Rating Scale - add in custom DispForm.aspx?

Question

I enabled the Rating Scale on a list and it works well on list view. But, is there a way to add it in custom DispForm.aspx while enabling user to rate it dynamically when DispForm is opened? It shows on default DispForm.aspx but not when I create a custom one.

I also read this post but need to research more about PnP and how I could use the solution posted.

Edit 4/11/19

I found this post but could not figure out how to modify the following within my scenario. My list name is Training where I enabled the rating system. Below is what I have so far, the GetRating() works but I still can't get the SetRating() to work.

The code is in txt file and linked in a CEWP located below the main DispForm.aspx contents.

I started with

$(document).ready(function () {
    ExecuteOrDelayUntilScriptLoaded(GetRating, "sp.js");
});

Modified GetRating function:

function GetRating() {

var listUri = _spPageContextInfo.webServerRelativeUrl;
var itemID = GetUrlKeyValue("ID", false, location.href);
var spCtx = new SP.ClientContext(listUri);
var list = spCtx.get_web().get_lists().getByTitle("Training");

if(itemID > 0 ) {
    this.itemRating= list.getItemById(itemID);
    spCtx.load(itemRating);
    spCtx.executeQueryAsync (
        Function.createDelegate(this, this.onQuerySucceeded), 
        Function.createDelegate(this, this.onQueryFailed)
    );
}  
}

Modified SetRating function that does not work. It doesn't give any error messages.

function SetRating(rValue) {
var listUri = _spPageContextInfo.webServerRelativeUrl;
var itemID = GetUrlKeyValue("ID", false, location.href);
var listGUIDURL = listUri +"/_api/web/lists/getByTitle('Training')?&select=Id";
//var listGUID = "";
var listGUID = _spPageContextInfo.pageListId;

$.ajax({        
    url: listGUIDURL,
    method: "GET",
    headers: { "Accept": "application/json; odata=verbose" },
    success: function (data) {
        if (data.d.Id != "") {   
            //listGUID = data.d.Id; 
            var spCtx = new SP.ClientContext(listUri);
            EnsureScriptFunc('reputation.js', 'Microsoft.Office.Server.ReputationModel.Reputation', function () {
                Microsoft.Office.Server.ReputationModel.Reputation.setRating(spCtx, listGUID, itemID, rValue);
                spCtx.executeQueryAsync(
                    function() {
                        SP.UI.Notify.addNotification("Thank you for rating.", false);
                        GetRating();
                    }, function() {
                        SP.UI.Notify.addNotification("There was an error saving.", false);                         
                });
            });
        }
    }, 
    error: function (data) { console.log("Failed to set rating"); }
});
}

When using the original code (without EnsureScriptFunc line, it gives an error message Uncaught TypeError: Cannot read property 'Server' of undefined. Using this reference, I added EnsureScriptFunc... which no longer gives an error message but it doesn't do anything.

I also added the following in my master HTML:

<!--SPM:<SharePoint:ScriptLink ID="ScriptLink6" name="SP.js" runat="server" ondemand="false" localizable="false" loadafterui="true" />-->
<!--SPM:<SharePoint:ScriptLink ID="ScriptLink8" name="SP.Core.js" runat="server" ondemand="false" localizable="false" loadafterui="true" />-->
<!--SPM:<SharePoint:ScriptLink ID="ScriptLink9" name="Reputation.js" runat="server" ondemand="false" localizable="false" loadafterui="true" />-->

Answer 1

I finally got this to work. Rather than adding the links in my master HTML, I added the following SP.SOD... in:

$(document).ready(function () {
ExecuteOrDelayUntilScriptLoaded(GetRating, "sp.js");
SP.SOD.registerSod('reputation.js', '/_layouts/15/reputation.js');
SP.SOD.executeFunc('reputation.js', 'Microsoft.Office.Server.ReputationModel.Reputation', function () {
    SP.SOD.executeFunc('sp.js', 'SP.ClientContext', GetRating);
});
});

Source:

• Add a Like/Ratings Button to the SharePoint Item Display Form (DispForm.aspx) to Allow Users to Like an Item from that page