【shell】在shell中对HDFS文件及目录的判断

超、凢脫俗 2021-09-25 05:44 490阅读 0赞

在shell中判断文件是否存在可以通过`-f $fileName`进行判断，判断文件夹是否存在可以通过`-d $directory`进行判断，如以下脚本：  
[shell判断对文件和文件夹的判断][shell]

#!/bin/sh
    
    file="/opt/cdh-5.7.6/hadoop-2.6.0-cdh5.7.6/stop_all.sh"
    if [ ! -f "$file" ]; then
      echo "文件不存在！"
    else 
      echo "文件存在！"
    fi
    
    directory="/opt/cdh-5.7.6/hadoop-2.6.0-cdh5.7.6/"
    if [ ! -d "$directory" ]; then
      echo "文件夹不存在！"
    else 
      echo "文件夹存在！"
    fi

那么，怎么判断hdfs文件和文件夹是否存在呢？  
首先，我们来看看hdfs上的内置命令及参数

[fuyun@bigdata-training shell]$ hdfs dfs -help
    Usage: hadoop fs [generic options]
    	[-appendToFile <localsrc> ... <dst>]
    	[-cat [-ignoreCrc] <src> ...]
    	[-checksum <src> ...]
    	[-chgrp [-R] GROUP PATH...]
    	[-chmod [-R] <MODE[,MODE]... | OCTALMODE> PATH...]
    	[-chown [-R] [OWNER][:[GROUP]] PATH...]
    	[-copyFromLocal [-f] [-p] [-l] <localsrc> ... <dst>]
    	[-copyToLocal [-p] [-ignoreCrc] [-crc] <src> ... <localdst>]
    	[-count [-q] [-h] [-v] <path> ...]
    	[-cp [-f] [-p | -p[topax]] <src> ... <dst>]
    	[-createSnapshot <snapshotDir> [<snapshotName>]]
    	[-deleteSnapshot <snapshotDir> <snapshotName>]
    	[-df [-h] [<path> ...]]
    	[-du [-s] [-h] <path> ...]
    	[-expunge]
    	[-find <path> ... <expression> ...]
    	[-get [-p] [-ignoreCrc] [-crc] <src> ... <localdst>]
    	[-getfacl [-R] <path>]
    	[-getfattr [-R] { -n name | -d} [-e en] <path>]
    	[-getmerge [-nl] <src> <localdst>]
    	[-help [cmd ...]]
    	[-ls [-C] [-d] [-h] [-q] [-R] [-t] [-S] [-r] [-u] [<path> ...]]
    	[-mkdir [-p] <path> ...]
    	[-moveFromLocal <localsrc> ... <dst>]
    	[-moveToLocal <src> <localdst>]
    	[-mv <src> ... <dst>]
    	[-put [-f] [-p] [-l] <localsrc> ... <dst>]
    	[-renameSnapshot <snapshotDir> <oldName> <newName>]
    	[-rm [-f] [-r|-R] [-skipTrash] <src> ...]
    	[-rmdir [--ignore-fail-on-non-empty] <dir> ...]
    	[-setfacl [-R] [{ -b|-k} { -m|-x <acl_spec>} <path>]|[--set <acl_spec> <path>]]
    	[-setfattr { -n name [-v value] | -x name} <path>]
    	[-setrep [-R] [-w] <rep> <path> ...]
    	[-stat [format] <path> ...]
    	[-tail [-f] <file>]
    	[-test -[defsz] <path>]
    	[-text [-ignoreCrc] <src> ...]
    	[-touchz <path> ...]
    	[-usage [cmd ...]]
    
    ...........
    ...........
    -test -[defsz] <path> :
      Answer various questions about <path>, with result via exit status.
        -d  return 0 if <path> is a directory.
        -e  return 0 if <path> exists.
        -f  return 0 if <path> is a file.
        -s  return 0 if file <path> is greater than zero bytes in size.
        -z  return 0 if file <path> is zero bytes in size, else return 1.
    ..........
    ..........

参数解释说明：

*  \-d 如果路径是目录，返回0
 *  \-e 如果路径存在，返回0
 *  \-f 如果路径是文件，返回0
 *  \-s 如果文件的大小大于0字节则返回0
 *  \-z 如果文件的大小为0，则返回0，否则返回1

判断路径是否存在

#!/bin/sh
    
    hdfs dfs -test -e "/fuyun/"
    if [ $? -eq 0 ]; then
      echo "parth is exists!"
    else 
      echo "Error! parth is not exists!"
    fi

test命令还可以判断某个文件是否是文件夹、是否是文件、某个文件大小是否大于0或者等于0

#!/bin/sh
    
    hdfs dfs -test -e "/fuyun/"
    # 判断路径是否存在
    if [ $? -eq 0 ]; then
      echo "parth is exists!"
    else 
      echo "Error! parth is not exists!"
    fi
    
    # 判断是否为文件夹
    hdfs dfs -test -d "/fuyun/"
    if [ $? -eq 0 ]; then
      echo "parth is directory!"
    else 
      echo "parth is not directory!"
    fi
    
    # 判断是否为文件
    hdfs dfs -test -f "/fuyun/"
    if [ $? -eq 0 ]; then
      echo "parth is file!"
    else 
      echo "parth is not file!"
    fi
    
    # 判断路径的大小是否大于0 bytes
    hdfs dfs -test -s "/fuyun/"
    if [ $? -eq 0 ]; then
      echo "Is greater than zero bytes in size!"
    else 
      echo "Is not greater than zero bytes in size!"
    fi
    
    # 判断路径的大小是否等于0 bytes
    hdfs dfs -test -s "/fuyun/"
    if [ $? -eq 0 ]; then
      echo "Is zero bytes in size!"
    else 
      echo "Is not zero bytes in size!"
    fi

[shell]: https://blog.csdn.net/lz6363/article/details/115035302