Microsoft Dynamics 365: Combining HTML & JavaScript to restrict entity access

function onLoad() {

    var myTeamId = null;

    var myTeamName = null;

    //the user is not part of the team by default until it is checked

    let isPartOfTeam = false;

    var guid = "[A-z0-9]{8}-[A-z0-9]{4}-[A-z0-9]{4}-[A-z0-9]{4}-[A-z0-9]{12}";

    var serverUrl = Xrm.Page.context.getClientUrl();

    var userId = Xrm.Page.context.getUserId();

    userId = userId.match(guid);

    userId = userId.input;

    //retrieve teamIds of the teams current user belongs to

    var userTeamsQuery = "TeamMembershipSet?$select=TeamId&$filter=SystemUserId eq guid'" + userId + "'";

    var userTeams = makeRequest(userTeamsQuery);

    var teamQuery = null;

    var teams = null;

    if (userTeams !== null) {

        for (var i = 0; i < userTeams.length; i++) {

            userTeams[i] = userTeams[i].TeamId;

            var teamId = "{" + userTeams[i] + "}";

            //retrieve name and teamIds of the teams via given teamId that we already have above

            teamQuery = "TeamSet?$select=Name, TeamId&$filter=TeamId eq guid'" + teamId + "'";

            teams = makeRequest(teamQuery);

            myTeamId = teamId;

            if (teams !== null && teams.length > 0) {

                myTeamName = teams[0].Name;

                //valuating the isPartOfTeam variable as true if user is part of target team

                if (myTeamName == "Team 1") {

                    isPartOfTeam = true;

                    break;
                }
            }
        }
        //condition to check if user is not part of target team and opening the HTML web resource page

        if (isPartOfTeam == false) {

            var pageParameters = {

                pageType: "webresource", //the HTML page is a web resource type in this case

                webresourceName: "fisoft_htmlPage", //logical name of the HTML web resource you would like to open

            };
            var navigationOptions = {
                target: 1, //value 1 to open the targeted web resource in fullscreen
            };

            //Xrm method that executes the web resource by taking as parameters the variables assigned above

            Xrm.Navigation.navigateTo(pageParameters, navigationOptions);
        }
    }
}

function getRequestObject() {

    if (window.XMLHttpRequest) {

        return new window.XMLHttpRequest;
    } else {
        try {
            return new ActiveXObject("MSXML2.XMLHTTP.3.0");
        } catch (ex) {
            return null;
        }
    }
}
function makeRequest(query) {

    var serverUrl = Xrm.Page.context.getClientUrl();

    var oDataEndpointUrl = serverUrl + "/XRMServices/2011/OrganizationData.svc/";

    oDataEndpointUrl += query;

    var service = getRequestObject();

    if (service != null) {

        service.open("GET", oDataEndpointUrl, false);

        service.setRequestHeader("X-Requested-With", "XMLHttpRequest");

        service.setRequestHeader("Accept", "application/json, text/javascript, */*");

        service.send(null);

        var retrieved = JSON.parse(service.responseText).d;

        var results = new Array();

        for (var i = 0; i < retrieved.results.length; i++) {

            results.push(retrieved.results[i]);
        }
        return results;
    }
    return null;
}

//valuating the isPartOfTeam variable as true if user is part of target team
                if (myTeamName == "Team 1") {
                    isPartOfTeam = true;
                    break;
                }

//condition to check if user is not part of target team and opening the HTML web resource page
        if (isPartOfTeam == false) {

            var pageParameters = {
                pageType: "webresource", //the HTML page is a web resource type in this case
                webresourceName: "fisoft_htmlPage", //logical name of the HTML web resource you would like to open
            };
            var navigationOptions = {
                target: 1, //value 1 to open the targeted web resource in fullscreen
            };
            //Xrm method that executes the web resource by taking as parameters the variables assigned above
            Xrm.Navigation.navigateTo(pageParameters, navigationOptions);
        }