# AppStream collection YAML

## Introduction

DEP-11 is a YAML implementation of the AppStream collection specification, which is primarily used by Debian and its derivatives. This document describes the DEP-11 YAML. All AppStream support libraries available today are able to read both the YAML and the XML specification.

If you want to use AppStream in your distribution, and are not based on Debian, please use the XML specification (unless you have strong reasons for preferring YAML). XML is the official format for AppStream collection metadata.

The DEP-11 YAML metadata can be validated for correctness using the `dep11-validate` tool from the AppStream DEP-11 utils.

Fields not mentioned in this document are not recognized by DEP-11 YAML parsers.

## File naming and location

Take a look at for AppStream XML files. While the XML data belongs into the `xmls` subdirectory in `/usr/share/app-info` (or `/var/cache/app-info`), the YAML data is stored in the `yaml` subdirectory. All other rules affecting the XML apply the DEP-11 YAML as well, including the recommendation to compress the files with gzip.

## General DEP-11 YAML structure

Each YAML file starts with a header document, which defines the basic properties of the metadata, which is followed by the actual metadata in form of one YAML document per AppStream component.

The header document contains the following fields, all of them are required or at least strongly recommended.

File

  This field identifies the file as DEP-11 file. Its value is always `DEP-11`.

      Field info: value-type:str, required:yes

Version

  The version of the AppStream specification this file was built for.

      Field info: value-type:str, required:yes

Origin

  Defines the repository-id this file belongs to. This usually matches the filename without extension. On Debian systems, it is the `<suite>-<component>` combination, e.g. `jessie-main`.

      Field info: value-type:str, required:yes

MediaBaseUrl

  The base URL for media (screenshots, icons, ...) referenced in the metadata file. If this is set, all urls in the document referencing media will be treated relative to the base url.

      Field info: value-type:str, required:no

Architecture

  Defines the architecture this data belongs to. This information is useful to resolve AppStream-ID conflicts on multiarch systems, which appear if the user has metadata for two architectures installed.

      Field info: value-type:str, required:no

Priority

  The priorization of this metadata file over other metadata.

      Field info: value-type:int, required:no

## Translated fields

Fields with translated values follow the following conventions:

1. They are of type dict

2. They must contain a key `C`, with the untranslated string as value

3. All languages are represented with their locale name as key in the dict and the translated content as value (which is of type str, unless explicitly stated otherwise)

In this document, the type localized is used to indicate that the field contains translated values following this schema.

Example for a translated `Name` field:

    Name:
      C: I am the untranslated string.
      be@latin: Redaktar naładaŭ
      bg: Настройки на програмите
      pl: Edytor konfiguracji

## Valid fields

This document describes all valid fields in the DEP-11 YAML specification. The requirements for the values are exactly the same as in the XML specification, and each field links to its correspondent XML tag for reference.

ID

  The `ID` field is a short unique and usually lower-cases identifier for the component. Depending on the component's type, different naming conventions apply.

  See .

      Field info: value-type:str, required:yes

Priority

  The `Priority` field sets the priority this component's metadata should have over other meadata in the pool. Data with a higher priority replaces data with a lower priority.

  See .

      Field info: value-type:int, required:no

Type

  The type of this component. Allowed values are:

  - `generic` for

  - `desktop-application` for

  - `console-application` for

  - `addon` for

  - `codec` for

  - `inputmethod` for

  - `firmware` for

      Field info: value-type:str, required:yes

Merge

  The optional `Merge` field describes the merge strategy that should be applied when merging data of this component into its base. It may assume the values `append` or `replace`.

  See for a description on how merging works.

      Field info: value-type:str, required:no

Package

  The name of the package which needs to be installed in order to make this component available on the system.

  See .

      Field info: value-type:str, required:yes

SourcePackage

  See .

      Field info: value-type:str

Name

  See .

      Field info: value-type:localized, required:yes

Summary

  See .

      Field info: value-type:localized, required:yes

ProjectLicense

  See .

      Field info: value-type:str

Description

  See .

  The markup for the description is the same as in the XML specification, so it can be read by anything parsing basic HTML markup.

      Field info: value-type:localized

Url

  See .

  The `Url` field contains the different url types as keys in its dict. Valid url types are defined in the main AppStream XML specification. All URL types must be lowercased.

  Example:

      Url:
        homepage: http://example.org
        faq: http://example.org/faq
        bugtracker: http://bugs.example.org/report-issue

      Field info: value-type:dict

ProjectGroup

  See .

      Field info: value-type:str

Icon

  See .

  The `Icon` field has the different icon types as keys for its dict.

  stock

    Contains the stock icon name.

