invite.js

// in invite.js module:
exports.inviteUser = function(creatingUser,email,tempPass,response)
{
  "use strict";
    if (!tempPass) {                         
        tempPass = genRandomPass();
    }

    var user = new Parse.User();
    user.set ("username", email);
    user.set ("password", tempPass);
    user.set ("email", email);
    // TODO: set other user properties. Only the invited user can change them
    // after the user has been created.

    user.signUp(null, {
        success: function(createdUser) {
            sendInvitationEmail(email, subject, tempPass, {
                    success: function(httpResponse) {
                        console.log("User " + createdUser.id + " created, and sent email: " + httpResponse.status);
                        response.success(createdUser);
                    },
                    error: function (httpResponse) {
                        console.error("user "+ createdUser.id +" created, but couldn't email them. " + httpResponse.status + " " + httpResponse.text);
                        response.error("user "+ createdUser.id +" created, but couldn't email them. " + httpResponse.status);
                    }
                 });
            }
        },
        error: function(user,error) {
            response.error("parse error: couldn't create user " + error.code + " " + error.message);
        }	   
    });
    
};

function sendInvitationEmail(email,subject,tempPass,callbackObject) {
    "use strict";
    var sendgrid = require("sendgrid");
    var secrets = require("cloud/secrets.js");
	sendgrid.initialize(secrets.sendgriduser, secrets.sendgridpw); // TODO: your creds here...
	
	var fromname = "My Service";
	var from = "noreply@myservice.com";
	var subject = "Welcome to My Service";
	var template = "hello {email} your temporary password is {pass}" ;
    var emailText = template.replace(/{email}/g,email).replace(/{pass}/g,tempPass);
    
    sendgrid.sendEmail({
        to: email,
        from: from,
    fromname: fromname,
        subject: subject,
        text: emailText,
        
    }, callbackObject);
}

function genRandomPass() {
    return "1223"; // TODO: generate a password using a random pw generator
}

main.js

// in main.js:
Parse.Cloud.define("inviteUser", function(request, response)
{  
  var creatingUser = request.user; 
  var email = request.params.email; // string required
	var tempPass = request.params.password; // string

    var invitejs = require("cloud/invite.js");
    invitejs.inviteUser(creatingUser,email,tempPass,response);
 
 });