style(unitproc/):Shorten names of template prefix (bktemp -> bkt)

[BK-2020-03.git] / unitproc / bkt-appendArgTar

diff --git a/unitproc/bkt-appendArgTar b/unitproc/bkt-appendArgTar
new file mode 100644 (file)
index 0000000..eadf648
--- /dev/null
+++ b/unitproc/bkt-appendArgTar
@@ -0,0 +1,77 @@
+#!/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 $*"; }
+appendArgTar(){
+    # Desc: Writes first argument to temporary file with arguments as options, then appends file to tar
+    # Usage: appendArgTar "$(echo "Data to be written.")" [name of file to be inserted] [tar path] [temp dir] ([cmd1] [cmd2] [cmd3] [cmd4]...)
+    # Version: 1.0.6
+    # 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" $HOME/archive.tar /tmp "gpg --decrypt" &
+    # Depends: bash 5, tar 1, yell()
+    # Ref/Attrib: Using 'eval' to construct command strings https://askubuntu.com/a/476533
+
+    local fn fileName tarPath tmpDir cmd0 cmd1 cmd2 cmd3 cmd4
+
+    # Save function name
+    fn="${FUNCNAME[0]}";
+    #yell "DEBUG:STATUS:$fn:Finished appendArgTar()."
+    
+    # Set file name
+    if ! [ -z "$2" ]; then fileName="$2"; else yell "ERROR:$fn:Not enough arguments."; exit 1; fi
+    
+    # Check tar path is a file
+    if [ -f "$3" ]; then tarPath="$3"; else yell "ERROR:$fn:Tar archive arg not a file."; exit 1; fi
+       
+    # Check temp dir arg
+    if ! [ -z "$4" ]; then tmpDir="$4"; else yell "ERROR:$fn:No temporary working dir set."; exit 1; fi
+    
+    # Set command strings
+    if ! [ -z "$5" ]; then cmd1="$5"; else cmd1="cat "; fi # command string 1
+    if ! [ -z "$6" ]; then cmd2="$6"; else cmd2="cat "; fi # command string 2
+    if ! [ -z "$7" ]; then cmd3="$7"; else cmd3="cat "; fi # command string 3
+    if ! [ -z "$8" ]; then cmd4="$8"; else cmd4="cat "; fi # command string 4
+
+    # Input command
+    cmd0="echo \"\$1\""
+
+    # # Debug
+    # yell "DEBUG:STATUS:$fn:cmd0:$cmd0"
+    # yell "DEBUG:STATUS:$fn:cmd1:$cmd1"
+    # yell "DEBUG:STATUS:$fn:cmd2:$cmd2"
+    # yell "DEBUG:STATUS:$fn:cmd3:$cmd3"
+    # yell "DEBUG:STATUS:$fn:cmd4:$cmd4"
+    # yell "DEBUG:STATUS:$fn:fileName:$fileName"
+    # yell "DEBUG:STATUS:$fn:tarPath:$tarPath"
+    # yell "DEBUG:STATUS:$fn:tmpDir:$tmpDir"
+    
+    # Write to temporary working dir
+    eval "$cmd0 | $cmd1 | $cmd2 | $cmd3 | $cmd4" > "$tmpDir"/"$fileName";
+
+    # Append to tar
+    try tar --append --directory="$tmpDir" --file="$tarPath" "$fileName";
+    #yell "DEBUG:STATUS:$fn:Finished appendArgTar()."
+} # Append Bash var to file appended to Tar archive
+
+#==BEGIN sample code==
+myTar="/tmp/$(date +%s).tar";
+myTmpDir="/dev/shm"
+try tar --create --file="$myTar" --files-from=/dev/null ;
+myVar="how are you doing?"
+appendArgTar "$myVar" "$(date +%s)..LOUD_insidetar" "$myTar" "$myTmpDir" "tee /tmp/$(date +%s)..outsidetar " "tr '[:lower:]' '[:upper:]'" && \
+    echo "Created $myTar using $myTmpDir as temp working dir."
+#==END sample code==
+
+# Author: Steven Baltakatei Sandoval
+# License: GPLv3+