HdfsFindTool is essentially the HDFS version of the Linux file system find command. The command walks one or more HDFS directory trees, finds all HDFS files that match the specified expression, and applies selected actions to them. By default, it prints the list of matching HDFS file paths to stdout, one path per line.
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Search for exact filenames
For our example, lets assume our HDFS folder “/user/cloudera/test1/test1_child” contains below files$ hadoop fs -ls /user/cloudera/test1/test1_child Found 4 items -rw-r--r-- 1 cloudera cloudera 0 2017-10-22 06:42 /user/cloudera/test1/test1_child -rw-r--r-- 1 cloudera cloudera 0 2017-10-22 06:44 /user/cloudera/test1/test1_child/input1.txt -rw-r--r-- 1 cloudera cloudera 0 2017-10-22 06:46 /user/cloudera/test1/test1_child/input2.txt -rw-r--r-- 1 cloudera cloudera 0 2017-10-22 06:43 /user/cloudera/test1/test1_child/input3.txt We want to search for file named “input1.txt”
## Filename which matches the pattern $ export SOLR_JAR=/usr/lib/solr/contrib/mr/search-mr-job.jar; $ hdfs_find_location="/user/cloudera/test1/"; $ search_file_name_pattern="input1.txt" $ for var in `hadoop jar ${SOLR_JAR} org.apache.solr.hadoop.HdfsFindTool \ -find ${hdfs_find_location} -type f -name ${search_file_name_pattern} `; do echo ${var} done Output: hdfs://quickstart.cloudera:8020/user/cloudera/test1/test1_child/input1.txt -
Search for files which does not match the pattern(one or more patterns)
For our example, lets assume our HDFS folder “/user/cloudera/sample1” contains below files$ hadoop fs -ls /user/cloudera/sample1 Found 4 items -rw-r--r-- 1 cloudera cloudera 0 2017-10-22 06:42 /user/cloudera/sample1/_SUCCESS -rw-r--r-- 1 cloudera cloudera 0 2017-10-22 06:44 /user/cloudera/sample1/input1.tsv -rw-r--r-- 1 cloudera cloudera 0 2017-10-22 06:46 /user/cloudera/sample1/input2.tsv -rw-r--r-- 1 cloudera cloudera 0 2017-10-22 06:43 /user/cloudera/sample1/logs.tsv We want to search for files which does not match “_SUCCESS” and “logs.tsv”
## Filename which does not match the pattern $ export SOLR_JAR=/usr/lib/solr/contrib/mr/search-mr-job.jar; $ hdfs_find_location="/user/cloudera/sample1" $ for var in `hadoop jar ${SOLR_JAR} org.apache.solr.hadoop.HdfsFindTool \ -find ${hdfs_find_location} \ -type f ! -name "_SUCCESS" -a ! -name "logs.tsv" \ `; do echo ${var} done Output: hdfs://quickstart.cloudera:8020/user/cloudera/sample1 hdfs://quickstart.cloudera:8020/user/cloudera/sample1/input1.tsv hdfs://quickstart.cloudera:8020/user/cloudera/sample1/input2.tsv -
Perform set of operations on searched files, excluding the parent directory
For our example, lets assume our HDFS folder “/user/cloudera/sample2” contains below files.
We want to search for files which does not match “part-m-*”, copy those to a new location$ hadoop fs -ls /user/cloudera/sample2 Found 5 items -rw-r--r-- 1 cloudera cloudera 0 2017-10-22 10:19 /user/cloudera/sample2/corrupted_file -rw-r--r-- 1 cloudera cloudera 0 2017-10-22 10:15 /user/cloudera/sample2/part-m-00000 -rw-r--r-- 1 cloudera cloudera 0 2017-10-22 10:16 /user/cloudera/sample2/part-m-00001 -rw-r--r-- 1 cloudera cloudera 0 2017-10-22 10:17 /user/cloudera/sample2/part-r-00000 -rw-r--r-- 1 cloudera cloudera 0 2017-10-22 10:18 /user/cloudera/sample2/part-r-00001 # Script $ export SOLR_JAR=/usr/lib/solr/contrib/mr/search-mr-job.jar; $ hdfs_find_location="/user/cloudera/sample2" $ source_parent_directory="`basename ${hdfs_find_location}`"; $ hdfs_destination=/user/cloudera/sample3/ $ echo "This is a parent: ${source_parent_directory}"; $ echo "This is the destination: ${hdfs_destination}"; $ for source_to_be_copied in `hadoop jar ${SOLR_JAR} org.apache.solr.hadoop.HdfsFindTool \ -find ${hdfs_find_location} -type f ! -name 'part-m-*'` ; do ###Place your command below parent_directory=`basename ${source_to_be_copied}`; if [ "${parent_directory}" == "${source_parent_directory}" ]; then echo "This is a parent. Will not be copied: ${source_to_be_copied}"; else # Execute any command here # In this example, we are copying the files which did not match the pattern to a new location echo "Copying ${source_to_be_copied}"; hadoop fs -cp ${source_to_be_copied} ${hdfs_destination} fi done Output This is a parent. Will not be copied: hdfs://quickstart.cloudera:8020/user/cloudera/sample2 Copying hdfs://quickstart.cloudera:8020/user/cloudera/sample2/corrupted_file Copying hdfs://quickstart.cloudera:8020/user/cloudera/sample2/part-r-00000 Copying hdfs://quickstart.cloudera:8020/user/cloudera/sample2/part-r-00001 # Checking destination location for copied files $ hadoop fs -ls /user/cloudera/sample3/ Found 3 items -rw-r--r-- 1 cloudera cloudera 0 2017-10-22 11:57 /user/cloudera/sample3/corrupted_file -rw-r--r-- 1 cloudera cloudera 0 2017-10-22 11:59 /user/cloudera/sample3/part-r-00000 -rw-r--r-- 1 cloudera cloudera 0 2017-10-22 12:01 /user/cloudera/sample3/part-r-00001 -
To get command help
