Repo to hold code for CS7NS6 Group F Project

• Python >= 3.6
• virtualenv
• Docker (optional, recommended)
• Docker-compose (optional, recommended)

If you are unable to use virtualenv to create a Python virtual environment for any reason, the requirements for the application are specified in requirements.txt.

The application's code is contained within the ./booking folder:

• File app.py is the main application code.
• File views.py contain the various handlers for HTTP responses within the application.
• File operation.py contains code related to database operations shared across both the frontend application and the Raft middleware.
• Filesraft-*.py contains code related to the Raft middleware.

Some other files (ipc.py, multicast.py, models.py) are legacy code and no longer required, but are included for reference.

The below commands will set up a new Python virtual environment and install the required packages:

virtualenv .venv
source .venv/bin/activate
pip install -r requirements.txt

It is recommended to use docker-compose to run this project.

To run the default setup for the application, simply run:

docker-compose -f docker-compose.yml up --build

This will perform the following steps:

• Build the cs7ns6groupf container from ./Dockerfile
• Create 3 instances of the cs7ns6groupf container: peer0, peer1, and peer2, each using different local files for the raft database and SQLite databse.

This will run forever until manually stopped with Control-C.

Files ./demo1.sh and ./demo2.sh each perform the following:

• Stand up a cluster of the application using docker-compose -f docker-compose.demoN.yml up --build
• Perform a number of actions on the cluster
• Query various endpoints of the cluster and display the output.

Note: to ensure a clean environment, you may need to remove all of the local data in between demoes. To do this, Run: sudo rm -f data/*

The file ./Dockerfile contains directives to build the cs7ns6groupf container with all the dependencies for the application included. It can be built on its own with the command:

docker build -t cs7ns6groupf:latest .

If you are unable to run Docker for whatever reason, you can instead run the code directly, which requires some initial setup. To run one instance of the application, first double-check you have performed the above virtualenv setup.

Then, run the following command, substituting where appropriate:

• DB_PATH: path to the node's SQLite database
• RAFT_STATE_PATH: path to the node's Raft persistent state
• SELF_ID: node identifier (positive integer)
• SELF: the node identifier, hostname, and port for Raft, separated by a colon. Example: 0:localhost:9000.
• PEERS: the peers in the node's cluster, specified in the same format as above.

Full example invocation:

DB_PATH=./data/0.db RAFT_STATE_PATH=./data/0.json SELF_ID=0 SELF=0:localhost:9000 PEERS='1:localhost:9001 2:localhost:9002' python ./app.py

Repeat this command multiple times to bring up multiple instances of the application.