This page arranges the same material found in The snapcraft format as a single page.
| Name | Description |
|---|---|
name mandatory |
The identifying name of the snap. Type: string It must start with an ASCII character and can only contain letters in lower case, numbers, and hyphens, and it can’t start or end with a hyphen. The name must be unique if you want to publish to the Snap Store. For help on choosing a name and registering it on the Snap Store, see Registering your app name. Example: my-awesome-app
|
titleoptional |
The canonical title of the application, displayed in the software centre graphical frontends. Type: stringMax length 40 characters. In the legacy Snapcraft syntax (prior to the base key), this key is only available through the passthrough key. Example: My Awesome Application |
base optional |
A snap of type base to be used as the execution environment for this snap. Example: core18
|
version mandatory |
A user facing version to display. Type: string Max len. 32 chars. Needs to be wrapped with single-quotes when the value will be interpreted by the YAML parser as non-string Examples: '1', '1.2', '1.2.3', git (will be replaced by a git describe based version string) |
version-script deprecated |
Deprecated Use snapcraftctl set-version part scriptlet instead. A command to determine the snap’s version string Type: string Runs from the working directory of the source tree root, and prints a version string to the standard output. Replaces the value of the version keyword. The version keyword is still mandatory (but ignored). |
summary mandatory |
Sentence summarising the snap. Type: string Max len. 78 characters, describing the snap in short and simple terms. Example: The super cat generator
|
description mandatory |
Multi-line description of the snap. Type: string A more in-depth look at what your snap does and who may find it most useful. |
type optional |
The type of snap, implicitly set to app if not set.Type: enum For more details, see: gadget, kernel and base |
confinement optional |
Determines if the snap should be restricted in access or not. Type: enum Possible values are strict (for no access outside of declared interfaces through plugs), devmode (for unrestricted access) or classic. For more information, refer to Confinement Examples: strict, or devmode
|
icon optional |
Path to icon image that represents the snap in the snapcraft.io store pages and other graphical store fronts. Note that the desktop menu does not use this icon. It uses the icon in the .desktop file of the application. Type: string It is a relative path to a .png or .svg file from the source tree root. The recommended size is 256x256 pixels. Aspect ratio needs to be 1:1. Image size can vary from 40x40 to 512x512 px and the file size should not be larger than 256 KB.Examples: _package_name_.svg, or snap/gui/logo.png
|
license optional |
A license for the snap in the form of an SPDX expression for the license. In the legacy Snapcraft syntax (not using the base key), this key is only available through the passthrough key. Currently, only SPDX 2.1 expressions are supported, refer snapd/licenses.go at master · snapcore/snapd for accepted expressions. Type: stringExamples: GPL-3.0, MIT, Proprietary
|
grade optional |
Defines the quality grade of the snap. Type: enum Can be either devel (i.e. a development version of the snap, so not to be published to the stable or candidate channels) or stable (i.e. a stable release or release candidate, which can be released to all channels) Example: [stable or devel] |
adopt-info optional |
Incorporate external metadata via the referenced part. Type: string See Using external metadata for more details. |
architectures optional |
List of build and run architectures. Type: list[object] For more details, see Architectures. |
assumes optional |
A list of features that must be supported by the core in order for this snap to install. For example, to make the snap only installable on certain recent version of snapd (like 2.38) you can specify: - snapd2.38. See Snapcraft top-level metadata for other potential values.Type: list[string]
|
passthrough optional |
Attributes to passthrough to snap.yaml without validation from snapcraft. Type: type[object] See Using development features in snapcraft for more details. |
| apps | A map of app-names representing entry points to run for the snap. Type: dict
|
apps.<app-name>
|
The name exposed to run a program inside the snap. Type: dict If <app-name> is the same as name, the program will be invoked as app-name. However, if they differ, the program will be exposed as <snap-name>.<app-name>. |
apps.<app-name>.adapter |
