Provided by: mosquitto-clients_1.6.9-1_amd64 bug

NAME

       mosquitto_pub - an MQTT version 5/3.1.1/3.1 client for publishing simple messages

SYNOPSIS

       mosquitto_pub
                     {[-h hostname] [-p port-number] [-u username] [-P password] -t message-topic...
                     | -L URL} [-A bind-address] [-c] [-d] [-D command identifier value]
                     [-i client-id] [-I client-id-prefix] [-k keepalive-time] [-q message-QoS]
                     [--quiet] [-r] [--repeat count] [--repeat-delay seconds] [-S] {-f file | -l
                     | -m message | -n | -s}
                     [--will-topic topic [--will-payload payload] [--will-qos qos] [--will-retain]]
                     [[{--cafile file | --capath dir} [--cert file] [--key file] [--ciphers ciphers] [--tls-version version] [--tls-alpn protocol] [--tls-engine engine] [--keyform {pem | engine}] [--tls-engine-kpass-sha1 kpass-sha1] [--insecure]]
                     |
                     [--psk hex-key --psk-identity identity [--ciphers ciphers] [--tls-version version]]]
                     [--proxy socks-url] [-V protocol-version]

       mosquitto_pub [--help]

DESCRIPTION

       mosquitto_pub is a simple MQTT version 5/3.1.1 client that will publish a single message
       on a topic and exit.

ENCRYPTED CONNECTIONS

       mosquitto_pub supports TLS encrypted connections. It is strongly recommended that you use
       an encrypted connection for anything more than the most basic setup.

       To enable TLS connections when using x509 certificates, one of either --cafile or --capath
       must be provided as an option.

       To enable TLS connections when using TLS-PSK, you must use the --psk and the
       --psk-identity options.

OPTIONS

       The options below may be given on the command line, but may also be placed in a config
       file located at $XDG_CONFIG_HOME/mosquitto_pub or $HOME/.config/mosquitto_pub with one
       pair of -option value per line. The values in the config file will be used as defaults and
       can be overridden by using the command line. The exceptions to this are the message type
       options, of which only one can be specified. Note also that currently some options cannot
       be negated, e.g.  -S. Config file lines that have a # as the first character are treated
       as comments and not processed any further.

       -A
           Bind the outgoing connection to a local ip address/hostname. Use this argument if you
           need to restrict network communication to a particular interface.

       -c, --disable-clean-session
           Disable the 'clean session' flag. This means that all of the subscriptions for the
           client will be maintained after it disconnects, along with subsequent QoS 1 and QoS 2
           messages that arrive. When the client reconnects, it will receive all of the queued
           messages.

           If using this option, the client id must be set manually with --id

       --cafile
           Define the path to a file containing PEM encoded CA certificates that are trusted.
           Used to enable SSL communication.

           See also --capath

       --capath
           Define the path to a directory containing PEM encoded CA certificates that are
           trusted. Used to enable SSL communication.

           For --capath to work correctly, the certificate files must have ".crt" as the file
           ending and you must run "openssl rehash <path to capath>" each time you add/remove a
           certificate.

           See also --cafile

       --cert
           Define the path to a file containing a PEM encoded certificate for this client, if
           required by the server.

           See also --key.

       --ciphers
           An openssl compatible list of TLS ciphers to support in the client. See ciphers(1) for
           more information.

       -d, --debug
           Enable debug messages.

       -D, --property
           Use an MQTT v5 property with this publish. If you use this option, the client will be
           set to be an MQTT v5 client. This option has two forms:

           -D command identifier value

           -D command identifier name value

           command is the MQTT command/packet identifier and can be one of CONNECT, PUBLISH,
           PUBREL, DISCONNECT, AUTH, or WILL. The properties available for each command are
           listed in the Properties section.

           identifier is the name of the property to add. This is as described in the
           specification, but with '-' as a word separator. For example:
           payload-format-indicator. More details are in the Properties section.

           value is the value of the property to add, with a data type that is property specific.

           name is only used for the user-property property as the first of the two strings in
           the string pair. In that case, value is the second of the strings in the pair.

       -f, --file
           Send the contents of a file as the message.

       --help
           Display usage information.

       -h, --host
           Specify the host to connect to. Defaults to localhost.

       -i, --id
           The id to use for this client. If not given, a client id will be generated depending
           on the MQTT version being used. For v3.1.1/v3.1, the client generates a client id in
           the format mosq-XXXXXXXXXXXXXXXXXX, where the X are replaced with random alphanumeric
           characters. For v5.0, the client sends a zero length client id, and the server will
           generate a client id for the client.

           This option 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.

       --insecure
           When using certificate based encryption, this option disables verification of the
           server hostname in the server certificate. This can be useful when testing initial
           server configurations but makes it possible for a malicious third party to impersonate
           your server through DNS spoofing, for example. Use this option in testing only. If you
           need to resort to using this option in a production environment, your setup is at
           fault and there is no point using encryption.

       -k, --keepalive
           The number of seconds between sending PING commands to the broker for the purposes of
           informing it we are still connected and functioning. Defaults to 60 seconds.

       --key
           Define the path to a file containing a PEM encoded private key for this client, if
           required by the server.

           See also --cert.

       --keyform
           Specifies the type of private key in use when making TLS connections.. This can be
           "pem" or "engine". This parameter is useful when a TPM module is being used and the
           private key has been created with it. Defaults to "pem", which means normal private
           key files are used.

           See also --tls-engine.

       -L, --url
           Specify specify user, password, hostname, port and topic at once as a URL. The URL
           must be in the form: mqtt(s)://[username[:password]@]host[:port]/topic

           If the scheme is mqtt:// then the port defaults to 1883. If the scheme is mqtts://
           then the port defaults to 8883.

