用于 Kotlin 的 Amazon Keysp SDK aces 示例 - AWS SDK代码示例

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用于 Kotlin 的 Amazon Keysp SDK aces 示例

以下代码示例向您展示了如何使用 for Kotlin 和 Amazon Keyspaces 来执行操作和实现常见场景。 AWS SDK

基础知识是向您展示如何在服务中执行基本操作的代码示例。

操作是大型程序的代码摘录,必须在上下文中运行。您可以通过操作了解如何调用单个服务函数,还可以通过函数相关场景的上下文查看操作。

每个示例都包含一个指向完整源代码的链接,您可以在其中找到有关如何在上下文中设置和运行代码的说明。

开始使用

以下代码示例展示了如何开始使用 Amazon Keyspaces。

SDK对于 Kotlin 来说
注意

还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库中进行设置和运行。

/** Before running this Kotlin code example, set up your development environment, including your credentials. For more information, see the following documentation topic: https://docs.aws.amazon.com/sdk-for-kotlin/latest/developer-guide/setup.html */ suspend fun main() { listKeyspaces() } suspend fun listKeyspaces() { val keyspacesRequest = ListKeyspacesRequest { maxResults = 10 } KeyspacesClient { region = "us-east-1" }.use { keyClient -> val response = keyClient.listKeyspaces(keyspacesRequest) response.keyspaces?.forEach { keyspace -> println("The name of the keyspace is ${keyspace.keyspaceName}") } } }
  • 有关API详细信息,请参阅ListKeyspaces中的 Kotlin AWS SDK API 参考

基础知识

以下代码示例展示了如何:

  • 创建密钥空间和表。表架构保存电影数据并启用了 point-in-time恢复。

  • 使用带有 Sigv4 身份验证的安全TLS连接连接到密钥空间。

  • 查询表。添加、检索和更新电影数据。

  • 更新表。添加一列来跟踪观看的电影。

  • 将表还原到以前的状态并清理资源。

SDK对于 Kotlin 来说
注意

还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库中进行设置和运行。

/** Before running this Kotlin code example, set up your development environment, including your credentials. For more information, see the following documentation topic: https://docs.aws.amazon.com/sdk-for-kotlin/latest/developer-guide/setup.html This example uses a secure file format to hold certificate information for Kotlin applications. This is required to make a connection to Amazon Keyspaces. For more information, see the following documentation topic: https://docs.aws.amazon.com/keyspaces/latest/devguide/using_java_driver.html This Kotlin example performs the following tasks: 1. Create a keyspace. 2. Check for keyspace existence. 3. List keyspaces using a paginator. 4. Create a table with a simple movie data schema and enable point-in-time recovery. 5. Check for the table to be in an Active state. 6. List all tables in the keyspace. 7. Use a Cassandra driver to insert some records into the Movie table. 8. Get all records from the Movie table. 9. Get a specific Movie. 10. Get a UTC timestamp for the current time. 11. Update the table schema to add a ‘watched’ Boolean column. 12. Update an item as watched. 13. Query for items with watched = True. 14. Restore the table back to the previous state using the timestamp. 15. Check for completion of the restore action. 16. Delete the table. 17. Confirm that both tables are deleted. 18. Delete the keyspace. */ /* Usage: fileName - The name of the JSON file that contains movie data. (Get this file from the GitHub repo at resources/sample_file.) keyspaceName - The name of the keyspace to create. */ val DASHES: String = String(CharArray(80)).replace("\u0000", "-") suspend fun main() { val fileName = "<Replace with the JSON file that contains movie data>" val keyspaceName = "<Replace with the name of the keyspace to create>" val titleUpdate = "The Family" val yearUpdate = 2013 val tableName = "MovieKotlin" val tableNameRestore = "MovieRestore" val loader = DriverConfigLoader.fromClasspath("application.conf") val session = CqlSession .builder() .withConfigLoader(loader) .build() println(DASHES) println("Welcome to the Amazon Keyspaces example scenario.") println(DASHES) println(DASHES) println("1. Create a keyspace.") createKeySpace(keyspaceName) println(DASHES) println(DASHES) delay(5000) println("2. Check for keyspace existence.") checkKeyspaceExistence(keyspaceName) println(DASHES) println(DASHES) println("3. List keyspaces using a paginator.") listKeyspacesPaginator() println(DASHES) println(DASHES) println("4. Create a table with a simple movie data schema and enable point-in-time recovery.") createTable(keyspaceName, tableName) println(DASHES) println(DASHES) println("5. Check for the table to be in an Active state.") delay(6000) checkTable(keyspaceName, tableName) println(DASHES) println(DASHES) println("6. List all tables in the keyspace.") listTables(keyspaceName) println(DASHES) println(DASHES) println("7. Use a Cassandra driver to insert some records into the Movie table.") delay(6000) loadData(session, fileName, keyspaceName) println(DASHES) println(DASHES) println("8. Get all records from the Movie table.") getMovieData(session, keyspaceName) println(DASHES) println(DASHES) println("9. Get a specific Movie.") getSpecificMovie(session, keyspaceName) println(DASHES) println(DASHES) println("10. Get a UTC timestamp for the current time.") val utc = ZonedDateTime.now(ZoneOffset.UTC) println("DATETIME = ${Date.from(utc.toInstant())}") println(DASHES) println(DASHES) println("11. Update the table schema to add a watched Boolean column.") updateTable(keyspaceName, tableName) println(DASHES) println(DASHES) println("12. Update an item as watched.") delay(10000) // Wait 10 seconds for the update. updateRecord(session, keyspaceName, titleUpdate, yearUpdate) println(DASHES) println(DASHES) println("13. Query for items with watched = True.") getWatchedData(session, keyspaceName) println(DASHES) println(DASHES) println("14. Restore the table back to the previous state using the timestamp.") println("Note that the restore operation can take up to 20 minutes.") restoreTable(keyspaceName, utc) println(DASHES) println(DASHES) println("15. Check for completion of the restore action.") delay(5000) checkRestoredTable(keyspaceName, "MovieRestore") println(DASHES) println(DASHES) println("16. Delete both tables.") deleteTable(keyspaceName, tableName) deleteTable(keyspaceName, tableNameRestore) println(DASHES) println(DASHES) println("17. Confirm