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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>Catalog Metadata | AppStream | AppStream 1.0</title><meta name="viewport" content="width=device-width, initial-scale=1.0, user-scalable=yes" /><link rel="stylesheet" type="text/css" href="static/css/style.css" /><link rel="stylesheet" type="text/css" href="static/css/highlight.css" /><meta name="generator" content="DAPS 3.3.2" /><meta name="product-name" content="AppStream" /><meta name="product-number" content="1.0" /><meta name="book-title" content="AppStream" /><meta name="chapter-title" content="Chapter 3. Catalog Metadata" /><meta name="description" content="Additionally to the metainfo files shipped by upstream projects, AppStream also provides an XML and YAML format to make information about not installed software components known to the system. This chapter documents this catalog metadata format and icon cache used on the client side. 3.1 AppStream C…" /><link rel="home" href="index.html" title="AppStream" /><link rel="up" href="index.html" title="AppStream" /><link rel="prev" href="sect-Metadata-Runtime.html" title="2.17. Runtime" /><link rel="next" href="sect-AppStream-YAML.html" title="3.2. AppStream Catalog YAML" />
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</script></head><body class="offline js-off"><div class="bypass-block"><a href="#_content">Jump to content</a><a href="#_bottom-navigation">Jump to page navigation: previous page [access key p]/next page [access key n]</a></div><div id="_outer-wrap"><div id="_white-bg"><div id="_header"><div id="_logo"><a href="https://www.freedesktop.org/software/appstream/docs/"><img src="static/images/logo.png" alt="Logo" /><span>AppStream</span></a></div><div class="crumbs"><a class="book-link" href="index.html" title="AppStream"><span class="book-icon">AppStream</span></a><span> › </span><a class="crumb" href="chap-CatalogData.html">Catalog Metadata</a></div><div class="clearme"></div></div></div><div id="_toolbar-wrap"><div id="_toolbar"><div id="_toc-area" class="inactive"><a id="_toc-area-button" class="tool" title="Contents" accesskey="c" href="index.html"><span class="tool-spacer"><span class="toc-icon">Contents</span><span class="clearme"></span></span><span class="tool-label">Contents</span></a><div class="active-contents bubble-corner"></div><div class="active-contents bubble"><div class="bubble-container"><h6>AppStream</h6><div id="_bubble-toc"><ol><li class="inactive"><a href="chap-AppStream-About.html"><span class="number">1 </span><span class="name">About AppStream</span></a></li><li class="inactive"><a href="chap-Metadata.html"><span class="number">2 </span><span class="name">Upstream Metadata</span></a></li><li class="inactive"><a href="chap-CatalogData.html"><span class="number">3 </span><span class="name">Catalog Metadata</span></a></li><li class="inactive"><a href="chap-AppStream-Misc.html"><span class="number">4 </span><span class="name">Miscellaneous</span></a></li><li class="inactive"><a href="chap-Quickstart.html"><span class="number">5 </span><span class="name">Metadata Quickstart</span></a></li><li class="inactive"><a href="chap-Validation.html"><span class="number">6 </span><span class="name">Data Validation</span></a></li><li class="inactive"><a href="chap-AppStream-ManualPages.html"><span class="number">7 </span><span class="name">Manual pages</span></a><ol>
	<a href="re01.html#id-1.8.3.1">appstreamcli</a>
	2012-2024Matthias Klumpp
	AppStream
	26 July,2012
	appstreamcli1appstreamcliHandle AppStream metadata formats and query AppStream dataappstreamcliCOMMAND<a href="re01.html#id-1.8.3.5">Description</a>
			This manual page documents briefly the appstreamcli command.
		
			appstreamcli is a small helper tool to work with AppStream metadata and
			access the AppStream component index from the command-line. The AppStream component
			index contains a list of all available software components for your distribution, matched to their
			package names.
			It is generated using AppStream XML or Debian DEP-11 data, which is provided by your distributor.
		
			For more information about the AppStream project and the other components which are part of it, take a look at
			the AppStream pages at Freedesktop.org.
		<a href="re01.html#id-1.8.3.6">Options</a>get IDGet a component from the metadata pool by its identifier.ssearch TERMSearch the AppStream component pool for a given search term.what-provides TYPE TERM
						Return components which provide a given item. An item type can be specified using the
						TYPE parameter, a value to search for has to be
						supplied using the TERM parameter.
					Examples:
						Get components which handle the "text/xml" mediatype.
					
						appstreamcli what-provides mediatype "text/xml"
					
						Get component which provides the "libfoo.so.2" library.
					
						appstreamcli what-provides lib libfoo.so.2
					refreshrefresh-cache
						Trigger a database refresh, if necessary.
						In case you want to force the database to be rebuilt, supply the --force flag.
					This command must be executed with root permission.status
						Display various information about the installed metadata and
						the metadata cache.
					os-info
						Show information about the current operating system from the metadata
						index.
						This requires the operating system to provide a operating-system
						component for itself.
					dump ID
						Dump the complete XML descriptions of components with the given ID that were found in the
						metadata pool.
					validate FILES
						Validate AppStream XML metadata for compliance with the specification.
					
						Both XML metadata types, upstream and distro XML, are handled.
						The format type which should be validated is determined automatically.
					
						The --pedantic flag triggers a more pedantic
						validation of the file, including minor and style issues in the report.
					validate-tree DIRECTORY
						Validate AppStream XML metadata found in a file-tree.
					
						This performs a standard validation of all found metadata, but also checks for additional
						errors, like the presence of .desktop files and validity of other additional metadata.
					check-license LICENSE
						Test a license string or license expression for validity and display details about it.
					
						This will check whether the license string is considered to be valid for AppStream, and return
						a non-zero exit code if it is not. The command will also display useful information like the
						canonical ID of a license, whether it is suitable as license for AppStream metadata,
						and whether the license is considered to be for Free and Open Source software or proprietary software.
					
						AppStream will consider any license as Free and Open Source that is marked as suitable by either the
						Free Software Foundation (FSF), Open Source Initiative (OSI) or explicit license list
						of the Debian Free Software Guidelines (DFSG).
					install ID
						Install a software component by its ID using the package manager or Flatpak.
					
						This resolves the AppStream component ID to an installation candidate and then
						calls either the native package manager or Flatpak (if available) to install
						the component.
					remove ID
						Uninstall a software component by its ID using the package manager or Flatpak.
					
						This will uninstall software matching the selected ID using either the native
						package manager or Flatpak (if available).
					put FILE
						Install a metadata file into the right directory on the current machine.
					compare-versionsvercmp VER1 [CMP] VER2
						Compare two version numbers. If two version numbers are given as parameters, the versions will be compared and the
						comparison result will be printed to stdout.
					
						If a version number, a comparison operator and another version number are passed in as parameter, the result of the comparison
						operation will be printed to stdout, and appstreamcli will exit with a non-zero exit status in case the comparison
						failed.
						The comparison operator can be one of the following:
					eq - Equal tone - Not equal tolt - Less thangt - Greater thanle - Less than or equal toge - Greater than or equal tonew-template TYPE FILE
						Create a metainfo file template to be used by software projects. The --from-desktop option can be used
						to use a .desktop file as template for generating the example file.
					
						The generated files contain example entries which need to be filed in with the actual desired values by the project author.
					
