feat(unitproc):Add template timeUntilNextHour

[BK-2020-03.git] / unitproc / bktemp-timeUntilNextHour

diff --git a/unitproc/bktemp-timeUntilNextHour b/unitproc/bktemp-timeUntilNextHour
new file mode 100644 (file)
index 0000000..22ac290
--- /dev/null
+++ b/unitproc/bktemp-timeUntilNextHour
@@ -0,0 +1,49 @@
+#!/bin/bash
+# Desc: Template to report seconds until beginning of next hour
+# Author: Steven Baltaktei Sandoval; License: GPLv3+
+
+#==BEGIN Define script parameters==
+#===BEGIN Declare local script functions===
+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 $*"; }
+timeUntilNextHour(){
+    # Desc: Report seconds until next hour
+    # Output: stdout: integer seconds until next hour
+    # Output: exit code 0 if stdout > 0; 1 if stdout = 0; 2 if stdout < 0
+    # Usage: timeUntilNextHour
+    # Usage: if ! myTTL="$(timeUntilNextHour)"; then yell "ERROR in if statement"; exit 1; fi
+    local returnState
+    local TIME_CURRENT="$(date --iso-8601=seconds)"; # Produce `date`-parsable current timestamp with resolution of 1 second.
+    local TIME_NEXT_HOUR="$(date -d "$TIME_CURRENT next hour" --iso-8601=hours)"; # Produce `date`-parsable current time stamp with resolution of 1 second.
+    local SECONDS_UNTIL_NEXT_HOUR="$(( $(date +%s -d "$TIME_NEXT_HOUR") - $(date +%s -d "$TIME_CURRENT") ))"; # Calculate seconds until closest future midnight (res. 1 second).
+    if [[ "$SECONDS_UNTIL_NEXT_HOUR" -gt 0 ]]; then
+       returnState="true";
+    elif [[ "$SECONDS_UNTIL_NEXT_HOUR" -eq 0 ]]; then
+       returnState="WARNING_ZERO";
+       yell "WARNING:Reported time until next hour exactly zero.";
+    elif [[ "$SECONDS_UNTIL_NEXT_HOUR" -lt 0 ]]; then
+       returnState="WARNING_NEGATIVE";
+       yell "WARNING:Reported time until next hour is negative.";
+    fi
+
+    try echo "$SECONDS_UNTIL_NEXT_HOUR"; # Report
+    
+    #===Determine function return code===
+    if [[ "$returnState" = "true" ]]; then
+       return 0;
+    elif [[ "$returnState" = "WARNING_ZERO" ]]; then
+       return 1;
+    elif [[ "$returnState" = "WARNING_NEGATIVE" ]]; then
+       return 2;
+    fi
+} # Report seconds until next midnight
+#===END Declare local script functions===
+#==END Define script parameters==
+
+
+#==BEGIN sample code==
+try echo "Time until next hour (seconds):$(timeUntilNextHour)" # simple report
+
+if ! myTTL="$(timeUntilNextHour)"; then yell "ERROR in if statement for myTTL:$myTTL"; exit 1; fi # Use of exit code to exit early if time <= 0.
+#==END sample code==