Applying for Permissions

When to Use

Application permissions are used to prevent unauthorized access to sensitive data or critical functions. The Ability Privilege Level (APL) of an application can be normal (default), system_basic, or system_core. The permission types include system_grant and user_grant. For details about the permissions for applications, see the Application Permission List.

This document describes the following operations:

Declaring Permissions in the Configuration File
Declaring the ACL
Requesting User Authorization
Pre-authorizing user_grant Permissions

Declaring Permissions in the Configuration File

The permissions required by an application must be declared one by one in the configuration file of the project. Otherwise, the application cannot obtain the permissions.

NOTE

If an application of the normal APL requires a permission of the system_basic or system_core level, you must also declare the permission in the ACL.

The following table describes the fields in the configuration file.

Field	Mandatory	Description
name	Yes	Name of the permission.
reason	No	Reason for requesting the permission. This parameter is mandatory when a user_grant permission is required.
usedScene	No	Application scenario of the permission. This parameter is mandatory when a user_grant permission is required.
abilities	No	Abilities that require the permission. The value is an array. Applicable model: stage
ability	No	Abilities that require the permission. The value is an array. Applicable model: FA
when	No	Time when the permission is required. Value: - inuse: The permission is required only when the application is in use. - always: The permission is required no matter whether the application is in use.

Stage Model

If your application is developed based on the stage model, declare the required permissions in module.json5.

{
  "module" : {
    // ...
    "requestPermissions":[
      {
        "name" : "ohos.permission.PERMISSION1",
        "reason": "$string:reason",
        "usedScene": {
          "abilities": [
            "FormAbility"
          ],
          "when":"inuse"
        }
      },
      {
        "name" : "ohos.permission.PERMISSION2",
        "reason": "$string:reason",
        "usedScene": {
          "abilities": [
            "FormAbility"
          ],
          "when":"always"
        }
      }
    ]
  }
}

FA Model

If your application is developed based on the FA model, declare the required permissions in config.json.

{
  "module" : {
    // ...
    "reqPermissions":[
      {
        "name" : "ohos.permission.PERMISSION1",
        "reason": "$string:reason",
        "usedScene": {
          "ability": [
            "FormAbility"
          ],
          "when":"inuse"
        }
      },
      {
        "name" : "ohos.permission.PERMISSION2",
        "reason": "$string:reason",
        "usedScene": {
          "ability": [
            "FormAbility"
          ],
          "when":"always"
        }
      }
    ]
  }
}

Declaring the ACL

If an application of the normal APL requires permissions of the system_basic or system_core level, you must also declare the required permissions in the ACL.

For example, if an application needs to access audio clips of a user and capture screenshots, it requires the ohos.permission.WRITE_AUDIO permission (of the system_basic level) and the ohos.permission.CAPTURE_SCREEN permission (of the system_core level). In this case, you need to add the required permissions to the acls field in the HarmonyAppProvision configuration file.

{
	// ...
	"acls":{
		"allowed-acls":[
			"ohos.permission.WRITE_AUDIO",
      "ohos.permission.CAPTURE_SCREEN"
		]
	}
}

Requesting User Authorization

User authorization is required when an application needs to access user privacy information (such as Location or Calendar information) or using system abilities (such as the camera ability to take photos or record videos). In this case, the application requires a user_grant permission. Before the application accesses the data or using the system ability, a verification is performed to check whether the user has granted the permission to the application. If the user has not granted the permission, a dialog box will be displayed to request user authorization. The following figure shows an example.

Figure 1 Requesting user authorization

NOTE

Each time before an API protected by a user_grant permission is called, requestPermissionsFromUser() will be called to request user authorization. After the permission is granted, the user may revoke the authorization in Settings. Therefore, the previous authorization status cannot be persistent.

Stage Model

Example: Apply for the permission for an application to access the Calendar.

