Reusable Xperience Email Transformations

EmailMacroMethodContainer.cs

using System;
using System.Collections.Generic;
using System.Linq;
using CMS;
using CMS.Helpers;
using CMS.MacroEngine;
using CMS.PortalEngine;
using CMS.SiteProvider;
using Sandbox.Infrastructure.Emails;

[assembly: RegisterExtension(typeof(EmailMacroMethodContainer), typeof(StringNamespace))]

namespace Sandbox.Infrastructure.Emails
{
    public class EmailMacroMethodContainer : MacroMethodContainer
    {
        /// <summary>
        /// Returns the live site domain
        /// </summary>
        /// <param name="_">Evaluation context with child resolver</param>
        /// <param name="parameters">Method parameters</param>
        [MacroMethod(typeof(string), "Returns live site domain", 0)]
        public static object SiteLinkDomain(EvaluationContext _, params object[] parameters)
        {
            switch (parameters.Length)
            {
                case 0:
                    return SiteInfoProvider.GetSiteInfo(SiteContext.CurrentSiteID)?.SitePresentationURL ?? "";

                default:
                    throw new NotSupportedException();
            }
        }

        /// <summary>
        /// Evaluates the provided transformation without a data context and returns the transformation content
        /// with all macros resolved
        /// </summary>
        /// <param name="context"></param>
        /// <param name="parameters"></param>
        /// <returns></returns>
        [MacroMethod(typeof(string), "Returns the provided transformation evaluated 1 time without a data context", 1)]
        public static object ApplySimpleTransformation(EvaluationContext context, params object[] parameters)
        {
            switch (parameters.Length)
            {
                case 1:
                    string content = GetTransformationCode(GetStringParam(parameters[0], context.Culture));

                    var bodyResolver = context.Resolver.CreateChild();

                    return bodyResolver.ResolveMacros(content, context);

                default:
                    throw new NotSupportedException();
            }
        }

        private static string GetTransformationCode(string transformation)
        {
            // Try to load transformation code
            var ti = TransformationInfoProvider.GetTransformation(transformation);
            if (ti != null)
            {
                switch (ti.TransformationType)
                {
                    case TransformationTypeEnum.Text:
                    case TransformationTypeEnum.Html:

                        // Return transformation code
                        return ti.TransformationCode;

                    default:

                        // Not supported transformation type
                        throw new NotSupportedException("[MacroMethods.ApplyTransformation]: Only text/html transformation is supported.");
                }
            }

            // Return input text
            return transformation;
        }
    }
}

EmailTemplate.html

{% ApplySimpleTransformation("Sandbox.Transformations.EmailCompanyHeader")|(encode)false #%}

<tr>
  <td style="padding: 40px 20px;">
    <p style="color: #000; margin: 8px 0 0; padding: 0;">
       {% Greeting %}, <a href="{% SiteLinkDomain() %}" target="_blank">Click this link to visit our site</a>
    </p>
  </td>
</tr>

{% ApplySimpleTransformation("Sandbox.Transformations.EmailCompanyFooter")|(encode)false #%}