java.lang.IllegalArgumentException: hostname cannot be null when trying to obtain AWS ECR Authentication Token

问题

I am trying to obtain ECR authorisation token from AWS using aws-java-sdk version 1.11.339. I have created a class to do so as below:

public class ECRTokenGetter {
    private static final Logger LOGGER = LoggerFactory.getLogger(ECRTokenGetter.class);
    private static final int SINGLE_ELEMENT_INDEX = 0;


    public static String getEcrAuthorisationToken(Credentials creds, String awsRegion, String registryId) {
        LOGGER.debug("Obtaining temporary authorisation credentials from AWS ECR");

        AmazonECR ecrClient = AmazonECRClientBuilder.standard()
                .withRegion(awsRegion)
                .withCredentials(new AWSStaticCredentialsProvider(new BasicSessionCredentials(
                        creds.getAccessKeyId(),
                        creds.getSecretAccessKey(),
                        creds.getSessionToken())))
                .build();
        return ecrClient.getAuthorizationToken(new GetAuthorizationTokenRequest()
                        .withRegistryIds(registryId))
                .getAuthorizationData().get(SINGLE_ELEMENT_INDEX)
                .getAuthorizationToken();
    }
}

Unfortunately, when executing the code, I am getting following exception:

Exception in thread "main" java.lang.IllegalArgumentException: hostname cannot be null
    at com.amazonaws.util.AwsHostNameUtils.parseRegion(AwsHostNameUtils.java:79)
    at com.amazonaws.util.AwsHostNameUtils.parseRegionName(AwsHostNameUtils.java:59)
    at com.amazonaws.auth.internal.AWS4SignerRequestParams.resolveRegion(AWS4SignerRequestParams.java:121)
    at com.amazonaws.auth.internal.AWS4SignerRequestParams.<init>(AWS4SignerRequestParams.java:103)
    at com.amazonaws.auth.AWS4Signer.sign(AWS4Signer.java:225)
    at com.amazonaws.http.AmazonHttpClient$RequestExecutor.executeOneRequest(AmazonHttpClient.java:1212)
    at com.amazonaws.http.AmazonHttpClient$RequestExecutor.executeHelper(AmazonHttpClient.java:1058)
    at com.amazonaws.http.AmazonHttpClient$RequestExecutor.doExecute(AmazonHttpClient.java:743)
    at com.amazonaws.http.AmazonHttpClient$RequestExecutor.executeWithTimer(AmazonHttpClient.java:717)
    at com.amazonaws.http.AmazonHttpClient$RequestExecutor.execute(AmazonHttpClient.java:699)
    at com.amazonaws.http.AmazonHttpClient$RequestExecutor.access$500(AmazonHttpClient.java:667)
    at com.amazonaws.http.AmazonHttpClient$RequestExecutionBuilderImpl.execute(AmazonHttpClient.java:649)
    at com.amazonaws.http.AmazonHttpClient.execute(AmazonHttpClient.java:513)
    at com.amazonaws.services.ecr.AmazonECRClient.doInvoke(AmazonECRClient.java:1742)
    at com.amazonaws.services.ecr.AmazonECRClient.invoke(AmazonECRClient.java:1718)
    at com.amazonaws.services.ecr.AmazonECRClient.executeGetAuthorizationToken(AmazonECRClient.java:992)
    at com.amazonaws.services.ecr.AmazonECRClient.getAuthorizationToken(AmazonECRClient.java:966)
    at com.mycode.utils.ecr.aws.ECRTokenGetter.getEcrAuthorisationToken(ECRTokenGetter.java:27)
    at com.mycode.utils.ecr.AWSAuthTester.main(AWSAuthTester.java:32)

I can also observe the request object created by AWS SDK has a NULL host in the entrypoint, as can be seen in the picture below.

DefaultRequest object

How can I overcome this issue?

回答1:

It appears that the issue lied down in the String passed to the awsRegion parameter. In the following code

AmazonECR ecrClient = AmazonECRClientBuilder.standard()
            .withRegion(awsRegion)
            ...

if awsRegion is a String, it should use dashes as separators, e.g. "us-west-2", otherwise it should use Regions enum, e.g. Regions.US_WEST_2.

Alternative solution involves using withEndpointConfiguration instead of withRegion, e.g.

String ecrEndpoint = "ecr.%s.amazonaws.com";
AmazonECR ecrClient = AmazonECRClientBuilder.standard()
            .withEndpointConfiguration(new AwsClientBuilder.EndpointConfiguration(String.format(ecrEndpoint, awsRegion), awsRegion))
            ...

回答2:

I've just encountered the same issue.

The problem is that the URL has underscores (_).

In the class AmazonWebServiceClient there is a method called computeSignerByURI, that in the version I am using, this is the code:

private Signer computeSignerByURI(URI uri, String signerRegionOverride, boolean isRegionIdAsSignerParam) {
    if (uri == null) {
        throw new IllegalArgumentException("Endpoint is not set. Use setEndpoint to set an endpoint before performing any request.");
    }
    String service = getServiceNameIntern();
    String region = AwsHostNameUtils.parseRegionName(uri.getHost(), getEndpointPrefix());
    return computeSignerByServiceRegion(service, region, signerRegionOverride, isRegionIdAsSignerParam);
}

As you can see, there is a call to the .getHost() method in URI, that, when it's computed, it does not accept underscores, so, it returns null. Here you can check that.

回答3:

Values of a enum Regions should be converted to Strings with its method getName(). Otherwise enum's method name() or toString() returns a value as a text (with capital letters and underscores):

//Wrong conversion to a String
System.out.println(Regions.US_EAST_1);                     // result: US_EAST_1
System.out.println(String.format("%s",Regions.US_EAST_1)); // result: US_EAST_1
System.out.println(Regions.US_EAST_1.toString());          // result: US_EAST_1
System.out.println(Regions.US_EAST_1.name());              // result: US_EAST_1

//Correct conversion to a String
System.out.println(Regions.US_EAST_1.getName());           // result: us-east-1

As a result - the URL, defined for the request, is invalid:

来源：https://stackoverflow.com/questions/50720197/java-lang-illegalargumentexception-hostname-cannot-be-null-when-trying-to-obtai

标签

java

aws-java-sdk