Ejemplos de código de DynamoDB con los SDK de AWS
En los siguientes ejemplos de código se muestra cómo utilizar DynamoDB con un kit de desarrollo de software (SDK) de AWS.
Las acciones son extractos de código de programas más grandes y deben ejecutarse en contexto. Mientras las acciones muestran cómo llamar a las funciones de servicio individuales, es posible ver las acciones en contexto en los escenarios relacionados y en los ejemplos entre servicios.
Los escenarios son ejemplos de código que muestran cómo llevar a cabo una tarea específica llamando a varias funciones dentro del mismo servicio.
Los ejemplos con varios servicios son aplicaciones de muestra que funcionan con varios Servicios de AWS.
Para obtener una lista completa de las guías para desarrolladores del AWS SDK y ejemplos de código, consulte Uso de DynamoDB con un SDK de AWS. En este tema también se incluye información sobre cómo comenzar a utilizar el SDK y detalles sobre sus versiones anteriores.
Introducción
En los siguientes ejemplos de código, se muestra cómo empezar a utilizar DynamoDB.
- .NET
-
- AWS SDK for .NET
-
using Amazon.DynamoDBv2;
using Amazon.DynamoDBv2.Model;
namespace DynamoDB_Actions;
public static class HelloDynamoDB
{
static async Task Main(string[] args)
{
var dynamoDbClient = new AmazonDynamoDBClient();
Console.WriteLine($"Hello Amazon Dynamo DB! Following are some of your tables:");
Console.WriteLine();
// You can use await and any of the async methods to get a response.
// Let's get the first five tables.
var response = await dynamoDbClient.ListTablesAsync(
new ListTablesRequest()
{
Limit = 5
});
foreach (var table in response.TableNames)
{
Console.WriteLine($"\tTable: {table}");
Console.WriteLine();
}
}
}
- C++
-
- SDK para C++
-
Código del archivo de CMake CMakeLists.txt.
# Set the minimum required version of CMake for this project.
cmake_minimum_required(VERSION 3.13)
# Set the AWS service components used by this project.
set(SERVICE_COMPONENTS dynamodb)
# Set this project's name.
project("hello_dynamodb")
# Set the C++ standard to use to build this target.
# At least C++ 11 is required for the AWS SDK for C++.
set(CMAKE_CXX_STANDARD 11)
# Use the MSVC variable to determine if this is a Windows build.
set(WINDOWS_BUILD ${MSVC})
if (WINDOWS_BUILD) # Set the location where CMake can find the installed libraries for the AWS SDK.
string(REPLACE ";" "/aws-cpp-sdk-all;" SYSTEM_MODULE_PATH "${CMAKE_SYSTEM_PREFIX_PATH}/aws-cpp-sdk-all")
list(APPEND CMAKE_PREFIX_PATH ${SYSTEM_MODULE_PATH})
endif ()
# Find the AWS SDK for C++ package.
find_package(AWSSDK REQUIRED COMPONENTS ${SERVICE_COMPONENTS})
if (WINDOWS_BUILD AND AWSSDK_INSTALL_AS_SHARED_LIBS)
# Copy relevant AWS SDK for C++ libraries into the current binary directory for running and debugging.
# set(BIN_SUB_DIR "/Debug") # if you are building from the command line you may need to uncomment this
# and set the proper subdirectory to the executables' location.
AWSSDK_CPY_DYN_LIBS(SERVICE_COMPONENTS "" ${CMAKE_CURRENT_BINARY_DIR}${BIN_SUB_DIR})
endif ()
add_executable(${PROJECT_NAME}
hello_dynamodb.cpp)
target_link_libraries(${PROJECT_NAME}
${AWSSDK_LINK_LIBRARIES})
Código del archivo de código fuente hello_dynamodb.cpp.
#include <aws/core/Aws.h>
#include <aws/dynamodb/DynamoDBClient.h>
#include <aws/dynamodb/model/ListTablesRequest.h>
#include <iostream>
/*
* A "Hello DynamoDB" starter application which initializes an Amazon DynamoDB (DynamoDB) client and lists the
* DynamoDB tables.
*
* main function
*
* Usage: 'hello_dynamodb'
*
*/
int main(int argc, char **argv) {
Aws::SDKOptions options;
// Optionally change the log level for debugging.
// options.loggingOptions.logLevel = Utils::Logging::LogLevel::Debug;
Aws::InitAPI(options); // Should only be called once.
int result = 0;
{
Aws::Client::ClientConfiguration clientConfig;
// Optional: Set to the AWS Region (overrides config file).
// clientConfig.region = "us-east-1";
Aws::DynamoDB::DynamoDBClient dynamodbClient(clientConfig);
Aws::DynamoDB::Model::ListTablesRequest listTablesRequest;
listTablesRequest.SetLimit(50);
do {
const Aws::DynamoDB::Model::ListTablesOutcome &outcome = dynamodbClient.ListTables(
listTablesRequest);
if (!outcome.IsSuccess()) {
std::cout << "Error: " << outcome.GetError().GetMessage() << std::endl;
result = 1;
break;
}
for (const auto &tableName: outcome.GetResult().GetTableNames()) {
std::cout << tableName << std::endl;
}
listTablesRequest.SetExclusiveStartTableName(
outcome.GetResult().GetLastEvaluatedTableName());
} while (!listTablesRequest.GetExclusiveStartTableName().empty());
}
Aws::ShutdownAPI(options); // Should only be called once.
return result;
}
- Java
-
- SDK para Java 2.x
-
import software.amazon.awssdk.regions.Region;
import software.amazon.awssdk.services.dynamodb.DynamoDbClient;
import software.amazon.awssdk.services.dynamodb.model.DynamoDbException;
import software.amazon.awssdk.services.dynamodb.model.ListTablesRequest;
import software.amazon.awssdk.services.dynamodb.model.ListTablesResponse;
import java.util.List;
/**
* Before running this Java V2 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-java/latest/developer-guide/get-started.html
*/
public class ListTables {
public static void main(String[] args) {
System.out.println("Listing your Amazon DynamoDB tables:\n");
Region region = Region.US_EAST_1;
DynamoDbClient ddb = DynamoDbClient.builder()
.region(region)
.build();
listAllTables(ddb);
ddb.close();
}
public static void listAllTables(DynamoDbClient ddb) {
boolean moreTables = true;
String lastName = null;
while (moreTables) {
try {
ListTablesResponse response = null;
if (lastName == null) {
ListTablesRequest request = ListTablesRequest.builder().build();
response = ddb.listTables(request);
} else {
ListTablesRequest request = ListTablesRequest.builder()
.exclusiveStartTableName(lastName).build();
response = ddb.listTables(request);
}
List<String> tableNames = response.tableNames();
if (tableNames.size() > 0) {
for (String curName : tableNames) {
System.out.format("* %s\n", curName);
}
} else {
System.out.println("No tables found!");
System.exit(0);
}
lastName = response.lastEvaluatedTableName();
if (lastName == null) {
moreTables = false;
}
} catch (DynamoDbException e) {
System.err.println(e.getMessage());
System.exit(1);
}
}
System.out.println("\nDone!");
}
}
- JavaScript
-
- SDK para JavaScript (v3)
-
import { ListTablesCommand, DynamoDBClient } from "@aws-sdk/client-dynamodb";
const client = new DynamoDBClient({});
export const main = async () => {
const command = new ListTablesCommand({});
const response = await client.send(command);
console.log(response.TableNames.join("\n"));
return response;
};
