An MQTT protocol based Chat-Server/Chat-System using Mosquitto Broker, tornado as web server, sockjs in client(browser) side javascript library, sockjs-tornado as sockjs implementation on server side and paho-mqtt (mqtt python client).

Link : http://mosquittochat.readthedocs.io/en/latest/

Link : https://pypi.python.org/pypi/mosquittoChat

Author

Anirban Roy Das

Email

[email protected]

Copyright(C)

2017, Anirban Roy Das <[email protected]>

Check mosquittoChat/LICENSE file for full Copyright notice.

mosquittochat is an MQTT protocol based simple Chat Server which can be set up locally to chat in your LAN. It supports both Public Chat among all participants connected simultaneously at a particular time and also Private Chat betweent those individual participants.

It uses the MQTT protocol to implement the real time message passing system. MQTT is implemented in many languages and in many softwares, one of such is Mosquitto , which is a message broker implementing the MQTT protocol.

The connection is created using the sockjs protocol. SockJS is implemented in many languages, primarily in Javascript to talk to the servers in real time, which tries to create a duplex bi-directional connection between the Client(browser) and the Server. Ther server should also implement the sockjs protocol. Thus using the sockjs-tornado library which exposes the sockjs protocol in Tornado server.

It first tries to create a Websocket connection, and if it fails then it fallbacks to other transport mechanisms, such as Ajax, long polling, etc. After the connection is established, the tornado server*(sockjs-tornado)* connects to Mosquitto via MQTT protocol using the MQTT Python Client Library, paho-mqtt.

Thus the connection is web-browser to tornado to mosquitto and vice versa.

sockjs-client

Advanced Websocket Javascript Client

Tornado

Async Python Web Library + Web Server

sockjs-tornado

SockJS websocket server implementation for Tornado

MQTT

Machine-to-Machine (M2M)/"Internet of Things" connectivity protocol

paho-mqtt

MQTT Python Client Library

Mosquitto

A Message Broker implementing MQTT in C

pytest

Python testing library and test runner with awesome test discobery

pytest-flask

Pytest plugin for flask apps, to test fask apps using pytest library.

Uber's Test-Double

Test Double library for python, a good alternative to the mock library

Jenkins (Optional)

A Self-hosted CI server

Travis-CI (Optional)

A hosted CI server free for open-source projecs

Docker

A containerization tool for better devops

• Public chat
• Shows who joined and who left
• Shows list of users online/offline
• Show last seen of offline features
• Shows who is typing and who is not - typing indicator
• Shows number of people online in public chat
• Join/Leave chat room features
• Microservice
• Testing using Docker and Docker Compose
• CI servers like Jenkins, Travis-CI

There are two types of Installation. One using rabbitChat as a binary by installaing from pip and running the application in the local machine directly. Another method is running the application from Docker. Hence another set of installation steps for the Docker use case.

To safegurad secret and confidential data leakage via your git commits to public github repo, check git-secrets.

This git secrets project helps in preventing secrete leakage by mistake.

1. Docker
2. Make (Makefile)

See, there are so many technologies used mentioned in the tech specs and yet the dependencies are just two. This is the power of Docker.

• Step 1 - Install Docker

  Follow my another github project, where everything related to DevOps and scripts are mentioned along with setting up a development environemt to use Docker is mentioned.

  • Project: https://github.com/anirbanroydas/DevOps

  • Go to setup directory and follow the setup instructions for your own platform, linux/macos

• Step 2 - Install Make :

  # (Mac Os)
  $ brew install automake
  
  # (Ubuntu)
  $ sudo apt-get update
  $ sudo apt-get install make

• Step 3 - Install Dependencies

  Install the following dependencies on your local development machine which will be used in various scripts.

  1. openssl
  2. ssh-keygen
  3. openssh

1. python 2.7+
2. tornado
3. sockjs-tornado
4. sockjs-client
5. paho-mqtt
6. mosquitto

$ pip install mosquittoChat

If above dependencies do not get installed by the above command, then use the below steps to install them one by one.

Step 1 - Install pip

Follow the below methods for installing pip. One of them may help you to install pip in your system.

• Method 1 - https://pip.pypa.io/en/stable/installing/
• Method 2 - http://ask.xmodulo.com/install-pip-linux.html
• Method 3 - If you installed python on MAC OS X via brew install python, then pip is already installed along with python.

Step 2 - Install tornado :

$ pip install tornado

Step 3 - Install sockjs-tornado :

$ pip install sockjs-tornado

Step 4 - Install paho-mqtt :

$ pip install paho-mqtt

Step 5 - Install Mosquitto

• For Mac Users

  1. Brew Install Mosquitto :

  $ brew install mosquitto

  2. Configure mosquitto, by modifying the file at /usr/local/etc/mosquitto/mosquitto.conf.

• For Ubuntu/Linux Users

  1. Enable mosquitto repository (optional)

     First Try directly, if it doesn't work, then follow this step and continue after this.:

     $ sudo apt-add-repository ppa:mosquitto-dev/mosquitto-ppa

  2. Update the sources with our new addition from above :

  $ apt-get update

  3. And finally, download and install Mosquitto :

  $ sudo apt-get install mosquitto

  4. Configure mosquitto, by modifying the file at /usr/local/etc/mosquitto/mosquitto.conf.

If you are using the project in a CI setup (like travis, jenkins), then, on every push to github, you can set up your travis build or jenkins pipeline. Travis will use the .travis.yml file and Jenknis will use the Jenkinsfile to do their jobs. Now, in case you are using Travis, then run the Travis specific setup commands and for Jenkins run the Jenkins specific setup commands first. You can also use both to compare between there performance.

