Merge pull request #2 from ethkatnic/provider-decoder-improvements

Multilang - Provider Decoder Improvements

amazon-kinesis-client-multilang/src/main/java/software/amazon/kinesis/multilang/config/AwsCredentialsProviderPropertyValueDecoder.java

@@ -27,6 +27,8 @@ import java.util.stream.Stream;
 import lombok.extern.slf4j.Slf4j;
 import software.amazon.awssdk.auth.credentials.AwsCredentialsProvider;
 import software.amazon.awssdk.auth.credentials.AwsCredentialsProviderChain;
+import software.amazon.awssdk.services.sts.auth.StsAssumeRoleCredentialsProvider;
+import software.amazon.kinesis.multilang.auth.KclStsAssumeRoleCredentialsProvider;
 
 /**
  * Get AwsCredentialsProvider property.
@@ -79,58 +81,17 @@ class AwsCredentialsProviderPropertyValueDecoder implements IPropertyValueDecode
 
         for (String providerName : providerNames) {
             final String[] nameAndArgs = providerName.split("\\" + ARG_DELIMITER);
-            final Class<? extends AwsCredentialsProvider> clazz;
+            final Class<? extends AwsCredentialsProvider> clazz = getClass(nameAndArgs[0]);
-            try {
+            if (clazz == null) {
-                final Class<?> c = Class.forName(nameAndArgs[0]);
-                if (!AwsCredentialsProvider.class.isAssignableFrom(c)) {
-                    continue;
-                }
-                clazz = (Class<? extends AwsCredentialsProvider>) c;
-            } catch (ClassNotFoundException cnfe) {
-                // Providers are a product of prefixed Strings to cover multiple
-                // namespaces (e.g., "Foo" -> { "some.auth.Foo", "kcl.auth.Foo" }).
-                // It's expected that many class names will not resolve.
                 continue;
             }
             log.info("Attempting to construct {}", clazz);
-
+            final String[] varargs =
-            AwsCredentialsProvider provider = null;
+                    nameAndArgs.length > 1 ? Arrays.copyOfRange(nameAndArgs, 1, nameAndArgs.length) : new String[0];
-            if (nameAndArgs.length > 1) {
+            AwsCredentialsProvider provider = tryConstructor(providerName, clazz, varargs);
-                final String[] varargs = Arrays.copyOfRange(nameAndArgs, 1, nameAndArgs.length);
-
-                // attempt to invoke an explicit N-arg constructor of FooClass(String, String, ...)
-                provider = constructProvider(providerName, () -> {
-                    Class<?>[] argTypes = new Class<?>[nameAndArgs.length - 1];
-                    Arrays.fill(argTypes, String.class);
-                    return clazz.getConstructor(argTypes).newInstance(varargs);
-                });
-
-                if (provider == null) {
-                    // attempt to invoke a public varargs/array constructor of FooClass(String[])
-                    provider = constructProvider(providerName, () -> clazz.getConstructor(String[].class)
-                            .newInstance((Object) varargs));
-                }
-            }
-
             if (provider == null) {
-                // regardless of parameters, fallback to invoke a public no-arg constructor
+                provider = tryCreate(providerName, clazz, varargs);
-                provider = constructProvider(providerName, clazz::newInstance);
             }
-
-            if (provider == null) {
-                // if still not found, try empty create() method
-                try {
-                    Method createMethod = clazz.getDeclaredMethod("create");
-                    if (Modifier.isStatic(createMethod.getModifiers())) {
-                        provider = constructProvider(providerName, () -> clazz.cast(createMethod.invoke(null)));
-                    } else {
-                        log.warn("Found non-static create() method in {}", providerName);
-                    }
-                } catch (NoSuchMethodException e) {
-                    // No create() method found for class
-                }
-            }
-
             if (provider != null) {
                 credentialsProviders.add(provider);
             }
@@ -138,6 +99,101 @@ class AwsCredentialsProviderPropertyValueDecoder implements IPropertyValueDecode
         return credentialsProviders;
     }
 
