mosquitto_pub (1)


NAME

mosquitto_pub - an mqtt version 3.1 client for publishing simple messages

SYNOPSIS

mosquitto_pub [-d] [-h hostname] [-i client_id] [-I client id prefix] [-p port number] [-q message QoS] [--quiet] [-r] { -f file | -l | -m message | -n | -s} [ -u username [-P password] ] [ --will-topic topic [--will-payload payload] [--will-qos qos] [--will-retain] ] -t message-topic

DESCRIPTION

mosquitto_pub is a simple mqtt version 3.1 client that will publish a single message on a topic and exit.

OPTIONS

-d, --debug
Enable debug messages.
-f, --file
Send the contents of a file as the message.
-h, --host
Specify the host to connect to. Defaults to localhost.
-i, --id
The id to use for this client. If not given, defaults to mosquitto_pub_ appended with the process id of the client. Cannot be used at the same time as the --id-prefix argument.
-I, --id-prefix
Provide a prefix that the client id will be built from by appending the process id of the client. This is useful where the broker is using the clientid_prefixes option. Cannot be used at the same time as the --id argument.
-l, --stdin-line
Send messages read from stdin, splitting separate lines into separate messages. Note that blank lines won't be sent.
-m, --message
Send a single message from the command line.
-n, --null-message
Send a null (zero length) message.
-p, --port
Connect to the port specified instead of the default 1883.
-P, --pw
Provide a password to be used for authenticating with the broker. Using this argument without also specifying a username is invalid. This requires a broker that supports MQTT v3.1. See also the --username option.
-q, --qos
Specify the quality of service to use for the message, from 0, 1 and 2. Defaults to 0.
--quiet
If this argument is given, no runtime errors will be printed. This excludes any error messages given in case of invalid user input (e.g. using --port without a port).
-r, --retain
If retain is given, the message will be retained as a "last know good" value on the broker. See mqtt(7) for more information.
-s, --stdin-file
Send a message read from stdin, sending the entire content as a single message.
-t, --topic
The mqtt topic on which to publish the message. See mqtt(7) for more information on mqtt topics.
-u, --username
Provide a username to be used for authenticating with the broker. This requires a broker that supports MQTT v3.1. See also the --pw argument.
--will-payload
Specify a message that will be stored by the broker and sent out if this client disconnects unexpectedly. This must be used in conjunction with --will-topic.
--will-qos
The QoS to use for the Will. Defaults to 0. This must be used in conjunction with --will-topic.
--will-retain
If given, if the client disconnects unexpectedly the message sent out will be treated as a retained message. This must be used in conjunction with --will-topic.
--will-topic
The topic on which to send a Will, in the event that the client disconnects unexpectedly.

WILLS

mosquitto_sub can register a message with the broker that will be sent out if it disconnects unexpectedly. See mqtt(7) for more information.

The minimum requirement for this is to use --will-topic to specify which topic the will should be sent out on. This will result in a non-retained, zero length message with QoS 0.

Use the --will-retain, --will-payload and --will-qos arguments to modify the other will parameters.

EXAMPLES

Publish temperature information to localhost with QoS 1:
mosquitto_pub -t sensors/temperature -m 32 -q 1

Publish timestamp and temperature information to a remote host on a non-standard port and QoS 0:

mosquitto_pub -h 192.168.1.1 -p 1885 -t sensors/temperature -m "1266193804 32"

Publish light switch status. Message is set to retained because there may be a long period of time between light switch events:

mosquitto_pub -r -t switches/kitchen_lights/status -m "on"

Send the contents of a file in two ways:

mosquitto_pub -t my/topic -f ./data
mosquitto_pub -t my/topic -s < ./data

Send parsed electricity usage data from a Current Cost meter, reading from stdin with one line/reading as one message:

read_cc128.pl | mosquitto_pub -t sensors/cc128 -l

BUGS

mosquitto_pub bug information can be found at http://launchpad.net/mosquitto

SEE ALSO

mqtt(7) mosquitto_sub(1) mosquitto(8) libmosquitto(3)

AUTHOR

Roger Light <roger@atchoo.org>