that both tables are deleted.") checkTableDelete(keyspaceName, tableName) checkTableDelete(keyspaceName, tableNameRestore) println(DASHES) println(DASHES) println("18. Delete the keyspace.") deleteKeyspace(keyspaceName) println(DASHES) println(DASHES) println("The scenario has completed successfully.") println(DASHES) } suspend fun deleteKeyspace(keyspaceNameVal: String?) { val deleteKeyspaceRequest = DeleteKeyspaceRequest { keyspaceName = keyspaceNameVal } KeyspacesClient { region = "us-east-1" }.use { keyClient -> keyClient.deleteKeyspace(deleteKeyspaceRequest) } } suspend fun checkTableDelete( keyspaceNameVal: String?, tableNameVal: String?, ) { var status: String var response: GetTableResponse val tableRequest = GetTableRequest { keyspaceName = keyspaceNameVal tableName = tableNameVal } try { KeyspacesClient { region = "us-east-1" }.use { keyClient -> // Keep looping until the table cannot be found and a ResourceNotFoundException is thrown. while (true) { response = keyClient.getTable(tableRequest) status = response.status.toString() println(". The table status is $status") delay(500) } } } catch (e: ResourceNotFoundException) { println(e.message) } println("The table is deleted") } suspend fun deleteTable( keyspaceNameVal: String?, tableNameVal: String?, ) { val tableRequest = DeleteTableRequest { keyspaceName = keyspaceNameVal tableName = tableNameVal } KeyspacesClient { region = "us-east-1" }.use { keyClient -> keyClient.deleteTable(tableRequest) } } suspend fun checkRestoredTable( keyspaceNameVal: String?, tableNameVal: String?, ) { var tableStatus = false var status: String var response: GetTableResponse? = null val tableRequest = GetTableRequest { keyspaceName = keyspaceNameVal tableName = tableNameVal } KeyspacesClient { region = "us-east-1" }.use { keyClient -> while (!tableStatus) { response = keyClient.getTable(tableRequest) status = response!!.status.toString() println("The table status is $status") if (status.compareTo("ACTIVE") == 0) { tableStatus = true } delay(500) } val cols = response!!.schemaDefinition?.allColumns if (cols != null) { for (def in cols) { println("The column name is ${def.name}") println("The column type is ${def.type}") } } } } suspend fun restoreTable( keyspaceName: String?, utc: ZonedDateTime, ) { // Create an aws.smithy.kotlin.runtime.time.Instant value. val timeStamp = aws.smithy.kotlin.runtime.time .Instant(utc.toInstant()) val restoreTableRequest = RestoreTableRequest { restoreTimestamp = timeStamp sourceTableName = "MovieKotlin" targetKeyspaceName = keyspaceName targetTableName = "MovieRestore" sourceKeyspaceName = keyspaceName } KeyspacesClient { region = "us-east-1" }.use { keyClient -> val response = keyClient.restoreTable(restoreTableRequest) println("The ARN of the restored table is ${response.restoredTableArn}") } } fun getWatchedData( session: CqlSession, keyspaceName: String, ) { val resultSet = session.execute("SELECT * FROM \"$keyspaceName\".\"MovieKotlin\" WHERE watched = true ALLOW FILTERING;") resultSet.forEach { item: Row -> println("The Movie title is ${item.getString("title")}") println("The Movie year is ${item.getInt("year")}") println("The plot is ${item.getString("plot")}") } } fun updateRecord( session: CqlSession, keySpace: String, titleUpdate: String?, yearUpdate: Int, ) { val sqlStatement = "UPDATE \"$keySpace\".\"MovieKotlin\" SET watched=true WHERE title = :k0 AND year = :k1;" val builder = BatchStatement.builder(DefaultBatchType.UNLOGGED) builder.setConsistencyLevel(ConsistencyLevel.LOCAL_QUORUM) val preparedStatement = session.prepare(sqlStatement) builder.addStatement( preparedStatement .boundStatementBuilder() .setString("k0", titleUpdate) .setInt("k1", yearUpdate) .build(), ) val batchStatement = builder.build() session.execute(batchStatement) } suspend fun updateTable( keySpace: String?, tableNameVal: String?, ) { val def = ColumnDefinition { name = "watched" type = "boolean" } val tableRequest = UpdateTableRequest { keyspaceName = keySpace tableName = tableNameVal addColumns = listOf(def) } KeyspacesClient { region = "us-east-1" }.use { keyClient -> keyClient.updateTable(tableRequest) } } fun getSpecificMovie( session: CqlSession, keyspaceName: String, ) { val resultSet = session.execute("SELECT * FROM \"$keyspaceName\".\"MovieKotlin\" WHERE title = 'The Family' ALLOW FILTERING ;") resultSet.forEach { item: Row -> println("The Movie title is ${item.getString("title")}") println("The Movie year is ${item.getInt("year")}") println("The plot is ${item.getString("plot")}") } } // Get records from the Movie table. fun getMovieData( session: CqlSession, keyspaceName: String, ) { val resultSet = session.execute("SELECT * FROM \"$keyspaceName\".