+    private static AwsCredentialsProvider tryConstructor(
+            String providerName, Class<? extends AwsCredentialsProvider> clazz, String[] varargs) {
+        AwsCredentialsProvider provider =
+                constructProvider(providerName, () -> getConstructorWithVarArgs(clazz, varargs));
+        if (provider == null) {
+            provider = constructProvider(providerName, () -> getConstructorWithArgs(clazz, varargs));
+        }
+        if (provider == null) {
+            provider = constructProvider(providerName, clazz::newInstance);
+        }
+        return provider;
+    }
+
+    private static AwsCredentialsProvider tryCreate(
+            String providerName, Class<? extends AwsCredentialsProvider> clazz, String[] varargs) {
+        AwsCredentialsProvider provider =
+                constructProvider(providerName, () -> getCreateMethod(clazz, (Object) varargs));
+        if (provider == null) {
+            provider = constructProvider(providerName, () -> getCreateMethod(clazz, varargs));
+        }
+        if (provider == null) {
+            provider = constructProvider(providerName, () -> getCreateMethod(clazz));
+        }
+        return provider;
+    }
+
+    private static AwsCredentialsProvider getConstructorWithVarArgs(
+            Class<? extends AwsCredentialsProvider> clazz, String[] varargs) {
+        try {
+            return clazz.getConstructor(String[].class).newInstance((Object) varargs);
+        } catch (Exception e) {
+            return null;
+        }
+    }
+
+    private static AwsCredentialsProvider getConstructorWithArgs(
+            Class<? extends AwsCredentialsProvider> clazz, String[] varargs) {
+        try {
+            Class<?>[] argTypes = new Class<?>[varargs.length];
+            Arrays.fill(argTypes, String.class);
+            return clazz.getConstructor(argTypes).newInstance((Object[]) varargs);
+        } catch (Exception e) {
+            return null;
+        }
+    }
+
+    private static AwsCredentialsProvider getCreateMethod(
+            Class<? extends AwsCredentialsProvider> clazz, Object... args) {
+        try {
+            Class<?>[] argTypes = new Class<?>[args.length];
+            for (int i = 0; i < args.length; i++) {
+                argTypes[i] = args[i].getClass();
+            }
+            Method createMethod = clazz.getDeclaredMethod("create", argTypes);
+            if (Modifier.isStatic(createMethod.getModifiers())) {
+                return clazz.cast(createMethod.invoke(null, args));
+            } else {
+                log.warn("Found non-static create() method in {}", clazz.getName());
+            }
+        } catch (NoSuchMethodException e) {
+            // No matching create method found for class
+        } catch (Exception e) {
+            log.warn("Failed to invoke create() method in {}", clazz.getName(), e);
+        }
+        return null;
+    }
+
+    /**
+     * Resolves the class for the given provider name.
+     *
+     * @param providerName A string containing the provider name.
+     *
+     * @return The Class object representing the resolved AwsCredentialsProvider implementation,
+     * or null if the class cannot be resolved or does not extend AwsCredentialsProvider.
+     */
+    private static Class<? extends AwsCredentialsProvider> getClass(String providerName) {
+        // Convert any form of StsAssumeRoleCredentialsProvider string to KclStsAssumeRoleCredentialsProvider
+        if (providerName.equals(StsAssumeRoleCredentialsProvider.class.getSimpleName())
+                || providerName.equals(StsAssumeRoleCredentialsProvider.class.getName())) {
+            providerName = KclStsAssumeRoleCredentialsProvider.class.getName();
+        }
+        try {
+            final Class<?> c = Class.forName(providerName);
+            if (!AwsCredentialsProvider.class.isAssignableFrom(c)) {
+                return null;
+            }
+            return (Class<? extends AwsCredentialsProvider>) c;
+        } catch (ClassNotFoundException cnfe) {
+            // Providers are a product of prefixed Strings to cover multiple
+            // namespaces (e.g., "Foo" -> { "some.auth.Foo", "kcl.auth.Foo" }).
+            // It's expected that many class names will not resolve.
+            return null;
+        }
+    }
+
     private static List<String> getProviderNames(String property) {
         // assume list delimiter is ","
         String[] elements = property.split(LIST_DELIMITER);

amazon-kinesis-client-multilang/src/test/java/software/amazon/kinesis/multilang/config/AWSCredentialsProviderPropertyValueDecoderTest.java

