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Crea e gestisci tabelle globali DynamoDB dimostrando MREC utilizzando un SDK AWS
Il seguente esempio di codice mostra come creare e gestire tabelle globali DynamoDB con repliche in più regioni.
Crea una tabella con Global Secondary Index e DynamoDB Streams.
Aggiungi repliche in diverse regioni per creare una tabella globale.
Rimuovi le repliche da una tabella globale.
Aggiungi elementi di test per verificare la replica tra le regioni.
Descrivi la configurazione globale della tabella e lo stato della replica.
- Java
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- SDK per Java 2.x
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Crea una tabella con Global Secondary Index e DynamoDB Streams utilizzando. AWS SDK for Java 2.x
public static CreateTableResponse createTableWithGSI( final DynamoDbClient dynamoDbClient, final String tableName, final String indexName) { if (dynamoDbClient == null) { throw new IllegalArgumentException("DynamoDB client cannot be null"); } if (tableName == null || tableName.trim().isEmpty()) { throw new IllegalArgumentException("Table name cannot be null or empty"); } if (indexName == null || indexName.trim().isEmpty()) { throw new IllegalArgumentException("Index name cannot be null or empty"); } try { LOGGER.info("Creating table: " + tableName + " with GSI: " + indexName); CreateTableRequest createTableRequest = CreateTableRequest.builder() .tableName(tableName) .attributeDefinitions( AttributeDefinition.builder() .attributeName("Artist") .attributeType(ScalarAttributeType.S) .build(), AttributeDefinition.builder() .attributeName("SongTitle") .attributeType(ScalarAttributeType.S) .build()) .keySchema( KeySchemaElement.builder() .attributeName("Artist") .keyType(KeyType.HASH) .build(), KeySchemaElement.builder() .attributeName("SongTitle") .keyType(KeyType.RANGE) .build()) .billingMode(BillingMode.PAY_PER_REQUEST) .globalSecondaryIndexes(GlobalSecondaryIndex.builder() .indexName(indexName) .keySchema(KeySchemaElement.builder() .attributeName("SongTitle") .keyType(KeyType.HASH) .build()) .projection( Projection.builder().projectionType(ProjectionType.ALL).build()) .build()) .streamSpecification(StreamSpecification.builder() .streamEnabled(true) .streamViewType(StreamViewType.NEW_AND_OLD_IMAGES) .build()) .build(); CreateTableResponse response = dynamoDbClient.createTable(createTableRequest); LOGGER.info("Table creation initiated. Status: " + response.tableDescription().tableStatus()); return response; } catch (DynamoDbException e) { LOGGER.severe("Failed to create table: " + tableName + " - " + e.getMessage()); throw e; } }
Attendi che una tabella diventi attiva utilizzando. AWS SDK for Java 2.x
public static void waitForTableActive(final DynamoDbClient dynamoDbClient, final String tableName) { if (dynamoDbClient == null) { throw new IllegalArgumentException("DynamoDB client cannot be null"); } if (tableName == null || tableName.trim().isEmpty()) { throw new IllegalArgumentException("Table name cannot be null or empty"); } try { LOGGER.info("Waiting for table to become active: " + tableName); try (DynamoDbWaiter waiter = DynamoDbWaiter.builder().client(dynamoDbClient).build()) { DescribeTableRequest request = DescribeTableRequest.builder().tableName(tableName).build(); waiter.waitUntilTableExists(request); LOGGER.info("Table is now active: " + tableName); } } catch (DynamoDbException e) { LOGGER.severe("Failed to wait for table to become active: " + tableName + " - " + e.getMessage()); throw e; } }
Aggiungi una replica per creare o estendere una tabella globale utilizzando AWS SDK for Java 2.x.
