1. Vagrantfile

   In the project root directory, create a Vagrantfile with the following content:

   Vagrant.configure("2") do |config|
     # Base box
     config.vm.box = "geerlingguy/ubuntu2004"
   
     # Network configuration
     config.vm.network "forwarded_port", guest: 3000, host: 3000
     config.vm.network "forwarded_port", guest: 5000, host: 5000
     config.vm.network "forwarded_port", guest: 27017, host: 27017
   
     # VM resources
     config.vm.provider "virtualbox" do |vb|
       vb.memory = "2048"
       vb.cpus = 2
     end
   
     # Sync the current directory with the VM
     config.vm.synced_folder ".", "/vagrant"
   
     # Provision the VM with Ansible
     config.vm.provision "ansible" do |ansible|
       ansible.playbook = "playbook.yml"
     end
   end

   This Vagrantfile sets up a Ubuntu 20.04 VM with Docker, Docker Compose, and forwards the necessary ports for the frontend, backend, and MongoDB.

2. Ansible Playbook

   Create an ansible/playbook.yml with tasks to set up Docker and the application:

   ---
   - hosts: all
     become: yes
   
     tasks:
       - name: Update APT package index
         apt:
           update_cache: yes
   
       - name: Install required packages
         apt:
           name:
             - apt-transport-https
             - ca-certificates
             - curl
             - software-properties-common
           state: present
   
       - name: Add Docker's official GPG key
         apt_key:
           url: https://download.docker.com/linux/ubuntu/gpg
           state: present
   
       - name: Add Docker's APT repository
         apt_repository:
           repo: deb [arch=amd64] https://download.docker.com/linux/ubuntu focal stable
           state: present
   
       - name: Install Docker
         apt:
           name: docker-ce
           state: present
   
       - name: Install Docker Compose
         apt:
           name: docker-compose
           state: present
   
       - name: Add vagrant user to the docker group
         user:
           name: vagrant
           groups: docker
           append: yes
   
       - name: Copy docker-compose.yml to VM
         copy:
           src: /vagrant/docker-compose.yml
           dest: /home/vagrant/docker-compose.yml
   
       - name: Run Docker Compose
         shell: docker-compose up -d
         args:
           chdir: /home/vagrant

   This playbook installs Docker, Docker Compose, and runs the application using docker-compose.

1. Start the Vagrant Environment

   To start the Vagrant environment, run the following command in the project root directory:

   vagrant up

   This command will create and configure the VM based on the Vagrantfile and Ansible playbook.

2. Access the VM

   SSH into the VM with:

   vagrant ssh

3. Check Running Containers

   Once inside the VM, you can verify the running Docker containers:

   docker ps

   This command should list the frontend, backend, and MongoDB containers.

4. Stop the Vagrant Environment

   To stop the Vagrant VM, use the following command:

   vagrant halt

5. Destroy the Vagrant Environment

   If you need to destroy the VM and start fresh, use:

   vagrant destroy

By using Vagrant, you can easily set up a development environment that mimics the production setup. This ensures consistency and helps in testing the application locally. The combination of Vagrant and Docker provides a robust solution for development and testing.