Weatherapp

This copy holds my solutions to a selective list of tasks/exercises put forward by Eficode on their Weatherapp repo. Taking on the challenge sounded like a great learning activity to practice concepts like containerization, cloud infrastructure and automated deployments with Ansible. Hence, my solutions will be to the tasks related to these topics.

Prerequisites

• Sign up/in to OpenWeatherMap, and get an API key.
• Create a .env file in the root directory with the following information:

  APPID=<YOUR_OPENWEATHERMAP_API_KEY>
  ENDPOINT=http://0.0.0.0:9000/api
  

Exercises

The app itself is a backend API that pulls weather data from OpenWeatherMap before serving it to a simple React frontend which displays a large current weather icon.

The challenge guidelines I am working with in my plan include a few exercises. The first is Docker containerization. Then, setting up the containerized app with a cloud service provider. Finally, a choice of either a CI/CD pipeline, or automated deployments with Ansible.

The following sections will be updated as I continue going through the tasks.

Docker

Docker containers are central to any modern development initiative. By knowing how to set up your application into containers and make them interact with each other, you have learned a highly useful skill.

• Add Dockerfile-s in the frontend and the backend directories to run them virtually on any environment having Docker installed. It should work by saying e.g. docker build -t weatherapp_backend . && docker run --rm -i -p 9000:9000 --name weatherapp_backend -t weatherapp_backend. If it doesn't, remember to check your api key first.
• Add a docker-compose.yml -file connecting the frontend and the backend, enabling running the app in a connected set of containers.
• The developers are still keen to run the app and its pipeline on their own computers. Share the development files for the container by using volumes, and make sure the containers are started with a command enabling hot reload.

The first two requirements were a straightforward Docker image-building and container-running implementation. The challenge is mainly the third point, where we need a development workflow that allows for hot reloads and utilizes shared volumes.

The implementation here involves the use of a lightweight Node-13 base image, two new docker-compose files, and a Makefile to make things easier.

• docker-compose.dev-build.yml is used for setting up NPM modules for both, the backend and frontend, on their own external Docker volumes
• docker-compose.dev-run.yml is used for starting up the backend in debug mode, and the frontend in a hot reload development mode.

Usage

• Clone the repo and cd weatherapp/
• On first run, create the necessary Docker volumes with make init
• Run docker volume ls and you should see the two newly built volumes weatherapp_backend_node_modules and weatherapp_frontend_node_modules
• From now on, everytime the packages.json file is changed, run make modules to do the module installations and persist them on the shared modules volumes
• Otherwise, run make hotrun to start both sides of the app in a hot/live-reload mode
• When ready for deployment, run make containers or docker-compose up to build the images via the Dockerfile-s and run the containers
• Check if everything is OK, then kill the containers and push and/or deploy the weatherapp_backend and weatherapp_frontend images

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A Note regarding Node-13:

The app ran well on my local Node v13.8.0, but caused some errors within the the v13.10 Docker image. This is why I explicitly selected the node:13.8.0-alpine3.11 image

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Cloud

The biggest trend of recent times is developing, deploying and hosting your applications in cloud. Knowing cloud -related technologies is essential for modern IT specialists.

• Set up the weather service in a free cloud hosting service, e.g. AWS or Google Cloud.

In progress... (I am considering what features this section can add to the Ansible section below)

Ansible

Automating deployment processes saves a lot of valuable time and reduces chances of costly errors. Infrastructure as Code removes manual steps and allows people to concentrate on core activities.

• Write Ansible playbooks for installing Docker and the app itself.

The whole Ansible deployment workflow is available on the weatherapp-ansible repo