Pheromon

Overview

Pheromon is a open innovation project to deploy, administrate and harvest data from a swarm of sensors. It has been developed in the scope of project 6element dedicated to waste optimisation, and is now in production on the projet vamos.

Use our open API, you can have a look at the dedicated wiki.

Pheromon communicates with sensors over TCP using MQTT protocol. The MQTT broker dispatches the messages depending on the publish/subscribe status of various clients on various subjects. For example, a meteorological sensor will publish on the topics rain and temperature while a sensor measuring peoples fluxes will publish on wifidevices and bluetoothdevices. Meanwhile, the admin interface can publish to all sensors on the all topic, or to one particular sensor on mySensorId topic.

All the messages are persisted in a database that can be queried by a API able to answer queries like "give me all mesaurements of sensor X since Y".

Clients

Two clients are available for now.

The Dashboard is useful to visualize the measurements on a map.

You can also administrate your sensors with the Admin.

More on those clients later.

Quick start :

• clone the repository :

git clone git@github.com:anthill/pheromon.git
cd pheromon

• Copy / Create the files PRIVATE/*.json

• Install dependencies

npm install

In dev

Use this for development.

npm run dev

Use npm run stop-dev to stop.

In prod

Use this for production.

npm run prod // launch the service

Database

• Initialisation If you run a service without an initialized db, you need to

node database/management/init-db.js

• Backups and restore : At anytime you can backup the db using

node database/management/backup.js > backups/test.sql

or restore an previous db with

node database/management/restore.js backups/test.sql

you can also use a gziped file (comming from the automated backup for example).

MQTT

MQTT is the communication protocol between the server and the sensors.

Elements

The communication protocol is composed of 3 elements:

• broker: authenticates clients and relays messages
• sensor: client
• maestro: client, on the kerrigan server

Available Topics up to now:

From sensor to maestro:

• init/mySensorSimId, when sensor needs to initialize. There is no content.
• status/mySensorSimId/type, when a sensor status updates. The content is a string describing the actual status.
• measurement/mySensorSimId/type, when a measurement is sent from sensor. The content is an array of measurements.
• cmdResult/mySensorSimId, when a sensor processed a command sent from maestro. The content is a string describing the output of the command.

From maestro to sensor:

• mySensorSimId, when maestro sends command to sensor. The content is a string of the command.
• all, when maestro sends command to all registered sensors. The content is a string of the command.

Initialization sequence

We don't want sensors to have a manually hard-coded id (for deployment's simplicity) so we use mac addresses of devices:

Sequence

• [sensor] when powering up, sensor tries to connect to MQTT broker with authentification token.
• [broker] authenticates sensor.
• [sensor] when authenticated, sensor subscribes to mySensorSimId and all topics, then sends an empty message on init/mySensorSimId topic.
• [maestro] receives message, checks mySensorSimId in DB, creates Sensor if needed, and sends back [init, parameters] on simId topic.
• [sensor] receives message, initializes its parameters and routines.

Status update sequence

Each time the sensor's status changes, a message is sent to the maestro to update the DB and react accordingly depending on the situation. Status can be of 3 types:

• client: state of communication between sensor and kerrigan server
• signal: power of signal between sensor and kerrigan server
• wifi: wifi monitoring state of sensor
• blue: bluetooth monitoring state of sensor

Sequence

• [somewhere] something happens that changes the sensor type status to newStatus.
• [sensor] sends newStatus on status/mySensorSimId/type topic.
• [maestro] receives message, check mySensorSimId in DB, creates Sensor if needed, and updates sensor in DB.

Measurement push sequence

By default, sensor has measurement capabilities (for wifi and bluetooth). Every n minutes, sensor send measurements to kerrigan server to be recorded in DB.

Sequence

• [time passing] n minutes has passed since last measurement on measurementType.
• [sensor] wraps collected information into measurementContent and sends measurementContent on measurement/mySensorSimId/measurementType topic.
• [maestro] receives message, check mySensorSimId in DB, creates Sensor if needed, and then creates Measurement in DB.

Command sending sequence

You can send commands to the sensors.

Sequence

• [some admin client] sends a command to [mySensorSimId] through socketIO.
• [maestro] receives command from client, and forwards it to the corresponding sensors through MQTT.
• [sensor] receives message, execute command, and sends back the result of the command on the topic cmdResult/mySensorSimId
• [maestro] receives message, check mySensorSimId in DB, creates Sensor if needed, and then updates Sensor in DB.

Unitary tests

You can run Pheromon tests in a dedicated docker.

You can use

npm run test

Prepare the server and docker for the updater

• Create a user

sudo useradd -m sensorSSH;
sudo passwd sensorSSH;

• Create ssh keys for the user

su sensorSSH -c 'ssh-keygen -t rsa -b 4096';

• Add the sensor public key to the authorized_keys and vice-versa

• Add group docker to the user

sudo usermod -G docker sensorSSH;

• Add theses lines to /etc/ssh/sshd_config

AllowTcpForwarding yes
GatewayPorts yes

• Disable the user (chrooting it would be great)

sudo usermod -s /usr/sbin/nologin sensorSSH;

add "ip": ... in pheromon secret.json where kerrigan is the name of the host in .ssh/config

PRIVATE files

There are 2 PRIVATE files:

• secret.json: this file is very sensitive. Leaking it would potentially allow people to access your db, server, sensors, etc... It should not be required in non protected clients. Here, the only client that requires it is Admin, whose access is protected by html_token.

{
    "server_ip": ..., // your server ip, used by the sensor updater
    "html_token": ..., // token you should use to protect the access to your Admin client or database API
    "mqtt_user": ..., // username for mqtt
    "mqtt_token": ..., // MQTT for the broker to authenticate sensor
    "cmd_token": ... // token to allow cmd sending to sensor
}

server_ip is used in api/maestro.js.

html_token is used in api/api.js and api/routes.js.

cmd_token is used in api/maestro.js and api/clients/Admin/src/main.js.

• mapbox.json : this file is not very sensitive. It only contains mapbox infos

{
    "token": ..., // token for your mapbox account
    "map_id": ..., // id of your map background,
    "center": [16.1496297,-61.39705]
}

Both mapbox.json fields are used in api/clients/Dashboard/src/main.js.

Licence MIT

Contribute :

• Clone the repository.

• Create a new branch to work in.

• Make a pull request explaining why and what you changed.