T8 Project

status: the development of the project has stopped for now and there are no plans to continue it in the future

Dentistimo Middleware

This is the middleware of group eights Dentistimo system. Dentistimo is a distributed system which allows users to book dentist appointments in the Gothenburg region and allows for more clinics to be added in the future. This repository contains the middleware which is responsible for allowing other components of the system to communicate with one another. This is done through the use of MQTT and WebSocket. Messages are sent in the JSON format (id, request, url, data, authenticated). The middleware component provides the following functionalities:

• receive mqtt messages through a websocket connection
• parse mqtt messages
• send mqtt messages through a websocket connection
• create new mqtt topics
• subscribe and publish to mqtt topics
• distinguish between authenticated and unauthenticated requests

Installation

In order to run the component you need to have the project on your computer, node.js installed and mosquito installed.

• The first step is installing node.js, what version you should download depends on your operating system (this guide will show the process for windows, if you're using mac or linux you can check out this guide which explains that process as well)
  • Double click the .msi file in order to begin the installation process

   

Click on next.

 

select the destination where you want to install Node.js. If you don’t want to change the directory, go with the Windows default location and click the Next button again.

 

If you want a standard installation with the Node.js default features, click the Next button. Otherwise, you can select your specific elements from the icons in the tree before clicking Next.

 

Node.js offers you options to install tools for native modules. If you’re interested in these, click the checkbox to mark your preferences, or click Next to move forward with the default.

 

Click install, this can take a couple of minutes

 

• Once you have finished the installation you can verify it by opening the CMD and typing:

node --version

• You can also check npm by typing:

npm --version

If node has been correctly installed you should see the version name in the CMD prompt

 

• The second step is to install the mosquitto broker, once again this will be different depending on your OS. This guide will show the process for windows but you can check out the Mac or Linux guides if you are using a different operating system.
  • Double click the install script

   

Note the dependencies screen which tells you what additional files are required. The screen is not very clear.

 

Select components check service to install as a service if you want mosquitto to start automatically when windows starts.

 

Choose a location and click install, it defaults to c:\program files\mosquitto.

 

• Once you have finished installing you can start the mosquitto broker by going to the location where you installed mqtt, opening the CMD and typing:

mosquitto

• The next step is to download the project .zip file or pull the project with git, if you have that installed.

• Extract the project files from the .zip and put them in a place you can easily find, example:

  C:\Users\name\Desktop\t8-project-main

• open the CMD and go to the directory where you put the files. This can be done by typing cd + the file path. If I put my files in C:\Users\name\Desktop\t8-project-main I would type:

  cd C:\Users\name\Desktop\t8-project-main

• Type:

  npm install

• Once all dependencies have been installed, type the command

  npm start

If everything is installed correctly and running as it should you should see something like this

Usage

The middleware can only really be used for one purpose and that is lightweight communication through mqtt. By creating something similar to the component on our client side which sends mqtt request in the required format and a component which can receive messages, you can easily send messages between those using the middleware. The format of the messages can also be changed to suit the needs of the system and messages can always be checked when passing through the middleware if need be. This does however require changing the source code.

Support

If you encounter any issue related to the middleware we recommend first checking that both node.js and mqtt are working correctly as they are the most likely point of failure. Running the tests can also be useful for identifying issues in the system. If neither of those work you are free to contact us at this email.

Contributing

We are for the moment not open to contributions.

Authors and acknowledgment

@coetzer

@ayvazian

@yasaminf

@dunvald

@aminmah

@samcenko

@shatskyi

License