Controls the creation of an env variable wrapper. Type enum Can be one of the following: - none- full (default) Snapcraft normally creates a wrapper holding common environment variables. Disabling this could be useful for minimal base snaps without a shell, and for statically linked binaries with no use for an environment. |
apps. <app-name>. autostart |
The name of the autostart .desktop file. Type: string The desktop file is placed in $SNAP_USER_DATA/.config/autostart, and the application is started using the app’s command wrapper. See Snapcraft parts metadata for further details. |
apps.<app-name>. command
|
The command to run inside the snap when <app-name> is invoked. Type: string The command can be in either a snap runtime’s command path, $SNAP/usr/sbin:$SNAP/usr/bin:$SNAP/sbin:$SNAP/bin, or an executable path relative to $SNAP. If daemon is set, this will be the command to run the service. Only a snap with classic confinement can use a relative path because PATH isn’t modified by a wrapper in classic confinement. See Classic confinement for more details. Examples: app-launch for an executable placed under $SNAP/bin. With classic confinement, bin/app-launch for an executable placed under $SNAP/bin. |
apps.<app-name>.command-chain |
A list of commands to be executed prior to apps.<app-name>.command. Type: string The list is executed, in order, before running the apps.<app-name>.command. See Proposal: support command-chain in apps and hooks for more details. To ensure that the Snapd distribution user running supports this feature, insert the command-chain value to the assumes property. |
apps.<app-name>.common-id |
An identifier to a desktop-id within an external appstream file. Type: string See Using external metadata for more details. |
apps.<app-name>.daemon |
Declares that <app-name> is a system daemon. Type: enum Can be one of the following: - simple: the command is the main process. - oneshot: the configured command will exit after completion - forking: the configured command calls fork() as part of its start-up. The parent process is then expected to exit when start-up is complete - notify: the command configured will send a signal to systemd to indicate that it’s running. |
apps.<app-name>.desktop |
Location of the .desktop file. Type: string A path relative to the prime directory pointing to a desktop file, commonly used to add an application to the launch menu. Snapcraft will take care of the rest. Examples: usr/share/applications/my-app.desktop and share/applications/my-app.desktop
|
apps.<app-name>. environment |
A set of key-value pairs specifying the contents of environment variables. Type: dict Key is the environment variable name; Value is the contents of the environment variable. Example: LANG: C.UTF-8
|
apps.<app-name>. extensions |
Extensions to apply to this application. Type: list[string] Example: [gnome-3-28]
|
apps.<app-name>. plugs |
Plugs for interfaces to connect to. Type: list[string] |
apps.<app-name>. slots |
Slots for interfaces to connect to. Type: list[string] <app-name> will make these slot connections when running in strict confinement only. For interfaces that need attributes, see top-level slots. Example: [home, removable-media, raw-usb] |
apps.<app-name>. stop-command |
The path to a command inside the snap to run to stop the service. Type: string Requires daemon to be set as the snap type. |
apps.<app-name>. post-stop-command |
Runs a command from inside the snap after a service stops Type: string Requires daemon to be set as the snap type. |
apps.<app-name>. stop-timeout |
The length of time to wait before terminating a service. Type: string Time duration units can be 10ns, 10us, 10ms, 10s, 10m. Termination is via SIGTERM (and SIGKILL if that doesn’t work). Requires daemon to be set as the snap type. |
apps.<app-name>. timer |
Schedules when, or how often, to run a service or command. Type: timer string See Timer string format for further details on the required syntax. Requires daemon to be set as the snap type. |
apps.<app-name>. restart-condition |
Condition to restart the daemon under. Type: enum Defaults to on-failure. Other values are [on-failure|on-success|on-abnormal|on-abort|always|never]. Refer to systemd.service manual for details. Requires daemon to be set as the snap type. |
apps.<app-name>. socket |
Maps a daemon’s sockets to services and activates them. Type: dict Requires an activated daemon socket. Requires apps.<app-name>.plugs to declare the network-bind plug. |
apps.<app-name>. socket-mode |
The mode of a socket in octal. Type: integer
|
apps.<app-name>. listen-stream |