The setup keys read the values from a .env file which has all the environment variables exported. But you will notice an example env file and not a .env file. Make sure to copy the env file to .env and change/modify the actual variables with your real values.

The .env files are not commited to git since they are mentioned in the .gitignore file to prevent any leakage of confidential data.

After you run the setup commands, you will be presented with a number of secure keys. Copy those to your config files before proceeding.

NOTE: This is a one time setup. NOTE: Check the setup scripts inside the scripts/ directory to understand what are the environment variables whose encrypted keys are provided. NOTE: Don't forget to Copy the secure keys to your .travis.yml or Jenkinsfile

NOTE: If you don't want to do the copy of env to .env file and change the variable values in .env with your real values then you can just edit the travis-setup.sh or jenknis-setup.sh script and update the values their directly. The scripts are in the scripts/ project level directory.

IMPORTANT: You have to run the travis-setup.sh script or the jenkins-setup.sh script in your local machine before deploying to remote server.

These steps will encrypt your environment variables to secure your confidential data like api keys, docker based keys, deploy specific keys. :

$ make travis-setup

These steps will encrypt your environment variables to secure your confidential data like api keys, docker based keys, deploy specific keys. :

$ make jenkins-setup

There are two types of Usage. One using rabbitChat as a binary by installaing from pip and running the application in the local machine directly. Another method is running the application from Docker. Hence another set of usage steps for the Docker use case.

After having installed the above dependencies, and ran the Optional (If not using any CI Server) or Required (If using any CI Server) CI Setup Step, then just run the following commands to use it:

You can run and test the app in your local development machine or you can run and test directly in a remote machine. You can also run and test in a production environment.

The below commands will start everythin in development environment. To start in a production environment, suffix -prod to every make command.

For example, if the normal command is make start, then for production environment, use make start-prod. Do this modification to each command you want to run in production environment.

Exceptions: You cannot use the above method for test commands, test commands are same for every environment. Also the make system-prune command is standalone with no production specific variation (Remains same in all environments).

• Start Applcation :

  $ make clean
  $ make build
  $ make start
  
  # OR
  
  $ docker-compose up -d

• Stop Application :

  $ make stop
  
  # OR
  
  $ docker-compose stop

• Remove and Clean Application :

  $ make clean
  
  # OR
  
  $ docker-compose rm --force -v
  $ echo "y" | docker system prune

• Clean System :

  $ make system-prune
  
  # OR
  
  $ echo "y" | docker system prune

• To check the whole application Logs :

  $ make check-logs
  
  # OR
  
  $ docker-compose logs --follow --tail=10

• To check just the python app's logs :

  $ make check-logs-app
  
  # OR
  
  $ docker-compose logs --follow --tail=10 identidock

After having installed mosquittoChat, just run the following commands to use it:

• Mosquitto Server

  1. For Mac Users :

  # start normally
  $ mosquitto -c /usr/local/etc/mosquitto/mosquitto.conf
  
  # If you want to run in background
  $ mosquitto -c /usr/local/etc/mosquitto/mosquitto.conf -d 
  
  # start using brew services (doesn't work with tmux, athough there is a fix, mentioned in one of the pull requests and issues)
  $ brew services start mosquitto

  2. For Ubuntu/LInux Users :

  # start normally
  $ mosquitto -c /usr/local/etc/mosquitto/mosquitto.conf
  
  # If you want to run in background
  $ mosquitto -c /usr/local/etc/mosquitto/mosquitto.conf -d 
  
  # To start using service
  $ sudo service mosquitto start
  
  # To stop using service
  $ sudo service mosquitto stop
  
  # To restart using service
  $ sudo service mosquitto restart
  
  # To check the status
  $ service mosquitto status

• Start mosquittochat Applcation :

  $ mosquittoChat [options]

  • Options

    --port

    Port number where the chat server will start

  • Example :

    $ mosquittoChat --port=9191

• Stop mosquittoChat Server

  Click Ctrl+C to stop the server.

NOTE: Testing is only done using the Docker Method. anyway, it should not matter whether you run your application using the Docker Method or the Standalone Method. Testing is independent of it.

Now, testing is the main deal of the project. You can test in many ways, namely, using make commands as mentioned in the below commands, which automates everything and you don't have to know anything else, like what test library or framework is being used, how the tests are happening, either directly or via docker containers, or may be different virtual environments using tox. Nothing is required to be known.

On the other hand if you want fine control over the tests, then you can run them directly, either by using pytest commands, or via tox commands to run them in different python environments or by using docker-compose commands to run differetn tests.

But running the make commands is lawasy the go to strategy and reccomended approach for this project.

NOTE: Tox can be used directly, where docker containers will not be used. Although we can try to run tox inside our test contianers that we are using for running the tests using the make commands, but then we would have to change the Dockerfile and install all the python dependencies like python2.7, python3.x and then run tox commands from inside the docker containers which then run the pytest commands which we run now to perform our tests inside the current test containers.

CAVEAT: The only caveat of using the make commands directly and not using tox is we are only testing the project in a single python environment, nameley python 3.6.

• To Test everything :

  $ make test

  Any Other method without using make will involve writing a lot of commands. So use the make command preferrably

• To perform Unit Tests :

  $ make test-unit

• To perform Component Tests :

  $ make test-component

• To perform Contract Tests :

  $ make test-contract

• To perform Integration Tests :

  $ make test-integration

• To perform End To End (e2e) or System or UI Acceptance or Functional Tests :

  $ make test-e2e
  
  # OR
  
  $ make test-system
  
  # OR  
  
  $ make test-ui-acceptance
  
  # OR
  
  $ make test-functional

1. Add Private Chat functionality.
2. Manage Presence Management, sent, delivered acknowledgements.
3. Message Persistence and delivery of messages to offline clinets.
4. Add Blog post regarding this topic.