@@ -25,6 +25,7 @@ import software.amazon.awssdk.auth.credentials.AwsBasicCredentials;
 import software.amazon.awssdk.auth.credentials.AwsCredentials;
 import software.amazon.awssdk.auth.credentials.AwsCredentialsProvider;
 import software.amazon.awssdk.auth.credentials.AwsCredentialsProviderChain;
+import software.amazon.awssdk.services.sts.auth.StsAssumeRoleCredentialsProvider;
 import software.amazon.kinesis.multilang.auth.KclStsAssumeRoleCredentialsProvider;
 
 import static org.hamcrest.CoreMatchers.equalTo;
@@ -40,6 +41,7 @@ public class AWSCredentialsProviderPropertyValueDecoderTest {
 
     private final String credentialName1 = AlwaysSucceedCredentialsProvider.class.getName();
     private final String credentialName2 = ConstructorCredentialsProvider.class.getName();
+    private final String createCredentialClass = CreateProvider.class.getName();
     private final AwsCredentialsProviderPropertyValueDecoder decoder = new AwsCredentialsProviderPropertyValueDecoder();
 
     @ToString
@@ -119,13 +121,32 @@ public class AWSCredentialsProviderPropertyValueDecoderTest {
     public void testKclAuthProvider() {
         for (final String className : Arrays.asList(
                 KclStsAssumeRoleCredentialsProvider.class.getName(), // fully-qualified name
-                KclStsAssumeRoleCredentialsProvider.class.getSimpleName() // name-only; needs prefix
+                KclStsAssumeRoleCredentialsProvider.class.getSimpleName(), // name-only; needs prefix
-                )) {
+                StsAssumeRoleCredentialsProvider.class.getName(), // user passes full sts package path
+                StsAssumeRoleCredentialsProvider.class.getSimpleName())) {
             final AwsCredentialsProvider provider = decoder.decodeValue(className + "|arn|sessionName");
             assertNotNull(className, provider);
         }
     }
 
+    /**
+     * Test that OneArgCreateProvider in the SDK v2 can process a create() method
+     */
+    @Test
+    public void testEmptyCreateProvider() {
+        AwsCredentialsProvider provider = decoder.decodeValue(createCredentialClass);
+        assertThat(provider, hasCredentials(TEST_ACCESS_KEY_ID, TEST_SECRET_KEY));
+    }
+
+    /**
+     * Test that OneArgCreateProvider in the SDK v2 can process a create(arg1) method
+     */
+    @Test
+    public void testOneArgCreateProvider() {
+        AwsCredentialsProvider provider = decoder.decodeValue(createCredentialClass + "|testCreateProperty");
+        assertThat(provider, hasCredentials("testCreateProperty", TEST_SECRET_KEY));
+    }
+
     /**
      * Test that a provider can be instantiated by its varargs constructor.
      */
@@ -188,4 +209,28 @@ public class AWSCredentialsProviderPropertyValueDecoderTest {
             return AwsBasicCredentials.create(flattenedArgs, flattenedArgs);
         }
     }
+
+    /**
+     * Credentials provider to test AWS SDK v2 create() methods for providers like ProfileCredentialsProvider
+     */
+    public static class CreateProvider implements AwsCredentialsProvider {
+        private String accessKeyId;
+
+        private CreateProvider(String accessKeyId) {
+            this.accessKeyId = accessKeyId;
+        }
+
+        public static CreateProvider create() {
+            return new CreateProvider(TEST_ACCESS_KEY_ID);
+        }
+
+        public static CreateProvider create(String accessKeyId) {
+            return new CreateProvider(accessKeyId);
+        }
+
+        @Override
+        public AwsCredentials resolveCredentials() {
+            return AwsBasicCredentials.create(accessKeyId, TEST_SECRET_KEY);
+        }
+    }
 }

docs/multilang/configuring-credential-providers.md

@@ -7,23 +7,28 @@ However, KCL now provides better extensibility to handle, and be enhanced to han
 This document should help multilang customers configure a suitable `CredentialProvider` (or contribute changes to support a new use case!).
 