       -l, --stdin-line
           Send messages read from stdin, splitting separate lines into separate messages.

       -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. If not given, the default of 1883 for plain MQTT or
           8883 for MQTT over TLS will be used.

       -P, --pw
           Provide a password to be used for authenticating with the broker. Using this argument
           without also specifying a username is invalid when using MQTT v3.1 or v3.1.1. See also
           the --username option.

       --proxy
           Specify a SOCKS5 proxy to connect through. "None" and "username" authentication types
           are supported. The socks-url must be of the form
           socks5h://[username[:password]@]host[:port]. The protocol prefix socks5h means that
           hostnames are resolved by the proxy. The symbols %25, %3A and %40 are URL decoded into
           %, : and @ respectively, if present in the username or password.

           If username is not given, then no authentication is attempted. If the port is not
           given, then the default of 1080 is used.

           More SOCKS versions may be available in the future, depending on demand, and will use
           different protocol prefixes as described in curl(1).

       --psk
           Provide the hexadecimal (no leading 0x) pre-shared-key matching the one used on the
           broker to use TLS-PSK encryption support.  --psk-identity must also be provided to
           enable TLS-PSK.

       --psk-identity
           The client identity to use with TLS-PSK support. This may be used instead of a
           username if the broker is configured to do so.

       -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 known good" value on the
           broker. See mqtt(7) for more information.

       --repeat
           If the publish mode is-m, -f, or -s (i.e. the modes where only a single message is
           sent), then --repeat can be used to specify that the message will be published
           multiple times.

           See also --repeat-delay.

       --repeat-delay
           If using --repeat, then the default behaviour is to publish repeated messages as soon
           as the previous message is delivered. Use --repeat-delay to specify the number of
           seconds to wait after the previous message was delivered before publishing the next.
           Does not need to be an integer number of seconds.

           Note that there is no guarantee as to the actual interval between messages, this
           option simply defines the minimum time from delivery of one message to the start of
           the publish of the next.

       -s, --stdin-file
           Send a message read from stdin, sending the entire content as a single message.

       -S
           Use SRV lookups to determine which host to connect to. Performs lookups to
           _mqtt._tcp.<host> when used in conjunction with -h, otherwise uses _mqtt._tcp.<local
           dns domain>.

       -t, --topic
           The MQTT topic on which to publish the message. See mqtt(7) for more information on
           MQTT topics.

       --tls-alpn
           Provide a protocol to use when connecting to a broker that has multiple protocols
           available on a single port, e.g. MQTT and WebSockets.

       --tls-engine
           A valid openssl engine id. These can be listed with openssl engine command.

           See also --keyform.

       --tls-engine-kpass-sha1
           SHA1 of the private key password when using an TLS engine. Some TLS engines such as
           the TPM engine may require the use of a password in order to be accessed. This option
           allows a hex encoded SHA1 hash of the password to the engine directly, instead of the
           user being prompted for the password.

           See also --tls-engine.

       --tls-version
           Choose which TLS protocol version to use when communicating with the broker. Valid
           options are tlsv1.3, tlsv1.2 and tlsv1.1. The default value is tlsv1.2. Must match the
           protocol version used by the broker.

       -u, --username
           Provide a username to be used for authenticating with the broker. See also the --pw
           argument.

       -V, --protocol-version
           Specify which version of the MQTT protocol should be used when connecting to the
           rmeote broker. Can be 5, 311, 31, or the more verbose mqttv5, mqttv311, or mqttv31.
           Defaults to 311.

       --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.

PROPERTIES

       The -D / --property option allows adding properties to different stages of the
       mosquitto_pub run. The properties supported for each command are as follows:

   Connectauthentication-data (binary data - note treated as a string in mosquitto_pub)

       •   authentication-method (UTF-8 string pair)

       •   maximum-packet-size (32-bit unsigned integer)

       •   receive-maximum (16-bit unsigned integer)

       •   request-problem-information (8-bit unsigned integer)

       •   request-response-information (8-bit unsigned integer)

       •   session-expiry-interval (32-bit unsigned integer)

       •   topic-alias-maximum (16-bit unsigned integer)

       •   user-property (UTF-8 string pair)

   Publishcontent-type (UTF-8 string)

       •   correlation-data (binary data - note treated as a string in mosquitto_pub)

       •   message-expiry-interval (32-bit unsigned integer)

       •   payload-format-indicator (8-bit unsigned integer)

       •   response-topic (UTF-8 string)

       •   topic-alias (16-bit unsigned integer)

       •   user-property (UTF-8 string pair)

   Disconnectsession-expiry-interval (32-bit unsigned integer)

       •   user-property (UTF-8 string pair)

   Will propertiescontent-type (UTF-8 string)

       •   correlation-data (binary data - note treated as a string in mosquitto_pub)

       •   message-expiry-interval (32-bit unsigned integer)

       •   payload-format-indicator (8-bit unsigned integer)

       •   response-topic (UTF-8 string)

       •   user-property (UTF-8 string pair)

       •   will-delay-interval (32-bit unsigned integer)

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

FILES

       $XDG_CONFIG_HOME/mosquitto_pub, $HOME/.config/mosquitto_pub
           Configuration file for default options.

BUGS

       mosquitto bug information can be found at https://github.com/eclipse/mosquitto/issues

SEE ALSO

       mqtt(7), mosquitto_rr(1), mosquitto_sub(1), mosquitto(8), libmosquitto(3), mosquitto-
       tls(7)

AUTHOR

       Roger Light <roger@atchoo.org>