ORG.FREEDESKTOP.SYSUPDATE1(5)

NAME
org.freedesktop.sysupdate1 - The D-Bus interface of systemd-sysupdated

INTRODUCTION

systemd-sysupdated.service(8) is a system service that allows unprivileged clients to update the system. This page describes the D-Bus interface.

WARNING! This API is currently unstable and is thus subject to breaking changes between versions of systemd.

THE MANAGER OBJECT

The service exposes the following interfaces on the Manager object on the bus:

    node /org/freedesktop/sysupdate1 {
      interface org.freedesktop.sysupdate1.Manager {
        methods:
          ListTargets(out a(sso) targets);
          ListJobs(out a(tsuo) jobs);
          ListAppStream(out as urls);
        signals:
          JobRemoved(t id,
                     o path,
                     i status);
      };
      interface org.freedesktop.DBus.Peer { ... };
      interface org.freedesktop.DBus.Introspectable { ... };
      interface org.freedesktop.DBus.Properties { ... };
    };

  Methods

ListTargets() returns a list all known update targets. It returns an array of structures which consist of a string indicating the target's class (see Target's Class property below for an explanation of the possible values), a string with the name of the target, and the target object path.

ListJobs() returns a list all ongoing jobs. It returns an array of structures which consist of a numeric job ID, a string indicating the job type (see Job's Type property below for an explanation of the possible values), the job's progress, and the job's object path.

ListAppStream() returns an array of all the appstream catalog URLs that this service knows about. See Target's GetAppStream() method below for more details.

  Signals

The JobRemoved() signal is sent each time a job finishes, is canceled or fails. It also carries the job ID and object path, followed by a numeric status code. If the status is zero, the job has succeed. A positive status should be treated as an exit code (i.e. "EXIT_FAILURE"), and a negative status should be treated as a negative errno-style error code (i.e. "-EINVAL").

THE TARGET OBJECT

A target is a component of the system (i.e. the host itself, a sysext, a confext, etc.) that can be updated by systemd-sysupdate(8).

The service exposes the following interfaces on Target objects on the bus:

    node /org/freedesktop/sysupdate1/target/host {
      interface org.freedesktop.sysupdate1.Target {
        methods:
          List(in  t flags,
               out as versions);
          Describe(in  s version,
                   in  t flags,
                   out s json);
          CheckNew(out s new_version);
          Acquire(in  s new_version,
                  in  t flags,
                  out s new_version,
                  out t job_id,
                  out o job_path);
          Install(in  s new_version,
                  in  t flags,
                  out s new_version,
                  out t job_id,
                  out o job_path);
          Vacuum(out u instances,
                 out u disabled_transfers);
          GetAppStream(out as appstream);
          GetVersion(out s version);
          ListFeatures(in  t flags,
                       out as features);
          DescribeFeature(in  s feature,
                          in  t flags,
                          out s json);
          SetFeatureEnabled(in  s feature,
                            in  i enabled,
                            in  t flags);
        properties:
          @org.freedesktop.DBus.Property.EmitsChangedSignal("const")
          readonly s Class = '...';
          @org.freedesktop.DBus.Property.EmitsChangedSignal("const")
          readonly s Name = '...';
          @org.freedesktop.DBus.Property.EmitsChangedSignal("const")
          readonly s Path = '...';
      };
      interface org.freedesktop.DBus.Peer { ... };
      interface org.freedesktop.DBus.Introspectable { ... };
      interface org.freedesktop.DBus.Properties { ... };
    };

  Methods

List() returns a list of versions available for this target. Additional options may be passed through the flags argument. Valid flags are defined as follows:

    #define SD_SYSUPDATE_OFFLINE    (UINT64_C(1) << 0)

When SD_SYSUPDATE_OFFLINE is set, this method returns only the versions installed locally. Otherwise, this method pulls metadata from the network and returns all versions available for this target. Use Describe() to query more information about each version returned by this method.

Describe() returns all known information about a given version as a JSON object. The version argument is used to pass the version to be described. Additional options may be passed through the flags argument. This method supports the same flags as List(). The returned JSON object contains several known keys. More keys may be added in the future. The currently known keys are as follows:

"version"
    A string containing the version number.

"newest"
    A boolean indicating whether this version is the latest available for the target.

"available"
    A boolean indicating whether this version is available for download.

"installed"
    A boolean indicating whether this version is installed locally.

"obsolete"
    A boolean indicating whether this version is considered obsolete by the service, and is therefore disallowed from being installed.

"protected"
    A boolean indicating whether this version is exempt from deletion by a Vacuum() operation.

"incomplete"
    A boolean indicating whether this version is incomplete, which means that it is missing some file. Note that only installed incomplete versions will be offered by the service; versions that are incomplete on the server-side are completely ignored. Incomplete versions can be repaired in-place by calling Acquire() and Install() on that version.