public static UpdateTableResponse addReplica( final DynamoDbClient dynamoDbClient, final String tableName, final Region replicaRegion, final String indexName, final Long readCapacity) { if (dynamoDbClient == null) { throw new IllegalArgumentException("DynamoDB client cannot be null"); } if (tableName == null || tableName.trim().isEmpty()) { throw new IllegalArgumentException("Table name cannot be null or empty"); } if (replicaRegion == null) { throw new IllegalArgumentException("Replica region cannot be null"); } if (indexName == null || indexName.trim().isEmpty()) { throw new IllegalArgumentException("Index name cannot be null or empty"); } if (readCapacity == null || readCapacity <= 0) { throw new IllegalArgumentException("Read capacity must be a positive number"); } try { LOGGER.info("Adding replica in region: " + replicaRegion.id() + " for table: " + tableName); // Create a ReplicationGroupUpdate for adding a replica ReplicationGroupUpdate replicationGroupUpdate = ReplicationGroupUpdate.builder() .create(builder -> builder.regionName(replicaRegion.id()) .globalSecondaryIndexes(ReplicaGlobalSecondaryIndex.builder() .indexName(indexName) .provisionedThroughputOverride(ProvisionedThroughputOverride.builder() .readCapacityUnits(readCapacity) .build()) .build()) .build()) .build(); UpdateTableRequest updateTableRequest = UpdateTableRequest.builder() .tableName(tableName) .replicaUpdates(replicationGroupUpdate) .build(); UpdateTableResponse response = dynamoDbClient.updateTable(updateTableRequest); LOGGER.info("Replica addition initiated in region: " + replicaRegion.id()); return response; } catch (DynamoDbException e) { LOGGER.severe("Failed to add replica in region: " + replicaRegion.id() + " - " + e.getMessage()); throw e; } }
Rimuovi una replica da una tabella globale utilizzando. AWS SDK for Java 2.x
public static UpdateTableResponse removeReplica( final DynamoDbClient dynamoDbClient, final String tableName, final Region replicaRegion) { if (dynamoDbClient == null) { throw new IllegalArgumentException("DynamoDB client cannot be null"); } if (tableName == null || tableName.trim().isEmpty()) { throw new IllegalArgumentException("Table name cannot be null or empty"); } if (replicaRegion == null) { throw new IllegalArgumentException("Replica region cannot be null"); } try { LOGGER.info("Removing replica in region: " + replicaRegion.id() + " for table: " + tableName); // Create a ReplicationGroupUpdate for removing a replica ReplicationGroupUpdate replicationGroupUpdate = ReplicationGroupUpdate.builder() .delete(builder -> builder.regionName(replicaRegion.id()).build()) .build(); UpdateTableRequest updateTableRequest = UpdateTableRequest.builder() .tableName(tableName) .replicaUpdates(replicationGroupUpdate) .build(); UpdateTableResponse response = dynamoDbClient.updateTable(updateTableRequest); LOGGER.info("Replica removal initiated in region: " + replicaRegion.id()); return response; } catch (DynamoDbException e) { LOGGER.severe("Failed to remove replica in region: " + replicaRegion.id() + " - " + e.getMessage()); throw e; } }
Aggiungi elementi di test per verificare la replica utilizzando. AWS SDK for Java 2.x
public static PutItemResponse putTestItem( final DynamoDbClient dynamoDbClient, final String tableName, final String artist, final String songTitle) { if (dynamoDbClient == null) { throw new IllegalArgumentException("DynamoDB client cannot be null"); } if (tableName == null || tableName.trim().isEmpty()) { throw new IllegalArgumentException("Table name cannot be null or empty"); } if (artist == null || artist.trim().isEmpty()) { throw new IllegalArgumentException("Artist cannot be null or empty"); } if (songTitle == null || songTitle.trim().isEmpty()) { throw new IllegalArgumentException("Song title cannot be null or empty"); } try { LOGGER.info("Adding test item to table: " + tableName); Map<String, software.amazon.awssdk.services.dynamodb.model.AttributeValue> item = new HashMap<>(); item.put( "Artist", software.amazon.awssdk.services.dynamodb.model.AttributeValue.builder() .s(artist) .build()); item.put( "SongTitle", software.amazon.awssdk.services.dynamodb.model.AttributeValue.builder() .s(songTitle) .build()); PutItemRequest putItemRequest = PutItemRequest.builder().tableName(tableName).item(item).build(); PutItemResponse response = dynamoDbClient.putItem(putItemRequest); LOGGER.info("Test item added successfully"); return response; } catch (DynamoDbException e) { LOGGER.severe("Failed to add test item to table: " + tableName + " - " + e.getMessage()); throw e; } }
