diff --git a/README.md b/README.md
index 69ea06bbc20e35cbee205142182cd52bb151cb70..f13803605bc74eb47a504c958318bcd273722b96 100644
--- a/README.md
+++ b/README.md
@@ -1,93 +1,203 @@
-# Docker Compose Example
+# Docker Container Basics: Understanding Bridge and Overlay Networks
+## Objectives
+- Learn the differences between **Bridge** and **Overlay** networks in Docker.
+- Understand how containers in different networks can communicate.
-## Getting started
+## Introduction to Docker Networks
-To make it easy for you to get started with GitLab, here's a list of recommended next steps.
+Docker networks allow containers to communicate with each other. There are different types of networks, but we'll focus on two:
-Already a pro? Just edit this README.md and make it your own. Want to make it easy? [Use the template at the bottom](#editing-this-readme)!
+1. **Bridge Network:** Works on a single Docker host (your computer or server). Containers in the same bridge network can communicate, while those in different bridge networks need some special setup to talk to each other.
-## Add your files
+2. **Overlay Network:** Designed for Docker Swarm, which allows containers on different physical or virtual machines to communicate as if they are on the same network.
-- [ ] [Create](https://docs.gitlab.com/ee/user/project/repository/web_editor.html#create-a-file) or [upload](https://docs.gitlab.com/ee/user/project/repository/web_editor.html#upload-a-file) files
-- [ ] [Add files using the command line](https://docs.gitlab.com/ee/gitlab-basics/add-file.html#add-a-file-using-the-command-line) or push an existing Git repository with the following command:
+### When to Use Each Network
-```
-cd existing_repo
-git remote add origin https://gitedu.hesge.ch/lsds/teaching/master/cloud/docker-compose-example.git
-git branch -M main
-git push -uf origin main
-```
-
-## Integrate with your tools
-
-- [ ] [Set up project integrations](https://gitedu.hesge.ch/lsds/teaching/master/cloud/docker-compose-example/-/settings/integrations)
-
-## Collaborate with your team
-
-- [ ] [Invite team members and collaborators](https://docs.gitlab.com/ee/user/project/members/)
-- [ ] [Create a new merge request](https://docs.gitlab.com/ee/user/project/merge_requests/creating_merge_requests.html)
-- [ ] [Automatically close issues from merge requests](https://docs.gitlab.com/ee/user/project/issues/managing_issues.html#closing-issues-automatically)
-- [ ] [Enable merge request approvals](https://docs.gitlab.com/ee/user/project/merge_requests/approvals/)
-- [ ] [Set auto-merge](https://docs.gitlab.com/ee/user/project/merge_requests/merge_when_pipeline_succeeds.html)
-
-## Test and Deploy
-
-Use the built-in continuous integration in GitLab.
-
-- [ ] [Get started with GitLab CI/CD](https://docs.gitlab.com/ee/ci/quick_start/index.html)
-- [ ] [Analyze your code for known vulnerabilities with Static Application Security Testing (SAST)](https://docs.gitlab.com/ee/user/application_security/sast/)
-- [ ] [Deploy to Kubernetes, Amazon EC2, or Amazon ECS using Auto Deploy](https://docs.gitlab.com/ee/topics/autodevops/requirements.html)
-- [ ] [Use pull-based deployments for improved Kubernetes management](https://docs.gitlab.com/ee/user/clusters/agent/)
-- [ ] [Set up protected environments](https://docs.gitlab.com/ee/ci/environments/protected_environments.html)
+- **Bridge Network:** Use this when all your containers are on the same machine.
+- **Overlay Network:** Use this when your containers are spread across multiple machines (in a Docker Swarm).
-***
+Now, let's look at some examples to make this clearer.
-# Editing this README
+## Example 1: Using a Bridge Network
-When you're ready to make this README your own, just edit this file and use the handy template below (or feel free to structure it however you want - this is just a starting point!). Thanks to [makeareadme.com](https://www.makeareadme.com/) for this template.
+In this example, we’ll set up a simple application with three containers: one RabbitMQ service and two other services (app1 and app2). We'll connect these services using two separate bridge networks.
-## Suggestions for a good README
+### Bridge Network Docker Compose File
-Every project is different, so consider which of these sections apply to yours. The sections used in the template are suggestions for most open source projects. Also keep in mind that while a README can be too long and detailed, too long is better than too short. If you think your README is too long, consider utilizing another form of documentation rather than cutting out information.
+Here’s the `docker-compose.yaml` file for setting up our containers:
-## Name
-Choose a self-explaining name for your project.