						The first TYPE parameter is the name of an AppStream component type. For a complete list check out
						the documentation or the help output
						of appstreamcli for this subcommand.
					make-desktop-file MI_FILE DESKTOP_FILE
						Create a XDG desktop-entry file from a metainfo file.
						If the desktop-entry file specified in DESKTOP_FILE already exists, it will get extended with
						the new information extracted from the metainfo file. Otherwise a new file will be created.
					
						This command will use the first binary mentioned in a provides tag of the component
						for the Exec= field of the new desktop-entry file.
						If this is not the desired behavior, the --exec flag can be used
						to explicitly define a binary to launch. Other methods of launching the application are currently not supported.
					
						In order to generate a proper desktop-entry, this command assumes that not only the minimally required tags for an
						AppStream component are set, but also that it has an &lt;icon/&gt; tag of type "stock" to describe
						the stock icon that should be used as well as a &lt;categories/&gt; tag containing the categories the application should
						be placed in.
					news-to-metainfo NEWS_FILE MI_FILE [OUT_FILE]
						This command converts a NEWS file as used by many open source projects into the XML used by AppStream. Since NEWS files are free text,
						a lot of heuristics will be applied to get reasonable results. The converter can also read a YAML version of the AppStream release
						description and convert it to XML as well.
						If the metainfo file MI_FILE already exists, it will be augmented with the new release entries, otherwise the release entries
						will be written without any wrapping component.
						If [OUT_FILE] is specified, instead of acting on MI_FILE the changed data will
						be written to the particular file. If any of the output filenames is set to "-", the output will instead be written to stdout.
					
						The --format option can be used to enforce reading the input file in a specific format ("text" or "yaml") in case the format autodetection fails.
						The --limit option is used to limit the amount of release entries written (the newest entries will always be first).
					metainfo-to-news MI_FILE NEWS_FILE
						This command reverses the news-to-metainfo command and writes a NEWS file as text or YAML using the XML
						contained in a metainfo file. If NEWS_FILE is set to "-", the resulting data
						will be written to stdout instead of to a file.
					
						The --format option can be used to explicitly specify the output format ("yaml" or "text"). If it is not set,
						appstreamcli will guess which format is most suitable.
					convert FILE1 FILE1
						Converts AppStream XML metadata into its YAML representation and vice versa.
					compose
						Composes an AppStream metadata catalog from a directory tree with metainfo files.
						This command is only available if the org.freedesktop.appstream.compose
						component is installed.
						See appstreamcli-compose1
						for more information.
					--detailsPrint out more information about a found component.--no-colorDon't print colored output.--no-netDo not access the network when validating metadata.
						The same effect can be achieved by setting the AS_VALIDATE_NONET environment variable
						before running appstreamcli.
					--versionDisplay the version number of appstreamcli<a href="re01.html#id-1.8.3.7">See Also</a>pkcon1.<a href="re01.html#id-1.8.3.8">AUTHOR</a>
	This manual page was written by Matthias Klumpp matthias@tenstral.net.

	<a href="re02.html#id-1.8.4.1">appstreamcli compose</a>
	2020-2024Matthias Klumpp
	AppStream
	28 Aug,2020
	appstreamcli compose1appstreamcli-composeCompose AppStream metadata catalog from directory treesappstreamcli composeCOMMAND<a href="re02.html#id-1.8.4.5">Description</a>
			This manual page documents briefly the appstreamcli compose command.
		
			The appstreamcli compose tool is used to construct AppStream metadata catalogs from directory trees.
			The tool will also perform many related metadata generation actions, like resizing icons and
			screenshots and merging in data from referenced desktop-entry files as well as translation status
			information.
			Therefore, the tool provides a fast way to test how the final processed metadata for an application
			that is shipped to users may look like.
			It also provides a way to easily generate AppStream data for projects which do not need a more complex data
			generator like appstream-generator.
		
			In order for the appstreamcli compose command to be available, you may need to install the
			optional compose module for appstreamcli first.
		
			For more information about the AppStream project and the other components which are part of it, take a look at
			the AppStream pages at Freedesktop.org.
		<a href="re02.html#id-1.8.4.6">Options</a>SOURCE-DIRECTORIES
						A list of directories to process needs to be provided as positional parameters.
						Data from all directories will be combined into one output namespace.
					--origin NAME
						Set the AppStream data origin identifier. This can be a value like
						"debian-unstable-main" or "flathub".
					--result-root DIR
						Sets the directory where all generated output that is deployed to a user's
						machine is exported to. If this parameter is not set and we only have one
						directory to process, we use that directory as default output path.
					
						If both --data-dir and --icons-dir are
						set, --result-root is not necessary and no data will be
						written to that directory.
					--data-dir DIR
						Override the directory where the generated AppStream metadata catalog
						will be written to. Data will be written directly to this directory, and
						no supdirectories will be created (unlike when using --result-root
						to set an output location).
					--icons-dir DIR
						Override the directory where the cached icons are exported to.
					--hints-dir DIR
						Set a directory where hints reported generated during metadata processing
						are saved to. If this parameter is not set, no HTML/YAML hint reports
						will be saved.
					--media-dir DIR
						If set, creates a directory with media content (icons, screenshots, ...) that
						can be served via a webserver. The metadata will be extended to include information
						about these remote media.
					--media-baseurl URL
						The URL under which the contents of a directory set via --media-dir
						will be served. This value must be set if a media directory is created.
					--prefix DIR
						Set the default prefix that is used in the processed directories. If
						none is set explicitly, /usr is assumed.
					--print-report MODE
						Print the issue hints report (that gets exported as HTML and YAML
						document when --hints-dir was set) to the console
						in text form.
					
						Various print modes are supported: on-error only prints a
						short report if the run failed (default), short generates
						an abridged report that is always printed and full results
						in a detailed report to be printed.
					--no-partial-urls
						If set, all URLs in the generated data will be absolute and media_baseurl will not be used.
						This makes changing the media mirror harder without regenerating all data and is generally not recommended,
						to increase flexibility.
					--icon-policy POLICY-STRING
						Override the existing icon policy with a custom one. The icon policy sets how icons of
						different sizes should be dealt with. They can be in the icon cache only, be a remote icon in
						the media location or be both cached and available in the remote location.
					
						The icon-policy string is comprised of comma-separated %{size}x%{size}@%{scale}=%{state} statements.
						The size and scale are that of the respective icon, with the scale being allowed to be
						omitted if it is 1. The state can be one of remote, cached or
						cached-remote.
					