        Field info: value-type:str

  cached

    Contains a list of dictionaries with the keys `width` and `height` of type int specifying the dimensions of the icon, as well as the key `name` of type str specifying the name of the icon in the cache.

        Field info: value-type:list ➟ dict

  local

    Contains a list of dictionaries with the keys `width` and `height` of type int specifying the dimensions of the icon, as well as the key `name` of type str specifying the absolute filename pointing to the right icon.

        Field info: value-type:list ➟ dict

  remote

    Contains a list of dictionaries with the keys `width` and `height` of type int specifying the dimensions of the icon, as well as the key `url` of type str which contains a HTTP(S) or FTP URL to the icon.

        Field info: value-type:list ➟ dict

      Field info: value-type:dict

Categories

  See .

  This field follows its XML counterpart in almost all regards. The different XDG menu category names are encoded in the list, and are of type str.

  Example:

      Categories:
        - Network
        - Telephony

      Field info: value-type:list

Keywords

  See .

  This field contains the keywords for this component. The keys define the locales for the respective language, the values are of type list and contain the list of keywords for the respective language. An unlocalized `C` key must be present.

  Example:

      Keywords:
        C:
          - IDE
          - development
          - programming
        de:
          - IDE
          - entwicklung
          - programmierung

      Field info: value-type:translated(list)

Screenshots

  See .

  The `Screenshots` field contains a list of screenshots. A screenshot is of type dict and contains the following keys:

  default

    If `default` is `true`, the screenshot is selected as default screenshot. There has to be at least one screenshot which is marked as default.

        Field info: value-type:bool

  source-image

    Describes the source image for this screenshot. It has the following keys:

    - `height`

      The image height (value-type:int)

    - `width`

      The image width (value-type:int)

    - `url`

      The full image url, or the url component added to `MediaBaseUrl`, if defined (value-type:str).

    - `lang`

      The language this screenshot image is translated in. The value is a locale string. (value-type:str, required:no)

        Field info: value-type:dict, required:yes

  thumbnails

    A list of an arbitrary number of screenshots. All screenshots are of type dict and must contain the same keys as described for `source-image`.

        Field info: value-type:list, required:no

  caption

    A caption for this screenshot.

        Field info: value-type:localized

  Example for a `Screenshots` field containing one screenshot:

      Screenshots:
        - default: true
          caption:
            C: Foobar showing kitchen-sink functionality
            si: Foobar shoeewing kischän-sünk funzionality
          source-image:
            height: 800
            url: http://www.example.org/en_US/main.png
            width: 600
          thumbnails:
            - height: 423
              width: 752
              url: http://www.example.org/en_US/main-large.png
            - height: 63
              width: 112
              url: http://www.example.org/en_US/main-small.png

      Field info: value-type:list

CompulsoryForDesktop

  See .

      Field info: value-type:str

Provides

  See .

  The `Provides` field is of type dict and can have the following keys set with the described allowed values:

  libraries

    A list of provided library names.

        Field info: value-type:list(str)

  binaries

    A list of provided binaries in `PATH`.

        Field info: value-type:list(str)

  mimetypes

    A list of mimetypes this component can handle.

        Field info: value-type:list(str)

  firmware

    A list of provided firmware. Each firmware entry is of type dict and has a `type` key, which has either `runtime` or `flashed` as value. Firmware of type `flashed` has a `guid` key, containing the GUID of the device the firmware is flashed on, while firmware of type `runtime` has a `file` key, containing the firmware filename which the kernel is looking for.

        Field info: value-type:list(dict)

  dbus

    A list of provided DBus services. Each service entry in the list is of type dict and has a `type` key, which has either `system` or `user` as value. `user` means the DBus service name is for a user/session service, while `system` means it describes a system service. The `service` key contains the name of the DBus service file. All dict values are of type str.

        Field info: value-type:list(dict)

      Field info: value-type:dict

DeveloperName

  See .

      Field info: value-type:localized

Releases

  See .

  The `Releases` contains a list of releases, where each list items contains the following fields/keys:

  version

    The version number of this release.

        Field info: value-type:str, required:yes

  unix-timestamp

    The UNIX timestamp of when this software was released.

    One of the `unix-timestamp` or `date` fields must be present.

        Field info: value-type:int, required:maybe

  date

    The ISO 8601 date of when this software was released.

    One of the `unix-timestamp` or `date` fields must be present.

        Field info: value-type:str, required:maybe

  description

    A description of this release. May contain allowed HTML markup.

        Field info: value-type:localized

  It is recommended to order this list starting with the latest timestamp to the olderst one.

  Example:

      Releases:
        - version: '1.8'
          unix-timestamp: 1424116753
          description:
            C: |
              <p>This stable release fixes the following bug:</p>
              <ul>
                <li>CPU no longer overheats when you hold down spacebar</li>
              </ul>
        - version: '1.2'
          unix-timestamp: 1397253600
        - version: '1.0'
          unix-timestamp: 1345932000

      Field info: value-type:list(dict)

Languages

  See .