\"MovieKotlin\";") resultSet.forEach { item: Row -> println("The Movie title is ${item.getString("title")}") println("The Movie year is ${item.getInt("year")}") println("The plot is ${item.getString("plot")}") } } // Load data into the table. fun loadData( session: CqlSession, fileName: String, keySpace: String, ) { val sqlStatement = "INSERT INTO \"$keySpace\".\"MovieKotlin\" (title, year, plot) values (:k0, :k1, :k2)" val parser = JsonFactory().createParser(File(fileName)) val rootNode = ObjectMapper().readTree<JsonNode>(parser) val iter: Iterator<JsonNode> = rootNode.iterator() var currentNode: ObjectNode var t = 0 while (iter.hasNext()) { if (t == 50) { break } currentNode = iter.next() as ObjectNode val year = currentNode.path("year").asInt() val title = currentNode.path("title").asText() val info = currentNode.path("info").toString() // Insert the data into the Amazon Keyspaces table. val builder = BatchStatement.builder(DefaultBatchType.UNLOGGED) builder.setConsistencyLevel(ConsistencyLevel.LOCAL_QUORUM) val preparedStatement: PreparedStatement = session.prepare(sqlStatement) builder.addStatement( preparedStatement .boundStatementBuilder() .setString("k0", title) .setInt("k1", year) .setString("k2", info) .build(), ) val batchStatement = builder.build() session.execute(batchStatement) t++ } } suspend fun listTables(keyspaceNameVal: String?) { val tablesRequest = ListTablesRequest { keyspaceName = keyspaceNameVal } KeyspacesClient { region = "us-east-1" }.use { keyClient -> keyClient .listTablesPaginated(tablesRequest) .transform { it.tables?.forEach { obj -> emit(obj) } } .collect { obj -> println(" ARN: ${obj.resourceArn} Table name: ${obj.tableName}") } } } suspend fun checkTable( keyspaceNameVal: String?, tableNameVal: String?, ) { var tableStatus = false var status: String var response: GetTableResponse? = null val tableRequest = GetTableRequest { keyspaceName = keyspaceNameVal tableName = tableNameVal } KeyspacesClient { region = "us-east-1" }.use { keyClient -> while (!tableStatus) { response = keyClient.getTable(tableRequest) status = response!!.status.toString() println(". The table status is $status") if (status.compareTo("ACTIVE") == 0) { tableStatus = true } delay(500) } val cols: List<ColumnDefinition>? = response!!.schemaDefinition?.allColumns if (cols != null) { for (def in cols) { println("The column name is ${def.name}") println("The column type is ${def.type}") } } } } suspend fun createTable( keySpaceVal: String?, tableNameVal: String?, ) { // Set the columns. val defTitle = ColumnDefinition { name = "title" type = "text" } val defYear = ColumnDefinition { name = "year" type = "int" } val defReleaseDate = ColumnDefinition { name = "release_date" type = "timestamp" } val defPlot = ColumnDefinition { name = "plot" type = "text" } val colList = ArrayList<ColumnDefinition>() colList.add(defTitle) colList.add(defYear) colList.add(defReleaseDate) colList.add(defPlot) // Set the keys. val yearKey = PartitionKey { name = "year" } val titleKey = PartitionKey { name = "title" } val keyList = ArrayList<PartitionKey>() keyList.add(yearKey) keyList.add(titleKey) val schemaDefinitionOb = SchemaDefinition { partitionKeys = keyList allColumns = colList } val timeRecovery = PointInTimeRecovery { status = PointInTimeRecoveryStatus.Enabled } val tableRequest = CreateTableRequest { keyspaceName = keySpaceVal tableName = tableNameVal schemaDefinition = schemaDefinitionOb pointInTimeRecovery = timeRecovery } KeyspacesClient { region = "us-east-1" }.use { keyClient -> val response = keyClient.createTable(tableRequest) println("The table ARN is ${response.resourceArn}") } } suspend fun listKeyspacesPaginator() { KeyspacesClient { region = "us-east-1" }.use { keyClient -> keyClient .listKeyspacesPaginated(ListKeyspacesRequest {}) .transform { it.keyspaces?.forEach { obj -> emit(obj) } } .collect { obj -> println("Name: ${obj.keyspaceName}") } } } suspend fun checkKeyspaceExistence(keyspaceNameVal: String?) { val keyspaceRequest = GetKeyspaceRequest { keyspaceName = keyspaceNameVal } KeyspacesClient { region = "us-east-1" }.use { keyClient -> val response: GetKeyspaceResponse = keyClient.getKeyspace(keyspaceRequest) val name = response.keyspaceName println("The $name KeySpace is ready") } } suspend fun createKeySpace(keyspaceNameVal: String) { val keyspaceRequest = CreateKeyspaceRequest { keyspaceName = keyspaceNameVal } KeyspacesClient { region = "us-east-1" }.use { keyClient -> val response = keyClient.createKeyspace(keyspaceRequest) println("The ARN of the KeySpace is ${response.resourceArn}") } }

