MapReduce数据清
Posted hemomo
tags:
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说明:数据清洗的过程往往只需要运行Mapper程序,不需要运行Reduce程序。
已采集到日志数据存入web.log文件中,其中一条日志格式如下:
101.206.68.147 - - [18/Sep/2018:20:05:16 +0000] "HEAD / HTTP/1.2" 200 20 "-" "DNSPod-Monitor/1.0"
清洗目标:清除日志中字段长度比11小的日志记录。
具体代码如下:
项目1数据清洗一
新建包com.scitc.clean
1.编写LogMapper类:
package com.scitc.clean;
import java.io.IOException;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Mapper;
public class LogMapper extends Mapper<LongWritable, Text, Text, NullWritable> {
Text k = new Text();
@Override
protected void map(LongWritable key, Text value, Context context) throws IOException, InterruptedException {
// 1 获取1行数据
String line = value.toString();
// 2 解析日志
boolean result = parseLog(line,context);
// 3 日志不合法退出
if (!result) {
return;
}
// 4 设置key
k.set(line);
// 5 写出数据
context.write(k, NullWritable.get());
}
/**
* 功能:解析日志
* @param line 日志内容
* @param context 上下文对象
* @return
*/
private boolean parseLog(String line, Context context) {
// 1 截取
String[] fields = line.split(" ");
// 2 日志长度大于11的为合法
if (fields.length > 11) {
// 系统计数器
context.getCounter("map", "true").increment(1);
return true;
}else {
context.getCounter("map", "false").increment(1);
return false;
}
}
}
2.编写LogDriver类
package com.scitc.clean;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
public class LogDriver {
public static void main(String[] args) throws Exception {
//设置输入输出路径设置
args = new String[] { "E:/hadoop开发文件/input", "E:/hadoop开发文件/output" };
//1 获取job信息
Configuration conf = new Configuration();
Job job = Job.getInstance(conf);
//2 加载jar包
job.setJarByClass(LogDriver.class);
//3 关联map
job.setMapperClass(LogMapper.class);
//4 设置最终输出类型
job.setOutputKeyClass(Text.class);
job.setOutputValueClass(NullWritable.class);
//设置reducetask个数为0
job.setNumReduceTasks(0);
// 5 设置输入和输出路径
FileInputFormat.setInputPaths(job, new Path(args[0]));
FileOutputFormat.setOutputPath(job, new Path(args[1]));
//6 提交job
job.waitForCompletion(true);
} }
本地测试:
右键LogDriver类àrun asàjava application
即可在输出目录查看到清洗后的数据。
也可以打包、上传、在集群上运行,但注意修改输入、输出路径。
项目2数据清洗二
通过自定义的Bean对象封装清洗后的日志数据。
1.编写UpLogBean类
package com.scitc.clean;
public class UpLogBean {
private String remote_addr;// 记录客户端的ip地址
private String remote_user;// 记录客户端用户名称,忽略属性"-"
private String time_local;// 记录访问时间与时区
private String request;// 记录请求的url与http协议
private String status;// 记录请求状态;成功是200
private String body_bytes_sent;// 记录发送给客户端文件主体内容大小
private String http_referer;// 用来记录从那个页面链接访问过来的
private String http_user_agent;// 记录客户浏览器的相关信息
private boolean valid = true;// 判断数据是否合法
public String getRemote_addr() {
return remote_addr;
}
public void setRemote_addr(String remote_addr) {
this.remote_addr = remote_addr;
}
public String getRemote_user() {
return remote_user;
}
public void setRemote_user(String remote_user) {
this.remote_user = remote_user;
}
public String getTime_local() {
return time_local;
}
public void setTime_local(String time_local) {
this.time_local = time_local;
}
public String getRequest() {
return request;
}
public void setRequest(String request) {
this.request = request;
}
public String getStatus() {
return status;
}
public void setStatus(String status) {
this.status = status;
}
public String getBody_bytes_sent() {
return body_bytes_sent;
}
public void setBody_bytes_sent(String body_bytes_sent) {
this.body_bytes_sent = body_bytes_sent;
}
public String getHttp_referer() {
return http_referer;
}
public void setHttp_referer(String http_referer) {
this.http_referer = http_referer;
}
public String getHttp_user_agent() {
return http_user_agent;
}
public void setHttp_user_agent(String http_user_agent) {
this.http_user_agent = http_user_agent;
}
public boolean isValid() {
return valid;
}
public void setValid(boolean valid) {
this.valid = valid;
}
@Override
public String toString() {
StringBuilder sb = new StringBuilder();
sb.append(this.valid);
sb.append(" 01").append(this.remote_addr);
sb.append(" 01").append(this.remote_user);
sb.append(" 01").append(this.time_local);
sb.append(" 01").append(this.request);
sb.append(" 01").append(this.status);
sb.append(" 01").append(this.body_bytes_sent);
sb.append(" 01").append(this.http_referer);
sb.append(" 01").append(this.http_user_agent);
return sb.toString();
} }
2.编写UpLogMapper类
package com.scitc.clean;
import java.io.IOException;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Mapper;
public class UpLogMapper extends Mapper<LongWritable, Text, Text, NullWritable> {
Text k = new Text();
@Override
protected void map(LongWritable key, Text value, Context context) throws IOException, InterruptedException {
// 1 获取1行
String line = value.toString();
// 2 解析日志是否合法
UpLogBean bean = parseLog(line);
if (!bean.isValid()) {
return;
}
k.set(bean.toString());
// 3 输出
context.write(k, NullWritable.get());
}
// 解析日志
private UpLogBean parseLog(String line) {
UpLogBean logBean = new UpLogBean();
// 1 截取
String[] fields = line.split(" ");
if (fields.length > 11) {
// 2封装数据
logBean.setRemote_addr(fields[0]);
logBean.setRemote_user(fields[1]);
logBean.setTime_local(fields[3].substring(1));
logBean.setRequest(fields[6]);
logBean.setStatus(fields[8]);
logBean.setBody_bytes_sent(fields[9]);
logBean.setHttp_referer(fields[10]);
if (fields.length > 12) {
logBean.setHttp_user_agent(fields[11] + " "+ fields[12]);
}else {
logBean.setHttp_user_agent(fields[11]);
}
//大于400,HTTP错误
if (Integer.parseInt(logBean.getStatus()) >= 400) {
logBean.setValid(false);
}
}else {
logBean.setValid(false);
}
return logBean;
} }
3.编写UpLogDriver类
package com.scitc.clean;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
public class UpLogDriver {
public static void main(String[] args) throws Exception {
args = new String[] { "E:/hadoop开发文件/input", "E:/hadoop开发文件/upoutput" };
// 1 获取job信息
Configuration conf = new Configuration();
Job job = Job.getInstance(conf);
// 2 加载jar包
job.setJarByClass(UpLogDriver.class);
// 3 关联map
job.setMapperClass(UpLogMapper.class);
// 4 设置最终输出类型
job.setOutputKeyClass(Text.class);
job.setOutputValueClass(NullWritable.class);
// 5 设置输入和输出路径
FileInputFormat.setInputPaths(job, new Path(args[0]));
FileOutputFormat.setOutputPath(job, new Path(args[1]));
// 6 提交
job.waitForCompletion(true);
} }
本地测试:
右键UpLogDriver类àrun asàjava application
即可在输出目录查看到清洗后的数据。
也可以打包、上传、在集群上运行,但注意修改输入、输出路径。
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