+```yaml
+version: '3.8'
-## Description
-Let people know what your project can do specifically. Provide context and add a link to any reference visitors might be unfamiliar with. A list of Features or a Background subsection can also be added here. If there are alternatives to your project, this is a good place to list differentiating factors.
+services:
+ rabbitmq:
+ image: rabbitmq:3-management
+ container_name: rabbitmq
+ ports:
+ - "5672:5672" # RabbitMQ default messaging port
+ - "15672:15672" # RabbitMQ management console
+ networks:
+ - app-network-1
+ - app-network-2
-## Badges
-On some READMEs, you may see small images that convey metadata, such as whether or not all the tests are passing for the project. You can use Shields to add some to your README. Many services also have instructions for adding a badge.
+ app1:
+ image: franciscomendonca/auto-messaging:1.0.1
+ restart: on-failure
+ environment:
+ - START_WITH_MESSAGE=true # Start by sending a message
+ - RABBITMQ_HOST=rabbitmq
+ depends_on:
+ - rabbitmq
+ networks:
+ - app-network-1
-## Visuals
-Depending on what you are making, it can be a good idea to include screenshots or even a video (you'll frequently see GIFs rather than actual videos). Tools like ttygif can help, but check out Asciinema for a more sophisticated method.
+ app2:
+ image: franciscomendonca/auto-messaging:1.0.1
+ container_name: app2
+ restart: on-failure
+ environment:
+ - START_WITH_MESSAGE=false # Wait for a message before responding
+ - RABBITMQ_HOST=rabbitmq
+ depends_on:
+ - rabbitmq
+ networks:
+ - app-network-2
-## Installation
-Within a particular ecosystem, there may be a common way of installing things, such as using Yarn, NuGet, or Homebrew. However, consider the possibility that whoever is reading your README is a novice and would like more guidance. Listing specific steps helps remove ambiguity and gets people to using your project as quickly as possible. If it only runs in a specific context like a particular programming language version or operating system or has dependencies that have to be installed manually, also add a Requirements subsection.
-
-## Usage
-Use examples liberally, and show the expected output if you can. It's helpful to have inline the smallest example of usage that you can demonstrate, while providing links to more sophisticated examples if they are too long to reasonably include in the README.
-
-## Support
-Tell people where they can go to for help. It can be any combination of an issue tracker, a chat room, an email address, etc.
-
-## Roadmap
-If you have ideas for releases in the future, it is a good idea to list them in the README.
-
-## Contributing
-State if you are open to contributions and what your requirements are for accepting them.
-
-For people who want to make changes to your project, it's helpful to have some documentation on how to get started. Perhaps there is a script that they should run or some environment variables that they need to set. Make these steps explicit. These instructions could also be useful to your future self.
-
-You can also document commands to lint the code or run tests. These steps help to ensure high code quality and reduce the likelihood that the changes inadvertently break something. Having instructions for running tests is especially helpful if it requires external setup, such as starting a Selenium server for testing in a browser.
-
-## Authors and acknowledgment
-Show your appreciation to those who have contributed to the project.
+networks:
+ app-network-1:
+ driver: bridge
+ attachable: true
+ app-network-2:
+ driver: bridge
+ attachable: true
+```
-## License
-For open source projects, say how it is licensed.
+### Running the Bridge Network Example
+
+1. Save the above YAML code in a file named `docker-compose.yaml`.
+2. Open your terminal and navigate to the directory containing `docker-compose.yaml`.
+3. Run the following command to start the services:
+ ```bash
+ docker-compose up -d
+ ```
+4. To check if everything is running smoothly, use:
+ ```bash
+ docker ps
+ ```
+5. To see logs for any service (e.g., `app1`):
+ ```bash
+ docker logs app1
+ ```
+
+This setup allows `app1` and `app2` to communicate with `rabbitmq` because they are attached to networks (`app-network-1` and `app-network-2`). However, since they are on different bridge networks, they can't directly communicate with each other unless we set up additional network rules.
+
+## Example 2: Using an Overlay Network in Docker Swarm
+
+### What Is an Overlay Network?
+
+An overlay network allows containers to communicate across different machines (nodes) in a Docker Swarm. You can think of it as a virtual network that spans across multiple Docker hosts.
+
+### Prerequisites for Overlay Networks
+
+You need a Docker Swarm cluster with at least three virtual machines (VMs). Let’s call them **VM1**, **VM2**, and **VM3**. You can use cloud services (like AWS or Azure) or local VMs.
