Working with Site Permissions

When a website wants to access certain services on a user’s device, it will send out a permissions request. This document will explain how to use GeckoView to receive those requests, and respond to them by granting or denying those permissions.

The Permission Delegate 

The way an app interacts with site permissions in GeckoView is through the PermissionDelegate. There are three broad categories of permission that the PermissionDelegate handles, Android Permissions, Content Permissions and Media Permissions. All site permissions handled by GeckoView fall into one of these three categories.

To get notified about permission requests, you need to implement the PermissionDelegate interface:

private class ExamplePermissionDelegate implements GeckoSession.PermissionDelegate {
    @Override
    public void onAndroidPermissionsRequest(final GeckoSession session,
                                            final String[] permissions,
                                            final Callback callback) { }

    @Override
    public void onContentPermissionRequest(final GeckoSession session,
                                           final String uri,
                                           final int type, final Callback callback) { }

    @Override
    public void onMediaPermissionRequest(final GeckoSession session,
                                         final String uri,
                                         final MediaSource[] video,
                                         final MediaSource[] audio,
                                         final MediaCallback callback) { }
}

You will then need to register the delegate with your GeckoSession instance.

public class GeckoViewActivity extends AppCompatActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        ...

        final ExamplePermissionDelegate permission = new ExamplePermissionDelegate();
        session.setPermissionDelegate(permission);

        ...
    }
}

Android Permissions 

Android permissions are requested whenever a site wants access to a device’s navigation or input capabilities.

The user will often need to grant these Android permissions to the app alongside granting the Content or Media site permissions.

When you receive an onAndroidPermissionsRequest call, you will also receive the GeckoSession the request was sent from, an array containing the permissions that are being requested, and a Callback to respond to the request. It is then up to the app to request those permissions from the device, which can be done using requestPermissions.

Possible permissions values are: ACCESS_COARSE_LOCATION, ACCESS_FINE_LOCATION, CAMERA or RECORD_AUDIO.

private class ExamplePermissionDelegate implements GeckoSession.PermissionDelegate {
    private Callback mCallback;

    public void onRequestPermissionsResult(final String[] permissions,
                                           final int[] grantResults) {
        if (mCallback == null) { return; }

        final Callback cb = mCallback;
        mCallback = null;
        for (final int result : grantResults) {
            if (result != PackageManager.PERMISSION_GRANTED) {
                // At least one permission was not granted.
                cb.reject();
                return;
            }
        }
        cb.grant();
    }

    @Override
    public void onAndroidPermissionsRequest(final GeckoSession session,
                                            final String[] permissions,
                                            final Callback callback) {
        mCallback = callback;
        requestPermissions(permissions, androidPermissionRequestCode);
    }
}

public class GeckoViewActivity extends AppCompatActivity {
    @Override
    public void onRequestPermissionsResult(final int requestCode,
                                           final String[] permissions,
                                           final int[] grantResults) {
        if (requestCode == REQUEST_PERMISSIONS ||
            requestCode == REQUEST_WRITE_EXTERNAL_STORAGE) {
            final ExamplePermissionDelegate permission = (ExamplePermissionDelegate)
                    getCurrentSession().getPermissionDelegate();
            permission.onRequestPermissionsResult(permissions, grantResults);
        } else {
            super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        }
    }
}

Content Permissions 

Content permissions are requested whenever a site wants access to content that is stored on the device. The content permissions that can be requested through GeckoView are: Geolocation, Site Notifications, Persistent Storage, XR, Autoplay Inaudible, Autoplay Audible, and DRM Media access. Additionally, tracking protection exceptions are treated as a type of content permission.

When you receive an onContentPermissionRequest call, you will also receive the GeckoSession the request was sent from, and all relevant information about the permission being requested stored in a ContentPermission. It is then up to the app to present UI to the user asking for the permissions, and to notify GeckoView of the response via the returned GeckoResult.

