Komga

Komga is a free and open source comics/mangas server.

Features

Komga just started, and for now it can:

• scan and index a folder containing comic book archives in cbz and cbr format, as well as pdf. Rescan periodically.
• serve the individual pages of those books via an API
• serve the complete file via an API

Status & vision

The first version is a simple server with only an API and no UI. It's aimed to work with Tachiyomi through an extension.

Future versions may bring:

• support for multiple libraries (multiple folders)
• a web UI to administrate the server
• matching with online metadata sources (like ComicVine) to enrich information like description or genre

The long term vision is to offer something similar to Plex, but for comics!

What does it do?

Komga will scan your library's root folder for directories containing supported files (at the moment cbz, zip, cbr, rar and pdf):

• each folder containing comic books will be made as a Serie
• each comic book file inside a Serie will be made as a Book

It works with subfolders too, so if you have a structure like this:

-Parent
+--SubFolder
| +file1.cbz
| +file2.cbz
+direct1.cbz

Komga will generate:

• a Serie called Parent, containing a Book called direct1
• a Serie called SubFolder, containing two Books called file1 and file2

On rescans, Komga will update Series and Books, add new ones, and remove the ones for which files don't exist anymore.

Then it will parse each book, which consist of indexing pages (images in the archive), and generating a thumbnail.

Komga offers a REST API, which you can browse using Swagger. It's available at /swagger-ui.html. The API offers file download and page streaming.

In order to access the API, you will need to authenticate using Basic Authentication, with one of the 2 built-in users (admin or user).

Installation

The easiest way to install Komga is to use Docker. You can have a look at the sample docker-compose.yml.

Alternatively you can run it from the fat jar file. You can find them in the releases section.

You can also build it yourself by using gradlew bootJar to generate it.

Configuration

Komga relies heavily on Spring Boot's configuration, leveraging profiles and configuration properties.

The easiest way to configure is either via environment variables (a good fit for docker-compose) or by using an application.yml file located in the same folder as the jar file. You can check the sample application.yml.

Each configuration key can have a different format depending if it's from the environment variable, or from the application.yml file. In the following section I will provide both format in the form ENVIRONMENT_VARIABLE / application-property.

Mandatory configuration

In order to make Komga run, you need to specify some mandatory configuration keys (unless you use Docker, in which case defaults are setup):

• SPRING_PROFILES_ACTIVE / spring.profiles.active: prod - this will enable the database management and upgrades for new versions.
• SPRING_DATASOURCE_URL / spring.datasource.url: the path of the database file. For Docker I use jdbc:h2:/config/database.h2;DB_CLOSE_DELAY=-1, where /config/database.h2 is the actual file inside the docker container. You can customize this part if running without docker.
• KOMGA_ROOT_FOLDER / komga.root-folder: the root folder of your library, this is what Komga will scan.
• KOMGA_ROOT_FOLDER_SCAN_CRON / komga.root-folder-scan-cron: a Spring cron expression for root folder periodic rescans. 0 0 * * * ? will rescan every hour. 0 */15 * * * ? will rescan every 15 minutes.

Optional configuration

You can also use some optional configuration keys:

• KOMGA_USER_PASSWORD / komga.user-password: the password for the user user. Defaults to user.
• KOMGA_ADMIN_PASSWORD / komga.admin-password: the password for the user admin. Defaults to admin.
• KOMGA_THREADS_PARSE / komga.threads.parse: the number of worker threads used for book parsing. Defaults to 2. You can experiment to get better performance.

Credits

The Komga icon is based on an icon made by Freepik from www.flaticon.com