						By default, a policy of 48x48=cached,48x48@2=cached,64x64=cached,64x64@2=cached,128x128=cached-remote,128x128@2=cached-remote
						is selected.
					--allow-custom CUSTOM-KEY-NAMES
						By default, all custom entries set in MetaInfo input data are removed.
						This flag allows one to whitelist custom keys to be propagated to the final catalog output data.
						The custom-key names should be provided as a comma-separated list.
					--components COMPONENT-IDs
						Set a comma-separated list of AppStream component IDs that should be
						considered for the generated metadata. All components that exist in
						the input data but are not mentioned in this list will be ignored
						for the generated output.
					--no-colorDon't print colored output.--verboseDisplay extra debugging information--versionDisplay the version number of appstreamcli compose<a href="re02.html#id-1.8.4.7">See Also</a>
			appstreamcli1,
			appstream-generator1.
		<a href="re02.html#id-1.8.4.8">AUTHOR</a>
	This manual page was written by Matthias Klumpp matthias@tenstral.net.
</ol></li><li class="inactive"><a href="chap-AppStream-API.html"><span class="number">8 </span><span class="name">AppStream API Reference</span></a></li><li class="inactive"><a href="ix01.html"><span class="number"> </span><span class="name">Index</span></a></li></ol></div><div class="clearme"></div></div></div></div><div id="_nav-area" class="inactive"><div class="tool"><span class="nav-inner"><span class="tool-label">Navigation</span><a accesskey="p" class="tool-spacer" title="2.17. Runtime" href="sect-Metadata-Runtime.html"><span class="prev-icon">←</span></a><a accesskey="n" class="tool-spacer" title="3.2. AppStream Catalog YAML" href="sect-AppStream-YAML.html"><span class="next-icon">→</span></a></span></div></div></div></div><div id="_fixed-header-wrap" class="inactive"><div id="_fixed-header"><div class="crumbs"><a class="book-link" href="index.html" title="AppStream"><span class="book-icon">AppStream</span></a><span> › </span><a class="crumb" href="chap-CatalogData.html">Catalog Metadata</a></div><div class="buttons"><a class="top-button button" href="#">Top</a><div class="button"><a accesskey="p" class="tool-spacer" title="2.17. Runtime" href="sect-Metadata-Runtime.html"><span class="prev-icon">←</span></a><a accesskey="n" class="tool-spacer" title="3.2. AppStream Catalog YAML" href="sect-AppStream-YAML.html"><span class="next-icon">→</span></a></div><div class="clearme"></div></div><div class="clearme"></div></div></div><div id="_content" class=""><div class="documentation"><div class="chapter" id="chap-CatalogData"><div class="titlepage"><div><div class="version-info">Applies to  <span class="productname">AppStream</span> <span class="productnumber">1.0</span></div><div><h1 class="title"><span class="number">3 </span><span xmlns:dm="urn:x-suse:ns:docmanager" class="name">Catalog Metadata</span> <a title="Permalink" class="permalink" href="chap-CatalogData.html">#</a></h1></div></div></div><div class="line"><div class="toc"><dl><dt><span class="section"><a href="chap-CatalogData.html#sect-AppStream-XML"><span class="number">3.1 </span><span class="name">AppStream Catalog XML</span></a></span></dt><dt><span class="section"><a href="sect-AppStream-YAML.html"><span class="number">3.2 </span><span class="name">AppStream Catalog YAML</span></a></span></dt><dt><span class="section"><a href="sect-AppStream-IconCache.html"><span class="number">3.3 </span><span class="name">Icon Cache</span></a></span></dt></dl></div></div><p>
		Additionally to the metainfo files shipped by upstream projects, AppStream also provides an XML and YAML format
		to make information about not installed software components known to the system.
	</p><p>
		This chapter documents this catalog metadata format and icon cache used on the client side.
	</p><div class="sect1" id="sect-AppStream-XML"><div class="titlepage"><div><div><h2 class="title" id="sect-AppStream-XML"><span class="number">3.1 </span><span xmlns:dm="urn:x-suse:ns:docmanager" class="name">AppStream Catalog XML</span> <a title="Permalink" class="permalink" href="chap-CatalogData.html#sect-AppStream-XML">#</a></h2></div></div></div><div class="sect2" id="spec-asxml-introduction"><div class="titlepage"><div><div><h3 class="title" id="spec-asxml-introduction"><span class="number">3.1.1 </span><span xmlns:dm="urn:x-suse:ns:docmanager" class="name">Introduction</span> <a title="Permalink" class="permalink" href="chap-CatalogData.html#spec-asxml-introduction">#</a></h3></div></div></div><p>
			AppStream catalog XML files are text files describing all available software components a software repository (usually
			from a Linux distributor) offers for installation.
			The XML files might be compressed with GZip.
		</p></div><div class="sect2" id="spec-asxml-filenaming"><div class="titlepage"><div><div><h3 class="title" id="spec-asxml-filenaming"><span class="number">3.1.2 </span><span xmlns:dm="urn:x-suse:ns:docmanager" class="name">File naming and location</span> <a title="Permalink" class="permalink" href="chap-CatalogData.html#spec-asxml-filenaming">#</a></h3></div></div></div><p>
			The XML files must have a unique name, which is usually the distribution's name and version, combined with the name of the repository/origin.
			For example in Debian 8 (Jessie), the filename for the main repository component would be <code class="filename">debian-jessie-main.xml.gz</code>.
			For Fedora 20 (Heisenbug) updates it would be <code class="filename">fedora-20-updates.xml.gz</code>.
			3rd-party repositories use a vendor name and repository-name combination, for example Ubuntu PPAs might get <code class="filename">ppa-ubuntu12.04-username-foobar.xml</code>.
		</p><p>
			There are two valid locations to store AppStream XML data. <code class="filename">/usr/share/swcatalog/xml</code> stores all AppStream data which
			has been installed via software packages, while <code class="filename">/var/lib/swcatalog/xml</code> stores application data which was downloaded
			by the package manager or placed there by other tools (for example, Limba).
			The <code class="filename">/var/cache/swcatalog/xml</code> location however can be used for any data that was locally generated from other sources.
			The XML files can either be plain files or be compressed with gzip. It is always a good idea to compress the files, because they tend to become
			quite large.
		</p><div id="id-1.4.4.3.4" class="admonition important normal"><img class="symbol" alt="Important" title="Important" src="static/images/icon-important.png" /><h6>Important: Legacy Path</h6><p>
				Prior to version 1.0, AppStream tools scanned the paths <code class="filename">/usr/share/app-info/(xml|xmls)</code> and <code class="filename">/var/lib/app-info/(xml|xmls)</code> path for legacy
				compatibility as well.  Legacy path support was dropped in version 1.0. The old locations should not be used anymore. The modern locations are supported by both the AppStream 1.x as well as AppStream 0.16.x series.
			</p></div></div><div class="sect2" id="spec-asxml-general"><div class="titlepage"><div><div><h3 class="title" id="spec-asxml-general"><span class="number">3.1.3 </span><span xmlns:dm="urn:x-suse:ns:docmanager" class="name">General XML structure</span> <a title="Permalink" class="permalink" href="chap-CatalogData.html#spec-asxml-general">#</a></h3></div></div></div><p>
			The XML starts with a <code class="code">&lt;components&gt;</code> tag as the root element. It has all the
			<code class="code">&lt;component&gt;</code> tags of different <code class="literal">type</code>s as children.
		</p><p>
			Data to fill the different component elements is usually taken from their <a class="ulink" href="https://specifications.freedesktop.org/desktop-entry-spec/latest/" target="_blank">Desktop files<span class="ulink-url"> (https://specifications.freedesktop.org/desktop-entry-spec/latest/)</span></a>
			and package data. However, if an upstream project ships metainfo files (see <a class="xref" href="chap-Metadata.html" title="Chapter 2. Upstream Metadata">Chapter 2, <em>Upstream Metadata</em></a>),
			values defined there should override data from any other source.
		</p><p>
			All child elements of the <code class="code">&lt;components&gt;</code> element, no matter of which type they are, must at least have
			an <code class="literal">id</code>, <code class="literal">name</code>, <code class="literal">summary</code> and <code class="literal">pkgname</code> tag.
			For applications, a <code class="literal">icon</code> tag is also required.
		</p><p>
			The <code class="code">&lt;components&gt;</code> root node has these properties, where the first two are required:
		</p><div class="variablelist"><dl class="variablelist"><dt id="id-1.4.4.4.6.1"><span class="term">version</span></dt><dd><p>
					This property declares the AppStream spec version this file is based on (currently 0.14). The property is required.
				</p></dd><dt id="id-1.4.4.4.6.2"><span class="term">origin</span></dt><dd><p>
					Defines the repository ID this AppStream XML file belongs to. This usually matches the filename without extension (see the explanation on how to pick a good filename above).
					It is also used to associate the right cached icons with AppStream metadata. This property is required.
				</p></dd><dt id="id-1.4.4.4.6.3"><span class="term">media_baseurl</span></dt><dd><p>
					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.
				</p></dd><dt id="id-1.4.4.4.6.4"><span class="term">architecture</span></dt><dd><p>
					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. This property is optional.
				</p></dd></dl></div></div><div class="sect2" id="spec-asxml-tags"><div class="titlepage"><div><div><h3 class="title" id="spec-asxml-tags"><span class="number">3.1.4 </span><span xmlns:dm="urn:x-suse:ns:docmanager" class="name">Valid tags for all component types</span> <a title="Permalink" class="permalink" href="chap-CatalogData.html#spec-asxml-tags">#</a></h3></div></div></div><p>
			These tags can be applied to every component type (application, component, font, inputmethod) which
			is described in the AppStream metadata.
		</p><p>
			Additionally to the <code class="literal">type</code> property, every <code class="literal">&lt;component/&gt;</code> tag in AppStream catalog data
			may have a <code class="literal">priority</code> property, defining the priority of this specific metadata over other metadata from different
			AppStream XML files (for example, from a different repository) which have the same component-id. The value of this tag is an integer, if the
			property is missing, a value of <code class="code">"0"</code> is assumed.
		</p><p>
			In order to <span class="emphasis"><em>merge</em></span> metadata, each component in catalog data may also have a <code class="literal">merge</code> property, assuming the
			values <code class="code">append</code>, <code class="code">replace</code> or <code class="code">remove-component</code>. If the value is <code class="code">append</code>, all data this component describes will be appended
			to data of the component with the same ID. If the value is <code class="code">replace</code> the fields of the target component will be replaced with the
			ones present in the merge component. If the merge type is <code class="code">remove-component</code>, the entore component matching the ID of the merge-component should
			be removed from the metadata pool.
			Merge-components with a higher priority take precedence. If a component has a <code class="literal">merge</code> property, the only tag that must
			be present for it is the <code class="code">&lt;id/&gt;</code> tag, any other metadata is optional.
		</p><div class="variablelist"><dl class="variablelist"><dt id="tag-ct-component-id"><span class="term">&lt;id/&gt;</span> <a title="Permalink" class="permalink" href="chap-CatalogData.html#tag-ct-component-id">#</a></dt><dd><p>
					The <code class="code">&lt;id/&gt;</code> tag is a short unique and usually lower-cases identifier for the component.
					Depending on the component's type, different naming conventions apply.
				</p></dd><dt id="tag-ct-pkgname"><span class="term">&lt;pkgname/&gt;</span> <a title="Permalink" class="permalink" href="chap-CatalogData.html#tag-ct-pkgname">#</a></dt><dd><p>
						The name of the package which needs to be installed in order to make this component available on the system.
					</p><p>
						This tag can be defined multiple times, if a component is split across multiple packages.
					</p><div id="id-1.4.4.5.5.2.2.3" class="admonition important normal"><img class="symbol" alt="Important" title="Important" src="static/images/icon-important.png" /><h6>Important</h6><p>
							The preferred way is to create metapackages containing the component metadata, and referencing them
							from the catalog metadata, and not to use multiple <code class="literal">pkgname</code> tags.
							They should only be used multiple times as a workaround or if there is no sensible way of creating a
							matching metapackage.
						</p></div></dd><dt id="tag-ct-source_pkgname"><span class="term">&lt;source_pkgname/&gt;</span> <a title="Permalink" class="permalink" href="chap-CatalogData.html#tag-ct-source_pkgname">#</a></dt><dd><p>
						This optional tag is used to specify the source package the binary package this component belongs to was built from.
					</p><p>
						The tag can be used by software center applications to group components. It is otherwise useful for the distributor
						to assign components to a source package and to fetch additional information about a package from the web.
					</p></dd><dt id="tag-ct-name"><span class="term">&lt;name/&gt;</span> <a title="Permalink" class="permalink" href="chap-CatalogData.html#tag-ct-name">#</a></dt><dd><p>
						A human-readable name for this software.
					</p><p>
						In case of a component of type <code class="literal">desktop-application</code>, the application name as defined in the application's
						<a class="ulink" href="https://specifications.freedesktop.org/desktop-entry-spec/latest/" target="_blank">desktop file<span class="ulink-url"> (https://specifications.freedesktop.org/desktop-entry-spec/latest/)</span></a> is used.
					</p></dd><dt id="tag-ct-project_license"><span class="term">&lt;project_license/&gt;</span> <a title="Permalink" class="permalink" href="chap-CatalogData.html#tag-ct-project_license">#</a></dt><dd><p>
						The <code class="code">&lt;project_license/&gt;</code> tag is indicating the license of the component.
						It should be a <a class="ulink" href="https://spdx.org/specifications" target="_blank">SPDX license expression<span class="ulink-url"> (https://spdx.org/specifications)</span></a>.
						A full list of recognized licenses and their identifiers can be found at the
						<a class="ulink" href="https://spdx.org/licenses/" target="_blank">SPDX OpenSource License Registry<span class="ulink-url"> (https://spdx.org/licenses/)</span></a>.
					</p><p>
						You can find more information about this tag at the metainfo description for <a class="xref" href="chap-Metadata.html#tag-project_license">&lt;project_license/&gt;</a>.
					</p></dd><dt id="tag-ct-summary"><span class="term">&lt;summary/&gt;</span> <a title="Permalink" class="permalink" href="chap-CatalogData.html#tag-ct-summary">#</a></dt><dd><p>
						The tag contains a short summary of the purpose and function of this component. In case the component is of
						type <code class="literal">desktop</code>, it is usually taken from a Desktop file,
						if the application does not ship an upstream metadata file.
					</p><p>
						For more information about this tag, take a look at the tag's definition at <a class="xref" href="chap-Metadata.html#tag-summary">&lt;summary/&gt;</a>.
					</p></dd><dt id="tag-ct-description"><span class="term">&lt;description/&gt;</span> <a title="Permalink" class="permalink" href="chap-CatalogData.html#tag-ct-description">#</a></dt><dd><p>
						A long description of the component. It is usually taken from the package descriptions or metainfo files, if they were provided.
						The description might use markup. Right now, only paragraph, ordered list and unordered list are supported.
						An example description element might look like this:
						</p><div class="verbatim-wrap highlight XML"><pre class="programlisting">&lt;description&gt;
  &lt;p&gt;
   Power Statistics is a program used to view historical and current battery
   information and will show programs running on your computer using power.
  &lt;/p&gt;
  &lt;p&gt;Example list:&lt;/p&gt;
  &lt;ul&gt;
   &lt;li&gt;First item&lt;/li&gt;
   &lt;li&gt;Second item&lt;/li&gt;
  &lt;/ul&gt;
  &lt;p&gt;
  You probably only need to install this application if you are having problems
  with your laptop battery, or are trying to work out what programs are using
  significant amounts of power.
  &lt;/p&gt;
&lt;/description&gt;</pre></div><p>
					</p><p>
						As opposed to the by-paragraph translation used in metainfo files, this tag is translated "as a whole", meaning that the
						<code class="literal">&lt;description/&gt;</code> tag itself has a language property and contains the translated paragraphs for the given language.
						This allows faster parsing of the Appstream XML file, and does not increase it's size much, as long as it is compressed.
					</p><p>
