Perubahan dalam APIs pemetaan/dokumen DynamoDB dari versi 1 ke versi 2

<dependencyManagement>
  <dependencies>
    <dependency>
      <groupId>com.amazonaws</groupId>
      <artifactId>aws-java-sdk-bom</artifactId>
      <version>1.X.X</version>
      <type>pom</type>
      <scope>import</scope>
    </dependency>
  </dependencies>
</dependencyManagement> 

<dependencies>
  <dependency>
    <groupId>com.amazonaws</groupId>
    <artifactId>aws-java-sdk-dynamodb</artifactId>
  </dependency>
</dependencies>

<dependencyManagement>
  <dependencies>
    <dependency>
      <groupId>software.amazon.awssdk</groupId>
      <artifactId>bom</artifactId>
      <version>2.X.X*</version>
      <type>pom</type>
      <scope>import</scope>
    </dependency>
  </dependencies>
</dependencyManagement> 

<dependencies>
  <dependency>
    <groupId>software.amazon.awssdk</groupId>
    <artifactId>dynamodb-enhanced</artifactId>
  </dependency>
</dependencies>

Instantiasi normal

AmazonDynamoDB standardClient = AmazonDynamoDBClientBuilder.standard()
    .withCredentials(credentialsProvider)
    .withRegion(Regions.US_EAST_1)
    .build();
DynamoDBMapper mapper = new DynamoDBMapper(standardClient);

DynamoDbClient standardClient = DynamoDbClient.builder()
    .credentialsProvider(ProfileCredentialsProvider.create())
    .region(Region.US_EAST_1)
    .build();
DynamoDbEnhancedClient enhancedClient = DynamoDbEnhancedClient.builder()
    .dynamoDbClient(standardClient)
    .build();

Instantiasi minimal

AmazonDynamoDB standardClient = AmazonDynamoDBClientBuilder.standard();
DynamoDBMapper mapper = new DynamoDBMapper(standardClient);

DynamoDbEnhancedClient enhancedClient = DynamoDbEnhancedClient.create();

Dengan trafo ^atribut*

DynamoDBMapper mapper = new DynamoDBMapper(standardClient, 
                        attributeTransformerInstance);

DynamoDbEnhancedClient enhancedClient = DynamoDbEnhancedClient.builder()
    .dynamoDbClient(standardClient)
    .extensions(extensionAInstance, extensionBInstance)
    .build();

Memetakan POJO kelas Java ke tabel DynamoDB

@DynamoDBTable(tableName ="Customer")
public class Customer {
  ...
}

DynamoDbTable<Customer> customerTable = enhancedClient.table("Customer",
    TableSchema.fromBean(Customer.class));

Peta ke indeks sekunder DynamoDB

Bagian dalam DynamoDB Developer Guide yang membahas metode query v1 menunjukkan contoh lengkap.

Gunakan indeks sekunderBagian dalam panduan ini memberikan informasi lebih lanjut.

Menulis Java POJO ke tabel DynamoDB

mapper.save(item)
mapper.save(item, config)
mapper.save(item, saveExpression, config)

Dalam v1, DynamoDBMapperConfig.SaveBehavior dan anotasi menentukan metode DynamoDB tingkat rendah mana yang akan dipanggil. Secara umum, UpdateItem disebut kecuali saat menggunakan SaveBehavior.CLOBBER danSaveBehavior.PUT. Kunci yang dihasilkan secara otomatis adalah kasus penggunaan khusus, dan kadang-kadang keduanya PutItem dan UpdateItem digunakan.

table.putItem(putItemRequest)
table.putItem(item)
table.putItemWithResponse(item) //Returns metadata.

updateItem(updateItemRequest)
table.updateItem(item)
table.updateItemWithResponse(item) //Returns metadata.

mapper.load(item)
mapper.load(item, config)

table.getItem(getItemRequest)
table.getItem(item)
table.getItem(key)
table.getItemWithResponse(key) //Returns POJO with metadata.