Declare the ohos.permission.READ_CALENDAR permission in the configuration file. For details, see Declaring Permissions in the Configuration File.

Check whether the user has granted the permission.

Use checkAccessToken() to check whether the user has granted the permission. If yes, the application can access the Calendar. Otherwise, user authorization is required.

import bundleManager from '@ohos.bundle.bundleManager';
import abilityAccessCtrl, { Permissions } from '@ohos.abilityAccessCtrl';

async function checkAccessToken(permission: Permissions): Promise<abilityAccessCtrl.GrantStatus> {
  let atManager = abilityAccessCtrl.createAtManager();
  let grantStatus: abilityAccessCtrl.GrantStatus;

  // Obtain the access token ID of the application.
  let tokenId: number;
  try {
    let bundleInfo: bundleManager.BundleInfo = await bundleManager.getBundleInfoForSelf(bundleManager.BundleFlag.GET_BUNDLE_INFO_WITH_APPLICATION);
    let appInfo: bundleManager.ApplicationInfo = bundleInfo.appInfo;
    tokenId = appInfo.accessTokenId;
  } catch (err) {
    console.error(`Failed to get bundle info for self. Code is ${err.code}, message is ${err.message}`);
  }

  // Check whether the user has granted the permission.
  try {
    grantStatus = await atManager.checkAccessToken(tokenId, permission);
  } catch (err) {
    console.error(`Failed to check access token. Code is ${err.code}, message is ${err.message}`);
  }

  return grantStatus;
}

async function checkPermissions(): Promise<void> {
  const permissions: Array<Permissions> = ['ohos.permission.READ_CALENDAR'];
  let grantStatus: abilityAccessCtrl.GrantStatus = await checkAccessToken(permissions[0]);

  if (grantStatus === abilityAccessCtrl.GrantStatus.PERMISSION_GRANTED) {
    // If the user has granted the permission, the application can access the Calendar.
  } else {
    // Apply for the permission to access the Calendar.
  }
}

Request user authorization dynamically.

Use requestPermissionsFromUser() to apply for permissions from the user when the application is running. A list of permissions, such as the permissions to access the Location, Calendar, camera, and microphone, can be passed in. The user can grant or deny the permissions.

You can have requestPermissionsFromUser() called in onWindowStageCreate() of the UIAbility to dynamically request user authorization, or request user authorization on the UI based on service requirements.

Sample code for requesting user authorization using UIAbility:

import UIAbility from '@ohos.app.ability.UIAbility';
import window from '@ohos.window';
import abilityAccessCtrl, { Permissions } from '@ohos.abilityAccessCtrl';

const permissions: Array<Permissions> = ['ohos.permission.READ_CALENDAR'];

export default class EntryAbility extends UIAbility {
  // ...

  onWindowStageCreate(windowStage: window.WindowStage) {
    // Main window is created. Set the main page for this ability.
    let context = this.context;
    let atManager = abilityAccessCtrl.createAtManager();
    // The return value of requestPermissionsFromUser determines whether to display a dialog box to request user authorization.

    atManager.requestPermissionsFromUser(context, permissions).then((data) => {
      let grantStatus: Array<number> = data.authResults;
      let length: number = grantStatus.length;
      for (let i = 0; i < length; i++) {
        if (grantStatus[i] === 0) {
          // If the user has granted the permission, the application can access the Calendar.
        } else {
          // If the user has not granted the permission, display a message indicating that user authorization is required, and direct the user to the Settings page to set the permission.
          return;
        }
      }
      // The authorization is successful.
    }).catch((err) => {
      console.error(`Failed to request permissions from user. Code is ${err.code}, message is ${err.message}`);

    // ...
  }
}

Sample code for requesting user authorization on the UI:

import abilityAccessCtrl, { Permissions } from '@ohos.abilityAccessCtrl';
import common from '@ohos.app.ability.common';

const permissions: Array<Permissions> = ['ohos.permission.READ_CALENDAR'];

