Linux系统查看文件内容的特殊方法：
最基本的有cat和less,more，如果有特殊的要求的话。
1/如果只想看文件的前5行，可以使用head命令，如：
head -5 /etc/passwd
2/如果想查看文件的后10行，可以使用tail命令，如：
tail -10 /etc/passwd
3/参数-f使tail不停地去读最新的内容，这样有实时监视的效果：
tail -f /var/log/messages
定时调度工具的使用
1/各种工具聚集的网站：https://tool.lu/crontab
2/linux crontab 定时，crontab -e
然后在里面编辑：*/1 * * * * //1代表1分钟
3/vi log_generator.sh
4/把模拟生产日志的脚本generate_log.py执行脚本放进去：
python /home/hadoop/data/project/generate_log.py
5/添加sh执行权限
chmod u+x log_generator.sh
6/验证日志能否输出，在日志文件生成的文件目录下执行：tail -200f logs/access.log，定时监控
应用服务器产生access.log ==> 控制台输出
1/Flume配置：exec +memory +logger
2/配置文件accesslog_to_logger.conf
(exec-memory-logger)：先输出到控制台测试一下
exec-memory-logger.sources = exec-source
exec-memory-logger.sinks = logger-sink
exec-memory-logger.channels = memory-channel
exec-memory-logger.sources.exec-source.type = exec
exec-memory-logger.sources.exec-source.command = tail -F /home/hadoop/data/project/logs/access.log
exec-memory-logger.sources.exec-source.shell = /bin/sh -c
exec-memory-logger.channels.memory-channel.type = memory
exec-memory-logger.sinks.logger-sink.type = logger
exec-memory-logger.sources.exec-source.channels = memory-channel
exec-memory-logger.sinks.logger-sink.channel = memory-channel
3/启动flume-ng agent
flume-ng agent \
--name exec-memory-logger \
--conf $FLUME_HOME/conf \
--conf-file $FLUME_HOME/conf/accesslog_to_logger.conf \
-Dflume.root.logger=INFO,console
4/每隔1分钟即可在Flume控制台看到日志输出
日志文件==>Flume==>Kafka
1/启动zk：./zkServer.sh start
2/启动Kafka Server：kafka-server-start.sh -daemon $KAFKA_HOME/config/server.properties
3/修改Flume配置文件使得flume sink数据到Kafka
选型：exec-memory-kafka
type：org.apache.flume.sink.kafka.KafkaSink
brokerList、topic、requiredAck、batchSize
accesslog_to_kafka.conf
exec-memory-kafka.sources = exec-source
exec-memory-kafka.sinks = kafka-sink
exec-memory-kafka.channels = memory-channel
exec-memory-kafka.sources.exec-source.type = exec
exec-memory-kafka.sources.exec-source.command = tail -F /home/hadoop/data/project/logs/access.log
exec-memory-kafka.sources.exec-source.shell = /bin/sh -c
exec-memory-kafka.channels.memory-channel.type = memory
exec-memory-kafka.sinks.kafka-sink.type = org.apache.flume.sink.kafka.KafkaSink
exec-memory-kafka.sinks.kafka-sink.brokerList = hadoop:9092
exec-memory-kafka.sinks.kafka-sink.topic = flume-kafka-streaming-topic
exec-memory-kafka.sinks.kafka-sink.batchSize = 5
exec-memory-kafka.sinks.kafka-sink.requiredAcks = 1
exec-memory-kafka.sources.exec-source.channels = memory-channel
exec-memory-kafka.sinks.kafka-sink.channel = memory-channel
4/启动flume-ng agent
flume-ng agent \
--name exec-memory-kafka \
--conf $FLUME_HOME/conf \
--conf-file $FLUME_HOME/conf/accesslog_to_kafka.conf \
-Dflume.root.logger=INFO,console
5/启动kafka消费者进行消费
kafka-console-consumer.sh --zookeeper hadoop:2181 --topic flume-kafka-streaming-topic
6/代码消费
hadoop:2181 test flume-kafka-streaming-topic 1
package com.feiyue.bigdata.sparkstreaming
import org.apache.spark.SparkConf
import org.apache.spark.streaming.kafka.KafkaUtils
import org.apache.spark.streaming.{Seconds, StreamingContext}
object FlumeKafkaStreamingTest {
def main(args: Array[String]): Unit = {
if (args.length != 4) {
println("Usage: FlumeKafkaStreamingTest <zkQuorum> <group> <topics> <numThreads>")
System.exit(1)
}
val sparkConf = new SparkConf().setMaster("local[2]").setAppName("FlumeKafkaStreamingTest")
val ssc = new StreamingContext(sparkConf, Seconds(60))
val Array(zkQuorum, group, topics, numThreads) = args
val topicsMap = topics.split(",").map((_, numThreads.toInt)).toMap
val messages = KafkaUtils.createStream(ssc, zkQuorum, group, topicsMap)
messages.map(_._2).count().print()
ssc.start()
ssc.awaitTermination()
}
}
map(_._2) 等价于 map(t => t.2) //t是个2项以上的元组
map(._2, _) 等价与 map(t => t._2, t) //这会返回第二项为首后面项为旧元组的新元组
