Handlebars.Net ITemplateRenderer for FluentEmail. Works best as a singleton as it will compile and store each template passed in

HandlebarsRenderer.cs

using System.Security.Cryptography;
using System.Text;
using System.Threading.Tasks;
using FluentEmail.Core.Interfaces;
using HandlebarsDotNet;

namespace FluentEmail.Renderers
{
    public class HandlebarsRenderer : ITemplateRenderer
    {
        private readonly IHandlebars _handlebars;

        private readonly Dictionary<string, Func<object, string>> _compiledTemplates = new Dictionary<string, Func<object, string>>();

        public HandlebarsRenderer(IHandlebars handlebars) {
            _handlebars = handlebars;
        }

        public string Parse<T>(string template, T model, bool isHtml = true) {
            return ParseAsync(template, model, isHtml).GetAwaiter().GetResult();
        }

        public Task<string> ParseAsync<T>(string template, T model, bool isHtml = true) {
            string templateHash = GetHashString(template);

            Func<object, string> compiledTemplate = null;
            if (!_compiledTemplates.ContainsKey(templateHash)) {
                _compiledTemplates.Add(templateHash, _handlebars.Compile(template));
            }

            compiledTemplate = _compiledTemplates[templateHash];

            return Task.Factory.StartNew(() => compiledTemplate(model));
        }

        private static string GetHashString(string inputString)
        {
            StringBuilder sb = new StringBuilder();
            var hashbytes = SHA256.Create().ComputeHash(Encoding.UTF8.GetBytes(inputString));
            foreach (byte b in hashbytes)
            {
                sb.Append(b.ToString("X2"));
            }

            return sb.ToString();
        }
    }
}

Excellent! A lot more lightweight than adding all the razor deps to my MVC webapi :)