@Entry
@Component
struct Index {
  reqPermissionsFromUser(permissions: Array<Permissions>): void {
    let context = getContext(this) as common.UIAbilityContext;
    let atManager = abilityAccessCtrl.createAtManager();
    // The return value of requestPermissionsFromUser determines whether to display a dialog box to request user authorization.
    atManager.requestPermissionsFromUser(context, permissions).then((data) => {
      let grantStatus: Array<number> = data.authResults;
      let length: number = grantStatus.length;
      for (let i = 0; i < length; i++) {
        if (grantStatus[i] === 0) {
          // If the user has granted the permission, the application can access the Calendar.
        } else {
          // If the user has not granted the permission, display a message indicating that user authorization is required, and direct the user to the Settings page to set the permission.
          return;
        }
      }
      // The authorization is successful.
    }).catch((err) => {
      console.error(`Failed to request permissions from user. Code is ${err.code}, message is ${err.message}`);
    })
  }

  // Page display.
  build() {
    // ...
  }
}

Perform subsequent operations based on the authorization result.

After requestPermissionsFromUser() is called, the application waits for the user authorization result. If the user has granted the permission, the application can access the Calendar. If the user has not granted the permission, a message will be displayed indicating that user authorization is required, and the user is directed to Settings to set the permission.

function openPermissionsInSystemSettings(): void {
  let context = getContext(this) as common.UIAbilityContext;
  let wantInfo = {
    action: 'action.settings.app.info',
    parameters: {
      settingsParamBundleName: 'com.example.myapplication' // Open the Details page of the application.
    }
  }
  context.startAbility(wantInfo).then(() => {
    // ...
  }).catch((err) => {
    // ...
  })
}

FA Model

Call requestPermissionsFromUser() to request user authorization.

import featureAbility from '@ohos.ability.featureAbility';

reqPermissions() {
    let context = featureAbility.getContext();
    let array:Array<string> = ["ohos.permission.PERMISSION2"];
    // The return value of requestPermissionsFromUser determines whether to display a dialog box to request user authorization.
    context.requestPermissionsFromUser(array, 1).then(function(data) {
        console.log("data:" + JSON.stringify(data));
        console.log("data permissions:" + JSON.stringify(data.permissions));
        console.log("data result:" + JSON.stringify(data.authResults));
    }, (err) => {
        console.error('Failed to start ability', err.code);
    });
}

Pre-authorizing user_grant Permissions

By default, the user_grant permissions must be dynamically authorized by the user through a dialog box. However, some pre-installed applications may require user_grant permissions, for example, the system camera application requires the ohos.permission.MICROPHONE permission. In this case, you can pre-authorize user_grant permissions for pre-installed applications in the install_list_permission.json file. The install_list_permissions.json file is in the /system/etc/app/ directory on a device, and is loaded when the device starts. When the application is installed, the user_grant permissions in the file are granted.

The install_list_permissions.json file contains the following fields:

bundleName: bundle name of the application.
app_signature: fingerprint information of the application. For details, see Configuration in install_list_capability.json in the Application Privilege Configuration Guide.
permissions: The name field specifies the name of the user_grant permission to pre-authorize. The userCancellable field specifies whether the user can revoke the pre-authorization. The value true means the user can revoke the pre-authorization; the value false means the opposite.

NOTE

The install_list_permissions.json file is available only for preinstalled applications.

[
  // ...
  {
    "bundleName": "com.example.myapplication", // Bundle Name.
    "app_signature": ["****"], // Fingerprint information.
    "permissions":[
      {
        "name": "ohos.permission.PERMISSION_X", // Permission to pre-authorize.
        "userCancellable": false // The user cannot revoke the authorization.
      },
      {
        "name": "ohos.permission.PERMISSION_X", // Permission to pre-authorize.
        "userCancellable": true // The user can revoke the authorization.
      }
    ]
  }
]