						For more information about this tag, take a look at the tag's definition at <a class="xref" href="chap-Metadata.html#tag-description">&lt;description/&gt;</a>.
					</p></dd><dt id="tag-ct-url"><span class="term">&lt;url/&gt;</span> <a title="Permalink" class="permalink" href="chap-CatalogData.html#tag-ct-url">#</a></dt><dd><p>
						Defines URLs for this component. This tag can be present multiple times.
					</p><p>
						For a list of possible url types and what they are expected to do,
						take a look at the tag's description at <a class="xref" href="chap-Metadata.html#tag-url">&lt;url/&gt;</a>.
					</p></dd><dt id="tag-ct-project_group"><span class="term">&lt;project_group/&gt;</span> <a title="Permalink" class="permalink" href="chap-CatalogData.html#tag-ct-project_group">#</a></dt><dd><p>
						The <code class="code">&lt;project_group&gt;</code> tag identifies a project with a specific upstream umbrella project.
						Known values include <code class="literal">GNOME, KDE, XFCE, LXDE, Mozilla</code> and <code class="literal">MATE</code>, although other umbrella projects
						like <code class="literal">Yorba</code> would make sense too.
					</p><div id="id-1.4.4.5.5.9.2.2" class="admonition note normal"><img class="symbol" alt="Note" title="Note" src="static/images/icon-note.png" /><h6>Note</h6><p>
							Components should only identify with an umbrella project if you use all their infrastructure and policies, for instance
							string freezes dates, bugtracker and source control instance.
						</p></div></dd><dt id="tag-ct-icon"><span class="term">&lt;icon/&gt;</span> <a title="Permalink" class="permalink" href="chap-CatalogData.html#tag-ct-icon">#</a></dt><dd><p>
						The <code class="code">&lt;icon/&gt;</code> tag describes the component icon. It is mostly used for GUI applications (component-type <code class="literal">desktop-application</code>).
						It can be of the type <code class="literal">stock</code>, <code class="literal">cached</code>, <code class="literal">local</code>,
						or <code class="literal">url</code>.
					</p><p>
						<code class="literal">stock</code> icons are loaded from stock. The icon name should never include any file-extension or path.
					</p><p>
						<code class="literal">cached</code> icons are loaded from the AppStream icon cache. The icon tag should contain the icon file name, including its
						extension. It must not contain a full or relative path to the icon file.
						This icon type may have <code class="literal">width</code> and <code class="literal">height</code> properties.
						If targeting a hi-DPI screen, this icon type may have a <code class="literal">scale</code> property.
					</p><p>
						<code class="literal">local</code> icons are reserved for AppStream data installed by local applications or via 3rd-party application installers.
						They should specify a full file path.
						This icon type may have <code class="literal">width</code> and <code class="literal">height</code> properties.
						If targeting a hi-DPI screen, this icon type may have a <code class="literal">scale</code> property.
					</p><p>
						<code class="literal">remote</code> icons loaded from a remote URL. Currently, only HTTP urls are supported.
						This icon type should have <code class="literal">width</code> and <code class="literal">height</code> properties.
						If targeting a hi-DPI screen, this icon type may have a <code class="literal">scale</code> property.
					</p><p>
						If specified, the <code class="literal">scale</code> property is defined as in the
						<a class="ulink" href="https://specifications.freedesktop.org/icon-theme-spec/latest/#definitions" target="_blank">Freedesktop Icon Theme Specification<span class="ulink-url"> (https://specifications.freedesktop.org/icon-theme-spec/latest/#definitions)</span></a>.
						It’s an integer value ≥1 indicating how many pixels in the image represent a logical pixel on the display, in each dimension.
						This allows icons for hi-DPI screens to be displayed at the same logical size as on lower resolution screens, but without upscaling artifacts.
					</p><p>
						Examples of the different methods to specify an icon:
					</p><div class="verbatim-wrap highlight XML"><pre class="programlisting">&lt;icon type="stock"&gt;gimp&lt;/icon&gt;
&lt;icon type="cached"&gt;firefox.png&lt;/icon&gt;
&lt;icon type="cached" width="128" height="128" scale="2"&gt;firefox.png&lt;/icon&gt;
&lt;icon type="remote" width="64" height="64"&gt;https://example.com/icons/foobar.png&lt;/icon&gt;
&lt;icon type="local" width="64" height="64"&gt;/usr/share/pixmaps/foobar.png&lt;/icon&gt;</pre></div><p>
						Multiple <code class="code">&lt;icon/&gt;</code> tags might be combined for one application, for example to define a <code class="literal">stock</code> icon
						and a <code class="literal">cached</code> icon.
						Software-Centers should always prefer the stock icon, if it is available, and fall back to the other icon types if they can not find it.
						The <span class="emphasis"><em>libappstream</em></span> library makes it easy to do that.
					</p><p>
						The AppStream library will prefer <code class="literal">cached</code> over <code class="literal">local</code> over <code class="literal">remote</code>
						icons when setting the non-stock icon for the application.
					</p></dd><dt id="tag-ct-categories"><span class="term">&lt;categories/&gt;</span> <a title="Permalink" class="permalink" href="chap-CatalogData.html#tag-ct-categories">#</a></dt><dd><p>
						This tag can contain one or more <code class="code">&lt;category&gt;</code> tags, describing the categories this component
						is located in. This tag is usually applied to components of type <code class="literal">desktop-application</code>, although it might be used by others later.
						This data is usually taken from Desktop files, a list of categories can be found in the
						<a class="ulink" href="https://specifications.freedesktop.org/menu-spec/latest/category-registry.html" target="_blank">Freedesktop menu spec<span class="ulink-url"> (https://specifications.freedesktop.org/menu-spec/latest/category-registry.html)</span></a>.
						Example:
					</p><div class="verbatim-wrap highlight XML"><pre class="programlisting">&lt;categories&gt;
    &lt;category&gt;Science&lt;/category&gt;
    &lt;category&gt;Network&lt;/category&gt;
    &lt;category&gt;Telephony&lt;/category&gt;
&lt;/categories&gt;</pre></div><div id="id-1.4.4.5.5.11.2.3" class="admonition note normal"><img class="symbol" alt="Note" title="Note" src="static/images/icon-note.png" /><h6>Note: Deprecated Tags</h6><p>
							The tag <code class="code">&lt;appcategories&gt;</code> with its <code class="code">&lt;appcategory&gt;</code> child elements is deprecated API.
							AppStream parsers should handle these tags just like the <code class="literal">category</code> tags, there is no difference except for the name.
						</p></div></dd><dt id="tag-ct-keywords"><span class="term">&lt;keywords/&gt;</span> <a title="Permalink" class="permalink" href="chap-CatalogData.html#tag-ct-keywords">#</a></dt><dd><p>
						This tag can contain one or more <code class="code">&lt;keyword&gt;</code> tags, describing keywords for the component,
						to make it easier to find in a software center.
					</p><p>
						This tag behaves like the <a class="xref" href="chap-Metadata.html#tag-keywords">&lt;keywords/&gt;</a> tag used in metainfo files, but is translated "as a whole",
						unlike its metainfo counterpart that has individual keywords translated. This means that the <code class="literal">&lt;keywords/&gt;</code> tag
						itself has a language property and contains only the translated keywords for the given language.
					</p><p>
						In case of type <code class="literal">desktop-application</code> components, this data is taken from .desktop files. For <code class="literal">addon</code>
						components, the upstream metadata file usually provides this tag.
					</p><p>
						Example:
					</p><div class="verbatim-wrap highlight XML"><pre class="programlisting">&lt;keywords&gt;
  &lt;keyword&gt;IDE&lt;/keyword&gt;
  &lt;keyword&gt;development&lt;/keyword&gt;
  &lt;keyword&gt;programming&lt;/keyword&gt;
&lt;/keywords&gt;
&lt;keywords xml:lang="de"&gt;
  &lt;keyword&gt;IDE&lt;/keyword&gt;
  &lt;keyword&gt;entwicklung&lt;/keyword&gt;
  &lt;keyword&gt;programmierung&lt;/keyword&gt;
&lt;/keywords&gt;</pre></div></dd><dt id="tag-ct-screenshots"><span class="term">&lt;screenshots/&gt;</span> <a title="Permalink" class="permalink" href="chap-CatalogData.html#tag-ct-screenshots">#</a></dt><dd><p>
						This tag can contain one or more <code class="code">&lt;screenshot&gt;</code> tags, describing screenshots which are available for
