feat: Add DynamoDB provider to parameters module

docs/utilities/parameters.md

@@ -5,8 +5,9 @@ description: Utility
 
 
 The parameters utility provides a way to retrieve parameter values from
-[AWS Systems Manager Parameter Store](https://docs.aws.amazon.com/systems-manager/latest/userguide/systems-manager-parameter-store.html) or
-[AWS Secrets Manager](https://aws.amazon.com/secrets-manager/). It also provides a base class to create your parameter provider implementation.
+[AWS Systems Manager Parameter Store](https://docs.aws.amazon.com/systems-manager/latest/userguide/systems-manager-parameter-store.html), 
+[AWS Secrets Manager](https://aws.amazon.com/secrets-manager/), or [Amazon DynamoDB](https://aws.amazon.com/dynamodb/). 
+It also provides a base class to create your parameter provider implementation.
 
 **Key features**
 
@@ -40,11 +41,12 @@ To install this utility, add the following dependency to your project.
 
 This utility requires additional permissions to work as expected. See the table below:
 
-Provider | Function/Method | IAM Permission
-------------------------------------------------- | ------------------------------------------------- | ---------------------------------------------------------------------------------
-SSM Parameter Store | `SSMProvider.get(String)` `SSMProvider.get(String, Class)` | `ssm:GetParameter`
-SSM Parameter Store | `SSMProvider.getMultiple(String)` | `ssm:GetParametersByPath`
-Secrets Manager | `SecretsProvider.get(String)` `SecretsProvider.get(String, Class)` | `secretsmanager:GetSecretValue`
+Provider | Function/Method | IAM Permission
+------------------------------------------------- |----------------------------------------------------------------------| ---------------------------------------------------------------------------------
+SSM Parameter Store | `SSMProvider.get(String)` `SSMProvider.get(String, Class)` | `ssm:GetParameter`
+SSM Parameter Store | `SSMProvider.getMultiple(String)` | `ssm:GetParametersByPath`
+Secrets Manager | `SecretsProvider.get(String)` `SecretsProvider.get(String, Class)` | `secretsmanager:GetSecretValue`
+DynamoDB | `DynamoDBProvider.get(String)` `DynamoDBProvider.getMultiple(string)` | `dynamodb:GetItem` `dynamoDB:Query`
 
