The app keys and values in snapcraft.yaml detail the applications and services that a snap wants to expose, including how they’re executed and which resources they can access.
See Snapcraft top-level metadata and Snapcraft parts metadata for details on how apps and parts are configured within snapcraft.yaml.
Type: dict
A map of app-names
representing entry points to run for the snap.
Type: dict
The name exposed to run a program inside the snap.
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>
.
The following are keys that can be within apps. (for example, apps.<app-name>.daemon
):
Type: enum
Can be one of the following:
none
(Disables the creation of an env variable wrapper.)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.
Type: Array of string
A list of applications to be started after <app-name>
. Applications must be part of the same snap. The order of the applications in the list has no effect on their launch order.
Requires daemon
to be set in the app metadata. See Services and daemons for details.
See also before.
Type: string
Defines the name of the .desktop
file used to start an application with the desktop session.
The desktop file is placed in $SNAP_USER_DATA/.config/autostart
, and the application is started using the app’s command wrapper (<name>.<app>
) plus any argument present in the Exec=
line within the .desktop file.
Example: autostart: my-chat.desktop
See Autostart desktop files for an example of both the desktop file and the Exec file entry.
Type: Array of string
An ordered list of applications to be started before <app-name>
. Applications must be part of the same snap.
Requires daemon
to be set in the app metadata. See Services and daemons for details.
See also after.
Type: string
The command to run inside the snap when <app-name>
is invoked.
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
.
Type: Array of string
A list of command to be executed, in order, before the command referenced by apps.<app-name>.command
.
See Proposal: support command-chain in apps and hooks for further details.
To ensure that the Snapd distribution user running supports this feature, add the command-chain
value to the assumes
property.
Type: string
An identifier to a desktop-id within an external appstream file.
See Using external metadata for more details.
Type: enum
Declares that <app-name>
is a system daemon.
Can be one of the following:
simple
: the command is the main process.oneshot
: the configured command will exit after completionforking
: the configured command calls fork()
as part of its start-up. The parent process is then expected to exit when start-up is completenotify
: the command configured will send a signal to systemd to indicate that it’s running.Type: string
Location of the .desktop file.
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
share/applications/my-app.desktop
See Desktop files for menu integration for the complete details about desktop shortcuts and entries for snaps on Linux.
Type: dict
A set of key-value pairs specifying the contents of environment variables.
Key is the environment variable name; Value is the contents of the environment variable.
Example: LANG: C.UTF-8
Type: list[string] | string
(optional)
Snapcraft extensions enable snap developers to easily incorporate a set of common requirements into a snap, such as those to integrate an application with a desktop environment.
For further details, see Snapcraft extensions, and see Supported extensions for a full list of supported extensions.
Example: [gnome-3-38]
Type: string
Defines whether a freshly installed daemon is started automatically, or whether startup control is deferred to the snap.
If a snap was installed prior to the daemon component being added, install-mode will determine whether or not the daemon is started automatically when the component is delivered via a snap update.
When disabled, the snap needs to use snapctl with a hook, or another management agent, to start the daemon.
Can be either of the following:
enable
: the daemon is started after being installed.disable
: the daemon will not be started after installation.Defaults to enable
.
Requires daemon
to be set in the app metadata. See Services and daemons for details.
Type: string
The socket abstract name or socket path.
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>
Example:
unix:
listen-stream: $SNAP_COMMON/lxd/unix.socket
socket-mode: 0660
Type: type[object]
<app-name>
attributes to pass through to snap.yaml
without snapcraft validation.
See Using in-development features for further details.
Type: list[string]
Plugs for interfaces to connect to.
<app-name>
will make these plug connections when running in strict
confinement
For interfaces that need attributes, see top-level plugs.
Example: [home, removable-media, raw-usb
]
Type: string
Runs a command from inside the snap after a service stops.
Requires daemon
to be set in the app metadata. See Services and daemons for details.
Type: string
Controls how the daemon or app should be treated during a snap refresh.
Can be either of the following:
endure
: the daemon will not be restarted during a snap refresh.restart
: the daemon will be restarted during a snap refresh.ignore-running
: the app will not block a snap refresh (can only be set for apps).Defaults to restart
.
Requires daemon
to be set in the app metadata. See Services and daemons for details.
Type: enum
Condition to restart the daemon under.
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 in the app metadata. See Services and daemons for details.
Type: list[string]
Slots for interfaces to connect to.
<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
]
Type: dict
Maps a daemon’s sockets to services and activates them.
Requires an activated daemon socket.
Requires apps.<app-name>.plugs
to declare the network-bind
plug.
Type: integer
The mode of a socket in octal.
Type: string
The path to a command inside the snap to run to stop the service.
Requires daemon
to be set in the app metadata. See Services and daemons for details.
Type: string
The length of time to wait before terminating a service.
Time duration units can be 10ns
, 10us
, 10ms
, 10s
, 10m
. Termination is via SIGTERM
(and SIGKILL
if that doesn’t work).
Type: timer-string
Schedules when, or how often, to run a service or command.
See Timer string format for further details on the required syntax.
Requires daemon
to be set in the app metadata. See Services and daemons for details.
Last updated 2 days ago.