操作

以下代码示例演示如何使用 CreateKeyspace

SDK对于 Kotlin 来说
注意

还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库中进行设置和运行。

suspend fun createKeySpace(keyspaceNameVal: String) { val keyspaceRequest = CreateKeyspaceRequest { keyspaceName = keyspaceNameVal } KeyspacesClient { region = "us-east-1" }.use { keyClient -> val response = keyClient.createKeyspace(keyspaceRequest) println("The ARN of the KeySpace is ${response.resourceArn}") } }
  • 有关API详细信息,请参阅CreateKeyspace中的 Kotlin AWS SDK API 参考

以下代码示例演示如何使用 CreateTable

SDK对于 Kotlin 来说
注意

还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库中进行设置和运行。

suspend fun createTable( keySpaceVal: String?, tableNameVal: String?, ) { // Set the columns. val defTitle = ColumnDefinition { name = "title" type = "text" } val defYear = ColumnDefinition { name = "year" type = "int" } val defReleaseDate = ColumnDefinition { name = "release_date" type = "timestamp" } val defPlot = ColumnDefinition { name = "plot" type = "text" } val colList = ArrayList<ColumnDefinition>() colList.add(defTitle) colList.add(defYear) colList.add(defReleaseDate) colList.add(defPlot) // Set the keys. val yearKey = PartitionKey { name = "year" } val titleKey = PartitionKey { name = "title" } val keyList = ArrayList<PartitionKey>() keyList.add(yearKey) keyList.add(titleKey) val schemaDefinitionOb = SchemaDefinition { partitionKeys = keyList allColumns = colList } val timeRecovery = PointInTimeRecovery { status = PointInTimeRecoveryStatus.Enabled } val tableRequest = CreateTableRequest { keyspaceName = keySpaceVal tableName = tableNameVal schemaDefinition = schemaDefinitionOb pointInTimeRecovery = timeRecovery } KeyspacesClient { region = "us-east-1" }.use { keyClient -> val response = keyClient.createTable(tableRequest) println("The table ARN is ${response.resourceArn}") } }
  • 有关API详细信息,请参阅CreateTable中的 Kotlin AWS SDK API 参考

以下代码示例演示如何使用 DeleteKeyspace

SDK对于 Kotlin 来说
注意

还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库中进行设置和运行。

suspend fun deleteKeyspace(keyspaceNameVal: String?) { val deleteKeyspaceRequest = DeleteKeyspaceRequest { keyspaceName = keyspaceNameVal } KeyspacesClient { region = "us-east-1" }.use { keyClient -> keyClient.deleteKeyspace(deleteKeyspaceRequest) } }
  • 有关API详细信息,请参阅DeleteKeyspace中的 Kotlin AWS SDK API 参考

以下代码示例演示如何使用 DeleteTable

SDK对于 Kotlin 来说
注意

还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库中进行设置和运行。

suspend fun deleteTable( keyspaceNameVal: String?, tableNameVal: String?, ) { val tableRequest = DeleteTableRequest { keyspaceName = keyspaceNameVal tableName = tableNameVal } KeyspacesClient { region = "us-east-1" }.use { keyClient -> keyClient.deleteTable(tableRequest) } }
  • 有关API详细信息,请参阅DeleteTable中的 Kotlin AWS SDK API 参考

以下代码示例演示如何使用 GetKeyspace

SDK对于 Kotlin 来说
注意

还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库中进行设置和运行。

suspend fun checkKeyspaceExistence(keyspaceNameVal: String?) { val keyspaceRequest = GetKeyspaceRequest { keyspaceName = keyspaceNameVal } KeyspacesClient { region = "us-east-1" }.use { keyClient -> val response: GetKeyspaceResponse = keyClient.getKeyspace(keyspaceRequest) val name = response.keyspaceName println("The $name KeySpace is ready") } }
  • 有关API详细信息,请参阅GetKeyspace中的 Kotlin AWS SDK API 参考