The socket abstract name or socket path. Type: string Sockets should go to a map of <socket-name> to objects which specify the listen-stream and (optionally) the socket-mode. TCP socket syntax: \<port\>, [::]:\<port\>, [::1]:\<port\> and 127.0.0.1:\<port\> UNIX socket syntax: $SNAP_DATA/\<path\>, $SNAP_COMMON/<path> and @snap.\<snap name\>.<suffix>
|
apps.<app-name>. passthrough |
<app-name> attributes to pass through to snap.yaml without snapcraft validation. Type: type[object] See Using in-development features for further details. |
plugs optional |
A set of plugs that the snap asserts. Type: dict These plugs apply to all apps and differs from apps.<app-name>.plugs in that the type is in a dict rather than a list format, :(colon) must be postfixed to the interface name and shouldn’t start with -(dash-space) |
plugs. <plug-name> optional |
A set of attributes for a plug Type: dict Example: read attribute for the home interface |
plugs. <plug-name>. <attribute-name> optional |
Value of the attribute Type: string Example: all for read attribute of the home interface |
slots optional |
A set of slots that the snap provides. Type: dict
|
These slots apply to all the apps
|
|
slots. <slot-name> optional |
A set of attributes of the slot Type: dict
|
slots. <slot-name>. <attribute-name> optional |
Value of the attribute Type: dict
|
parts |
A set of independent building blocks. Type: dict These independent building blocks are known as parts, and consist of either code or pre-built packages. |
parts. <part-name> |
The name of the part building block. Type: dict<part-name> represents the specific name of a building block which can be then referenced by the command line tool (i.e. snapcraft). |
parts. <part-name>. plugin |
The plugin to drive the build process. Type: string Every part drives its build through a plugin, this entry declares the plugin that will drive the build process for <part-name>. Refer to snapcraft plugins for more information on the available plugins and the specific attributes they add to the parts.<part-name>. namespace. |
parts. <part-name>. source |
A URL or path to a source tree to build. Type: string This can be a local path or remote, and can refer to a directory tree, a compressed archive or a revision control repository. This entry supports additional syntax, for more information refer to Advanced grammar. |
parts. <part-name>. source-type |
Used when the type-of source entry cannot be detected.Type: enum Can be one of the following: [bzr|deb|git|hg|local|mercurial|rpm|subversion|svn|tar|zip|7z]
|
parts. <part-name>. source-checksum |
Used when source represents a file. Type: string Takes the syntax <algorithm>/<digest>, where <algorithm> can be any of: md5, sha1, sha224, sha256, sha384, sha512, sha3_256, sha3_384 or sha3_512. When set, the source is cached for multiple uses in different snapcraft projects. |
parts. <part-name>. source-depth |
Depth of history for sources using version control. Type: integer Source repositories under version control are cloned or checked out with full history. Specifying a depth will truncate the history to the specified number of commits. |
parts. <part-name>. source-branch |
Work on a specific branch for source repositories under version control. Type: string
|
parts. <part-name>. source-commit |
Work on a specific commit for source repositories under version control. Type: string
|
parts. <part-name>. source-tag |
Work on a specific tag for source repositories under version control. Type: string
|
parts. <part-name>. source-subdir |
A path within the source to set as the working directory when building. Type: string
|
parts. <part-name>. after |
Ensures that all the <part-name>s listed in after are staged before this part begins its lifecycle. Type: list[string]
|
parts. <part-name>. build-environment
|
Type: list[string]A list of environment variable assignments that is applied during the build step, it is exported in order which allows for later values to override (or modify) earlier values. |
parts. <part-name>. build-snaps |
A list of snap names to install that are necessary to build <part-name>. Type: list[string] If a specific channel is required, the syntax is of the form <snap-name>/<channel>. This entry supports additional syntax, for more information refer to Advanced grammar
|
parts. <part-name>. build-packages |
A list of packages required to build a snap. Type: list[string] Packages are installed using the host’s package manager, such as apt or dnf, and are required for <part-name> to build correctly. This entry supports additional syntax, for more information refer to Advanced grammar. Example: [ libssl-dev, libssh-dev, libncursesw5-dev]
|
parts. <part-name>. stage-packages |