  The languages list is a list of dictionaries. They must contain a `percentage` key, indicating the completion of translation for this language, and a `locale` key, with the locale string as value.

  Example:

      Languages:
        - locale: gu
          percentage: 96
        - locale: ca@valencia
          percentage: 94
        - locale: de
          percentage: 91
        - locale: eo
          percentage: 93

      Field info: value-type:list(dict)

Bundles

  See .

  The `Bundles` contains a list of dictionaries with the keys `type`, having the ID for a specific bundling system (e.g. `flatpak` or `limba`) as value, and `id` for the associated bundle-id. See the XML tag description for information on all valid bundling systems.

  Example:

      Bundles:
        - type: limba
          id: foobar-1.0.2

      Field info: value-type:list

Extends

  See .

  Contains a list of AppStream IDs of the other component extended by the described component. This field may only be used with component-type `addon`.

      Field info: value-type:list(str)

Suggests

  See .

  A list of dictionaries containing suggested software components. The dictionaries must have a `type` key with the string value `upstream` or `heuristic` depending on where the suggestion originates from. The also must have a `ids` key containing a list of component-ids of the suggested software.

  Example:

      Provides:
        - type: upstream
          ids:
            - org.example.Awesome
        - type: heuristic
          ids:
            - org.example.Test1
            - org.example.Test2

      Field info: value-type:list(dict)

## Example YAML file

This is an example AppStream DEP-11 metadata file:

    ---
    File: DEP-11
    Version: '0.8'
    Origin: chromodoris-main
    MediaBaseUrl: http://metadata.tanglu.org/appstream/media/
    ---
    Type: desktop-application
    ID: gconf-editor.desktop
    Icon:
      cached: gconf-editor_gconf-editor.png
    Name:
      C: Configuration Editor
      be@latin: Redaktar naładaŭ
      bg: Настройки на програмите
      pl: Edytor konfiguracji
    Package: gconf-editor
    Summary:
      C: Directly edit your entire configuration database
      ar: حرّر مباشرة كامل قاعدة بيانات الإعدادات.
      de: Direkten Zugriff auf Ihre gesamte Konfigurationsdatenbank erlangen
    Categories:
      - GNOME
      - GTK
      - System
    ---
    Type: desktop-application
    ID: kmplayer.desktop
    Icon:
      cached: kmplayer_kmplayer.png
    Name:
      C: KMPlayer
      hi: केएम-प्लेयर
      hne: केएम-प्लेयर
      ku: KMLêdar
      pa: KM-ਪਲੇਅਰ
      sr: КМ‑плејер
      sr@ijekavian: КМ‑плејер
      sv: Kmplayer
    Package: kmplayer
    Summary:
      C: KDE interface for MPlayer
    Categories:
      - Qt
      - KDE
      - AudioVideo
      - Player
    Provides:
      mimetypes:
        - application/ogg
        - application/smil
        - application/vnd.ms-asf
        - application/vnd.rn-realmedia
        - application/x-kmplayer
        - video/webm
        - video/x-avi
    ---
    ID: texstudio.desktop
    Type: desktop-application
    Package: texstudio
    Name:
      C: TeXstudio
    Summary:
      C: LaTeX development environment
      fr: Environnement de développement LaTeX
    Description:
      C: <p>TeXstudio is an integrated writing environment for creating LaTeX documents. It integrates editing,
        building and viewing into a single frontend.</p><p>Our goal is to make writing LaTeX as easy and comfortable
        as possible. This is achieved through a rich feature set including:</p>
    Icon:
      cached: texstudio_texstudio.png
    Keywords:
      C:
        - editor
        - latex
        - pdflatex
        - xelatex
        - lualatex
        - context
        - bibtex
    ProjectLicense: GPL-2.0
    Url:
      homepage: http://texstudio.sourceforge.net/
    Categories:
      - Office
      - Publishing
    Provides:
      mimetypes:
        - text/x-tex
    Screenshots:
      - default: true
        source-image:
          height: 756
          url: texstudio_2.8.4+debian-3_amd64/screenshots/source/screenshot-1.png
          width: 1344
        thumbnails:
          - height: 423
            url: texstudio_2.8.4+debian-3_amd64/screenshots/752x423/screenshot-1.png
            width: 752
          - height: 351
            url: texstudio_2.8.4+debian-3_amd64/screenshots/624x351/screenshot-1.png
            width: 624
          - height: 63
            url: texstudio_2.8.4+debian-3_amd64/screenshots/112x63/screenshot-1.png
            width: 112