+
+### Overlay Network Docker Compose File
+
+Here’s the `docker-compose.yaml` for the overlay network setup:
+
+```yaml
+version: '3.8'
+
+services:
+ rabbitmq:
+ image: rabbitmq:3-management
+ container_name: rabbitmq
+ ports:
+ - "5672:5672" # RabbitMQ default messaging port
+ - "15672:15672" # RabbitMQ management console
+ networks:
+ - app-network-1
+ - app-network-2
+
+ app1:
+ image: franciscomendonca/auto-messaging:1.0.1
+ restart: on-failure
+ environment:
+ - START_WITH_MESSAGE=true # Start by sending a message
+ - RABBITMQ_HOST=rabbitmq
+ depends_on:
+ - rabbitmq
+ networks:
+ - app-network-1
+
+ app2:
+ image: franciscomendonca/auto-messaging:1.0.1
+ container_name: app2
+ restart: on-failure
+ environment:
+ - START_WITH_MESSAGE=false # Wait for a message before responding
+ - RABBITMQ_HOST=rabbitmq
+ depends_on:
+ - rabbitmq
+ networks:
+ - app-network-2
+
+networks:
+ app-network-1:
+ driver: overlay
+ attachable: true
+ app-network-2:
+ driver: overlay
+ attachable: true
+```
-## Project status
-If you have run out of energy or time for your project, put a note at the top of the README saying that development has slowed down or stopped completely. Someone may choose to fork your project or volunteer to step in as a maintainer or owner, allowing your project to keep going. You can also make an explicit request for maintainers.
+### How to Set Up and Run the Overlay Network Example
+
+1. **Create Virtual Machines (VMs):** Set up three VMs (VM1, VM2, VM3).
+2. **Install Docker on Each VM:**
+ ```bash
+ sudo apt-get update
+ sudo apt-get install ca-certificates curl
+ sudo install -m 0755 -d /etc/apt/keyrings
+ sudo curl -fsSL https://download.docker.com/linux/ubuntu/gpg -o /etc/apt/keyrings/docker.asc
+ sudo chmod a+r /etc/apt/keyrings/docker.asc
+
+ echo "deb [arch=$(dpkg --print-architecture) signed-by=/etc/apt/keyrings/docker.asc] https://download.docker.com/linux/ubuntu $(. /etc/os-release && echo "$VERSION_CODENAME") stable" | sudo tee /etc/apt/sources.list.d/docker.list > /dev/null
+ sudo apt-get update
+ sudo apt-get install docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin
+ ```
+ If you run into permission issues, use:
+ ```bash
+ sudo groupadd docker
+ sudo usermod -aG docker $USER
+ newgrp docker
+ ```
+3. **Initialize Docker Swarm on VM1:**
+ ```bash
+ docker swarm init
+ ```
+ - Copy the command it gives (starting with `docker swarm join ...`) and run it on **VM2** and **VM3** to add them to the swarm.
+4. **Copy the `docker-compose.yaml` to VM1:**
+ ```bash
+ scp -i .ssh/<KEY_NAME> docker-compose.yaml <USER>@<VM1_IP>:/home/<USER>
+ ```
+5. **Deploy the Stack on VM1:**
+ ```bash
+ docker stack deploy -c docker-compose.yaml mystack
+ ```
+6. **Check the Status and Logs:**
+ ```bash
+ docker stack services mystack
+ docker stack logs app1
+ ```
+
+And that's it! You've now deployed an application using Docker Swarm and overlay networks. In this setup, `app1` and `app2` can communicate across different VMs.
+
+### Summary
+
+- **Bridge Networks** are great for communication on a single Docker host.
+- **Overlay Networks** enable container communication across multiple hosts in a Docker Swarm.
+
+By following this tutorial, you should now have a basic understanding of how to use bridge and overlay networks in Docker!
\ No newline at end of file
diff --git a/container-networking/Dockerfile b/container-networking/Dockerfile
new file mode 100644
index 0000000000000000000000000000000000000000..94c309e60bc8ed00f19ab7ddbfc90dcec53174c9
--- /dev/null
+++ b/container-networking/Dockerfile
@@ -0,0 +1,17 @@
+# Use the official Python image from the Docker Hub
+FROM python:3.9-slim
+
+# Set environment variables to reduce Python's buffer for more efficient logging
+ENV PYTHONUNBUFFERED=1
+
+# Create a directory for the app
+WORKDIR /app
+
+# Copy the current directory (where your script is) to /app in the container
+COPY . /app
+
+# Install requirements - NOTE: --no-cache-dir prevents pip from storing downloaded files in local cache (reduces image size).
