环境依赖
HADOOP-COS 与对应版本的 cos_api-bundle。
DataX 版本：DataX-3.0。
下载与安装
获取 HADOOP-COS
获取 DataX 软件包
安装 HADOOP-COS
下载 HADOOP-COS 后，将
hadoop-cos-2.x.x-${version}.jar 和 cos_api-bundle-${version}.jar 拷贝到 Datax 解压路径plugin/reader/hdfsreader/libs/以及plugin/writer/hdfswriter/libs/下。使用方法
DataX 配置
修改 datax.py 脚本
打开 DataX 解压目录下的 bin/datax.py 脚本，修改脚本中的 CLASS_PATH 变量为如下：
CLASS_PATH = ("%s/lib/*:%s/plugin/reader/hdfsreader/libs/*:%s/plugin/writer/hdfswriter/libs/*:.") % (DATAX_HOME, DATAX_HOME, DATAX_HOME)
在配置 JSON 文件里配置 hdfsreader 和 hdfswriter
示例 JSON 如下：
{"job": {"setting": {"speed": {"byte": 10485760},"errorLimit": {"record": 0,"percentage": 0.02}},"content": [{"reader": {"name": "hdfsreader","parameter": {"path": "testfile","defaultFS": "cosn://examplebucket-1250000000/","column": ["*"],"fileType": "text","encoding": "UTF-8","hadoopConfig": {"fs.cosn.impl": "org.apache.hadoop.fs.CosFileSystem","fs.cosn.userinfo.region": "ap-beijing","fs.cosn.tmp.dir": "/tmp/hadoop_cos","fs.cosn.userinfo.secretId": "COS_SECRETID","fs.cosn.userinfo.secretKey": "COS_SECRETKEY"},"fieldDelimiter": ","}},"writer": {"name": "hdfswriter","parameter": {"path": "/user/hadoop/","fileName": "testfile1","defaultFS": "cosn://examplebucket-1250000000/","column": [{"name": "col","type": "string"},{"name": "col1","type": "string"},{"name": "col2","type": "string"}],"fileType": "text","encoding": "UTF-8","hadoopConfig": {"fs.cosn.impl": "org.apache.hadoop.fs.CosFileSystem","fs.cosn.userinfo.region": "ap-beijing","fs.cosn.tmp.dir": "/tmp/hadoop_cos","fs.cosn.userinfo.secretId": "COS_SECRETID","fs.cosn.userinfo.secretKey": "COS_SECRETKEY"},"fieldDelimiter": ":","writeMode": "append"}}}]}}
配置说明如下：
hadoopConfig 配置为 cosn 所需要的配置。
defaultFS 填写为 cosn 的路径，例如
cosn://examplebucket-1250000000/。fs.cosn.userinfo.region 修改为存储桶所在的地域，例如
ap-beijing，详情请参见 地域和访问域名。COS_SECRETID 和 COS_SECRETKEY 修改为 COS 密钥。
其他配置同 hdfs 配置项即可。
执行数据迁移
将配置文件保存为 hdfs_job.json，存放到 job 目录下，执行以下命令行：
bin/datax.py job/hdfs_job.json
观察屏幕正常输出如下：
2020-03-09 16:49:59.543 [job-0] INFO JobContainer -[total cpu info] =>averageCpu | maxDeltaCpu | minDeltaCpu-1.00% | -1.00% | -1.00%[total gc info] =>NAME | totalGCCount | maxDeltaGCCount | minDeltaGCCount | totalGCTime | maxDeltaGCTime | minDeltaGCTimePS MarkSweep | 1 | 1 | 1 | 0.024s | 0.024s | 0.024sPS Scavenge | 1 | 1 | 1 | 0.014s | 0.014s | 0.014s2020-03-09 16:49:59.543 [job-0] INFO JobContainer - PerfTrace not enable!2020-03-09 16:49:59.543 [job-0] INFO StandAloneJobContainerCommunicator - Total 2 records, 33 bytes | Speed 3B/s, 0 records/s | Error 0 records, 0 bytes | All Task WaitWriterTime 0.000s | All Task WaitReaderTime 0.033s | Percentage 100.00%2020-03-09 16:49:59.544 [job-0] INFO JobContainer -任务启动时刻 : 2020-03-09 16:49:48任务结束时刻 : 2020-03-09 16:49:59任务总计耗时 : 11s任务平均流量 : 3B/s记录写入速度 : 0rec/s读出记录总数 : 2读写失败总数 : 0
