Mosquitto 1.6 with MQTT v5 arrived

Some introduction might be written here.

Das (lange) erwartete MQTT5 ist scheinbar schon ne zeitlang bei Mosquitto dabei. Time flies…

MQTT5 Request-Response feature



root@eltiempo:~# mosquitto_rr --help
mosquitto_rr is an mqtt client that can be used to publish a request message and wait for a response.
             Defaults to MQTT v5, where the Request-Response feature will be used, but v3.1.1 can also be used
             with v3.1.1 brokers.
mosquitto_rr version 1.6.8 running on libmosquitto 1.6.8.

Usage: mosquitto_rr {[-h host] [-p port] [-u username] [-P password] -t topic | -L URL} -e response-topic
                    [-c] [-k keepalive] [-q qos] [-R]
                    [-F format]
                    [-W timeout_secs]
                    [-A bind_address]
                    [-i id] [-I id_prefix]
                    [-d] [-N] [--quiet] [-v]
                    [--will-topic [--will-payload payload] [--will-qos qos] [--will-retain]]
                    [{--cafile file | --capath dir} [--cert file] [--key file]
                      [--ciphers ciphers] [--insecure]
                      [--tls-alpn protocol]
                      [--tls-engine engine] [--keyform keyform] [--tls-engine-kpass-sha1]]
                     [--psk hex-key --psk-identity identity [--ciphers ciphers]]
                    [--proxy socks-url]
                    [-D command identifier value]
       mosquitto_rr --help

 -A : bind the outgoing socket to this host/ip address. Use to control which interface
      the client communicates over.
 -c : disable 'clean session' (store subscription and pending messages when client disconnects).
 -d : enable debug messages.
 -D : Define MQTT v5 properties. See the documentation for more details.
 -F : output format.
 -h : mqtt host to connect to. Defaults to localhost.
 -i : id to use for this client. Defaults to mosquitto_rr_ appended with the process id.
 -k : keep alive in seconds for this client. Defaults to 60.
 -L : specify user, password, hostname, port and topic as a URL in the form:
 -N : do not add an end of line character when printing the payload.
 -p : network port to connect to. Defaults to 1883 for plain MQTT and 8883 for MQTT over TLS.
 -P : provide a password
 -q : quality of service level to use for communications. Defaults to 0.
 -R : do not print stale messages (those with retain set).
 -t : mqtt response topic to subscribe to. May be repeated multiple times.
 -u : provide a username
 -v : print received messages verbosely.
 -V : specify the version of the MQTT protocol to use when connecting.
      Defaults to 5.
 -W : Specifies a timeout in seconds how long to wait for a response.
 --help : display this message.
 --quiet : don't print error messages.
 --will-payload : payload for the client Will, which is sent by the broker in case of
                  unexpected disconnection. If not given and will-topic is set, a zero
                  length message will be sent.
 --will-qos : QoS level for the client Will.
 --will-retain : if given, make the client Will retained.
 --will-topic : the topic on which to publish the client Will.
 --cafile : path to a file containing trusted CA certificates to enable encrypted
            certificate based communication.
 --capath : path to a directory containing trusted CA certificates to enable encrypted
 --cert : client certificate for authentication, if required by server.
 --key : client private key for authentication, if required by server.
 --ciphers : openssl compatible list of TLS ciphers to support.
 --tls-version : TLS protocol version, can be one of tlsv1.2 tlsv1.1 or tlsv1.
                 Defaults to tlsv1.2 if available.
 --insecure : do not check that the server certificate hostname matches the remote
              hostname. Using this option means that you cannot be sure that the
              remote host is the server you wish to connect to and so is insecure.
              Do not use this option in a production environment.
 --psk : pre-shared-key in hexadecimal (no leading 0x) to enable TLS-PSK mode.
 --psk-identity : client identity string for TLS-PSK mode.
 --proxy : SOCKS5 proxy URL of the form:
           Only "none" and "username" authentication is supported.

See for more information.

Payload Format Indicator and Content Type