feat(unitproc):dateShort:Use arg as input date

diff --git a/unitproc/bktemp-dateShort b/unitproc/bktemp-dateShort
index 59d23f845a4f22b7ff081ba671097766c295730e..b4e4464e8b62bf915180c4366adfdf13f9d3039c 100644 (file)
--- a/unitproc/bktemp-dateShort
+++ b/unitproc/bktemp-dateShort
@@ -2,19 +2,45 @@
 
 # Desc: Template to display date
 
+yell() { echo "$0: $*" >&2; }      #o Yell, Die, Try Three-Fingered Claw technique
+die() { yell "$*"; exit 111; }     #o Ref/Attrib: https://stackoverflow.com/a/25515370
+try() { "$@" || die "cannot $*"; } #o
 dateShort(){
     # Desc: Date without separators (YYYYmmdd)
-    # Usage: dateShort
-    # Version: 1.0.0
+    # Usage: dateShort ([str date])
+    # Version: 1.1.0
+    # Input: arg1: 'date'-parsable timestamp string (optional)
     # Output: stdout: date (ISO-8601, no separators)
+    # Depends: yell
     local TIME_CURRENT DATE_CURRENT_SHORT
+
+    argTime="$1";
+    # Get Current Time
     TIME_CURRENT="$(date --iso-8601=seconds)" ; # Produce `date`-parsable current timestamp with resolution of 1 second.
-    DATE_CURRENT_SHORT="$(date -d "$TIME_CURRENT" +%Y%m%d)"; # Produce separator-less current date with resolution 1 day.
+    # Decide to parse current or supplied date
+    ## Check if time argument empty
+    if [[ -z "$argTime" ]]; then
+       ## T: Time argument empty, use current time
+       TIME_INPUT="$TIME_CURRENT";
+    else
+       ## F: Time argument exists, validate time
+       if date --date="$argTime" 1>/dev/null 2>&1; then
+           ### T: Time argument is valid; use it
+           TIME_INPUT="$argTime";
+       else
+           ### F: Time argument not valid; exit
+           yell "ERROR:Invalid time argument supplied. Exiting."; exit 1;
+       fi
+    fi
+    # Construct and deliver separator-les date string    
+    DATE_CURRENT_SHORT="$(date -d "$TIME_INPUT" +%Y%m%d)"; # Produce separator-less current date with resolution 1 day.
     echo "$DATE_CURRENT_SHORT";
 } # Get YYYYmmdd
 
 #==BEGIN sample code==
-echo "The current day is:$(dateShort)"
+echo "The current day is          :$(dateShort)";
+echo "Contact lost with STS-107 on:$(dateShort "2003-02-01T08:59:15-05:00")";
+echo "Bitcoin started on          :$(dateShort "@1231006505")";
 #==END sample code==
 
 # Author: Steven Baltakatei Sandoval