						the software. A screenshot tag my have the attribute <code class="code">type="default"</code>, marking it as the software's default screenshot,
						which primarily represents it in a software center.
					</p><p>
						The <code class="literal">screenshots</code> tag is described for metainfo files in <a class="xref" href="chap-Metadata.html#tag-screenshots">&lt;screenshots/&gt;</a>. In catalog metadata, the tag
						has the exact same format as in metainfo files.
						The metadata generator may add an arbitrary number of resized thumbnails for <code class="literal">image</code> type screenshots though.
					</p><p>
						Every static-image <code class="code">&lt;screenshot&gt;</code> is defined by several images of different sizes.
						All images should have their width and hight set as arguments. Also, one of the images should be marked as <code class="code">type="source"</code>,
						indicating that it is the unscaled version of the screenshot.
						Images of <code class="code">type="thumbnail"</code> define thumbnails of the screenshot.
					</p><p>
						The metadata generator should scale the source image down to several thumbnails useful for the client to load.
						The recommended widths for thumbnail images are:
					</p><div class="itemizedlist"><ul class="itemizedlist"><li class="listitem"><p><span class="emphasis"><em>752</em></span> (large)</p></li><li class="listitem"><p><span class="emphasis"><em>624</em></span> (normal)</p></li><li class="listitem"><p><span class="emphasis"><em>112</em></span> (small)</p></li><li class="listitem"><p><span class="emphasis"><em>1504</em></span> (large, HiDPI)</p></li><li class="listitem"><p><span class="emphasis"><em>1248</em></span> (normal, HiDPI)</p></li><li class="listitem"><p><span class="emphasis"><em>224</em></span> (small, HiDPI)</p></li></ul></div><p>
						In order to support HiDPI screens, the thumbnails should also be available in their bigger sizes. A metadata generator should, however, never attempt
						to scale up a smaller image to a larger size, and just ship the smaller sizes instead.
						When scaling images to the respective thumbnail width, the image aspect ratio must be preserved, padding, cropping or stretching should not happen.
					</p><p>
						Optionally, a screenshot can contain a <code class="code">&lt;caption&gt;</code> tag, describing the screenshot's caption. This is usually what the user can see
						on the image shown. The tag is translatable.
					</p><p>
						For <code class="code">&lt;screenshot&gt;</code> tags that contain <code class="literal">video</code> elements, a catalog metadata generator may impose any restrictions to them,
						including completely removing them from the output, imposing filesize limits, etc.
						Upstream metainfo files should not rely on the videos being present and must always have a static screenhot for the software component as well.
					</p><p>
						Every image or video should have a full remote url set, usually pointing to a cache of images maintained by the repository vendor.
						Example:
					</p><div class="verbatim-wrap highlight XML"><pre class="programlisting">&lt;screenshots&gt;
  &lt;screenshot type="default"&gt;
    &lt;caption&gt;FooBar showing kitchen-sink functionality.&lt;/caption&gt;
    &lt;caption xml:lang="de"&gt;FooBar beim Ausführen der Spühlbecken-Funktion.&lt;/caption&gt;
    &lt;image type="source" width="800" height="600"&gt;https://www.example.org/en_US/main.png&lt;/image&gt;
    &lt;image type="thumbnail" width="752" height="423"&gt;https://www.example.org/en_US/main-large.png&lt;/image&gt;
    &lt;image type="thumbnail" width="112" height="63"&gt;https://www.example.org/en_US/main-small.png&lt;/image&gt;
  &lt;/screenshot&gt;
  &lt;screenshot&gt;
    &lt;video container="matroska" codec="av1" width="800" height="600"&gt;https://www.example.org/en_US/screencast.mkv&lt;/video&gt;
  &lt;/screenshot&gt;
  &lt;screenshot&gt;
     ....
  &lt;/screenshot&gt;
&lt;/screenshots&gt;</pre></div></dd><dt id="tag-ct-compulsory_for_desktop"><span class="term">&lt;compulsory_for_desktop/&gt;</span> <a title="Permalink" class="permalink" href="chap-CatalogData.html#tag-ct-compulsory_for_desktop">#</a></dt><dd><p>
						The <code class="code">&lt;compulsory_for_desktop&gt;</code> tag indicates that the component which the metadata belongs to is essential for the
						functionality of the defined desktop environment.
					</p><p>
						This tag is described in detail at <a class="xref" href="chap-Metadata.html#tag-compulsory_for_desktop">&lt;compulsory_for_desktop/&gt;</a>.
					</p></dd><dt id="tag-ct-provides"><span class="term">&lt;provides/&gt;</span> <a title="Permalink" class="permalink" href="chap-CatalogData.html#tag-ct-provides">#</a></dt><dd><p>
						This tag is described in detail at <a class="xref" href="chap-Metadata.html#sect-Metadata-GenericComponent" title="2.1. Generic Component">Section 2.1, “Generic Component”</a>.
					</p><p>
						Distributors and software repository vendors must ensure that all things described in this tag are present in the package referenced in
						the associated <code class="literal">pkgname</code> tag (or in dependencies of it).
					</p></dd><dt id="tag-ct-developer"><span class="term">&lt;developer/&gt;</span> <a title="Permalink" class="permalink" href="chap-CatalogData.html#tag-ct-developer">#</a></dt><dd><p>
					The <code class="code">&lt;developer/&gt;</code> tag as described in the specification for a generic component. See <a class="xref" href="chap-Metadata.html#tag-developer">&lt;developer/&gt;</a> for more information.
				</p></dd><dt id="tag-ct-launchable"><span class="term">&lt;launchable/&gt;</span> <a title="Permalink" class="permalink" href="chap-CatalogData.html#tag-ct-launchable">#</a></dt><dd><p>
						This tag follows the same schema as described for metainfo files in <a class="xref" href="chap-Metadata.html#tag-launchable">&lt;launchable/&gt;</a>.
					</p></dd><dt id="tag-ct-releases"><span class="term">&lt;releases/&gt;</span> <a title="Permalink" class="permalink" href="chap-CatalogData.html#tag-ct-releases">#</a></dt><dd><p>
						The <code class="literal">releases</code> tag and its <code class="literal">release</code> children are structured as described in <a class="xref" href="sect-Metadata-Releases.html" title="2.2. Release Information">Section 2.2, “Release Information”</a>.
					</p><p>
						Each <code class="literal">release</code> tag may have a <code class="literal">description</code> tag as child, containing a brief description of what is new in the release.
						The <code class="literal">description</code> tag is structured as described in <a class="xref" href="chap-CatalogData.html#tag-ct-description">&lt;description/&gt;</a>. This also applies to its translation rules.
					</p><p>
						The AppStream catalog XML generator may shorten overlong lists of releases to a smaller list, for example of 4 <code class="literal">release</code> tags.
						It may also convert ISO 8601 <code class="literal">date</code> properties of the metainfo file into an UNIX timestamp <code class="literal">timestamp</code> property.
						It should avoid generating metadata containing both properties on a <code class="literal">release</code> tag.
					</p><p>
						If a <a class="xref" href="chap-Metadata.html#tag-releases">&lt;releases/&gt;</a> tag in a metainfo file references an <code class="literal">external</code> release description, the release description should
						be read either from the release file provided locally, or, if possible and provided, be downloaded from the URL referenced in the component's <code class="literal">releases</code>
						tag.
					</p><p>
						Example for a valid releases tag:
					</p><div class="verbatim-wrap highlight XML"><pre class="programlisting">&lt;releases&gt;
  &lt;release version="1.8" timestamp="1424116753"&gt;
    &lt;description&gt;
      &lt;p&gt;This stable release fixes the following bug:&lt;/p&gt;
      &lt;ul&gt;
        &lt;li&gt;CPU no longer overheats when you hold down spacebar&lt;/li&gt;
      &lt;/ul&gt;
    &lt;/description&gt;
    &lt;size type="download"&gt;12345678&lt;/size&gt;
    &lt;size type="installed"&gt;42424242&lt;/size&gt;
  &lt;/release&gt;
  &lt;release version="1.2" timestamp="1397253600" /&gt;
  &lt;release version="1.0" timestamp="1345932000" /&gt;
&lt;/releases&gt;</pre></div><p>
						In case a <code class="code">&lt;release/&gt;</code> tag has a <code class="code">&lt;description/&gt;</code> tag as parameter, describing the new release briefly, distributors are encouraged to provide 2-4
						<code class="code">&lt;release/&gt;</code> release tags for every component. If no description is provided, one tag is enough.
