Retrieve operation with Xrm.WebApi.online.execute

xrm-webapi-online-execute-retrieve.js

var Sdk = window.Sdk || {};

/**
 * Request to update a record
 * @param {Object} entityReference - The entity reference.
 * @param {Array} columns - The columns.
 */
Sdk.RetrieveRequest = function (entityReference, columns) {
    this.entityReference = entityTypeName;
    this.columns = columns;
    this.getMetadata = function () {
        return {
            boundParameter: null,
            parameterTypes: {},
            operationType: 2,
            operationName: "Retrieve",
        };
    };
};

// Construct a request object from the metadata
var request = new Sdk.RetrieveRequest({ etn: "new_entity", id: "00000000-0000-0000-0000-000000000000" }, ["new_name"]);

// Use the request object to execute the function
Xrm.WebApi.online.execute(request).then(
    (result) => {
        if (result.ok) {
            console.log(`${result.status} ${result.statusText}`);
        }
    },
    (error) => {
        console.log(error.message);
    }
);