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

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

diff --git a/unitproc/bkt-dateShort b/unitproc/bkt-dateShort
new file mode 100644 (file)
index 0000000..5757eae
--- /dev/null
+++ b/unitproc/bkt-dateShort
@@ -0,0 +1,46 @@
+#!/bin/bash
+# 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 ([str date])
+    # Version: 1.1.2
+    # Input: arg1: 'date'-parsable timestamp string (optional)
+    # Output: stdout: date (ISO-8601, no separators)
+    # Depends: bash 5.0.3, date 8.30, yell()
+    local argTime timeCurrent timeInput dateCurrentShort
+
+    argTime="$1";
+    # Get Current Time
+    timeCurrent="$(date --iso-8601=seconds)" ; # Produce `date`-parsable current timestamp with resolution of 1 second.
+    # Decide to parse current or supplied date
+    ## Check if time argument empty
+    if [[ -z "$argTime" ]]; then
+       ## T: Time argument empty, use current time
+       timeInput="$timeCurrent";
+    else
+       ## F: Time argument exists, validate time
+       if date --date="$argTime" 1>/dev/null 2>&1; then
+           ### T: Time argument is valid; use it
+           timeInput="$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    
+    dateCurrentShort="$(date -d "$timeInput" +%Y%m%d)"; # Produce separator-less current date with resolution 1 day.
+    echo "$dateCurrentShort";
+} # Get YYYYmmdd
+
+#==BEGIN sample code==
+echo "The current day is          :$(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
+# License: GPLv3+