feat(exec):Add initial draft of pressure logging script

diff --git a/exec/bkplog.sh b/exec/bkplog.sh
new file mode 100755 (executable)
index 0000000..bfa9195
--- /dev/null
+++ b/exec/bkplog.sh
@@ -0,0 +1,74 @@
+#!/bin/bash
+
+# Date: 2020-04-10T04:32Z
+
+# Author: Steven Baltakatei Sandoval
+
+# License: 
+
+# Description: Logs pressure to a daily log file. Restarts daily at
+# UTC midnight.
+
+# Usage: plog.sh [ sensor script path ] [ output log dir path ]
+
+echoerr() { echo "$@" 1>&2 ; } # Define echo to stderr function.
+
+SENSOR_SCRIPT_PATH="$1" # Identify first argument as sensor script path.
+DIROUT1="$2" # Identify second argument as output log file directory path.
+
+SCRIPT_PATH="${0}" # [1]
+SCRIPT_BASENAME="$(basename "$SCRIPT_PATH")"
+SCRIPT_DIR="$(dirname "$SCRIPT_PATH")"
+SCRIPT_TIME_SHORT="$(date +%Y%m%dT%H%M%S%z)"
+SCRIPT_DATE_SHORT="$(date +%Y%m%d)"
+
+SCRIPT_ERROR_LOG_PATH=~/"$SCRIPT_DATE_SHORT""_""$SCRIPT_BASENAME"..error.log
+
+# Check that time synchronization service ('ntp') exists. Warn if it doesn't.
+if command -v ntp 1>/dev/null 2>&1; then echoerr "WARNING: ntp not found. Log timestamps may not be accurate."; fi
+
+# Main loop
+if [ -d "$DIROUT1" ] && [ -f "$SENSOR_SCRIPT_PATH" ] ; then # Check that output directory and sensor script file exist.
+    while true; do
+       echoerr "DEBUG:Starting while loop."
+       
+       # Update time constants
+       TIME_CURRENT="$(date --iso-8601=seconds)" ;
+       #echoerr "DEBUG:TIME_CURRENT is:""$TIME_CURRENT" ;
+       TIME_CURRENT_SHORT="$(date -d "$TIME_CURRENT" +%Y%m%dT%H%M%S%z)"
+       #echoerr "DEBUG:TIME_CURRENT_SHORT is""$TIME_CURRENT_SHORT"
+       DATE_CURRENT="$(date -d "$TIME_CURRENT" --iso-8601=date)" ;
+       #echoerr "DEBUG:DATE_CURRENT is:""$DATE_CURRENT" ;
+       DATE_CURRENT_SHORT="$(date -d "$TIME_CURRENT" +%Y%m%d)" ;
+       #echoerr "DEBUG:DATE_CURRENT is:""$DATE_CURRENT_SHORT" ;
+       DATE_TOMORROW="$(date -d "$TIME_CURRENT next day" --iso-8601=date)" ;
+       #echoerr "DEBUG:DATE_TOMORROW is:""$DATE_TOMORROW" ;
+       TIME_NEXT_MIDNIGHT="$(date -d "$DATE_TOMORROW" --iso-8601=seconds)" ;
+       #echoerr "DEBUG:TIME_NEXT_MIDNIGHT is:""$TIME_NEXT_MIDNIGHT" ;
+       ####SECONDS_UNTIL_NEXT_MIDNIGHT="$((  $(date +%s -d "$TIME_NEXT_MIDNIGHT") - $(date +%s -d "$TIME_CURRENT")  ))" ;
+       SECONDS_UNTIL_NEXT_MIDNIGHT="10" # DEBUG 10 second. Hail Satan.
+       #echoerr "DEBUG:SECONDS_UNTIL_NEXT_MIDNIGHT is:""$SECONDS_UNTIL_NEXT_MIDNIGHT" ;
+       if [ "$SECONDS_UNTIL_NEXT_MIDNIGHT" -eq 0 ]; then echoerr "WARNING:Is it exactly midnight?" ; continue; fi ; # Exit loop early if equal to 0 because "timeout 0s" never ends.
+       if [ "$SECONDS_UNTIL_NEXT_MIDNIGHT" -lt 0 ]; then echoerr "ERROR:Time until midnight error." ; exit 1; fi ; # Exit script if equal to 0 because "timeout 0s" never ends.
+       
+       # Update output file names.
+       DIROUTN="$DIROUT1" ;
+       FILEOUTN="$DATE_CURRENT_SHORT""..""$(hostname)""_pressure.csv" ;
+
+       # DEBUG
+       echoerr "SECONDS_UNTIL_NEXT_MIDNIGHT:""$SECONDS_UNTIL_NEXT_MIDNIGHT"
+       echoerr "SENSOR_SCRIPT_PATH         :""$SENSOR_SCRIPT_PATH"
+       echoerr "DIROUTN                    :""$DIROUTN"
+       echoerr "FILEOUTN                   :""$FILEOUTN"
+       
+       # Append pressure log until midnight.
+       timeout "$SECONDS_UNTIL_NEXT_MIDNIGHT""s" python2 "$SENSOR_SCRIPT_PATH" 1>> "$DIROUTN"/"$FILEOUTN" 2>&1 ; # log script data
+    done
+    
+else
+    echoerr "$SCRIPT_TIME_SHORT"">Sensor script file not found at: $SENSOR_SCRIPT_PATH or $DIROUT1 not found."
+    echo "$SCRIPT_TIME_SHORT"">Sensor script file not found at: $SENSOR_SCRIPT_PATH or $DIROUT1 not found." >> "$SCRIPT_ERROR_LOG_PATH" ; 
+fi
+
+# == References ==
+# 1. How to indicate script file name in a bash script. https://stackoverflow.com/a/3588939