feat: add JVM property region provider (#295)

Author: aajtodd

aws-runtime/auth/common/src/aws/sdk/kotlin/runtime/auth/CredentialsProvider.kt

@@ -15,5 +15,3 @@ public interface CredentialsProvider {
      */
     public suspend fun getCredentials(): Credentials
 }
-
-// TODO - add proxies for all the credentials providers in aws-crt-kotlin

aws-runtime/auth/common/src/aws/sdk/kotlin/runtime/auth/EnvironmentCredentialsProvider.kt

@@ -5,6 +5,7 @@
 
 package aws.sdk.kotlin.runtime.auth
 
+import aws.sdk.kotlin.runtime.AwsSdkSetting
 import aws.sdk.kotlin.runtime.ConfigurationException
 import aws.smithy.kotlin.runtime.util.Platform
 
@@ -13,20 +14,14 @@ import aws.smithy.kotlin.runtime.util.Platform
  */
 public class EnvironmentCredentialsProvider
 public constructor(private val getEnv: (String) -> String?) : CredentialsProvider {
-    public companion object {
-        internal const val ACCESS_KEY_ID: String = "AWS_ACCESS_KEY_ID"
-        internal const val SECRET_ACCESS_KEY: String = "AWS_SECRET_ACCESS_KEY"
-        internal const val SESSION_TOKEN: String = "AWS_SESSION_TOKEN"
-    }
-
     public constructor() : this(Platform::getenv)
 
     private fun requireEnv(variable: String): String =
         getEnv(variable) ?: throw ConfigurationException("Unable to get value from environment variable $variable")
 
     override suspend fun getCredentials(): Credentials = Credentials(
-        accessKeyId = requireEnv(ACCESS_KEY_ID),
-        secretAccessKey = requireEnv(SECRET_ACCESS_KEY),
-        sessionToken = getEnv(SESSION_TOKEN),
+        accessKeyId = requireEnv(AwsSdkSetting.AwsAccessKeyId.environmentVariable),
+        secretAccessKey = requireEnv(AwsSdkSetting.AwsSecretAccessKey.environmentVariable),
+        sessionToken = getEnv(AwsSdkSetting.AwsSessionToken.environmentVariable),
     )
 }

aws-runtime/auth/common/test/aws/sdk/kotlin/runtime/auth/EnvironmentCredentialsProviderTest.kt

@@ -5,6 +5,7 @@
 
 package aws.sdk.kotlin.runtime.auth
 
+import aws.sdk.kotlin.runtime.AwsSdkSetting
 import aws.sdk.kotlin.runtime.ConfigurationException
 import aws.sdk.kotlin.runtime.testing.runSuspendTest
 import kotlin.test.Test
@@ -17,33 +18,33 @@ class EnvironmentCredentialsProviderTest {
     @Test
     fun `it should read from environment variables (incl session token)`() = runSuspendTest {
         val provider = provider(
-            EnvironmentCredentialsProvider.ACCESS_KEY_ID to "abc",
-            EnvironmentCredentialsProvider.SECRET_ACCESS_KEY to "def",
-            EnvironmentCredentialsProvider.SESSION_TOKEN to "ghi",
+            AwsSdkSetting.AwsAccessKeyId.environmentVariable to "abc",
+            AwsSdkSetting.AwsSecretAccessKey.environmentVariable to "def",
+            AwsSdkSetting.AwsSessionToken.environmentVariable to "ghi",
         )
         assertEquals(provider.getCredentials(), Credentials("abc", "def", "ghi"))
     }
 
     @Test
     fun `it should read from environment variables (excl session token)`() = runSuspendTest {
         val provider = provider(
-            EnvironmentCredentialsProvider.ACCESS_KEY_ID to "abc",
-            EnvironmentCredentialsProvider.SECRET_ACCESS_KEY to "def",
+            AwsSdkSetting.AwsAccessKeyId.environmentVariable to "abc",
+            AwsSdkSetting.AwsSecretAccessKey.environmentVariable to "def",
         )
         assertEquals(provider.getCredentials(), Credentials("abc", "def", null))
     }
 
     @Test
-    fun `it should throw an exception on missing access key`() = runSuspendTest {
+    fun `it should throw an exception on missing access key`(): Unit = runSuspendTest {
         assertFailsWith<ConfigurationException> {
-            provider(EnvironmentCredentialsProvider.SECRET_ACCESS_KEY to "def").getCredentials()
+            provider(AwsSdkSetting.AwsSecretAccessKey.environmentVariable to "def").getCredentials()
         }
     }
 
     @Test
-    fun `it should throw an exception on missing secret key`() = runSuspendTest {
+    fun `it should throw an exception on missing secret key`(): Unit = runSuspendTest {
         assertFailsWith<ConfigurationException> {
-            provider(EnvironmentCredentialsProvider.ACCESS_KEY_ID to "abc").getCredentials()
+            provider(AwsSdkSetting.AwsAccessKeyId.environmentVariable to "abc").getCredentials()
         }
     }
 }

