feat(unitproc):Created appendArgTar: appends bashvar as file to tar

Created appendArgTar function which appends a provided bash variable
to a specified tar archive using a specified temporary staging file
directory. It does not create a tar and will exit if the write
operation fails.

diff --git a/unitproc/bktemp-appendArgTar b/unitproc/bktemp-appendArgTar
new file mode 100644 (file)
index 0000000..b73f9b0
--- /dev/null
+++ b/unitproc/bktemp-appendArgTar
@@ -0,0 +1,60 @@
+#!/bin/bash
+
+# Desc: Template function to write data supplied as argument
+
+yell() { echo "$0: $*" >&2; } # Yell, Die, Try Three-Fingered Claw technique; # Ref/Attrib: https://stackoverflow.com/a/25515370
+die() { yell "$*"; exit 111; }
+try() { "$@" || die "cannot $*"; }
+appendArgTar(){
+    # Desc: Writes first argument to temporary file with arguments as options, then appends file to tar
+    # Usage: writeArg "$(echo "Data to be written.")" [name of file to be inserted] [tar path] [temp dir] ([cmd1] [cmd2] [cmd3] [cmd4]...)
+    # Input: arg1: data to be written
+    #        arg2: file name of file to be inserted into tar
+    #        arg3: tar archive path (must exist first)
+    #        arg4: temporary working dir
+    #        arg5+: command strings (ex: "gpsbabel -i nmea -f - -o kml -F - ")
+    # Output: file written to disk
+    # Example: decrypt multiple large files in parallel
+    #          appendArgTar "$(cat /tmp/largefile1.gpg)" "largefile1" $HOME/archive.tar /tmp "gpg --decrypt" &
+    #          appendArgTar "$(cat /tmp/largefile2.gpg)" "largefile2" $HOME/archive.tar /tmp "gpg --decrypt" &
+    #          appendArgTar "$(cat /tmp/largefile3.gpg)" "largefile3" $HOME/archive.tar /tmp "gpg --decrypt" &
+
+    # Depends: bash 5
+
+    # Set file name
+    if ! [ -z "$2" ]; then FILENAME="$2"; else yell "ERROR:Not enough arguments."; exit 1; fi
+    
+    # Check tar path is a file
+    if [ -f "$3" ]; then TAR_PATH="$3"; else yell "ERROR:Tar archive arg not a file."; exit 1; fi
+       
+    # Check temp dir arg
+    if ! [ -z "$4" ]; then TMP_DIR="$3"; else yell "ERROR:No temporary working dir set."; exit 1; fi
+    
+    # Set command strings
+    if ! [ -z "$5" ]; then CMD1="$5"; else CMD1="tee /dev/null "; fi # command string 1
+    if ! [ -z "$6" ]; then CMD2="$6"; else CMD2="tee /dev/null "; fi # command string 2
+    if ! [ -z "$7" ]; then CMD3="$7"; else CMD3="tee /dev/null "; fi # command string 3
+    if ! [ -z "$8" ]; then CMD4="$8"; else CMD4="tee /dev/null "; fi # command string 4
+
+    # Debug
+    yell "CMD1:$CMD1"
+    yell "CMD2:$CMD2"
+    yell "CMD3:$CMD3"
+    yell "CMD4:$CMD4"
+    # Write to temporary working dir
+    echo "$1" | $CMD1 | $CMD2 | $CMD3 | $CMD4 > "$TMP_DIR"/"$FILENAME";
+
+    # Append to tar
+    try tar --append --directory="$TMP_DIR" --file="$TAR_PATH" "$FILENAME";
+
+} # Append Bash var to file appended to Tar archive
+
+#==BEGIN sample code==
+myFile="/tmp/$(date +%s)..original"
+echo "how are you doing?" > "$myFile"
+myVAR="$(cat $myFile)"
+writeArg "$myVAR" "$myFile..LOUD_CHILD" "tee /tmp/cloneityclone " "tr '[:lower:]' '[:upper:]'"
+#==END sample code==
+
+# Author: Steven Baltakatei Sandoval
+# License: GPLv3+