unitproc/bktemp-appendFileTar

   1 #!/bin/bash
   2
   3 # Desc: Template function to write data supplied as argument
   4
   5 yell() { echo "$0: $*" >&2; } # Yell, Die, Try Three-Fingered Claw technique; # Ref/Attrib: https://stackoverflow.com/a/25515370
   6 die() { yell "$*"; exit 111; }
   7 try() { "$@" || die "cannot $*"; }
   8 appendFileTar(){
   9     # Desc: Processes first file and then appends to tar
  10     # Usage: appendFileTar [file path] [name of file to be inserted] [tar path] [temp dir] ([cmd1] [cmd2] [cmd3] [cmd4]...)
  11     # Version: 1.0.3
  12     # Input: arg1: path of file to be (processed and) written
  13     #        arg2: name to use for file inserted into tar
  14     #        arg3: tar archive path (must exist first)
  15     #        arg4: temporary working dir
  16     #        arg5+: command strings (ex: "gpsbabel -i nmea -f - -o kml -F - ")
  17     # Output: file written to disk
  18     # Example: decrypt multiple large files in parallel
  19     #          appendFileTar /tmp/largefile1.gpg "largefile1" $HOME/archive.tar /tmp "gpg --decrypt" &
  20     #          appendFileTar /tmp/largefile2.gpg "largefile2" $HOME/archive.tar /tmp "gpg --decrypt" &
  21     #          appendFileTar /tmp/largefile3.gpg "largefile3" $HOME/archive.tar /tmp "gpg --decrypt" &
  22     # Depends: bash 5, tar 1, yell()
  23
  24     local fn fileName tarPath tmpDir
  25
  26     # Save function name
  27     fn="${FUNCNAME[0]}";
  28     #yell "DEBUG:STATUS:$fn:Finished appendFileTar()."
  29
  30     # Set file name
  31     if ! [ -z "$2" ]; then fileName="$2"; else yell "ERROR:$fn:Not enough arguments."; exit 1; fi
  32     # Check tar path is a file
  33     if [ -f "$3" ]; then tarPath="$3"; else yell "ERROR:$fn:Tar archive arg not a file:$3"; exit 1; fi
  34     # Check temp dir arg
  35     if ! [ -z "$4" ]; then tmpDir="$4"; else yell "ERROR:$fn:No temporary working dir set."; exit 1; fi
  36     # Set command strings
  37     if ! [ -z "$5" ]; then cmd1="$5"; else cmd1="cat "; fi # command string 1
  38     if ! [ -z "$6" ]; then cmd2="$6"; else cmd2="cat "; fi # command string 2
  39     if ! [ -z "$7" ]; then cmd3="$7"; else cmd3="cat "; fi # command string 3
  40     if ! [ -z "$8" ]; then cmd4="$8"; else cmd4="cat "; fi # command string 4
  41
  42     # Input command string
  43     cmd0="cat \"\$1\""
  44
  45     # # Debug
  46     # yell "DEBUG:STATUS:$fn:cmd0:$cmd0"
  47     # yell "DEBUG:STATUS:$fn:cmd1:$cmd1"
  48     # yell "DEBUG:STATUS:$fn:cmd2:$cmd2"
  49     # yell "DEBUG:STATUS:$fn:cmd3:$cmd3"
  50     # yell "DEBUG:STATUS:$fn:cmd4:$cmd4"
  51     # yell "DEBUG:STATUS:$fn:fileName:$fileName"
  52     # yell "DEBUG:STATUS:$fn:tarPath:$tarPath"
  53     # yell "DEBUG:STATUS:$fn:tmpDir:$tmpDir"
  54
  55     # Write to temporary working dir
  56     eval "$cmd0 | $cmd1 | $cmd2 | $cmd3 | $cmd4" > "$tmpDir"/"$fileName";
  57
  58     # Append to tar
  59     try tar --append --directory="$tmpDir" --file="$tarPath" "$fileName";
  60     #yell "DEBUG:STATUS:$fn:Finished appendFileTar()."
  61 } # Append file to Tar archive
  62
  63 #==BEGIN sample code==
  64 myTar="/tmp/$(date +%s).tar";
  65 myTmpDir="/dev/shm";
  66 try tar --create --file="$myTar" --files-from=/dev/null ;
  67 myFile="/tmp/$(date +%s)..original";
  68 echo "how are you doing?" > "$myFile";
  69 appendFileTar "$myFile" "$(date +%s)..LOUD_insidetar" "$myTar" "$myTmpDir" "tee /tmp/$(date +%s)..outsidetar " "tr '[:lower:]' '[:upper:]'" && \
  70     echo "Inserted a processed version of $myFile into $myTar using temp dir $myTmpDir ";
  71 #==END sample code==
  72
  73 # Author: Steven Baltakatei Sandoval
  74 # License: GPLv3+