This project collects temperature values from a open weather map, stores city references in a backend and finally presents them in a angular web application.

In order to build the project you need docker www.docker.com with docker-compose docs.docker.com/compose and npm www.npmjs.com.

The project is organized in 3 seperate docker containers, bundled with docker-compose:

• A postgersql database
• A backend, written in golang. The source folder is: src/backend.
• a web frontend written in angular.js found in: src/client.

In order to access the open weather map API you need an API key. Open the file docker-compose.yml and edit the line containing:

OWM_ACCESS_KEY: <secret>

and replace <secret> with your own API key.

$ chmod +x ./build.sh
$ bash build.sh

The database is a default postgres image from docker hub without any custom configuration.

The backend is a Model-Repository-Controller backend, implemented with gorm as ORM Layer to the database. It encapsulates transport logic in the controllers, found in: src/backend/controllers, provides access to the (postgres) database with repositories in: src/backend/repositories and describes the database entities with model-interfaces found in: src/backend/entities. External services (open weather map) are implemented in: src/backend/services.

The backend implements a custom error handler and a unified logging facilty found in: src/backend/middleware. The controller and repo parts are CRUD services that implement the respective Index, Create, Read, Update and Delete opertaions.

When the application starts, the database connection gets established. Then a signal handler is initialized to a ensure clean shutdown procedure on SIGTERM events: basically a database disconnect, that enforces writing or rolling back pending transactions. It then proceeds to start a http server on the port 8082.

The frontend is bundled locally with npm and build in the target dir: src/client/dist. This will be used as entry point for a dockerized nginx webserver.