$ export SOLR_JAR=/usr/lib/solr/contrib/mr/search-mr-job.jar; $ hadoop jar ${SOLR_JAR} org.apache.solr.hadoop.HdfsFindTool -help Output: Usage: hadoop fs [generic options] [-find <path> ... <expression> ...] [-help [cmd ...]] [-usage [cmd ...]] -find <path> ... <expression> ... : Finds all files that match the specified expression and applies selected actions to them. The following primary expressions are recognised: -atime n -amin n Evaluates as true if the file access time subtracted from the start time is n days (or minutes if -amin is used). -blocks n Evaluates to true if the number of file blocks is n. -class classname [args ...] Executes the named expression class. -depth Always evaluates to true. Causes directory contents to be evaluated before the directory itself. -empty Evaluates as true if the file is empty or directory has no contents. -exec command [argument ...] -ok command [argument ...] Executes the specified Hadoop shell command with the given arguments. If the string {} is given as an argument then is replaced by the current path name. If a {} argument is followed by a + character then multiple paths will be batched up and passed to a single execution of the command. A maximum of 500 paths will be passed to a single command. The expression evaluates to true if the command returns success and false if it fails. If -ok is specified then confirmation of each command shall be prompted for on STDERR prior to execution. If the response is 'y' or 'yes' then the command shall be executed else the command shall not be invoked and the expression shall return false. -group groupname Evaluates as true if the file belongs to the specified group. -mtime n -mmin n Evaluates as true if the file modification time subtracted from the start time is n days (or minutes if -mmin is used) -name pattern -iname pattern Evaluates as true if the basename of the file matches the pattern using standard file system globbing. If -iname is used then the match is case insensitive. -newer file Evaluates as true if the modification time of the current file is more recent than the modification time of the specified file. -nogroup Evaluates as true if the file does not have a valid group. -nouser Evaluates as true if the file does not have a valid owner. -perm [-]mode -perm [-]onum Evaluates as true if the file permissions match that specified. If the hyphen is specified then the expression shall evaluate as true if at least the bits specified match, otherwise an exact match is required. The mode may be specified using either symbolic notation, eg 'u=rwx,g+x+w' or as an octal number. -print -print0 Always evaluates to true. Causes the current pathname to be written to standard output. If the -print0 expression is used then an ASCII NULL character is appended. -prune Always evaluates to true. Causes the find command to not descend any further down this directory tree. Does not have any affect if the -depth expression is specified. -replicas n Evaluates to true if the number of file replicas is n. -size n[c] Evaluates to true if the file size in 512 byte blocks is n. If n is followed by the character 'c' then the size is in bytes. -type filetype Evaluates to true if the file type matches that specified. The following file type values are supported: 'd' (directory), 'l' (symbolic link), 'f' (regular file). -user username Evaluates as true if the owner of the file matches the specified user. The following operators are recognised: expression -a expression expression -and expression expression expression Logical AND operator for joining two expressions. Returns true if both child expressions return true. Implied by the juxtaposition of two expressions and so does not need to be explicitly specified. The second expression will not be applied if the first fails. ! expression -not expression Evaluates as true if the expression evaluates as false and vice-versa. expression -o expression expression -or expression Logical OR operator for joining two expressions. Returns true if one of the child expressions returns true. The second expression will not be applied if the first returns true. -help [cmd ...] : Displays help for given command or all commands if none is specified. -usage [cmd ...] : Displays the usage for given command or all commands if none is specified. Generic options supported are -conf <configuration file> specify an application configuration file -D <property=value> use value for given property -fs <local|namenode:port> specify a namenode -jt <local|resourcemanager:port> specify a ResourceManager -files <comma separated list of files> specify comma separated files to be copied to the map reduce cluster -libjars <comma separated list of jars> specify comma separated jar files to include in the classpath. -archives <comma separated list of archives> specify comma separated archives to be unarchived on the compute machines. The general command line syntax is bin/hadoop command [genericOptions] [commandOptions]
Hello, I am getting following error. would you please check and let me know what I am missing.
testuser@abctest1:~#> hadoop jar /abc/sfw/cloudera/parcels/CDH/lib/solr/contrib/mr/search-mr-*-job.jar org.apache.solr.hadoop.HdfsFindTool -find hdfs:///tmp -mtime +7 -name * -type f
find: Unexpected argument: dead.letter
Try without the third bar: hadoop jar /abc/sfw/cloudera/parcels/CDH/lib/solr/contrib/mr/search-mr-*-job.jar org.apache.solr.hadoop.HdfsFindTool -find hdfs://tmp -mtime +7 -name * -type f