 ## SSM Parameter Store
 
@@ -166,6 +168,52 @@ in order to get data from other regions or use specific credentials.
  }
  ```
 
+## DynamoDB 
+To get secrets stored in DynamoDB, use `getDynamoDbProvider`, providing the name of the table that
+contains the secrets. As with the other providers, an overloaded methods allows you to retrieve 
+a `DynamoDbProvider` providing a client if you need to configure it yourself. 
+
+=== "DynamoDbProvider"
+
+ ```java hl_lines="6 9"
+ import software.amazon.lambda.powertools.parameters.DynamoDbProvider;
+ import software.amazon.lambda.powertools.parameters.ParamManager;
+
+ public class AppWithDynamoDbParameters implements RequestHandler<APIGatewayProxyRequestEvent, APIGatewayProxyResponseEvent> {
+ // Get an instance of the DynamoDbProvider
+ DynamoDbProvider ddbProvider = ParamManager.getDynamoDbProvider("my-parameters-table");
+
+ // Retrieve a single parameter
+ String value = ddbProvider.get("my-key"); 
+ } 
+ ```
+
+=== "DynamoDbProvider with an explicit region"
+
+ ```java hl_lines="9 10 11 12 15 18"
+ import software.amazon.lambda.powertools.parameters.DynamoDbProvider;
+ import software.amazon.lambda.powertools.parameters.ParamManager;
+ import software.amazon.awssdk.services.dynamodb.DynamoDbClient;
+ import software.amazon.awssdk.http.urlconnection.UrlConnectionHttpClient;
+ import software.amazon.awssdk.regions.Region;
+
+ public class AppWithDynamoDbParameters implements RequestHandler<APIGatewayProxyRequestEvent, APIGatewayProxyResponseEvent> {
+ // Get a DynamoDB Client with an explicit region
+ DynamoDbClient ddbClient = DynamoDbClient.builder()
+ .httpClientBuilder(UrlConnectionHttpClient.builder())
+ .region(Region.EU_CENTRAL_2)
+ .build();
+
+ // Get an instance of the DynamoDbProvider
+ DynamoDbProvider provider = ParamManager.getDynamoDbProvider(ddbClient, "test-table");
+
+ // Retrieve a single parameter
+ String value = ddbProvider.get("my-key"); 
+ } 
+ ```
+
+
+
 ## Advanced configuration
 
 ### Caching

powertools-parameters/pom.xml

@@ -73,6 +73,10 @@
  <groupId>software.amazon.awssdk</groupId>
  <artifactId>url-connection-client</artifactId>
  </dependency>
+ <dependency>
+ <groupId>software.amazon.awssdk</groupId>
+ <artifactId>dynamodb</artifactId>
+ </dependency>
  <dependency>
  <groupId>com.fasterxml.jackson.core</groupId>
  <artifactId>jackson-databind</artifactId>

powertools-parameters/src/main/java/software/amazon/lambda/powertools/parameters/DynamoDbProvider.java

@@ -0,0 +1,179 @@
+package software.amazon.lambda.powertools.parameters;
+
+import software.amazon.awssdk.auth.credentials.EnvironmentVariableCredentialsProvider;
+import software.amazon.awssdk.core.SdkSystemSetting;
+import software.amazon.awssdk.http.urlconnection.UrlConnectionHttpClient;
+import software.amazon.awssdk.regions.Region;
+import software.amazon.awssdk.services.dynamodb.DynamoDbClient;
+import software.amazon.awssdk.services.dynamodb.model.*;
+import software.amazon.lambda.powertools.parameters.cache.CacheManager;
+import software.amazon.lambda.powertools.parameters.transform.TransformationManager;
+
+import java.util.Collections;
+import java.util.Map;
+import java.util.stream.Collectors;
+
+/**
+ * Implements a {@link ParamProvider} on top of DynamoDB. The schema of the table
+ * is described in the Python powertools documentation.
+ *
+ * @see <a href="https://awslabs.github.io/aws-lambda-powertools-python/latest/utilities/parameters/#dynamodbprovider">Python DynamoDB provider</a>
+ *
+ */
+public class DynamoDbProvider extends BaseProvider {
+
+ private final DynamoDbClient client;
+ private final String tableName;
+
+ public DynamoDbProvider(CacheManager cacheManager, String tableName) {
+ this(cacheManager, DynamoDbClient.builder()
+ .httpClientBuilder(UrlConnectionHttpClient.builder())
+ .credentialsProvider(EnvironmentVariableCredentialsProvider.create())
+ .region(Region.of(System.getenv(SdkSystemSetting.AWS_REGION.environmentVariable())))
+ .build(),
+ tableName
+ );
+
+ }
+
+ DynamoDbProvider(CacheManager cacheManager, DynamoDbClient client, String tableName) {
+ super(cacheManager);
+ this.client = client;
+ this.tableName = tableName;
+ }
+
+ /**
+ * Return a single value from the DynamoDB parameter provider.
+ *
+ * @param key key of the parameter
+ * @return The value, if it exists, null if it doesn't. Throws if the row exists but doesn't match the schema.
+ */
+ @Override
+ protected String getValue(String key) {
+ GetItemResponse resp = client.getItem(GetItemRequest.builder()
+ .tableName(tableName)
+ .key(Collections.singletonMap("id", AttributeValue.fromS(key)))
+ .attributesToGet("val")
+ .build());
+
+ // If we have an item at the key, we should be able to get a 'val' out of it. If not it's
+ // exceptional.
+ // If we don't have an item at the key, we should return null.
+ if (resp.hasItem() && !resp.item().values().isEmpty()) {
+ return resp.item().get("val").s();
+ }
+
+ return null;
+ }
+
+ /**
+ * Returns multiple values from the DynamoDB parameter provider.
+ *
+ * @param path Parameter store path
+ * @return All values matching the given path, and an empty map if none do. Throws if any records exist that don't match the schema.
+ */
+ @Override
+ protected Map<String, String> getMultipleValues(String path) {
+
+ QueryResponse resp = client.query(QueryRequest.builder()
+ .tableName(tableName)
+ .keyConditionExpression("id = :v_id")
+ .expressionAttributeValues(Collections.singletonMap(":v_id", AttributeValue.fromS(path)))
+ .build());
+
+ return resp
+ .items()
+ .stream()
+ .collect(
+ Collectors.toMap(
+ (i) -> i.get("sk").s(),
+ (i) -> i.get("val").s()));
+
+
+ }
+
+ /**