aws-runtime/aws-core/common/src/aws/sdk/kotlin/runtime/AwsSdkSetting.kt

@@ -0,0 +1,54 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0.
+ */
+
+package aws.sdk.kotlin.runtime
+
+// NOTE: The JVM property names MUST match the ones defined in the Java SDK for any setting added.
+// see: https://github.com/aws/aws-sdk-java-v2/blob/master/core/sdk-core/src/main/java/software/amazon/awssdk/core/SdkSystemSetting.java
+
+/**
+ * Settings to configure SDK runtime behavior
+ */
+@InternalSdkApi
+public sealed class AwsSdkSetting<T> (
+    /**
+     * The name of the corresponding environment variable that configures the setting
+     */
+    public val environmentVariable: String,
+
+    /**
+     * The name of the corresponding JVM system property that configures the setting
+     */
+    public val jvmProperty: String,
+
+    /**
+     * The default value (if one exists)
+     */
+    public val defaultValue: T? = null
+) {
+    /**
+     * Configure the AWS access key ID.
+     *
+     * This value will not be ignored if the [AwsSecretAccessKey] is not specified.
+     */
+    public object AwsAccessKeyId : AwsSdkSetting<String>("AWS_ACCESS_KEY_ID", "aws.accessKeyId")
+
+    /**
+     * Configure the AWS secret access key.
+     *
+     * This value will not be ignored if the [AwsAccessKeyId] is not specified.
+     */
+    public object AwsSecretAccessKey : AwsSdkSetting<String>("AWS_SECRET_ACCESS_KEY", "aws.secretAccessKey")
+
+    /**
+     * Configure the AWS session token.
+     */
+    public object AwsSessionToken : AwsSdkSetting<String>("AWS_SESSION_TOKEN", "aws.sessionToken")
+
+    /**
+     * Configure the default region.
+     */
+    public object AwsRegion : AwsSdkSetting<String>("AWS_REGION", "aws.region")
+}

aws-runtime/regions/common/src/aws/sdk/kotlin/runtime/regions/providers/DefaultAwsRegionProviderChain.kt

@@ -5,15 +5,11 @@
 
 package aws.sdk.kotlin.runtime.regions.providers
 
-// FIXME - this probably needs to be expect/actual to customize the chain per/target platform (and definitely needs per/platform tests)
-
 /**
  * [AwsRegionProvider] that looks for region in this order:
  *  1. Check `aws.region` system property (JVM only)
- *  2. Check the `AWS_REGION` and `AWS_DEFAULT_REGION` environment variable(s) (JVM, Node, Native)
+ *  2. Check the `AWS_REGION` environment variable (JVM, Node, Native)
  *  3. Check the AWS config files/profile for region information
  *  4. If running on EC2, check the EC2 metadata service for region
  */
-public class DefaultAwsRegionProviderChain : AwsRegionProviderChain {
-    public constructor() : super(EnvironmentRegionProvider())
-}
+public expect class DefaultAwsRegionProviderChain public constructor() : AwsRegionProvider

aws-runtime/regions/common/src/aws/sdk/kotlin/runtime/regions/providers/EnvironmentRegionProvider.kt

@@ -5,10 +5,9 @@
 
 package aws.sdk.kotlin.runtime.regions.providers
 
+import aws.sdk.kotlin.runtime.AwsSdkSetting
 import aws.smithy.kotlin.runtime.util.Platform
 
-private const val AWS_ENVIRON_REGION = "AWS_REGION"
-
 /**
  * Provide a mapping from key to value
  */
@@ -17,13 +16,13 @@ public fun interface Environment {
 }
 
 /**
- * [AwsRegionProvider] that checks `AWS_REGION` and `AWS_DEFAULT` region environment variables
+ * [AwsRegionProvider] that checks `AWS_REGION` region environment variable
  * @param environ the environment mapping to lookup keys in (defaults to the system environment)
  */
 public class EnvironmentRegionProvider(
     private val environ: Environment
 ) : AwsRegionProvider {
     public constructor() : this(Platform::getenv)
 
-    override suspend fun getRegion(): String? = environ.get(AWS_ENVIRON_REGION)
+    override suspend fun getRegion(): String? = environ.get(AwsSdkSetting.AwsRegion.environmentVariable)
 }

aws-runtime/regions/jvm/src/aws/sdk/kotlin/runtime/regions/providers/DefaultAwsRegionProviderChainJVM.kt

@@ -0,0 +1,13 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0.
+ */
+
+package aws.sdk.kotlin.runtime.regions.providers
+
+public actual class DefaultAwsRegionProviderChain public actual constructor() :
+    AwsRegionProvider,
+    AwsRegionProviderChain(
+        JvmSystemPropRegionProvider(),
+        EnvironmentRegionProvider()
+    )

aws-runtime/regions/jvm/src/aws/sdk/kotlin/runtime/regions/providers/JvmSystemPropRegionProvider.kt

@@ -0,0 +1,15 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0.
+ */
+
+package aws.sdk.kotlin.runtime.regions.providers
+
+import aws.sdk.kotlin.runtime.AwsSdkSetting
+
+/**
+ * [AwsRegionProvider] that checks `aws.region` system property
+ */
+internal class JvmSystemPropRegionProvider : AwsRegionProvider {
+    override suspend fun getRegion(): String? = System.getProperty(AwsSdkSetting.AwsRegion.jvmProperty, null)
+}

aws-runtime/regions/jvm/test/aws/sdk/kotlin/runtime/regions/providers/JvmSystemPropRegionProviderTest.kt

@@ -0,0 +1,25 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0.
+ */
+
+package aws.sdk.kotlin.runtime.regions.providers
+
+import aws.sdk.kotlin.runtime.AwsSdkSetting
+import aws.sdk.kotlin.runtime.testing.runSuspendTest
+import org.junit.jupiter.api.Test
+import kotlin.test.assertEquals
+import kotlin.test.assertNull
+
+class JvmSystemPropRegionProviderTest {
+
+    @Test
+    fun testGetRegion() = runSuspendTest {
+        val provider = JvmSystemPropRegionProvider()
+
+        assertNull(provider.getRegion())
+
+        System.setProperty(AwsSdkSetting.AwsRegion.jvmProperty, "us-east-1")
+        assertEquals("us-east-1", provider.getRegion())
+    }
+}