lucapernice/cloud_exam

Repo for cloud exam

Generate Volumes Script

The generate_volumes.sh is a bash script used to create a specific directory structure on your local machine. This script creates directories named data1-1, data1-2, ..., data4-2, and inside each directory, it creates subdirectories named data1 and data2.

To run this script, navigate to the directory containing the generate_volumes.sh file and use the following command:

bash generate_volumes.sh

Docker Compose File

The Docker Compose file is a YAML file that defines services, networks, and volumes. It allows you to manage your application's services as a single unit.

To deploy with Docker Compose, you need to have Docker and Docker Compose installed on your machine. Once installed, navigate to the directory containing your docker-compose.yml file and run the following command:

docker-compose up

This command will start and run your entire app. Docker Compose will pull the images for any services that need to be created, and start all the services defined in your docker-compose.yml file.

Locust File

The locustfile.py is a Python script that defines the behavior of users (locusts) in your system. It specifies what paths the users should hit and what data they should send.

In the provided locustfile.py, there are several tasks defined under the MinIOUser class. These tasks simulate the actions of uploading and downloading files to and from a MinIO server. The MinIO server's IP, port, access key, and secret key are defined in the on_start method.

Volumes

In Docker, a volume is a designated directory on the host machine that bypasses the Union File System, to provide several useful features for persistent or shared data:

• Volumes are initialized when a container is created.
• If the container's base image contains data at the specified mount point, that existing data is copied into the new volume upon volume initialization.
• Data volumes can be shared and reused among containers.
• Changes to a data volume are made directly.
• Changes to a data volume will not be included when you update an image.
• Data volumes persist even if the container itself is deleted.

In the context of the docker-compose.yml file, volumes are used to persist the data generated by and used by Docker containers. Even when the container stops, the volume data remains and can be reattached to other containers.

For example, if you have a volume named data i-j, you can use it in your services like this:

services:
  service_name:
    image: image_name
    volumes:
      - data i-j:/path/in/container

This will mount the data i-j volume to /path/in/container in the service_name service's containers. Any data the service writes to /path/in/container will be stored in the data i-j volume.