"changelogUrls"
    A list of strings that contain user-presentable URLs to change logs associated with this version.

CheckNew() checks if a newer version is available for this target. This method pulls metadata from the network. If a newer version is found, this method returns the version number. If no newer version is found, this method returns an empty string. Use Describe() to query more information about the version returned by this method.

Acquire() downloads an update for this target, if one is available. If a new_version is specified, that is the version that gets downloaded. Otherwise, the latest version is downloaded. Call Install() to install the acquired update. The flags argument is added for future extensibility. No flags are currently defined, and the argument is required to be set to "0". This method pulls both metadata and payload data from the network.

Install() installs an already-acquired update for this target. If a new_version is specified, that is the version that gets installed, assuming it has already been acquired. Otherwise, the latest acquired version is installed. The flags argument is added for future extensibility. No flags are currently defined, and the argument is required to be set to "0".

Unlike all the other methods in this interface, Acquire() and Install() do not wait for their jobs to complete. Instead, they return the job's numeric ID and object path as soon as the job begins, so that the caller can listen for progress updates or cancel the operation. These methods also return the version the target will be updated to, for cases where no version was specified by the caller. Listen for the Manager's JobRemoved() signal to detect when the job is complete.

Vacuum() deletes old installed versions of this target to free up space. It returns the number of instances that have been deleted.

GetAppStream() returns a list of HTTP/HTTPS URLs to this target's appstream catalog[1] XML files. If this target has no appstream catalogs, the method will return an empty list. These catalog files can be used by software centers (such as GNOME Software or KDE Discover) to present rich metadata about the target, including a display name, changelog, icon, and more. The returned catalogs will include special metadata[2] to allow the software center to correctly associate the catalogs with this target.

GetVersion() returns the current version of this target, if any. The current version is the newest version that is installed. Note that this is not necessarily the same thing as the booted or currently-in-use version of the target. For example, on the host system the booted version is the current version most of the time, but if an update is installed and pending a reboot it will become the current version instead. You can query the booted version of the host system via IMAGE_VERSION in /etc/os-release. If the target has no current version, the function will return an empty string.

ListFeatures() returns a list of this target's optional features, by ID. The flags argument is added for future extensibility, and must be set to 0. If the target has no optional features, the method returns an empty array.

DescribeFeature() returns all known information about a given optional feature. The feature argument is used to pass the ID of the feature to be described. The flags argument is added for future extensibility, and must be set to 0. The returned JSON object contains several known keys. More keys may be added in the future. The currently known keys are as follows:

"name"
    A string containing the feature's name.

"description"
    An optional string that contains a user-presentable description that identifies this feature

"enabled"
    A boolean indicating whether this feature is enabled.

"documentationUrl"
    An optional string that contains a user-presentable HTTP/HTTPS URL to documentation about this feature.

"appstreamUrl"
    An optional string that contains an HTTP/HTTPS URL to an appstream catalog[1] XML file containing metadata about this feature.

"transfers"
    An optional array of strings that list which transfer definitions belong to this feature.

SetFeatureEnabled() writes an appropriate drop-in file to enable or disable the specified optional feature. If enable is zero, the feature is disabled. When greater than zero, the feature is enabled. When less than zero, the feature is reset to the distribution's default. The flags argument is added for future extensibility, and must be set to 0. The feature does not have to exist; this allows for graceful handling of masked features, and for preemptive decisions to be made about features that are planned to appear in future releases of the OS. The drop-in will have a filename of "50-systemd-sysupdate-enabled.conf". This method only changes configuration files; to actually apply the changes, clients will need to call Acquire() and Install(). Depending on the exact needs of the client, it can choose to update the system to the latest available version, or it can extend the newest existing installation in-place (by passing in the version returned by GetVersion()). For now, this method only works with the "host" target.

  Properties

The Class property exposes the class of this target, which describes where it was enumerated. Possible values include: "machine" for containers and virtual machines managed by systemd-machined.service(8), "portable" for portable services[3], "sysext" for system extensions managed by systemd-sysext(8), "confext" for configuration extensions managed by systemd-confext(8), "component" for components accepted by the --component= option of systemd-sysupdate(8), and "host" for the host system itself. At most one target will have a class of "host".

The Path property exposes more detail about where this target was found. For "machine", "portable", "extension", and "confext" targets, this is the file path to the image. For "component" and "host" targets, this is the name of a sysupdate.d(5) directory.

The Name property exposes the name of this target. Note that the name is unique within a class but is not necessarily unique between classes. For instance, it is possible to have both a "portable" target named "foobar" and an "extension" target named "foobar", but it is not possible to have two "portable" targets named "foobar".

  Security

Method calls on this service are authenticated via polkit[4].

List(), Describe(), and CheckNew() use the polkit action org.freedesktop.sysupdate1.check. By default, this action is permitted without administrator authentication. Cancellation of these methods uses the polkit action org.freedesktop.sysupdate1.cancel-check. By default, this cancellation action is permitted without administrator authentication.

