Configuration

Introduction

You can configure the application manager through configuration (config) files and the command line. To display the currently supported command line options, run appman --help. Some of these options can also be set via config files that are referenced on the command line with the --config-file <filename> option.

The config file is a YAML file that follows the same rules as all the other YAML files used in the application manager.

Variable Substitution

Before parsing the YAML document, the application manager substitutes variables denoted by a syntax similar to bash: ${VariableName}. There are different types of variables that can be substituted this way:

Multiple Values

If an option is specified in more than one place: either on the command line and the config files, or across multiple config files, the final value is resolved based on these rules:

• Options are parsed from all the config files available, in the order in which they appear on the command line. Values are overridden by config files, as they are loaded.
• Options that are specified directly via the command line always override values in any config file.

Time Duration Values

Starting with version 6.8, all time duration values should be specified with a unit suffix. The following units are supported: h, min, s, ms and us. Fields that have existed before 6.8 still accept values without a unit suffix, but it is recommended to upgrade all time durations to use the new syntax. In addition, a zero time duration can also be specified as off.

Example

A very minimalistic am-config.yaml example would be something like this, which defines the main qml entry point and two import paths:

Main Configuration

formatVersion: 1
formatType: am-configuration
---
ui:
  mainQml: "${CONFIG_DIR}/main.qml"
  importPaths: [ "${CONFIG_DIR}/imports/shared", "${CONFIG_DIR}/imports/sysui" ]

D-Bus Specification

These YAML objects describe both, which D-Bus interfaces are registered on, as well as access policies.

The code snippet below shows a simple example, that only allows applications with the appstore capability, running with user ID 1000 to call the installer's startPackageInstallation function, while preventing anyone to remotely call acknowledgePackageInstallation:

...
dbus:
  io.qt.PackageManager:
    register: 'session'
    policy:
      startPackageInstallation:
        uids: [ 1000 ]
        capabilities: [ 'appstore' ]
      acknowledgePackageInstallation: null
...

Only the public D-Bus interfaces of the application manager can be configured this way. The names of these available interfaces are as follows:

Runtime Configuration

The runtime configuration sub-objects are specific to the actual runtimes, so the table below has an additional column specifying which runtime a configuration option applies to:

Crash Action Specification

These sub-objects specify which actions to take, if the application manager or QML runtimes are crashing.

The following conditions are handled:

• Uncaught exceptions. Exceptions derived from std::exception also show details on what() occurred.
• SIGSEGV
• SIGABRT
• SIGBUS
• SIGILL
• SIGFPE
• SIGPIPE
• SIGQUIT
• SIGSYS

Intent Timeout Specification

The intents/timeouts sub-object lets you specify the exact timeouts with milli-seconds precision for the asynchronous IPC used to implement the intents mechanism. Any intent whose lifetime exceeds a timeout for the stages shown below is canceled by the system and an error reply is sent back to the original sender. Setting any of the timeout values to 0 or a negative number disables the timeout handling for that specific stage.

Please be aware that due to the asynchronous nature of the intent delivery, an intent might be canceled by the system because it ran into either a replyFromApplication or replyFromSystem timeout, although the receiver still received and processed it.

OpenGL Specification

The opengl sub-object lets you specify the required OpenGL version and/or profile.