Initially created to be used with motors that communicate via the use of MQTT protocol.
The server acts as an observer after the motors connected to the given MQTT channel. The server sends requests to the MQTT channel to command or ask about the status of the motors. The motors (their Arduino-like boards) read the commands and act accordingly, also updating the server about the status.
The clients (that can connect over REST and Websockets) can log in with pin or cards. After login, they create a websocket connection that lasts as long as their token does. The server will drop websockets connections with expired token every 1 second. The clients connected on the websocket also receive updates about the connected motors. Over REST, they also can command motors.
The client for this server can be found at https://github.com/kottochii/MotorControlClient
The Arduino sketch can be found at https://github.com/kottochii/ArduinoMQTTServo/
- A running Postgres server where the tables will be stored
- libPQXX (>=7.10.0)
- A running MQTT server
- MosquittoPP (particularly the client library)
- boost::property_tree for parsing the configuration file
- C++23
- CrowCpp
Once you have all the preinstalled prerequisites, make should take care of the basic compilation of the software. Two options are accepted:
CXX- the path to the C++ compilerBUILD_FLAGS- the flags passed to the compiler, if any required
In ./sql/motor_server.sql, there is a copy of the database structure that should be used with the software. Keep in mind that the user or the group that owns all the tables should be created. Owned by motor_server by default.
The configuration file should be located in /etc/motor_server/config.json. This is set by CONFIG_FILE macro in /app/main.cpp. If it is not readable or does not have any of the required parameters, the server will refuse to start.
host - host of the MQTT server
port - port of MQTT server
topic - topic at which MQTT server is trying to communicate with other devices
connection_string - string describing the connection initialiser of the PQXX server
For each motor, there should be a configuration for a single motor. At this point only one type is available, so this is mostly a list of the motors
port - host on which to run the HTTP server
ssl_cert - path to the SSL certificate to run HTTPS server
ssl_key - path to the SSL key to run HTTPS server
- there is no stable interface for finding the changes in motors' state -> cannot send updates; instead the status is sent every n seconds (fix by changing the logic of the DB access)