Pass packet metadata as arguments

DUP, QoS, RETAIN and the packet identifier

1 files changed, 7 insertions, 3 deletions

diff --git a/README.md b/README.md
index 8bf7818..24c635f 100644
--- a/README.md
+++ b/README.md
@@ -55,14 +55,19 @@ The routes follow the following format:
 On startup, `mqttr` will read the config file and subscribe to all the topics.
 When a message is received, `mqttr` will match the message topic against the
 routes and execute every program which is part of a matching route. Each program
-will have the message topic appended as an additional argument and will receive
-the message on stdin.
+will have the message topic as well as the DUP, QoS, RETAIN and Packet
+Identifier (when applicable) appended as an additional arguments (in that order)
+and will receive the message on stdin.
 
 An example program is this script:
 
 ```bash
 #!/usr/bin/env bash
 topic=$1
+dup=$2
+qos=$3
+retain=$4
+((qos == 1 || qos == 2)) && pkid=$5
 action=$(jq --raw-output .action)
 [[ $action == "toggle" ]] || exit 0
 mosquitto_pub --topic "zigbee2mqtt/light/set" --message '{"state":"TOGGLE"}'
@@ -75,7 +80,6 @@ it being ran every time a new MQTT message is published to this topic.
 
 * Configurable timeouts (eventually configurable per process)
 * Configurable QoS for each subscription (default is 0 (at most once))
-* Pass message metadata via the environment (QoS, retain, dup)
 * Configurable logging
 * Ability to configure programs with non-UTF-8 in paths
 * Maybe config reloading on SIGHUP