通过Maven运行本地版本的dynamodb时收到身份验证错误

Question

I'm using Maven to start a local copy of DynamoDb for testing.
For those that are interested, I've copied the instructions here https://thecarlhall.wordpress.com/2015/11/14/integration-testing-with-dynamodb-locally/ (and I've added them to the end of this question).

The problem is, when I try and create a client that accesses the local version of Dynamo, I get an error:

AmazonServiceException: The request signature we calculated does not match the signature you provided

Everything that I've read says that the secret is not checked when using a local dynamoDb, so my suspicion is that, for whatever reason, i'm accessing my real dynamodb. Can anyone see what i'm doing wrong?

AWSCredentials credentials = new BasicAWSCredentials(myAccessKey, "localTest");
AmazonDynamoDBClient client = new AmazonDynamoDBClient(credentials);

client.setEndpoint(dynamo.endpoint);
client.setRegion(Region.getRegion(Regions.EU_WEST_1));

Btw, the same is true for the setRegion. I should be able to set it to "local" but it's failing unless I set a real region.

I'm running my tests in IntelliJ, the maven setup is as follows:

<plugin>
    <groupId>com.googlecode.maven-download-plugin</groupId>
    <artifactId>download-maven-plugin</artifactId>
    <version>1.2.1</version>
    <executions>
        <execution>
            <id>install-dynamodb_local</id>
            <phase>pre-integration-test</phase>
            <goals>
                <goal>wget</goal>
            </goals>
            <configuration>
                <url>http://dynamodb-local.s3-website-${aws.s3.region}.amazonaws.com/dynamodb_local_latest.zip</url>
                <unpack>true</unpack>
                <outputDirectory>${project.build.directory}/dynamodb</outputDirectory>
            </configuration>
        </execution>
    </executions> 
</plugin> 
<plugin>
    <groupId>org.codehaus.mojo</groupId>
    <artifactId>build-helper-maven-plugin</artifactId>
    <version>1.9.1</version>
    <executions>
        <execution>
            <goals>
                <goal>reserve-network-port</goal>
            </goals>
            <phase>initialize</phase>
            <configuration>
                <portNames>
                    <portName>dynamodblocal.port</portName>
                </portNames>
            </configuration>
        </execution>
    </executions> 
</plugin> 
<plugin>
    <groupId>com.bazaarvoice.maven.plugins</groupId>
    <artifactId>process-exec-maven-plugin</artifactId>
    <version>0.7</version>
    <executions>
        <execution>
            <id>dynamodb_local</id>
            <phase>pre-integration-test</phase>
            <goals>
                <goal>start</goal>
            </goals>
            <configuration>
                <name>dynamodb_local</name>
                <waitAfterLaunch>1</waitAfterLaunch>
                <arguments>
                    <argument>java</argument>
                    <argument>-Djava.library.path=dynamodb/DynamoDBLocal_lib</argument>
                    <argument>-jar</argument>
                    <argument>dynamodb/DynamoDBLocal.jar</argument>
                    <argument>-port</argument>
                    <argument>${dynamodblocal.port}</argument>
                    <argument>-sharedDb</argument>
                    <argument>-inMemory</argument>
                </arguments>
            </configuration>
        </execution>
    </executions> 
</plugin>
<plugin>
    <groupId>org.apache.maven.plugins </groupId>
    <artifactId>maven-surefire-plugin</artifactId>
    <version>2.19</version>
    <configuration>
        <systemPropertyVariables>
            <dynamo.endpoint>http://localhost:${dynamodblocal.port}</dynamo.endpoint>
        </systemPropertyVariables>
    </configuration> 
</plugin>

Answer 1

I finally tracked this down.
My code has the following:

client.setEndpoint(dynamo.endpoint);
client.setRegion(Region.getRegion(Regions.EU_WEST_1));

An undocumented effect of setRegion is that it resets the endPoint back to amazon. By swapping these two statements around (as below), I resolved the problem.

client.setRegion(Region.getRegion(Regions.EU_WEST_1));
client.setEndpoint(dynamo.endpoint);

I hope this helps someone.