我试图实现一个authenticatecallbackhandler，准备在kafka 2.0.0中发布，但没有效果-这是一个应该工作的设置吗？
在https://cwiki.apache.org/confluence/display/kafka/kip-86%3a+configurable+sasl+callback+handlers 我读到：
使用kafka中包含的saslserver实现进行sasl/plain身份验证时使用外部身份验证服务器
定义一个实现authenticatecallbackhandler的新类，该类处理namecallback和plainauthenticatecallback，并将该类添加到代理的sasl.server.callback.handler.class属性中。将为代理创建此回调处理程序的单个示例。配置的回调处理程序负责验证客户端提供的密码，这可能使用外部身份验证服务器。
所以基本上我所做的就是创建一个类：

package com.example;
import javax.security.auth.callback.Callback;
import javax.security.auth.callback.NameCallback;
import javax.security.auth.callback.UnsupportedCallbackException;
import javax.security.auth.login.AppConfigurationEntry;
import java.io.IOException;
import java.util.List;
import java.util.Map;
import org.apache.kafka.common.KafkaException;
import org.apache.kafka.common.security.auth.AuthenticateCallbackHandler;
import org.apache.kafka.common.security.plain.PlainAuthenticateCallback;
public class CustomAuthenticateCallbackHandler implements AuthenticateCallbackHandler {
    private List<AppConfigurationEntry> jaasConfigEntries;
    public void configure(Map<String, ?> configs, String mechanism, List<AppConfigurationEntry> jaasConfigEntries) {
        this.jaasConfigEntries = jaasConfigEntries;
    }
    public void handle(Callback[] callbacks) throws IOException, UnsupportedCallbackException {
        String username = null;
        for (Callback callback: callbacks) {
            if (callback instanceof NameCallback)
                username = ((NameCallback) callback).getDefaultName();
            else if (callback instanceof PlainAuthenticateCallback) {
                PlainAuthenticateCallback plainCallback = (PlainAuthenticateCallback) callback;
                boolean authenticated = authenticate(username, plainCallback.password());
                plainCallback.authenticated(authenticated);
            } else
                throw new UnsupportedCallbackException(callback);
        }
    }
    protected boolean authenticate(String username, char[] password) throws IOException {
        return username != null && username.equals("test") && new String(password).equals("test");
    }
    public void close() throws KafkaException {
    }
}

构建一个jar并使其可供kafka使用，如docker-compose.yml中所示：

version: '3'
services:
  zookeeper:
    image: confluentinc/cp-zookeeper:5.0.0-beta1-1
    ports:
      - "2181:2181"
    environment:
      ZOOKEEPER_CLIENT_PORT: 2181
      ZOOKEEPER_TICK_TIME: 2000
      ZOOKEEPER_SASL_ENABLED: "false"
  kafka:
    image: confluentinc/cp-kafka:5.0.0-beta1-1
    depends_on:
      - zookeeper
    volumes:
      - ./security:/etc/kafka/secrets
      - ./jars:/etc/kafka/jars
    ports:
      - "9092:9092"
    environment:
      CLASSPATH: /etc/kafka/jars/*
      ZOOKEEPER_SASL_ENABLED: "false"
      KAFKA_BROKER_ID: 1
      KAFKA_ZOOKEEPER_CONNECT: zookeeper:2181
      KAFKA_ADVERTISED_LISTENERS: SASL_PLAINTEXT://kafka:9092
      KAFKA_SECURITY_INTER_BROKER_PROTOCOL: SASL_PLAINTEXT
      KAFKA_SASL_ENABLED_MECHANISMS: PLAIN
      KAFKA_SASL_MECHANISM_INTER_BROKER_PROTOCOL: PLAIN
      KAFKA_AUTHORIZER_CLASS_NAME: kafka.security.auth.SimpleAclAuthorizer
      KAFKA_ALLOW_EVERYONE_IF_NO_ACL_FOUND: "false"
      KAFKA_SUPER_USERS: User:admin
      KAFKA_OPTS: -Djava.security.auth.login.config=/etc/kafka/secrets/broker_jaas.conf
      KAFKA_SASL_SERVER_CALLBACK_HANDLER_CLASS: com.example.CustomAuthenticateCallbackHandler

经纪人\ jaas.conf：

KafkaServer {
  org.apache.kafka.common.security.plain.PlainLoginModule required
  username="admin"
  password="admin-secret"
  user_admin="admin-secret"
  ;
};

cli-client.properties属性：

security.protocol=SASL_PLAINTEXT
sasl.mechanism=PLAIN
sasl.jaas.config=org.apache.kafka.common.security.plain.PlainLoginModule required \
  username="test" \
  password="test";

然后我用以下方法进行测试：

> kafka-console-producer --broker-list kafka:9092 --topic test-topic --producer.config /etc/kafka/secrets/cli-client.properties
 This is a message
 This is another message

但是，我得到一个生产者无法验证的错误：
[2018-05-17 19:49:06955]错误[producer clientid=console producer]连接到节点-1身份验证失败，原因：身份验证失败：用户名或密码无效（org.apache.kafka.clients.networkclient）