Example usage for org.apache.hadoop.security Credentials Credentials

Introduction

In this page you can find the example usage for org.apache.hadoop.security Credentials Credentials.

Prototype

public Credentials()

Source Link

Document

Create an empty credentials instance.

Usage

From source file:yarnkit.client.YarnClientService.java

License:Apache License

@Nullable
private static ByteBuffer getSecurityToken(@Nonnull Configuration conf) throws IOException {
    if (!UserGroupInformation.isSecurityEnabled()) {
        return null;
    }/*from  ww w .  j  a  v a  2 s  .  c  o  m*/
    FileSystem fs = FileSystem.get(conf);
    Credentials credentials = new Credentials();
    String tokenRenewer = conf.get(YarnConfiguration.RM_PRINCIPAL);
    if (tokenRenewer == null || tokenRenewer.length() == 0) {
        throw new IOException("Can't get Master Kerberos principal for the RM to use as renewer");
    }
    // For now, only getting tokens for the default file-system.
    final Token<?> tokens[] = fs.addDelegationTokens(tokenRenewer, credentials);
    if (tokens != null) {
        for (Token<?> token : tokens) {
            LOG.info("Got delegation token for " + fs.getUri() + ": " + token);
        }
    }
    DataOutputBuffer dob = new DataOutputBuffer();
    credentials.writeTokenStorageToStream(dob);
    return ByteBuffer.wrap(dob.getData(), 0, dob.getLength());
}