Share document to multiple users using REST api in SharePoint 2013

Below is the REST call using JavaScript code that shares a document from a SharePoint hosted app.

function shareDocument()
{
    var hostweburl = decodeURIComponent(getQueryStringParameter('SPHostUrl'));
    var appweburl = decodeURIComponent(getQueryStringParameter('SPAppWebUrl'));
    var restSource = appweburl + "/_api/SP.Sharing.DocumentSharingManager.UpdateDocumentSharingInfo";


    $.ajax(
    {
        'url': restSource,
        'method': 'POST',
        'data': JSON.stringify({
            'resourceAddress': 'http://basesmc15/Shared%20Documents/A1210251607172880165.pdf',
            'userRoleAssignments': [{
                '__metadata': {
                    'type': 'SP.Sharing.UserRoleAssignment'
                },
                'Role': 1,
                'UserId': 'Chris Tester'
            }],
            'validateExistingPermissions': false,
            'additiveMode': true,
            'sendServerManagedNotification': false,
            'customMessage': "Please look at the following document",
            'includeAnonymousLinksInNotification': false
        }),
        'headers': {
            'accept': 'application/json;odata=verbose',
            'content-type': 'application/json;odata=verbose',
            'X-RequestDigest': $('#__REQUESTDIGEST').val()
        },
        'success': function (data) {
            var d = data;
        },
        'error': function (err) {
            alert(JSON.stringify(err));
        }
    }
    );

}

ResourceAddress: This is the full URL to the document you want to share

UserRoleAssignments: This an array of users and roles that you want to share the document with. The Role property represents which permission you are assigning. 1 = View, 2 = Edit, 3 = Owner, 0 = None. The UserId property can be the name of the user or a role. For example, if you wanted to share the document with the “Translation Mangers” role and the “Steve Tester” user you would use this JSON:

'userRoleAssignments': [{
                '__metadata': {
                    'type': 'SP.Sharing.UserRoleAssignment'
                },
                'Role': 1,
                'UserId': 'Translation Managers'
            },
            {
                '__metadata': {
                    'type': 'SP.Sharing.UserRoleAssignment'
                },
                'Role': 1,
                'UserId': 'Steve Tester'
            }]

Sharing Documents with the SharePoint REST API by Steve Curran