 ## Sample Provider Configuration
-DEPRECATED: StsAssumeRoleCredentialsProvider can no longer be constructed in this way:
-```
-AWSCredentialsProvider = StsAssumeRoleCredentialsProvider|<arn>|<sessionName>`
-```
 
-To create a [StsAssumeRoleCredentialsProvider][sts-assume-provider], see KclStsAssumeRoleCredentialsProvider below.
+In a Properties file, an `AWSCredentialsProperty` configuration might look like:
+```
+AWSCredentialsProvider = StsAssumeRoleCredentialsProvider|<arn>|<sessionName> 
+```
+This basic configuration creates an [StsAssumeRoleCredentialsProvider][sts-assume-provider] with an ARN and session name.
 
-You can create a default [DefaultCredentialsProvider][default-credentials-provider] or [AnonymousCredentialsProvider][anonymous-credentials-provider]
+While functional, this configuration is limited.
-by passing it in the config like:
+For example, this configuration cannot set a regional endpoint (e.g., VPC use case).
+
+Leveraging nested properties, an `AWSCredentialsProperty` value might change to:
+```
+AWSCredentialsProvider = KclSTSAssumeRoleSessionCredentialsProvider|<arn>|<sessionName>\
+    |endpointRegion=us-east-1|externalId=spartacus
+```
+N.B. Backslash (`\`) is for multi-line legibility and is not required.
+
+You can create a default [DefaultCredentialsProvider][default-credentials-provider] by passing it in the config like:
 ```
 AWSCredentialsProvider = DefaultCredentialsProvider
 ```
 
-If you wish to customize properties on an AWS SDK provider that uses a builder, like the StsASsumeRoleCredentialsProvider,
-you will need to wrap this provider class, provide a constructor, and manage the build of the provider. 
-See implementation of [KclStsAssumeRoleCredentialsProvider][kcl-sts-provider]
-
 ## Nested Properties
 
 KCL multilang supports "nested properties" on the `AWSCredentialsProvider` key in the properties file.
@@ -37,6 +42,10 @@ The [Backus-Naur form][bnf] of the value:
 <nested-value ::= <string> # this depends on the nested key
 ```
 
+In general, required parameters are passed directly to the class' constructor or .create() method
+(e.g., [ProfileCredentialsProvider(String)][profile-credentials-provider-create]). However, most of these providers
+require builders and will require a custom implementation similar to `KclStsAssumeRoleCredentialsProvider` for customization
+
 Nested properties are a custom mapping provided by KCL multilang, and do not exist in the AWS SDK.
 See [NestedPropertyKey][nested-property-key] for the supported keys, and details on their expected values.
 
@@ -73,5 +82,5 @@ AWSCredentialsProvider = KclStsAssumeRoleCredentialsProvider|<arn>|<sessionName>
 [nested-property-key]: /amazon-kinesis-client-multilang/src/main/java/software/amazon/kinesis/multilang/NestedPropertyKey.java
 [nested-property-processor]: /amazon-kinesis-client-multilang/src/main/java/software/amazon/kinesis/multilang/NestedPropertyProcessor.java
 [sts-assume-provider]: https://sdk.amazonaws.com/java/api/latest/software/amazon/awssdk/services/sts/auth/StsAssumeRoleCredentialsProvider.html
+[profile-credentials-provider-create]: https://sdk.amazonaws.com/java/api/latest/software/amazon/awssdk/auth/credentials/ProfileCredentialsProvider.html#create(java.lang.String)
 [default-credentials-provider]: https://sdk.amazonaws.com/java/api/latest/software/amazon/awssdk/auth/credentials/DefaultCredentialsProvider.html
-[anonymous-credentials-provider]: https://sdk.amazonaws.com/java/api/2.0.0-preview-11/software/amazon/awssdk/auth/credentials/AnonymousCredentialsProvider.html