/brokers/topics/[topic] : 存储某个topic的partitions所有分配信息
Schema:{ "version": "版本编号目前固定为数字1", "partitions": { "partitionId编号": [ 同步副本组brokerId列表 ], "partitionId编号": [ 同步副本组brokerId列表 ], ....... }}Example:{ "version": 1, "partitions": {"0": [1, 2],"1": [2, 1],"2": [1, 2],}}说明：紫红色为patitions编号，蓝色为同步副本组brokerId列表 partition状态信息/brokers/topics/[topic]/partitions/[0...N] 其中[0..N]表示partition索引号
/brokers/topics/[topic]/partitions/[partitionId]/state
Schema:{"controller_epoch": 表示kafka集群中的中央控制器选举次数,"leader": 表示该partition选举leader的brokerId,"version": 版本编号默认为1,"leader_epoch": 该partition leader选举次数,"isr": [同步副本组brokerId列表]} Example:{ "controller_epoch": 1, "leader": 2, "version": 1, "leader_epoch": 0, "isr": [2, 1]}Broker注册信息
/brokers/ids/[0...N]
每个broker的配置文件中都需要指定一个数字类型的id(全局不可重复),此节点为临时znode(EPHEMERAL)
Schema:{"jmx_port": jmx端口号,"timestamp": kafka broker初始启动时的时间戳,"host": 主机名或ip地址,"version": 版本编号默认为1,"port": kafka broker的服务端端口号,由server.properties中参数port确定} Example:{ "jmx_port": 6061, "timestamp":"1403061899859" "version": 1, "host": "192.168.1.148", "port": 9092}Controller epoch
/controller_epoch -> int (epoch)
此值为一个数字,kafka集群中第一个broker第一次启动时为1，以后只要集群中center controller中央控制器所在broker变更或挂掉，就会重新选举新的center controller，每次center controller变更controller_epoch值就会 + 1;
Controller注册信息
/controller -> int (broker id of the controller) 存储center controller中央控制器所在kafka broker的信息
{"version": 版本编号默认为1,"brokerid": kafka集群中broker唯一编号,"timestamp": kafka broker中央控制器变更时的时间戳} Example:{ "version": 1, "brokerid": 3, "timestamp": "1403061802981"}
Consumer注册信息
每个consumer都有一个唯一的ID(consumerId可以通过配置文件指定,也可以由系统生成),此id用来标记消费者信息.
/consumers/[groupId]/ids/[consumerIdString]
是一个临时的znode,此节点的值为请看consumerIdString产生规则,即表示此consumer目前所消费的topic + partitions列表.
consumerId产生规则：
StringconsumerUuid = null; if(config.consumerId!=null && config.consumerId) consumerUuid = consumerId; else { String uuid = UUID.randomUUID() consumerUuid = "%s-%d-%s".format(InetAddress.getLocalHost.getHostName, System.currentTimeMillis, uuid.getMostSignificantBits().toHexString.substring(0,8)); } String consumerIdString = config.groupId + "_" + consumerUuid; Schema:{"version": 版本编号默认为1,"subscription": { //订阅topic列表"topic名称": consumer中topic消费者线程数},"pattern": "static","timestamp": "consumer启动时的时间戳"} Example:{"version": 1,"subscription": {"open_platform_opt_push_plus1": 5},"pattern": "static","timestamp": "1411294187842"}
Consumer owner
/consumers/[groupId]/owners/[topic]/[partitionId] -> consumerIdString + threadId索引编号
当consumer启动时,所触发的操作:
首先进行"Consumer Id注册";然后在"Consumer id 注册"节点下注册一个watch用来监听当前group中其他consumer的"退出"和"加入";只要此znode path下节点列表变更,都会触发此group下consumer的负载均衡.(比如一个consumer失效,那么其他consumer接管partitions)在"Broker id 注册"节点下,注册一个watch用来监听broker的存活情况;如果broker列表变更,将会触发所有的groups下的consumer重新balance. Consumer offset
/consumers/[groupId]/offsets/[topic]/[partitionId] -> long (offset)
用来跟踪每个consumer目前所消费的partition中最大的offset
此znode为持久节点,可以看出offset跟group_id有关,以表明当消费者组(consumer group)中一个消费者失效, 重新触发 balance,其他consumer可以继续消费.
Re-assign partitions
/admin/reassign_partitions
{ "fields":[ { "name":"version", "type":"int", "doc":"version id" }, { "name":"partitions", "type":{ "type":"array", "items":{ "fields":[ { "name":"topic", "type":"string", "doc":"topic of the partition to be reassigned" }, { "name":"partition", "type":"int", "doc":"the partition to be reassigned" }, { "name":"replicas", "type":"array", "items":"int", "doc":"a list of replica ids" } ], } "doc":"an array of partitions to be reassigned to new replicas" } } ]} Example:{ "version": 1, "partitions": [ { "topic": "Foo", "partition": 1, "replicas": [0, 1, 3] } ] }Preferred replication election
/admin/preferred_replica_election
{ "fields":[ { "name":"version", "type":"int", "doc":"version id" }, { "name":"partitions", "type":{ "type":"array", "items":{ "fields":[ { "name":"topic", "type":"string", "doc":"topic of the partition for which preferred replica election should be triggered" }, { "name":"partition", "type":"int", "doc":"the partition for which preferred replica election should be triggered" } ], } "doc":"an array of partitions for which preferred replica election should be triggered" } } ]} 例子: { "version": 1, "partitions": [ { "topic": "Foo", "partition": 1 }, { "topic": "Bar", "partition": 0 } ] }
删除topics
/admin/delete_topics
Schema:{ "fields": [ {"name": "version", "type": "int", "doc": "version id"}, {"name": "topics", "type": { "type": "array", "items": "string", "doc": "an array of topics to be deleted"} } ]} 例子:{ "version": 1, "topics": ["foo", "bar"]}Topic配置
/config/topics/[topic_name]
{ "version": 1, "config": { "config.a": "x", "config.b": "y", ... }}