A list of packages required at runtime by a snap. Type: list[string] Packages are installed using the host’s package manager, such as apt or dnf, and are required by <part-name> to run. This entry supports additional syntax, for more information refer to Advanced grammar. Example: [python-zope.interface, python-bcrypt]
|
parts. <part-name>. stage-snaps |
A list of snaps required at runtime by a snap. Type: list[string] Snaps are required by <part-name> to run. They are fetched using snap download, and are unpacked into the snap being built. This entry supports additional syntax, for more information refer to Advanced grammar. Example: [hello, black/latest/edge]
|
parts. <part-name>. organize |
A map of files to rename. Type: dict In the key/value pair, the key represents the path of a file inside the part and the value represents how the file is going to be staged. Example: bin/snapcraftctl: bin/scriptlet-bin/snapcraftctl. |
parts. <part-name>. filesets |
A key to represent a group of files, or a single file. See Snapcraft filesets for further details. |
parts. <part-name>. stage |
A list of files from <part-name> to stage. Type: list[string] Rules applying to the list here are the same as those of filesets. Referencing of fileset keys is done with a $ prefixing the fileset key, which will expand with the value of such key. |
parts. <part-name>. parse-info |
Defines the content to adopt when using external metadata. Type: string It is a relative path to a supported metadata file from the part source, build or install directory (SNAPCRAFT_PART_SRC, SNAPCRAFT_PART_BUILD, SNAPCRAFT_PART_INSTALL). See Using external metadata for more details. |
parts. <part-name>. prime |
A list of files from <part-name> to prime. Type: list[string] Rules applying to the list here are the same as those of filesets. Referencing of fileset keys is done with a $ prefixing the fileset key, which will expand with the value of such key. |
parts. <part-name>. prepare deprecated |
The release of Snapcraft 3.0 made this key obsolete. Use override-build instead. Runs a script before the plugin’s build step. Type: multiline string The script is run before the build step defined for parts.<part-name>.plugin starts. The working directory is the base build directory for the given part. The defined script is run with /bin/sh and set -e. A set of Environment Variables will be available to the script. |
parts. <part-name>. override-build |
Replaces a plugin’s default build process with a script. Type: multiline string The shell script defined here replaces the build step of the plugin, defined in parts.<part-name>.plugin. The working directory is the base build directory for the given part. The defined script is run with /bin/sh and set -e. A set of Environment Variables will be available to the script. |
parts. <part-name>. override-prime |
Replaces a plugin’s default prime process with a script. Type: multiline string The shell script defined here replaces the prime step of the plugin, defined in parts.<part-name>.plugin. The working directory is the base prime directory for the given part. The defined script is run with /bin/sh and set -e. A set of Environment Variables will be available to the script. |
parts. <part-name>. override-pull |
Replaces a plugin’s default pull process with a script. Type: multiline string The shell script defined here replaces the pull step of the plugin, defined in parts.<part-name>.plugin. The working directory is the base pull directory for the given part. The defined script is run with /bin/sh and set -e. A set of Environment Variables will be available to the script. |
parts. <part-name>. override-stage |
Replaces a plugin’s default stage process with a script. Type: multiline string The shell script defined here replaces the stage step of the plugin, defined in parts.<part-name>.plugin. The working directory is the base stage directory for the given part. The defined script is run with /bin/sh and set -e. A set of Environment Variables will be available to the script. |
parts. <part-name>. install deprecated |
The release of Snapcraft 3.0 made this key obsolete. Use override-build instead. Runs a script after the plugin’s build step. Type: multiline string The shell script defined here is run after the build step of the plugin defined in parts.<part-name>.plugin starts. The working directory is the base build directory for the given part. The defined script is run with /bin/sh and set -e. A set of Environment Variables will be available to the script. |
parts. <part-name>. build-attributes
|
A list of named attributes to modify the behaviour of plugins. Type: enum For more information, refer to Snapcraft parts metadata. |
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