Once a permission has been set in this fashion, GeckoView will persist it across sessions until it is cleared or modified. When a page is loaded, the active permissions associated with it (both allowed and denied) will be reported in onLocationChange as a list of ContentPermission objects; additionally, one may check all stored content permissions by calling getAllPermissions and the content permissions associated with a given URI by calling getPermissions. In order to modify an existing permission, you will need the associated ContentPermission (which can be retrieved from any of the above methods); then, call setPermission with the desired new value, or VALUE_PROMPT if you wish to unset the permission and let the site request it again in the future.

Media Permissions 

Media permissions are requested whenever a site wants access to play or record media from the device’s camera and microphone.

When you receive an onMediaPermissionRequest call, you will also receive the GeckoSession the request was sent from, the URI of the site that requested the permission, as a String, the list of video devices available, if requesting video, the list of audio devices available, if requesting audio, and a MediaCallback to respond to the request.

It is up to the app to present UI to the user asking for the permissions, and to notify GeckoView of the response via the MediaCallback.

Please note, media permissions will still be requested if the associated device permissions have been denied if there are video or audio sources in that category that can still be accessed when listed. It is the responsibility of consumers to ensure that media permission requests are not displayed in this case.

private class ExamplePermissionDelegate implements GeckoSession.PermissionDelegate {
    @Override
    public void onMediaPermissionRequest(final GeckoSession session,
                                         final String uri,
                                         final MediaSource[] video,
                                         final MediaSource[] audio,
                                         final MediaCallback callback) {
        // Reject permission if Android permission has been previously denied.
        if ((audio != null
                && ContextCompat.checkSelfPermission(GeckoViewActivity.this,
                    Manifest.permission.RECORD_AUDIO) != PackageManager.PERMISSION_GRANTED)
            || (video != null
                && ContextCompat.checkSelfPermission(GeckoViewActivity.this,
                    Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED)) {
            callback.reject();
            return;
        }

        final String host = Uri.parse(uri).getAuthority();
        final String title;
        if (audio == null) {
            title = getString(R.string.request_video, host);
        } else if (video == null) {
            title = getString(R.string.request_audio, host);
        } else {
            title = getString(R.string.request_media, host);
        }

        // Get the media device name from the `MediaDevice`
        String[] videoNames = normalizeMediaName(video);
        String[] audioNames = normalizeMediaName(audio);

        final AlertDialog.Builder builder = new AlertDialog.Builder(activity);

        // Create drop down boxes to allow users to select which device to grant permission to
        final LinearLayout container = addStandardLayout(builder, title, null);
        final Spinner videoSpinner;
        if (video != null) {
            videoSpinner = addMediaSpinner(builder.getContext(), container, video, videoNames); // create spinner and add to alert UI
        } else {
            videoSpinner = null;
        }

        final Spinner audioSpinner;
        if (audio != null) {
            audioSpinner = addMediaSpinner(builder.getContext(), container, audio, audioNames); // create spinner and add to alert UI
        } else {
            audioSpinner = null;
        }

        builder.setNegativeButton(android.R.string.cancel, null)
               .setPositiveButton(android.R.string.ok,
                                  new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(final DialogInterface dialog, final int which) {
                        // gather selected media devices and grant access
                        final MediaSource video = (videoSpinner != null)
                                ? (MediaSource) videoSpinner.getSelectedItem() : null;
                        final MediaSource audio = (audioSpinner != null)
                                ? (MediaSource) audioSpinner.getSelectedItem() : null;
                        callback.grant(video, audio);
                    }
                });

        final AlertDialog dialog = builder.create();
        dialog.setOnDismissListener(new DialogInterface.OnDismissListener() {
                    @Override
                    public void onDismiss(final DialogInterface dialog) {
                        callback.reject();
                    }
                });
        dialog.show();
    }
}

To see the PermissionsDelegate in action, you can find the full example implementation in the GeckoView example app.

Working with Site Permissions

The Permission Delegate

Android Permissions

Content Permissions

Media Permissions

The Permission Delegate 

Android Permissions 

Content Permissions 

Media Permissions 