mapper.delete(item, deleteExpression, config)

table.deleteItem(deleteItemRequest)
table.deleteItem(item)
table.deleteItem(key)

mapper.query(Customer.class, queryExpression)
mapper.query(Customer.class, queryExpression, mapperConfig)

table.query(queryRequest)
table.query(queryConditional)

Gunakan yang dikembalikan PageIterable.stream() (pemuatan lambat) untuk respons sinkronisasi dan PagePublisher.subscribe() untuk respons asinkron

mapper.queryPage(Customer.class, queryExpression)
mapper.queryPage(Customer.class, queryExpression, mapperConfig)

table.query(queryRequest)
table.query(queryConditional)

Gunakan yang dikembalikan PageIterable.items() (pemuatan lambat) untuk respons sinkronisasi dan PagePublisher.items.subscribe() untuk respons asinkron

mapper.scan(Customer.class, scanExpression)
mapper.scan(Customer.class, scanExpression, mapperConfig)

table.scan()
table.scan(scanRequest)

Gunakan yang dikembalikan PageIterable.stream() (pemuatan lambat) untuk respons sinkronisasi dan PagePublisher.subscribe() untuk respons asinkron

mapper.scanPage(Customer.class, scanExpression)
mapper.scanPage(Customer.class, scanExpression, mapperConfig)

table.scan()
table.scan(scanRequest)

Gunakan yang dikembalikan PageIterable.items() (pemuatan lambat) untuk respons sinkronisasi dan PagePublisher.items.subscribe() untuk respons asinkron

mapper.batchLoad(Arrays.asList(customer1, customer2, book1))
mapper.batchLoad(itemsToGet) // itemsToGet: Map<Class<?>, List<KeyPair>>

enhancedClient.batchGetItem(batchGetItemRequest)

enhancedClient.batchGetItem(r -> r.readBatches(
    ReadBatch.builder(Record1.class)
             .mappedTableResource(mappedTable1)
             .addGetItem(i -> i.key(k -> k.partitionValue(0)))
             .build(),
    ReadBatch.builder(Record2.class)
             .mappedTableResource(mappedTable2)
             .addGetItem(i -> i.key(k -> k.partitionValue(0)))
             .build()))

// Iterate over pages with lazy loading or over all items from the same table.

mapper.batchSave(Arrays.asList(customer1, customer2, book1)) 

enhancedClient.batchWriteItem(batchWriteItemRequest)

enhancedClient.batchWriteItem(r -> r.writeBatches(
    WriteBatch.builder(Record1.class)
             .mappedTableResource(mappedTable1)
             .addPutItem(item1)
             .build(),
    WriteBatch.builder(Record2.class)
             .mappedTableResource(mappedTable2)
             .addPutItem(item2)
             .build()))

mapper.batchDelete(Arrays.asList(customer1, customer2, book1)) 

enhancedClient.batchWriteItem(r -> r.writeBatches(
    WriteBatch.builder(Record1.class)
             .mappedTableResource(mappedTable1)
             .addDeleteItem(item1key)
             .build(),
    WriteBatch.builder(Record2.class)
             .mappedTableResource(mappedTable2)
             .addDeleteItem(item2key)
             .build()))

mapper.batchWrite(Arrays.asList(customer1, book1), Arrays.asList(customer2)) 

enhancedClient.batchWriteItem(r -> r.writeBatches(
    WriteBatch.builder(Record1.class)
             .mappedTableResource(mappedTable1)
             .addPutItem(item1)
             .build(),
    WriteBatch.builder(Record2.class)
             .mappedTableResource(mappedTable2)
             .addDeleteItem(item2key)
             .build()))

mapper.transactionWrite(transactionWriteRequest)

enhancedClient.transactWriteItems(transasctWriteItemsRequest)

mapper.transactionLoad(transactionLoadRequest)

enhancedClient.transactGetItems(transactGetItemsRequest) 

mapper.count(Customer.class, queryExpression)
mapper.count(Customer.class, scanExpression)

mapper.generateCreateTableRequest(Customer.class)

Pernyataan sebelumnya menghasilkan permintaan tabel buat tingkat rendah; pengguna harus memanggil klien createTable DynamoDB.

