
 
         val UserAgentAppId: ConfigProperty = ConfigProperty {
             name = "applicationId"
             symbol = KotlinTypes.String.asNullable()
-            baseClass = AwsRuntimeTypes.Core.Client.AwsSdkClientConfig
+            baseClass = AwsRuntimeTypes.Config.AwsSdkClientConfig
             useNestedBuilderBaseClass()
             documentation = """
                  An optional application specific identifier.

codegen/aws-sdk-codegen/src/main/kotlin/aws/sdk/kotlin/codegen/RegionProviderIntegration.kt

@@ -0,0 +1,33 @@
+package aws.sdk.kotlin.codegen
+
+import software.amazon.smithy.kotlin.codegen.core.CodegenContext
+import software.amazon.smithy.kotlin.codegen.integration.KotlinIntegration
+import software.amazon.smithy.kotlin.codegen.model.asNullable
+import software.amazon.smithy.kotlin.codegen.rendering.util.ConfigProperty
+
+/**
+ * Adds region provider integration to the client config
+ */
+class RegionProviderIntegration : KotlinIntegration {
+    companion object {
+        val RegionProviderProp: ConfigProperty = ConfigProperty {
+            name = "regionProvider"
+            symbol = AwsRuntimeTypes.Config.Region.RegionProvider.asNullable()
+            baseClass = AwsRuntimeTypes.Config.AwsSdkClientConfig
+            useNestedBuilderBaseClass()
+            documentation = """
+              An optional region provider that determines the AWS region for client operations. When specified, this provider 
+              takes precedence over the default region provider chain, unless a static region is explicitly configured. 
+
+              The region resolution order is:
+              1. Static region (if specified)
+              2. Custom region provider (if configured)
+              3. Default region provider chain
+            """.trimIndent()
+        }
+    }
+
+    override fun additionalServiceConfigProps(ctx: CodegenContext): List<ConfigProperty> = buildList {
+        add(RegionProviderProp)
+    }
+}

codegen/aws-sdk-codegen/src/main/kotlin/aws/sdk/kotlin/codegen/endpoints/BindAwsEndpointBuiltins.kt

@@ -38,7 +38,7 @@ class BindAwsEndpointBuiltins : KotlinIntegration {
                 Flag to toggle whether to use [FIPS](https://aws.amazon.com/compliance/fips/) endpoints when making requests.
      `          Disabled by default.
             """.trimIndent()
-            baseClass = AwsRuntimeTypes.Core.Client.AwsSdkClientConfig
+            baseClass = AwsRuntimeTypes.Config.AwsSdkClientConfig
             useNestedBuilderBaseClass()
         }
 
@@ -50,7 +50,7 @@ class BindAwsEndpointBuiltins : KotlinIntegration {
                 See [https://docs.aws.amazon.com/sdkref/latest/guide/feature-endpoints.html] for more information.
      `          Disabled by default.
             """.trimIndent()
-            baseClass = AwsRuntimeTypes.Core.Client.AwsSdkClientConfig
+            baseClass = AwsRuntimeTypes.Config.AwsSdkClientConfig
             useNestedBuilderBaseClass()
         }
     }

codegen/aws-sdk-codegen/src/main/resources/META-INF/services/software.amazon.smithy.kotlin.codegen.integration.KotlinIntegration

@@ -2,6 +2,7 @@ aws.sdk.kotlin.codegen.AddUserAgentMetadataIntegration
 aws.sdk.kotlin.codegen.AwsServiceConfigIntegration
 aws.sdk.kotlin.codegen.GradleGenerator
 aws.sdk.kotlin.codegen.AwsRetryHeaderIntegration
+aws.sdk.kotlin.codegen.RegionProviderIntegration
 aws.sdk.kotlin.codegen.customization.ReplaceServiceExceptionBase
 aws.sdk.kotlin.codegen.customization.DefaultMiddleware
 aws.sdk.kotlin.codegen.customization.AccountIdEndpointBuiltinCustomization

codegen/aws-sdk-codegen/src/test/kotlin/aws/sdk/kotlin/codegen/AwsServiceConfigIntegrationTest.kt

@@ -45,7 +45,7 @@ class AwsServiceConfigIntegrationTest {
         val contents = writer.toString()
 
         val expectedProps = """
-    override val region: String? = builder.region
+    override val region: String? = builder.region ?: runBlocking { builder.regionProvider?.getRegion() ?: resolveRegion() }
     override val credentialsProvider: CredentialsProvider = builder.credentialsProvider ?: DefaultChainCredentialsProvider(httpClient = httpClient, region = region).manage()
 """
         contents.shouldContainOnlyOnceWithDiff(expectedProps)

tests/codegen/event-stream/build.gradle.kts

@@ -94,6 +94,9 @@ tasks.generateSmithyProjections {
         // ensure the generated tests use the same version of the runtime as the aws aws-runtime
         val smithyKotlinRuntimeVersion = libs.versions.smithy.kotlin.runtime.version.get()
         System.setProperty("smithy.kotlin.codegen.clientRuntimeVersion", smithyKotlinRuntimeVersion)
+
+        val smithyKotlinCoroutinesVersion = libs.versions.coroutines.version.get()
+        System.setProperty("smithy.kotlin.codegen.kotlinCoroutinesVersion", smithyKotlinCoroutinesVersion)
     }
 }