temperatuur

#!/usr/bin/env bash

###############################################################################
# Made by    : Ewoud Dronkert
# Licence    : GNU GPL v3
# Platform   : Raspberry Pi, Raspbian
# Requires   : bash, curl, convert, ffmpeg, rsync, mail (msmtp),
#              remote server with ssh key access
# Location   : /usr/local/bin
# Name       : temperatuur
# Version    : 1.0.2
# Date       : 2021-08-31
# Purpose    : Download new KNMI temperature chart every 20 minutes, make
#              daily video of collected images, upload to webserver.
# How to use : Start as a system service
#              or from /etc/rc.local as "temperatuur &"
#              or from the command line as "sudo nohup temperatuur &"
# Settings   : DATA = web location of fresh image file
#              LDIR = local directory for saving images and videos
#              ID = SSH key for access to remote server
#              RUSER/RHOST/RDIR = server info
#              TONAME/TOADDR = email info
#              URL = public address of the video directory
###############################################################################

DATA='https://cdn.knmi.nl/knmi/map/page/weer/actueel-weer/temperatuur.png'
LDIR='/home/pi/knmi/'      # Local directory on the Pi running this script
ID='/home/pi/.ssh/id_rsa'  # SSH key with access to the server

RUSER=''                 # Username with ssh access to the server
RHOST='shell.xs4all.nl'  # Server with ssh/scp/rsync access
RDIR='WWW/knmi/'         # Remote directory on the server, relative to ssh login

FROMNAME='Pi Home'  # Sender name to use on the new video notification mail
TONAME=''           # Recipient name to use on the new video notification mail
TOADDR=''           # Where to send the new video notification mail

URL="https://$RUSER.home.xs4all.nl/knmi/"
SRV="$RUSER@$RHOST:$RDIR"   # Where to upload the video

###############################################################################

PRE='img-'  # To distinguish from downloaded files when removing
FMT='%03d'  # Three digit format 000-999 needed for 6*24=144 images per day
SUF='.png'
DIM='640x640'  # Convert downloaded images to these dimensions, mp4 compatible

PREV=25
while true; do

	H=$(date +%-H)
	if (( H < PREV )); then

		# New day
		YDAY=$(date -dyesterday +%Y%m%d)

		# Count number of saved image files from yesterday
		# Ignore error if none found
		n=$(ls "$LDIR$YDAY"*"$SUF" 2>/dev/null | wc -l)

		if (( n == 1 )); then

			# Just one image from yesterday, might as well upload it I guess
			SRC=$(ls "$LDIR$YDAY"*"$SUF")
			DST="temperatuur-$YDAY$SUF"
			rsync -qau -e "ssh -i '$ID'" "$SRC" "$SRV$DST"
			mv -f "$SRC" "$LDIR$DST"

		elif (( n > 1 )); then

			# Delete all image (but not video) files older than yesterday
			#FIRST=$(ls "$LDIR$YDAY"*"$SUF" | head -n1)
			#KEEP=$(basename "$FIRST")
			#find "$LDIR" -maxdepth 1 -type f -name "*$SUF" ! -newer "$FIRST" ! -name "$KEEP" -delete

			# Make room for new sequential files, delete the old ones
			rm -f "$LDIR$PRE"*"$SUF"

			# Rename yesterday's files sequentially
			i=0
			for f in "$LDIR$YDAY"*"$SUF"; do
				mv -f "$f" "$LDIR$PRE$(printf $FMT $i)$SUF"
				(( ++i ))
			done

			# Make video from sequential files
			VIDNAME="temperatuur-$YDAY.mp4"
			VID="$LDIR$VIDNAME"
			ffmpeg -y -hide_banner -r 8 -i "$LDIR$PRE$FMT$SUF" -an -r 8 -s $DIM -c:v libx264 -pix_fmt yuv420p "$VID" &>/dev/null

			# Process video if it exists
			if [[ -e "$VID" && -f "$VID" && -r "$VID" && -s "$VID" ]]; then

				chmod 644 "$VID"
				chown pi:pi "$VID"

				# Delete just processed files
				#rm -f "$LDIR$PRE"*"$SUF"

				# Upload, 3 tries
				for i in {1..3}; do
					rsync -qau -e "ssh -i '$ID'" "$VID" "$SRV$VIDNAME"
				done

				# Send mail notification of new video
				MAIL="To: $TONAME <$TOADDR>
From: $FROMNAME
Subject: Nieuwe temperatuurvideo

Nieuwe temperatuurvideo:
$URL$VIDNAME

Oudere video's staan op $URL

--
Dit is een automatisch verstuurde e-mail. Uw antwoord wordt niet gelezen."
				echo "$MAIL" | msmtp -t

			fi
		fi
	fi
	PREV=$H

	# Sleep until :04, :14, :24, :34, :44, :54
	M=$(date +%-M)                               # minutes of the clock
	while (( M >= 10 )); do (( M -= 10 )); done  # modulo 10
	(( N = 4 - M ))                              # time diff to next img of the interval
	if (( N < 0 )); then (( N += 10 )); fi       # no negative sleep
	sleep ${N}m                                  # sleep N minutes

	# Get KNMI temperature chart
	FILE="$LDIR$(date +%Y%m%d%H%M)$SUF"
	curl -s "$DATA" > "$FILE"
	if [ -e "$FILE" ]; then
		if [ -s "$FILE" ]; then
			ISPNG=$(file "$FILE" | grep -F 'PNG image')
			if [ -n "$ISPNG" ]; then

				convert "$FILE" \
					-strip \
					-define png:color-type=2 \
					-gravity center \
					-extent $DIM \
					"$FILE"
				chmod 644 "$FILE"
				chown pi:pi "$FILE"

			else
				rm -f "$FILE"
			fi
		else
			rm -f "$FILE"
		fi
	fi

done