table.createTable(createTableRequest)

table.createTable(r -> r.provisionedThroughput(getDefaultProvisionedThroughput())
        .globalSecondaryIndices(
                EnhancedGlobalSecondaryIndex.builder()
                        .indexName("gsi_1")
                        .projection(p -> p.projectionType(ProjectionType.ALL))
                        .provisionedThroughput(getDefaultProvisionedThroughput())
                        .build()));

mapper.parallelScan(Customer.class, scanExpression, numTotalSegments)

Pengguna diminta untuk menangani thread pekerja dan memanggil scan untuk setiap segmen:

table.scan(r -> r.segment(0).totalSegments(5))

mapper.createS3Link(bucket, key)
mapper.getS3ClientCache()

Tidak didukung karena memasangkan Amazon S3 dan DynamoDB.

@DynamoDBTable (tableName ="CustomerTable")

@DynamoDbBean
@DynamoDbBean(converterProviders = {...})

@DynamoDBAttribute(attributeName = "customerName")

@DynamoDbAttribute("customerName") 

@DynamoDBHashKey 

@DynamoDbPartitionKey

@DynamoDBHashKey 

@DynamoDbSortKey 

@DynamoDBIndexHashKey 

@DynamoDbSecondaryPartitionKey 

@DynamoDBIndexRangeKey 

@DynamoDbSecondarySortKey 

@DynamoDBIgnore 

@DynamoDbIgnore

@DynamoDBAutoGeneratedKey

@DynamoDbAutoGeneratedUuid 

Ekstensi yang menyediakan ini tidak dimuat secara default; Anda harus menambahkan ekstensi ke pembuat klien.

@DynamoDBAutoGeneratedTimestamp

@DynamoDbAutoGeneratedTimestampAttribute

Ekstensi yang menyediakan ini tidak dimuat secara default; Anda harus menambahkan ekstensi ke pembuat klien.

@DynamoDBVersionAttribute

@DynamoDbVersionAttribute

Ekstensi yang menyediakan ini dimuat secara otomatis.

@DynamoDBTypeConverted

@DynamoDbConvertedBy

@DynamoDBTyped(<DynamoDBAttributeType>)

@DynamoDBDocument

@DynamoDbIgnoreNulls

@DynamoDbPreserveEmptyObject

@DynamoDbUpdateBehavior

@DynamoDbImmutable

@DynamoDbAtomicCounter

Ekstensi yang menyediakan fungsi ini dimuat secara otomatis.

DynamoDBMapperConfig.builder()

  .withBatchLoadRetryStrategy(batchLoadRetryStrategy)

  .withBatchWriteRetryStrategy(batchWriteRetryStrategy)

  .withConsistentReads(CONSISTENT)

  .withConversionSchema(conversionSchema)

Implementasi statis memberikan kompatibilitas mundur dengan versi yang lebih lama.

  .withObjectTableNameResolver()
  .withTableNameOverride() 
  .withTableNameResolver()

Implementasi statis memberikan kompatibilitas mundur dengan versi yang lebih lama

Nama tabel didefinisikan saat memanggil DynamoDbEDnhancedClient#table() metode.

  .withPaginationLoadingStrategy(strategy)

Pilihannya adalah: LAZY _LOADING,EAGER_LOADING, atau ITERATION_ONLY

Iterasi saja adalah default. Opsi v1 lainnya tidak didukung.

  .withRequestMetricCollector(collector)

  .withSaveBehavior(SaveBehavior.CLOBBER) 

Pilihannya adalah UPDATECLOBBER,,PUT,APPEND_SET, atauUPDATE_SKIP_NULL_ATTRIBUTES.

Di v2, Anda menelepon putItem() atau updateItem() secara eksplisit.

CLOBBER or PUT: Tindakan yang sesuai di v 2 memanggilputItem(). Tidak ada CLOBBER konfigurasi khusus.

UPDATE: Sesuai dengan updateItem()

UPDATE_SKIP_NULL_ATTRIBUTES: Sesuai denganupdateItem(). Kontrol perilaku pembaruan dengan setelan permintaan ignoreNulls dan anotasi/tagDynamoDbUpdateBehavior.

