Dynamo DB Local - 拒绝连接

Question

我正在尝试使用AWS Java SDK连接到Local Dynamo DB.所以我安装了Local Dynamo DB并启动了javascript shell.一切正常,shell从通常的地址开始http://localhost:8000/shell/

现在,当我尝试通过AWS SDK访问Dynamo数据库实例时,事情开始破裂.

这是我的代码:

public class MyDynamoDB {
    private AmazonDynamoDBClient client;

    public MyDynamoDB() {
        client = new AmazonDynamoDBClient();
        client.setEndpoint("http://localhost:8000");
    }

    public void saveAndLoad() {
        DynamoDBMapperConfig config = new DynamoDBMapperConfig(new TableNameOverride("xyz"));
        DynamoDBMapper mapper = new DynamoDBMapper(client, config);
        Data data = new Data();
        ...
        mapper.save(data);


        //check if persisted
        Data d = mapper.load(Data.class, "Key");
        if (d != null) {
            System.out.println(" Found data: " + d.getStuff());
        } else {
            System.out.println("Data not found");
        }
    }
}

在运行这个时,我得到以下堆栈跟踪

Nov 19, 2015 4:00:47 PM com.amazonaws.http.AmazonHttpClient executeHelper
INFO: Unable to execute HTTP request: Connection refused: connect
java.net.ConnectException: Connection refused: connect
at java.net.DualStackPlainSocketImpl.waitForConnect(Native Method)
at java.net.DualStackPlainSocketImpl.socketConnect(Unknown Source)
at java.net.AbstractPlainSocketImpl.doConnect(Unknown Source)
at java.net.AbstractPlainSocketImpl.connectToAddress(Unknown Source)
at java.net.AbstractPlainSocketImpl.connect(Unknown Source)
at java.net.PlainSocketImpl.connect(Unknown Source)
at java.net.SocksSocketImpl.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at org.apache.http.conn.scheme.PlainSocketFactory.connectSocket(PlainSocketFactory.java:117)
at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:177)
at org.apache.http.impl.conn.ManagedClientConnectionImpl.open(ManagedClientConnectionImpl.java:304)

Answer 1

您需要在命令提示符中触发DynamoDB ..

转到Dynamodb cli的安装位置并运行以下命令

java -Djava.library.path =./ DynamoDBLocal_lib -jar DynamoDBLocal.jar -sharedDb

验证它是否由http:// localhost:8000/shell /运行

Answer 2

刚刚遇到了同样的问题 - 在端点 url 中添加斜线为我解决了这个问题。

client.setEndpoint( "http://localhost:8000/");

Answer 3

如果您使用 SAM-LOCAL 或使用 eclipse 开发 aws lambda 函数，则此答案可能很有用。

Short Answer为环回分配 IP 别名以使用不同的地址到达 127.0.0.1，并将端点更新为该地址

从命令行运行

ifconfig lo0 alias 172.16.123.1

从 lambda 代码而不是访问http://localhost:8000/使用http://172.16.123.1:8000/

请参阅此链接以获取解释。

长答案

在 lambda 函数 pom 中

<dependency>
    <groupId>com.amazonaws</groupId>
    <artifactId>aws-java-sdk-dynamodb</artifactId>
    <version>1.11.313</version>
</dependency>

开始使用 dynomodb

java -Djava.library.path=./DynamoDBLocal_lib -jar DynamoDBLocal.jar -sharedDb

做IP别名

ifconfig lo0 alias 172.16.123.1

要从代码访问 DynmoDb，请执行

DynamoDB dynamoDb = new DynamoDB(AmazonDynamoDBClientBuilder.standard().withCredentials(new EnvironmentVariableCredentialsProvider()).withEndpointConfiguration(new AwsClientBuilder.EndpointConfiguration("http://172.16.123.1:8000/", "local")).build());

完成 lambda 函数的测试后，请执行以下操作

ifconfig lo0 -alias 172.16.123.1