MMA format

MMA (Mankai Manga Archive) is a ZIP-based book format for Mankai. One .mma file contains a manga’s metadata, chapter groups, cover, and page images. Use it to package a book with multiple chapters in a single file.

For importing or opening an archive from a local folder or network share, see Add books and sources.

File identification

Property	Value
Extension	`.mma`
MIME type	`application/vnd.mankai.mma+zip`
Apple Uniform Type Identifier	`app.mankai.mma`
Container	ZIP

Archive layout

Place a file named exactly metadata.json at the ZIP root. Cover and page paths in the metadata are relative to that root. Image folders and filenames are up to you. The metadata explicitly identifies the files to read.

example.mma
├── metadata.json
├── cover.jpg
└── chapters/
    ├── chapter-1/
    │   ├── 001.jpg
    │   └── 002.jpg
    └── chapter-2/
        └── 001.jpg

Metadata

The root of metadata.json is a manga object. It uses Mankai’s detailed manga fields, with a required chapters array of chapter groups and an additional images array on each chapter.

{
  "id": "example-manga",
  "title": "Example Manga",
  "cover": "cover.jpg",
  "status": 1,
  "readingDirection": 2,
  "authors": ["Example Author"],
  "genres": ["adventure"],
  "description": "A two-chapter example.",
  "chapters": [
    {
      "id": "main",
      "title": "Main story",
      "chapters": [
        {
          "id": "chapter-1",
          "title": "Chapter 1",
          "images": ["chapters/chapter-1/001.jpg", "chapters/chapter-1/002.jpg"]
        },
        {
          "id": "chapter-2",
          "title": "Chapter 2",
          "images": ["chapters/chapter-2/001.jpg"]
        }
      ]
    }
  ]
}

Manga fields

Field	Type	Required	Meaning
`id`	`string`	Yes	Manga identifier in the metadata. File-based sources replace it with their own file identity when opening the book.
`title`	`string`	No	Display title.
`cover`	`string`	No	Path to a cover image inside the archive.
`status`	`number`	No	`0` = any, `1` = ongoing, `2` = completed.
`readingDirection`	`number`	No	`1` = left to right, `2` = right to left, `3` = vertical.
`latestChapter`	`object`	No	A chapter reference with required `id` and optional `title` and `locked` fields. Its ID must match a chapter in `chapters`. No `images` field is required here.
`description`	`string`	No	Manga description.
`externalLink`	`string`	No	Link to an external page about the manga.
`updatedAt`	`number`	No	Unix timestamp in milliseconds.
`authors`	`string[]`	No	Author names. Defaults to `[]`.
`genres`	`string[]`	No	Mankai genre values, such as `action` or `adventure`. Defaults to `[]`.
`chapters`	`object[]`	Yes	Ordered chapter groups, containing at least one chapter overall.
`remarks`	`string`	No	Additional remarks.

Chapter groups

Each entry in the top-level chapters array is a group:

Field	Type	Required	Meaning
`id`	`string`	No	Group identifier.
`title`	`string`	Yes	Group title.
`chapters`	`object[]`	Yes	Ordered chapters in this group. A group may be empty, but the archive must contain at least one chapter overall.

Chapters

Each chapter in a group has these fields:

Field	Type	Required	Meaning
`id`	`string`	Yes	Nonempty chapter ID, unique across all groups in the archive.
`title`	`string`	No	Chapter title.
`locked`	`boolean`	No	Whether the chapter is locked in the app. Omit it or use `false` for readable chapters.
`images`	`string[]`	Yes	Nonempty list of archive-relative image paths in reading order.

Image paths and covers

Use forward-slash paths that match regular file entries in the ZIP, such as cover.jpg or chapters/chapter-1/001.jpg. Use the image formats supported by the client platform, such as JPEG and PNG.

Both cover and every images entry must satisfy these rules:

The path is nonempty and relative to the ZIP root. It cannot start with /.
No component is empty, . or ... Leading, trailing, and repeated slashes are invalid.
Backslashes and null characters are forbidden.
The first component cannot contain :. Absolute URLs and drive-prefixed paths are invalid.