APPEND_SET: Tidak didukung

  .withTypeConverterFactory(typeConverterFactory) 

Atur kacang dengan menggunakan

@DynamoDbBean(converterProviders = {ConverterProvider.class, 
        DefaultAttributeConverterProvider.class})

new DynamoDBSaveExpression()
  .withExpected(Collections.singletonMap(
      "otherAttribute", new ExpectedAttributeValue(false)))
  .withConditionalOperator(ConditionalOperator.AND);

deleteExpression.setConditionExpression("zipcode = :zipcode")
deleteExpression.setExpressionAttributeValues(...)

Expression conditionExpression =
    Expression.builder()
        .expression("#key = :value OR #key1 = :value1")
        .putExpressionName("#key", "attribute")
        .putExpressionName("#key1", "attribute3")
        .putExpressionValue(":value", AttributeValues.stringValue("wrong"))
        .putExpressionValue(":value1", AttributeValues.stringValue("three"))
        .build();

DeleteItemEnhancedRequest request = DeleteItemEnhancedRequest.builder()
         .conditionExpression(conditionExpression).build();

scanExpression
  .withFilterExpression("#statename = :state")
  .withExpressionAttributeValues(attributeValueMapBuilder.build())
  .withExpressionAttributeNames(attributeNameMapBuilder.build())

Map<String, AttributeValue> values = singletonMap(":key", stringValue("value"));
Expression filterExpression =
    Expression.builder()
        .expression("name = :key")
        .expressionValues(values)
        .build();
QueryEnhancedRequest request = QueryEnhancedRequest.builder()
    .filterExpression(filterExpression).build();

queryExpression.withKeyConditionExpression()

QueryConditional keyEqual = QueryConditional.keyEqualTo(b -> b
                .partitionValue("movie01"));

QueryEnhancedRequest tableQuery = QueryEnhancedRequest.builder()
                .queryConditional(keyEqual)
                .build();

AmazonDynamoDB client = ... //Create a client.
DynamoDB documentClient = new DynamoDB(client);

// The v2 Document API uses the same DynamoDbEnhancedClient
// that is used for mapping POJOs.
DynamoDbClient standardClient = ... //Create a standard client.
DynamoDbEnhancedClient enhancedClient = ... // Create an enhanced client.

Table documentTable = docClient.documentClient("Person");

DynamoDbTable<EnhancedDocument> documentTable = enhancedClient.table("Person",  
        TableSchema.documentSchemaBuilder()
              .addIndexPartitionKey(TableMetadata.primaryIndexName(),"id", AttributeValueType.S)
              .attributeConverterProviders(AttributeConverterProvider.defaultProvider())
              .build());

Item item = new Item()
      .withPrimaryKey("id", 50)
      .withString("firstName", "Shirley");
PutItemOutcome outcome = documentTable.putItem(item);

EnhancedDocument personDocument = EnhancedDocument.builder()
        .putNumber("id", 50)
        .putString("firstName", "Shirley")
        .build();
documentTable.putItem(personDocument);

GetItemOutcome outcome = documentTable.getItemOutcome( "id", 50);
Item personDocFromDb = outcome.getItem();
String firstName = personDocFromDb.getString("firstName");

EnhancedDocument personDocFromDb = documentTable
        .getItem(Key.builder()
            .partitionValue(50)
            .build()); 
String firstName = personDocFromDb.getString("firstName");

// The 'jsonPerson' identifier is a JSON string. 
Item item = new Item().fromJSON(jsonPerson);

// The 'jsonPerson' identifier is a JSON string.
EnhancedDocument document = EnhancedDocument.builder()
        .json(jsonPerson).build());

documentTable.putItem(item)

documentTable.putItem(document);

GetItemOutcome outcome = //Get item.
String jsonPerson = outcome.getItem().toJSON();

String jsonPerson = documentTable.getItem(Key.builder()
        .partitionValue(50).build())
        .fromJson();