					</p></dd><dt id="tag-ct-languages"><span class="term">&lt;languages/&gt;</span> <a title="Permalink" class="permalink" href="chap-CatalogData.html#tag-ct-languages">#</a></dt><dd><p>
						This tag gives information about the translations a component provides, and to which extent the software is translated.
					</p><p>
						The tag is allowed to only occur once per component, and contains multiple <code class="code">&lt;lang/&gt;</code> child nodes, which have
						a <a class="ulink" href="https://www.gnu.org/software/gettext/manual/html_node/Language-Codes.html" target="_blank">language code<span class="ulink-url"> (https://www.gnu.org/software/gettext/manual/html_node/Language-Codes.html)</span></a> as value.
						Each <code class="code">&lt;lang/&gt;</code> node may have a <code class="literal">percentage</code> property, which describes the percentage value to which
						a component has been translated.
					</p><p>
						The language data is expected to be extracted by the AppStream XML generator, and is not provided upstream. Generators may obtain the
						information from processing GNU Gettext files, which should cover most translation methods.
					</p><p>
						Tag example:
					</p><div class="verbatim-wrap highlight XML"><pre class="programlisting">&lt;languages&gt;
  &lt;lang percentage="96"&gt;gu&lt;/lang&gt;
  &lt;lang percentage="94"&gt;ca@valencia&lt;/lang&gt;
  &lt;lang percentage="91"&gt;de&lt;/lang&gt;
  &lt;lang percentage="93"&gt;eo&lt;/lang&gt;
&lt;/languages&gt;</pre></div></dd><dt id="tag-ct-bundle"><span class="term">&lt;bundle/&gt;</span> <a title="Permalink" class="permalink" href="chap-CatalogData.html#tag-ct-bundle">#</a></dt><dd><p>
						The optional <code class="literal">bundle</code> tag indicates that the described software is available as a software bundle via a
						3rd-party application installer. The value of this tag is an identification string for the bundle.
					</p><p>
						Software centers may use the information of this tag to offer the user to install the software
						from 3rd-party sources, or just update an already installed software automatically via the normal update procedure.
						The <code class="literal">bundle</code> tag can coexist with the <code class="literal">pkgname</code> tag, in case a component is available from
						multiple sources.
					</p><p>
						The <code class="literal">type</code> property of this tag indicates which 3rd-party software installation solution the bundle belongs to.
						Currently supported solutions are:
						</p><div class="itemizedlist"><ul class="itemizedlist"><li class="listitem"><p><code class="code">package</code> - For distribution package names.</p></li><li class="listitem"><p><code class="code">limba</code> - For <a class="ulink" href="https://people.freedesktop.org/~mak/limba/" target="_blank">Limba Project<span class="ulink-url"> (https://people.freedesktop.org/~mak/limba/)</span></a> bundles.</p></li><li class="listitem"><p><code class="code">flatpak</code> - For <a class="ulink" href="https://flatpak.org/" target="_blank">Flatpak<span class="ulink-url"> (https://flatpak.org/)</span></a> bundles.</p></li><li class="listitem"><p><code class="code">appimage</code> - For <a class="ulink" href="https://appimage.org/" target="_blank">AppImageKit<span class="ulink-url"> (https://appimage.org/)</span></a> bundles.</p></li><li class="listitem"><p><code class="code">snap</code> - For <a class="ulink" href="https://snapcraft.io/" target="_blank">Snappy<span class="ulink-url"> (https://snapcraft.io/)</span></a> snap bundles.</p></li><li class="listitem"><p><code class="code">tarball</code> - For plain and possibly compressed tarballs.</p></li><li class="listitem"><p><code class="code">cabinet</code> - For cabinet firmware deployments.</p></li><li class="listitem"><p><code class="code">linglong</code> - For <a class="ulink" href="https://linglong.dev/" target="_blank">Linglong<span class="ulink-url"> (https://linglong.dev/)</span></a> bundles.</p></li><li class="listitem"><p><code class="code">sysupdate</code> - For <a class="ulink" href="https://www.freedesktop.org/software/systemd/man/latest/systemd-sysupdate.html" target="_blank">systemd-sysupdate<span class="ulink-url"> (https://www.freedesktop.org/software/systemd/man/latest/systemd-sysupdate.html)</span></a> bundles.</p></li></ul></div><p>
					</p><p>
						Example:
					</p><div class="verbatim-wrap highlight XML"><pre class="programlisting">&lt;bundle type="limba"&gt;foobar-1.0.2&lt;/bundle&gt;</pre></div></dd><dt id="tag-ct-suggests"><span class="term">&lt;suggests/&gt;</span> <a title="Permalink" class="permalink" href="chap-CatalogData.html#tag-ct-suggests">#</a></dt><dd><p>
						The optional <code class="literal">suggests</code> tag provides suggestions of other software made by this component.
						It follows the same schema as described for metainfo files in <a class="xref" href="chap-Metadata.html#tag-suggests">&lt;suggests/&gt;</a>.
					</p><p>
						Additionally to the <code class="literal">upstream</code> type allowed for metainfo files, the catalog data also allows a
						<code class="literal">heuristic</code> type, which is added by automatic recommendation services, and might be based on the user's
						preferences. It is commonly injected into existing metadata via a <code class="literal">merge</code> pseudo-component.
					</p><p>
						Example:
					</p><div class="verbatim-wrap highlight XML"><pre class="programlisting">&lt;suggests type="upstream"&gt;
  &lt;id&gt;org.kde.gwenview.desktop&lt;/id&gt;
  &lt;id&gt;org.inkscape.Inkscape&lt;/id&gt;
&lt;/suggests&gt;
&lt;suggests type="heuristic"&gt;
  &lt;id&gt;org.gimp.gimp.desktop&lt;/id&gt;
&lt;/suggests&gt;</pre></div></dd><dt id="tag-ct-content_rating"><span class="term">&lt;content_rating/&gt;</span> <a title="Permalink" class="permalink" href="chap-CatalogData.html#tag-ct-content_rating">#</a></dt><dd><p>
						This optional tag follows the same schema as described for metainfo files in <a class="xref" href="chap-Metadata.html#tag-content_rating">&lt;content_rating/&gt;</a>.
					</p></dd><dt id="tag-ct-agreement"><span class="term">&lt;agreement/&gt;</span> <a title="Permalink" class="permalink" href="chap-CatalogData.html#tag-ct-agreement">#</a></dt><dd><p>
						This optional tag follows the same schema as described for metainfo files in <a class="xref" href="chap-Metadata.html#tag-agreement">&lt;agreement/&gt;</a>, with the exception
						of <code class="literal">description</code> tags in its <code class="literal">agreement_section</code> child tags now following the same translation
						rules as the toplevel <a class="xref" href="chap-CatalogData.html#tag-ct-description">&lt;description/&gt;</a> tag in catalog metadata.
					</p></dd></dl></div></div><div class="sect2" id="spec-asxml-example"><div class="titlepage"><div><div><h3 class="title" id="spec-asxml-example"><span class="number">3.1.5 </span><span xmlns:dm="urn:x-suse:ns:docmanager" class="name">Example file</span> <a title="Permalink" class="permalink" href="chap-CatalogData.html#spec-asxml-example">#</a></h3></div></div></div><p>
			This is an example AppStream metadata file:
		</p><div class="verbatim-wrap highlight XML"><pre class="programlisting">
&lt;?xml version="1.0"?&gt;
&lt;components version="0.10"&gt;
  &lt;component type="desktop-application"&gt;
    &lt;id&gt;org.mozilla.Firefox&lt;/id&gt;
    &lt;pkgname&gt;firefox-bin&lt;/pkgname&gt;
    &lt;name&gt;Firefox&lt;/name&gt;
    &lt;name lang="en_GB"&gt;Firefoux&lt;/name&gt;
    &lt;summary&gt;Web browser&lt;/summary&gt;
    &lt;summary lang="fr_FR"&gt;Navigateur web&lt;/summary&gt;
    &lt;project_license&gt;MPL-2.0&lt;/project_license&gt;
    &lt;keywords&gt;
      &lt;keyword&gt;internet&lt;/keyword&gt;
      &lt;keyword&gt;web&lt;/keyword&gt;
      &lt;keyword&gt;browser&lt;/keyword&gt;
      &lt;keyword lang="fr_FR"&gt;navigateur&lt;/keyword&gt;
    &lt;/keywords&gt;
    &lt;icon type="stock"&gt;web-browser&lt;/icon&gt;
    &lt;icon type="cached"&gt;firefox.png&lt;/icon&gt;
    &lt;categories&gt;
      &lt;category&gt;network&lt;/category&gt;
      &lt;category&gt;web&lt;/category&gt;
    &lt;/categories&gt;
    &lt;url type="homepage"&gt;https://www.mozilla.com&lt;/url&gt;
    &lt;screenshots&gt;
      &lt;screenshot type="default"&gt;
        &lt;image type="source" width="800" height="600"&gt;https://www.awesomedistro.example.org/en_US/firefox.desktop/main.png&lt;/image&gt;
        &lt;image type="thumbnail" width="200" height="150"&gt;https://www.awesomedistro.example.org/en_US/firefox.desktop/main-small.png&lt;/image&gt;
      &lt;/screenshot&gt;
    &lt;/screenshots&gt;
    &lt;provides&gt;
      &lt;binary&gt;firefox&lt;/binary&gt;