Acquire() and Install() use the polkit action org.freedesktop.sysupdate1.update when no version is specified. By default, this action is permitted without administrator authentication. When a version is specified, org.freedesktop.sysupdate1.update-to-version is used instead. By default, this alternate action requires administrator authentication. Cancellation of these methods uses the polkit actions org.freedesktop.sysupdate1.cancel-update and org.freedesktop.sysupdate1.cancel-update-to-version. By default, these cancellation actions are permitted without administrator authentication.

Vacuum() uses the polkit action org.freedesktop.sysupdate1.vacuum. By default, this action requires administrator authentication. Cancellation of this method uses the polkit action org.freedesktop.sysupdate1.cancel-vacuum. By default, this cancellation action is permitted without administrator authentication.

SetFeatureEnabled() uses the polkit action org.freedesktop.sysupdate1.manage-features. By default, this action requires administrator authentication. Cancellation is not supported for this method.

GetAppStream(), GetVersion(), ListFeatures(), and DescribeFeature() are unauthenticated and may be called by anybody. Cancellation is not supported for these methods, or is always allowed without administrator authentication.

All methods called on this interface expose additional variables to the polkit rules. "class" contains the class of the Target being acted upon, and "name" contains the name of the same Target. Additionally, each method exposes its arguments to the rule. Flags are mapped as follows:

    • SD_SYSUPDATE_OFFLINE → "update"

THE JOB OBJECT

A job is an ongoing operation, started by one of the methods on a Target object.

The service exposes the following interfaces on Job objects on the bus:

    node /org/freedesktop/sysupdate1/job/_1 {
      interface org.freedesktop.sysupdate1.Job {
        methods:
          Cancel();
        properties:
          @org.freedesktop.DBus.Property.EmitsChangedSignal("const")
          readonly t Id = ...;
          @org.freedesktop.DBus.Property.EmitsChangedSignal("const")
          readonly s Type = '...';
          @org.freedesktop.DBus.Property.EmitsChangedSignal("const")
          readonly b Offline = ...;
          readonly u Progress = ...;
      };
      interface org.freedesktop.DBus.Peer { ... };
      interface org.freedesktop.DBus.Introspectable { ... };
      interface org.freedesktop.DBus.Properties { ... };
    };

  Methods

The Cancel() method may be used to cancel the job. It takes no parameters.

  Properties

The Id property exposes the numeric job ID of the job object.

The Type property exposes the type of operation (one of: "list", "describe", "check-new", "acquire", "install", "vacuum", or "describe-feature").

The Offline property exposes whether the job is permitted to access the network or not.

The Progress property exposes the current progress of the job as a value between 0 and 100. It is only available for "acquire" and "install" jobs; for all other jobs it is always 0.

  Security

Cancel() uses the polkit action that corresponds to the method that started this job. For instance, trying to cancel a "list" job will require polkit to permit the org.freedesktop.sysupdate1.check action.

EXAMPLES

Example 1. Introspect org.freedesktop.sysupdate1.Manager on the bus

    $ gdbus introspect --system \
      --dest org.freedesktop.sysupdate1 \
      --object-path /org/freedesktop/sysupdate1

Example 2. Introspect org.freedesktop.sysupdate1.Target on the bus

    $ gdbus introspect --system \
      --dest org.freedesktop.sysupdate1 \
      --object-path /org/freedesktop/sysupdate1/target/host

Example 3. Introspect org.freedesktop.sysupdate1.Job on the bus

    $ gdbus introspect --system \
      --dest org.freedesktop.sysupdate1 \
      --object-path /org/freedesktop/sysupdate1/job/_1

VERSIONING

These D-Bus interfaces follow the usual interface versioning guidelines[5].

HISTORY

  The Manager Object

ListTargets(), ListJobs(), ListAppStream(), and JobRemoved() were added in version 257.

  The Target Object

List(), Describe(), CheckNew(), Acquire(), Install(), Vacuum(), GetAppStream(), GetVersion(), ListFeatures(), DescribeFeature(), SetFeatureEnabled(), Class, Name, and Path were added in version 257.

  The Job Object

Cancel(), Id, Type, Offline, and Progress were added in version 257.

SEE ALSO

systemd(1), systemd-sysupdated.service(8), updatectl(1)

NOTES

1.  appstream catalog
    https://wwww.freedesktop.org/software/appstream/docs/chap-CatalogData.html

2.  special metadata
    https://systemd.io/APPSTREAM_BUNDLE

3.  portable services
    https://systemd.io/PORTABLE_SERVICES

4.  polkit
    https://www.freedesktop.org/software/polkit/docs/latest/

5.  the usual interface versioning guidelines
    https://0pointer.de/blog/projects/versioning-dbus.html