GopherProxy

	mqtt-wrapper - brcon2024-hackathons - Bitreichcon 2024 Hackathons
	git clone git://bitreich.org/brcon2024-hackathons git://enlrupgkhuxnvlhsf6lc3fz…
	Log
	Files
	Refs
	Tags
	Submodules
	---
	mqtt-wrapper (1664B)
	---
	1 #!/bin/sh
	2 set -x
	3 #
	4 # $input_topic \| $runtime $runtime_args \| $output_topic
	5 # 2>$error_topic
	6 #
	7 # application to run
	8 runtime="${RUNTIME:-cat}"
	9 # arguments to $runtime
	10 runtime_args="${ARGS}"
	11 # stdin for $runtime; where others send to
	12 input_topics="${INPUT_TOPICS:-$$/in}"
	13 # stdout of $runtime; where others need to subscribe
	14 output_topic="${OUTPUT_TOPIC:-$$/out}"
	15 # stderr of $runtime; where others can subscribe
	16 error_topic="${ERROR_TOPIC:-$$/err}"
	17
	18 mqtt_broker="${MQTT_BROKER:-mx2.adamsgaard.dk}"
	19 mqtt_port="${MQTT_BROKER:-65431}"
	20 mqtt_user="${MQTT_USER:-bitreich}"
	21 mqtt_password="${MQTT_PASSWORD:-bitreich}"
	22 mosquitto_args="-h ${mqtt_broker} -p ${mqtt_port} -u ${mqtt_user} -P ${m…
	23
	24 cleanup() {
	25 kill -TERM -- -$$
	26 rm -f "$fin" "$fout" "$ferr"
	27 rmdir "$fifodir"
	28 exit 1
	29 }
	30
	31 die() {
	32 printf '%s: %s\n' "${0##*/}" "${1}" >&2
	33 cleanup
	34 exit "${2:-1}"
	35 }
	36
	37 fifodir="$(mktemp -d)" \|\| die 'mktemp'
	38 fin="${fifodir}/in"
	39 fout="${fifodir}/out"
	40 ferr="${fifodir}/err"
	41 mkfifo "$fin" "$fout" "$ferr" \|\| die 'mkfifo'
	42
	43 # split multiple input topics separated by "," into separate args
	44 subscribe_args="$(printf '%s' "$input_topics" \| sed 's/,/ -t /g')"
	45
	46 # subscribe to input topic(s), add -v option if you want message topic a…
	47 mosquitto_sub ${mosquitto_args} -t $subscribe_args >"${fin}" &
	48
	49 # create named pipes for output streams
	50 mosquitto_pub ${mosquitto_args} -t "${output_topic}" -l <"${fout}" &
	51 mosquitto_pub ${mosquitto_args} -t "${error_topic}" -l <"${ferr}" &
	52 trap -- 'cleanup' ERR INT HUP EXIT CHLD
	53
	54 # run the program (lossy restart if it fails), connecting to named pipes
	55 while :
	56 do
	57 $runtime $runtime_args <"${fin}" >"${fout}" 2>"${ferr}"
	58 done
	59