music-library

README

Music Library

The Music Library project is the result of a test assignment.

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C4 Architecture Visualization

Level 2: Containers

Level 3: Components

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Features

• Adding information about music tracks.
• Updating information about existing tracks.
• Deleting tracks from the library.
• Retrieving song lyrics with support for pagination by verses.
• Retrieving library content with support for filtering across all fields and pagination.
• Working with data through a REST API (API documentation is available in Swagger).
• Integration with Prometheus for collecting and storing application metrics.

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Potential Improvements

• Separate lyrics Table: Create a dedicated table for storing song lyrics, as a single song may have multiple lyrics associated with it.
• Optimize Update Method: Modify the current update method to perform data updates using a single query. (Refer to the documentation for postgres.Repository.UpdateSong() for the reasoning behind the current implementation.)
• Add Metrics Collection: Implement metrics collection for infrastructure layer packages to monitor performance and resource usage.

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Installation and Setup

1. Make sure you have the following installed:

   • Go version 1.23.2 or later.
   • Docker and Docker Compose.

2. Clone the repository:

   git clone https://github.com/FlutterDizaster/music-library
   cd music-library
   

3. Configure the application (see Configuration). The application can read configuration parameters from the env file, but environment variables have a higher priority. So for launching using docker compose, all configuration will take place in it. Please remember to provide the correct details server address.

4. Start the application containers:

   docker compose up -d
   

   If you use a port other than the default, you will need to make edits to the docker-compose.yaml.

5. To stop the application:

   docker compose down
   

The application will be available at http://<HTTP_ADDR>.

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Configuration

The application loads configuration parameters from the .env file, which must be created in the project root directory, or from environment variables. Available configuration parameters are listed below:

Variable Name	Description	Required
HTTP_ADDR	Service address (default: ":8080")	true
DATABASE_DSN	Database connection string (default: none)	true
DB_RETRY_COUNT	Number of retries for DB (default: 3)	false
DB_RETRY_BACKOFF	Time between DB reconnect retries (default: "1s")	false
MIGRATIONS_PATH	Path to migrations folder (default: "/migrations")	false
DETAILS_SERVER_ADDR	Address of the details server (default: "http://localhost:8081")	true
DETAILS_SERVER_RETRY_COUNT	Number of retries for details server (default: 3)	false
DETAILS_SERVER_RETRY_BACKOFF	Time between retries for details server (default: "1s")	false
DETAILS_SERVER_MAX_RETRY_BACKOFF	Max time between retries for details server (default: "10s")	false

Example .env file content:

HTTP_ADDR=:8080
DETAILS_SERVER_ADDR=http://localhost:8081
DATABASE_DSN=postgres://user:pass@localhost:5432/dbname?sslmode=disable

Make sure all parameters are correctly set before starting the application.

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Project Structure

.
├── cmd
│   └── main.go
├── docs
│   └── images
│       ├── c2.png
│       └── c3.png
├── internal
│   ├── apperrors
│   │   └── apperrors.go
│   ├── application
│   │   ├── application.go
│   │   ├── config
│   │   │   └── config.go
│   │   └── service
│   │       └── service.go
│   ├── domain
│   │   ├── interfaces
│   │   │   ├── details_repository.go
│   │   │   ├── music_repository.go
│   │   │   └── music_service.go
│   │   └── models
│   │       ├── filter.go
│   │       ├── library.go
│   │       ├── library_easyjson.go
│   │       ├── lyrics.go
│   │       ├── lyrics_easyjson.go
│   │       ├── pagination.go
│   │       ├── song.go
│   │       ├── song_detail.go
│   │       ├── song_detail_easyjson.go
│   │       ├── song_easyjson.go
│   │       ├── song_title.go
│   │       └── song_title_easyjson.go
│   ├── infrastructure
│   │   ├── http
│   │   │   └── detailsclient
│   │   │       └── detailsclient.go
│   │   ├── metrics
│   │   │   ├── metrics.go
│   │   │   └── metrics_registry.go
│   │   └── persistance
│   │       ├── migrator
│   │       │   └── migrator.go
│   │       └── postgres
│   │           ├── postgres_repository.go
│   │           └── queries.go
│   └── presentation
│       ├── handler
│       │   ├── handler.go
│       │   └── music.go
│       ├── middleware
│       │   ├── logger.go
│       │   ├── memory_writer.go
│       │   ├── metrics.go
│       │   └── middleware.go
│       └── server
│           └── server.go
├── migrations
│   ├── 001_create_songs_table.down.sql
│   └── 001_create_songs_table.up.sql
├── swagger
│   ├── docs.go
│   ├── swagger.json
│   └── swagger.yaml
├── Dockerfile
├── docker-compose.yaml
├── LICENSE
├── Makefile
├── README.md
├── go.mod
└── go.sum

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API

API documentation is available in the following files:

• swagger.json
• swagger.yaml

To view the documentation in a convenient interface, you can use Swagger UI or any other compatible tool.

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License

This project is licensed under the MIT License. See LICENSE for more details.