      &lt;mediatype&gt;text/html&lt;/mediatype&gt;
      &lt;mediatype&gt;text/xml&lt;/mediatype&gt;
      &lt;mediatype&gt;application/xhtml+xml&lt;/mediatype&gt;
      &lt;mediatype&gt;application/vnd.mozilla.xul+xml&lt;/mediatype&gt;
      &lt;mediatype&gt;text/mml&lt;/mediatype&gt;
      &lt;mediatype&gt;application/x-xpinstall&lt;/mediatype&gt;
      &lt;mediatype&gt;x-scheme-handler/http&lt;/mediatype&gt;
      &lt;mediatype&gt;x-scheme-handler/https&lt;/mediatype&gt;
    &lt;/provides&gt;
  &lt;/component&gt;
  &lt;component&gt;
    &lt;id&gt;org.freedesktop.PulseAudio&lt;/id&gt;
    &lt;name&gt;PulseAudio&lt;/name&gt;
    &lt;summary&gt;The PulseAudio sound server&lt;/summary&gt;
    &lt;url type="homepage"&gt;https://www.freedesktop.org/wiki/Software/PulseAudio/&lt;/url&gt;
    &lt;project_license&gt;GPL-2.0+&lt;/project_license&gt;
    &lt;provides&gt;
      &lt;library&gt;libpulse-simple.so.0&lt;/library&gt;
      &lt;library&gt;libpulse.so.0&lt;/library&gt;
      &lt;binary&gt;start-pulseaudio-kde&lt;/binary&gt;
      &lt;binary&gt;start-pulseaudio-x11&lt;/binary&gt;
    &lt;/provides&gt;
    &lt;release version="2.0"/&gt;
  &lt;/component&gt;
  &lt;component type="font"&gt;
    &lt;id&gt;org.linuxlibertine.LinuxLibertine&lt;/id&gt;
    &lt;name&gt;Linux Libertine&lt;/name&gt;
    &lt;summary&gt;Linux Libertine Open fonts&lt;/summary&gt;
    &lt;provides&gt;
      &lt;font&gt;LinLibertine_M.otf&lt;/font&gt;
    &lt;/provides&gt;
  &lt;/component&gt;
  &lt;!-- more components here! --&gt;
&lt;/components&gt;</pre></div></div></div></div></div><div class="page-bottom"><div id="_bottom-navigation"><a class="nav-link" href="sect-AppStream-YAML.html"><span class="next-icon">→</span><span class="nav-label">AppStream Catalog YAML</span></a><a class="nav-link" href="sect-Metadata-Runtime.html"><span class="prev-icon">←</span><span class="nav-label">Runtime</span></a></div></div></div><div id="_inward"></div></div><div id="_footer-wrap"><div id="_footer"><p>©
        2025 
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