以下代码示例演示如何使用 GetTable

SDK对于 Kotlin 来说
注意

还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库中进行设置和运行。

suspend fun checkTable( keyspaceNameVal: String?, tableNameVal: String?, ) { var tableStatus = false var status: String var response: GetTableResponse? = null val tableRequest = GetTableRequest { keyspaceName = keyspaceNameVal tableName = tableNameVal } KeyspacesClient { region = "us-east-1" }.use { keyClient -> while (!tableStatus) { response = keyClient.getTable(tableRequest) status = response!!.status.toString() println(". The table status is $status") if (status.compareTo("ACTIVE") == 0) { tableStatus = true } delay(500) } val cols: List<ColumnDefinition>? = response!!.schemaDefinition?.allColumns if (cols != null) { for (def in cols) { println("The column name is ${def.name}") println("The column type is ${def.type}") } } } }
  • 有关API详细信息,请参阅GetTable中的 Kotlin AWS SDK API 参考

以下代码示例演示如何使用 ListKeyspaces

SDK对于 Kotlin 来说
注意

还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库中进行设置和运行。

suspend fun listKeyspacesPaginator() { KeyspacesClient { region = "us-east-1" }.use { keyClient -> keyClient .listKeyspacesPaginated(ListKeyspacesRequest {}) .transform { it.keyspaces?.forEach { obj -> emit(obj) } } .collect { obj -> println("Name: ${obj.keyspaceName}") } } }
  • 有关API详细信息,请参阅ListKeyspaces中的 Kotlin AWS SDK API 参考

以下代码示例演示如何使用 ListTables

SDK对于 Kotlin 来说
注意

还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库中进行设置和运行。

suspend fun listTables(keyspaceNameVal: String?) { val tablesRequest = ListTablesRequest { keyspaceName = keyspaceNameVal } KeyspacesClient { region = "us-east-1" }.use { keyClient -> keyClient .listTablesPaginated(tablesRequest) .transform { it.tables?.forEach { obj -> emit(obj) } } .collect { obj -> println(" ARN: ${obj.resourceArn} Table name: ${obj.tableName}") } } }
  • 有关API详细信息,请参阅ListTables中的 Kotlin AWS SDK API 参考

以下代码示例演示如何使用 RestoreTable

SDK对于 Kotlin 来说
注意

还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库中进行设置和运行。

suspend fun restoreTable( keyspaceName: String?, utc: ZonedDateTime, ) { // Create an aws.smithy.kotlin.runtime.time.Instant value. val timeStamp = aws.smithy.kotlin.runtime.time .Instant(utc.toInstant()) val restoreTableRequest = RestoreTableRequest { restoreTimestamp = timeStamp sourceTableName = "MovieKotlin" targetKeyspaceName = keyspaceName targetTableName = "MovieRestore" sourceKeyspaceName = keyspaceName } KeyspacesClient { region = "us-east-1" }.use { keyClient -> val response = keyClient.restoreTable(restoreTableRequest) println("The ARN of the restored table is ${response.restoredTableArn}") } }
  • 有关API详细信息,请参阅RestoreTable中的 Kotlin AWS SDK API 参考

以下代码示例演示如何使用 UpdateTable

SDK对于 Kotlin 来说
注意

还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库中进行设置和运行。

suspend fun updateTable( keySpace: String?, tableNameVal: String?, ) { val def = ColumnDefinition { name = "watched" type = "boolean" } val tableRequest = UpdateTableRequest { keyspaceName = keySpace tableName = tableNameVal addColumns = listOf(def) } KeyspacesClient { region = "us-east-1" }.use { keyClient -> keyClient.updateTable(tableRequest) } }
  • 有关API详细信息,请参阅UpdateTable中的 Kotlin AWS SDK API 参考