+RUN pip install --no-cache-dir -r requirements.txt
+
+# Set the default command to run the Python script
+CMD ["python", "main.py"]
diff --git a/container-networking/docker-compose.yaml b/container-networking/docker-compose.yaml
new file mode 100644
index 0000000000000000000000000000000000000000..3f5d5f91e6b5935fd43e16dc95ebbb524dfd0a78
--- /dev/null
+++ b/container-networking/docker-compose.yaml
@@ -0,0 +1,43 @@
+version: '3.8'
+
+services:
+ rabbitmq:
+ image: rabbitmq:3-management
+ container_name: rabbitmq
+ ports:
+ - "5672:5672" # RabbitMQ default messaging port
+ - "15672:15672" # RabbitMQ management console
+ networks:
+ - app-network-1
+ - app-network-2
+
+ app1:
+ image: franciscomendonca/auto-messaging:1.0.1
+ restart: on-failure
+ environment:
+ - START_WITH_MESSAGE=true # Start by sending a message
+ - RABBITMQ_HOST=rabbitmq
+ depends_on:
+ - rabbitmq
+ networks:
+ - app-network-1
+
+ app2:
+ image: franciscomendonca/auto-messaging:1.0.1
+ container_name: app2
+ restart: on-failure
+ environment:
+ - START_WITH_MESSAGE=false # Wait for a message before responding
+ - RABBITMQ_HOST=rabbitmq
+ depends_on:
+ - rabbitmq
+ networks:
+ - app-network-2
+
+networks:
+ app-network-1:
+ driver: overlay
+ attachable: true
+ app-network-2:
+ driver: overlay
+ attachable: true
\ No newline at end of file
diff --git a/container-networking/main.py b/container-networking/main.py
new file mode 100644
index 0000000000000000000000000000000000000000..99f5eadca1c87bfa8d3f37fe03b057247465125d
--- /dev/null
+++ b/container-networking/main.py
@@ -0,0 +1,77 @@
+import pika
+import time
+import random
+import os
+import logging
+import uuid
+
+# Set up logging
+logging.basicConfig(level=logging.INFO)
+
+# Set up connection parameters
+rabbitmq_host = os.getenv('RABBITMQ_HOST') # RabbitMQ container name
+
+# Check if the RabbitMQ host is set
+if not rabbitmq_host:
+ logging.error("RABBITMQ_HOST environment variable is not set")
+ exit(1)
+
+logging.info(f"RabbitMQ host: {rabbitmq_host}")
+connection_params = pika.ConnectionParameters(host=rabbitmq_host)
+
+# Function to send messages
+def send_message(channel, message):
+ # Send a message back to the queue
+ channel.basic_publish(exchange='',
+ routing_key='test_queue',
+ body=message)
+
+ print(f" [x] Sent '{message}'")
+
+# Function to handle received messages and send a response
+def on_message_received(ch, method, properties, body):
+ received_message = body.decode()
+ print(f" [x] Received '{received_message}'")
+
+ # Create a response message
+ response_message = f"Response to '{received_message}' from {random.randint(1, 1000)}"
+
+ # Simulate some processing time
+ time.sleep(2)
+
+ # Send the response message
+ send_message(ch, response_message)
+
+# Function to start the auto-messaging system
+def start_auto_messaging(start_with_message):
+ # Set up a connection and channel
+ logging.info(f"Establishing connection: {connection_params}")
+ connection = pika.BlockingConnection(connection_params)
+ channel = connection.channel()
+
+ logging.info("Connection established")
+
+ # Declare a queue
+ channel.queue_declare(queue='test_queue')
+
+ # Check if the system should start by sending a message
+ if start_with_message:
+ logging.info("Starting with an initial message")
+ initial_message = f"Initial message from {random.randint(1, 1000)}"
+ send_message(channel, initial_message)
+
+ # Start consuming and handle each message with the on_message_received function
+ channel.basic_consume(queue='test_queue',
+ on_message_callback=on_message_received,
+ auto_ack=True)
+
+ print(' [*] Waiting for messages. To exit press CTRL+C')
+ channel.start_consuming()
+
+if __name__ == '__main__':
+ # Read environment variable to check if the system should start by sending a message
+ start_with_message = os.getenv('START_WITH_MESSAGE', 'false').lower() == 'true'
+ logging.info(f"Does it start messaging: {start_with_message}")
+
+ # Start the auto-messaging system
+ start_auto_messaging(start_with_message)
diff --git a/container-networking/requirements.txt b/container-networking/requirements.txt
new file mode 100644
index 0000000000000000000000000000000000000000..73da9f7057bb2c116dace2bf8ddbd89f1f2a201f
--- /dev/null
+++ b/container-networking/requirements.txt
@@ -0,0 +1 @@
+pika
\ No newline at end of file