Descrivi la configurazione globale della tabella e le repliche utilizzando. AWS SDK for Java 2.x
public static DescribeTableResponse describeTable(final DynamoDbClient dynamoDbClient, final String tableName) { if (dynamoDbClient == null) { throw new IllegalArgumentException("DynamoDB client cannot be null"); } if (tableName == null || tableName.trim().isEmpty()) { throw new IllegalArgumentException("Table name cannot be null or empty"); } try { LOGGER.info("Describing table: " + tableName); DescribeTableRequest request = DescribeTableRequest.builder().tableName(tableName).build(); DescribeTableResponse response = dynamoDbClient.describeTable(request); LOGGER.info("Table status: " + response.table().tableStatus()); if (response.table().replicas() != null && !response.table().replicas().isEmpty()) { LOGGER.info("Number of replicas: " + response.table().replicas().size()); response.table() .replicas() .forEach(replica -> LOGGER.info( "Replica region: " + replica.regionName() + ", Status: " + replica.replicaStatus())); } return response; } catch (ResourceNotFoundException e) { LOGGER.severe("Table not found: " + tableName + " - " + e.getMessage()); throw e; } catch (DynamoDbException e) { LOGGER.severe("Failed to describe table: " + tableName + " - " + e.getMessage()); throw e; } }
Esempio completo di operazioni su tabelle globali utilizzando AWS SDK for Java 2.x.
public static void exampleUsage(final Region sourceRegion, final Region replicaRegion) { String tableName = "Music"; String indexName = "SongTitleIndex"; Long readCapacity = 15L; // Create DynamoDB client for the source region try (DynamoDbClient dynamoDbClient = DynamoDbClient.builder().region(sourceRegion).build()) { try { // Step 1: Create the initial table with GSI and streams LOGGER.info("Step 1: Creating table in source region: " + sourceRegion.id()); createTableWithGSI(dynamoDbClient, tableName, indexName); // Step 2: Wait for table to become active LOGGER.info("Step 2: Waiting for table to become active"); waitForTableActive(dynamoDbClient, tableName); // Step 3: Add replica in destination region LOGGER.info("Step 3: Adding replica in region: " + replicaRegion.id()); addReplica(dynamoDbClient, tableName, replicaRegion, indexName, readCapacity); // Step 4: Wait a moment for replica creation to start Thread.sleep(5000); // Step 5: Describe table to view replica information LOGGER.info("Step 5: Describing table to view replicas"); describeTable(dynamoDbClient, tableName); // Step 6: Add a test item to verify replication LOGGER.info("Step 6: Adding test item to verify replication"); putTestItem(dynamoDbClient, tableName, "TestArtist", "TestSong"); LOGGER.info("Global table setup completed successfully!"); LOGGER.info("You can verify replication by checking the item in region: " + replicaRegion.id()); // Step 7: Remove replica and clean up table LOGGER.info("Step 7: Removing replica from region: " + replicaRegion.id()); removeReplica(dynamoDbClient, tableName, replicaRegion); DeleteTableResponse deleteTableResponse = dynamoDbClient.deleteTable( DeleteTableRequest.builder().tableName(tableName).build()); LOGGER.info("MREC global table demonstration completed successfully!"); } catch (InterruptedException e) { Thread.currentThread().interrupt(); throw new RuntimeException("Thread was interrupted", e); } catch (DynamoDbException e) { LOGGER.severe("DynamoDB operation failed: " + e.getMessage()); throw e; } } }
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Per informazioni dettagliate sull'API, consulta i seguenti argomenti nella Documentazione di riferimento delle API AWS SDK for Java 2.x .
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Per un elenco completo delle guide per sviluppatori AWS SDK e degli esempi di codice, consultaUtilizzo di DynamoDB con un SDK AWS. Questo argomento include anche informazioni su come iniziare e dettagli sulle versioni precedenti dell'SDK.