+ * Create a builder that can be used to configure and create a {@link DynamoDbProvider}.
+ *
+ * @return a new instance of {@link DynamoDbProvider.Builder}
+ */
+ public static DynamoDbProvider.Builder builder() {
+ return new DynamoDbProvider.Builder();
+ }
+
+ static class Builder {
+ private DynamoDbClient client;
+ private String table;
+ private CacheManager cacheManager;
+ private TransformationManager transformationManager;
+
+ /**
+ * Create a {@link DynamoDbProvider} instance.
+ *
+ * @return a {@link DynamoDbProvider}
+ */
+ public DynamoDbProvider build() {
+ if (cacheManager == null) {
+ throw new IllegalStateException("No CacheManager provided; please provide one");
+ }
+ if (table == null) {
+ throw new IllegalStateException("No DynamoDB table name provided; please provide one");
+ }
+ DynamoDbProvider provider;
+ if (client != null) {
+ provider = new DynamoDbProvider(cacheManager, client, table);
+ } else {
+ provider = new DynamoDbProvider(cacheManager, table);
+ }
+ if (transformationManager != null) {
+ provider.setTransformationManager(transformationManager);
+ }
+ return provider;
+ }
+
+ /**
+ * Set custom {@link DynamoDbClient} to pass to the {@link DynamoDbClient}. <br/>
+ * Use it if you want to customize the region or any other part of the client.
+ *
+ * @param client Custom client
+ * @return the builder to chain calls (eg. <pre>builder.withClient().build()</pre>)
+ */
+ public DynamoDbProvider.Builder withClient(DynamoDbClient client) {
+ this.client = client;
+ return this;
+ }
+
+ /**
+ * <b>Mandatory</b>. Provide a CacheManager to the {@link DynamoDbProvider}
+ *
+ * @param cacheManager the manager that will handle the cache of parameters
+ * @return the builder to chain calls (eg. <pre>builder.withCacheManager().build()</pre>)
+ */
+ public DynamoDbProvider.Builder withCacheManager(CacheManager cacheManager) {
+ this.cacheManager = cacheManager;
+ return this;
+ }
+
+ /**
+ * <b>Mandatory</b>. Provide a DynamoDB table to the {@link DynamoDbProvider}
+ *
+ * @param table the table that parameters will be retrieved from.
+ * @return the builder to chain calls (eg. <pre>builder.withTable().build()</pre>)
+ */
+ public DynamoDbProvider.Builder withTable(String table) {
+ this.table = table;
+ return this;
+ }
+
+ /**
+ * Provide a transformationManager to the {@link DynamoDbProvider}
+ *
+ * @param transformationManager the manager that will handle transformation of parameters
+ * @return the builder to chain calls (eg. <pre>builder.withTransformationManager().build()</pre>)
+ */
+ public DynamoDbProvider.Builder withTransformationManager(TransformationManager transformationManager) {
+ this.transformationManager = transformationManager;
+ return this;
+ }
+ }
+}

powertools-parameters/src/main/java/software/amazon/lambda/powertools/parameters/ParamManager.java

@@ -15,6 +15,7 @@
 
 import software.amazon.awssdk.services.secretsmanager.SecretsManagerClient;
 import software.amazon.awssdk.services.ssm.SsmClient;
+import software.amazon.awssdk.services.dynamodb.DynamoDbClient;
 import software.amazon.lambda.powertools.parameters.cache.CacheManager;
 import software.amazon.lambda.powertools.parameters.transform.TransformationManager;
 
@@ -36,8 +37,8 @@ public final class ParamManager {
 
  /**
  * Get a concrete implementation of {@link BaseProvider}.<br/>
- * You can specify {@link SecretsProvider} or {@link SSMProvider} or create your custom provider
- * by extending {@link BaseProvider} if you need to integrate with a different parameter store.
+ * You can specify {@link SecretsProvider}, {@link SSMProvider}, {@link DynamoDbProvider}, or create your
+ * custom provider by extending {@link BaseProvider} if you need to integrate with a different parameter store.
  * @return a {@link SecretsProvider}
  */
  public static <T extends BaseProvider> T getProvider(Class<T> providerClass) {
@@ -65,6 +66,21 @@ public static SSMProvider getSsmProvider() {
  return getProvider(SSMProvider.class);
  }
 
+ /**
+ * Get a {@link DynamoDbProvider} with default {@link DynamoDbClient} <br/>
+ * If you need to customize the region, or other part of the client, use {@link ParamManager#getDynamoDbProvider(DynamoDbClient, String)}
+ */
+ public static DynamoDbProvider getDynamoDbProvider(String tableName) {
+ // Because we need a DDB table name to configure our client, we can't use
+ // ParamManager#getProvider. This means that we need to make sure we do the same stuff -
+ // set transformation manager and cache manager.
+ return DynamoDbProvider.builder()
+ .withCacheManager(cacheManager)
+ .withTable(tableName)
+ .withTransformationManager(transformationManager)
+ .build();
+ }
+
  /**
  * Get a {@link SecretsProvider} with your custom {@link SecretsManagerClient}.<br/>
  * Use this to configure region or other part of the client. Use {@link ParamManager#getSsmProvider()} if you don't need this customization.
@@ -91,6 +107,20 @@ public static SSMProvider getSsmProvider(SsmClient client) {
  .build());
  }
 
+ /**
+ * Get a {@link DynamoDbProvider} with your custom {@link DynamoDbClient}.<br/>
+ * Use this to configure region or other part of the client. Use {@link ParamManager#getDynamoDbProvider(String)} )} if you don't need this customization.
+ * @return a {@link DynamoDbProvider}
+ */
+ public static DynamoDbProvider getDynamoDbProvider(DynamoDbClient client, String table) {
+ return (DynamoDbProvider) providers.computeIfAbsent(DynamoDbProvider.class, (k) -> DynamoDbProvider.builder()
+ .withClient(client)
+ .withTable(table)
+ .withCacheManager(cacheManager)
+ .withTransformationManager(transformationManager)
+ .build());
+ }
+
  public static CacheManager getCacheManager() {
  return cacheManager;
  }