MQCLIENTSPAWNER

A small app to create a batch of dummy mqtt clients that will switch on and off and publish random messages to mqtt over a period of time.

Usage

Run the service and it will create N dummy clients.

These clients will publish to a topic of your choice. You can set the average expected messages over the duration of the lifetime of a client, and when a client is expected to peak its message flow.

Clients will connect and disconnect during their lifecycle based on the connectivity parameter.

Each client will be created with its own generated ClientID property.

Each client is spawned in its own goroutine, which should allow for running a lot of little clients concurrently.

This app can be used to load-test or explore failure points in a mqtt setup.

Install & run

You can run standalone or from a docker container.

You configure the service using command line flags or environment variables.

Env	Flag	Type	Default	Description
MQTT_BROKER	mqtt_broker	string	tcp://mqtt:1883	MQTT broker address ( note websockets supported if you use ws:// or wss:// protocol)
MQTT_TOPIC	mqtt_topic	string	client/{{.ClientID}}	Go format string to represent topic to publish to
MQTT_USER	mqtt_user	string	""	Username for mqtt
MQTT_PASSWORD	mqtt_password	string	""	Password for mqtt
NUM_CLIENTS	num_clients	int	10	Number of clients to create
DURATION	duration	go duration string	10m	How long to run the app for
START_PEAK	start_peak	go duration string	1m	When to start peak period
END_PEAK	end_peak	go duration string	9m	When to end peak period
AVG_MESSAGES	avg_messages	int	80	Average number of messages to send per client over the course of duration
PEAK_DISTRIBUTION	peak_distribution	float	0.8	Proportion of messages that should be sent during peak
CONNECTION_STRENGTH	connection_strength	float	0.9	Proportion of duration that clients should spend connected. Clients will connect and disconnect at random intervals

Standalone

Go get and install

go get -u github.com/woosteln/mqclientspawner

Run

mqclientspawner --mqtt_broker=tcp://localhost:1083 --mqtt_topic=device/{{.ClientID}}

Docker

Use the prebuilt docker image.

cmd line

docker run -d -e MQTT_BROKER=tcp://mqtt:1883 -MQTT_TOPIC=device/{{.ClientID}} woosteln/mqclientspawner:latest

docker compose

An example stack which gets a mqtt broker and client spawner up and running.

We attach cadvisor so you can check cpu and mem usage of the containers.

version: "3"
services:

    mqtt:
        image: emq:latest
        ports:
            - 18083:18083
            - 1883:1883

    mqclientspawner:
        image: woosteln/mqclientspawner:latest
        depends_on:
            - mqtt
        environment:
            MQTT_BROKER: tcp://mqtt:1883
            MQTT_TOPIC: device/{{.ClientID}}
            MQTT_USER: clientspwaner
            NUM_CLIENTS: 500
            DURATION: 10m
            START_PEAK: 1m
            END_PEAK: 9m
            AVG_MESSAGES: 100
            PEAK_DISTRIBUTION: 0.8
            CONNECTION_STRENGTH: 0.8

    cadvisor:
        image: google/cadvisor:latest
        ports:
            - 8080:8080
        volumes:
            - /var/run:/var/run:rw
            - /sys:/sys:ro
            - /var/lib/docker/:/var/lib/docker:ro