Application Policies
An application's permissions and settings are stored in the app_policies property in a Policy Table. The application policies are used to grant applications access to a specific set of features, such as vehicle data and/or running in the background. Any other application related data, such as user-consents, can also be stored in application policies as well.
Application ID
Settings for a specific application are stored in the app_policies object as a property named after the application's unique ID (e.g. "663645645" or any string of at most 100 characters). The value of this property can be either an object containing properties listed below or a reference to another sibling property (e.g. "default" or "device"). In addition, a special value of "null" can be used to indicate that the application has been revoked.
| Application Property | Type | Description |
|---|---|---|
| keep_context | Boolean | When true, allows the application to display messages even if another app enters the foreground (HMI level FULL). |
| steal_focus | Boolean | When true, allows the application to steal the foreground from another application at will. |
| priority | String | Priority level assigned to the application. |
| default_hmi | String | HMI level given to the application following a successful registration with SDL Core. |
| groups | Array of Strings | A list of functional groupings the application has access to. |
| preconsented_groups | Array of Strings | List of functional groupings that do not require a user consent because the consent has already been given in another place. (e.g. an application EULA) |
| RequestType | Array of Strings | List of Request Types that an app is allowed to use in a SystemRequest RPC. If omitted, all requestTypes are disallowed. If an empty array is provided, all requestTypes are allowed. |
| RequestSubType | Array of Strings | List of Request SubTypes (defined by individual OEMs) that an app is allowed to use in a SystemRequest RPC. If omitted, all requestSubTypes are disallowed. If an empty array is provided, all requestSubTypes are allowed. |
| AppHMIType | Array of Strings | List of HMI Types used to group the application into different containers in an HMI system. If omitted, all appHMITypes are allowed. |
| heart_beat_timeout_ms | String | A streaming/projection app will be automatically disconnected if no app communication occurs over this period of time (in milliseconds). |
| certificate | String | The app's encryption certificate for video streaming/projection (if applicable) |
| nicknames | Array of Strings | A list of names the application goes by. Some OEMs may require the app's name to match a value in this array in order to run. |
Application HMI Types
An application can be categorized by an HMI type allowing the SDL-enabled head unit to understand how to appropriately handle the application. There are several HMI types listed below.
| Application HMI Type | Description |
|---|---|
| BACKGROUND_PROCESS | |
| COMMUNICATION | |
| DEFAULT | |
| INFORMATION | |
| MEDIA | |
| MESSAGING | |
| NAVIGATION | |
| SOCIAL | |
| SYSTEM | |
| TESTING | |
| WEB_VIEW |
Application HMI Levels
An HMI Level describes the state of an application. Resources are granted to an application based on its current state. While some resources are granted automatically to an application in a specific HMI Level, many can be controlled by the Policy Table.
| Level | Value | Short Description |
|---|---|---|
| Full | 0 | An application is typically in Full when it is displayed in the HMI. In Full an application has access to the HMI supported resources, e.g. UI, VR, TTS, audio system, and etc. |
| Limited | 1 | An application is typically placed in Limited when a message or menu is displayed Limited to restrict its permissions. |
| Background | 2 | An application is typically in Background when it is not being displayed by the HMI. When in Background an application can send RPCs according to the Policy Table rules. |
| None | 3 | When placed in None an application has no access to HMI supported resources. |
Request Types
| Request Type | Description |
|---|---|
| HTTP | |
| FILE_RESUME | |
| AUTH_REQUEST | |
| AUTH_CHALLENGE | |
| AUTH_ACK | |
| PROPRIETARY | |
| QUERY_APPS | |
| LAUNCH_APP | |
| LOCK_SCREEN_ICON_URL | |
| TRAFFIC_MESSAGE_CHANNEL | |
| DRIVER_PROFILE | |
| VOICE_SEARCH | |
| NAVIGATION | |
| PHONE | |
| CLIMATE | |
| SETTINGS | |
| VEHICLE_DIAGNOSTICS | |
| EMERGENCY | |
| MEDIA | |
| FOTA | |
| OEM_SPECIFIC | Used for OEM defined requests, requestSubType should be used to determine how to handle this type of request. |
Default
A default application configuration can be stored in the app_policies object as a property named default. This property's value is an object containing any valid application property excluding certificate and nicknames.
Device
Permissions granted to the user's device post-DataConsent.
Example
An example of how the Application Policy portion of a Policy Table might look.
"app_policies": { "default": { "keep_context": true, "steal_focus": true, "priority": "NONE", "default_hmi": "NONE", "groups": [ "Base-1" ], "preconsented_groups": [], "RequestType": [], "memory_kb": 5, "watchdog_timer_ms": 55 }, "device": { "keep_context": true, "steal_focus": true, "priority": "NONE", "default_hmi": "NONE", "groups": [ "Base-2" ], "preconsented_groups": [] }, "pre_DataConsent": { "keep_context": true, "steal_focus": true, "priority": "NONE", "default_hmi": "NONE", "groups": [ "BaseBeforeDataConsent" ], "preconsented_groups": [], "memory_kb": 5, "watchdog_timer_ms": 55 }, "[App ID 1]": "null", "[App ID 2]": "default", "[App ID 3]": { "nicknames": [ "Awesome Music App" ], "keep_context": true, "steal_focus": true, "priority": "NONE", "default_hmi": "NONE", "groups": [ "Base-1", "VehicleInfo-1" ], "preconsented_groups": [], "RequestType": [], "RequestSubType": [ "Sub Type" ], "AppHMIType": [ "MEDIA" ], "memory_kb": 5, "watchdog_timer_ms": 55, "certificate": "[Your Certificate]" } }