Refactor overhaul, data extensions & Resend.com support

1 files changed, 160 insertions, 0 deletions

diff --git a/lib/Emails.Transactional.Plugin/src/Endpoints/SendEndpoint.cs b/lib/Emails.Transactional.Plugin/src/Endpoints/SendEndpoint.cs
new file mode 100644
index 0000000..3e6f940
--- /dev/null
+++ b/lib/Emails.Transactional.Plugin/src/Endpoints/SendEndpoint.cs
@@ -0,0 +1,160 @@
+/*
+* Copyright (c) 2023 Vaughn Nugent
+* 
+* Library: VNLib
+* Package: Emails.Transactional
+* File: SendEndpoint.cs 
+*
+* SendEndpoint.cs is part of Emails.Transactional which is part of the larger 
+* VNLib collection of libraries and utilities.
+*
+* Emails.Transactional is free software: you can redistribute it and/or modify 
+* it under the terms of the GNU General Public License as published
+* by the Free Software Foundation, either version 2 of the License,
+* or (at your option) any later version.
+*
+* Emails.Transactional is distributed in the hope that it will be useful,
+* but WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 
+* General Public License for more details.
+*
+* You should have received a copy of the GNU General Public License 
+* along with Emails.Transactional. If not, see http://www.gnu.org/licenses/.
+*/
+
+
+using System;
+using System.Net;
+using System.Threading.Tasks;
+
+using VNLib.Utils.Logging;
+using VNLib.Plugins;
+using VNLib.Plugins.Essentials;
+using VNLib.Plugins.Essentials.Extensions;
+using VNLib.Plugins.Essentials.Oauth;
+using VNLib.Plugins.Extensions.Validation;
+using VNLib.Plugins.Extensions.Loading;
+using VNLib.Plugins.Extensions.Loading.Sql;
+using VNLib.Plugins.Extensions.Data.Extensions;
+
+using Emails.Transactional.Mta;
+using Emails.Transactional.Templates;
+using Emails.Transactional.Transactions;
+
+namespace Emails.Transactional.Endpoints
+{
+
+    [ConfigurationName("send_endpoint")]
+    internal class SendEndpoint : O2EndpointBase
+    {
+        public const string OAUTH2_USER_SCOPE_PERMISSION = "email:send";
+
+        private static readonly EmailTransactionValidator Validator = new();
+
+        private readonly string FromAddress;
+       
+        private readonly TransactionStore Transactions;
+        private readonly IMailTransferAgent EmailService;
+        private readonly ITemplateStorage Templates;
+
+        public SendEndpoint(PluginBase plugin, IConfigScope config)
+        {
+            string? path = config["path"].GetString();
+            FromAddress = config.GetRequiredProperty("from_address", e => e.GetString()!);
+
+            InitPathAndLog(path, plugin.Log);
+
+            //Load transactions
+            Transactions = new(plugin.GetContextOptions());
+
+            //init ail transfer agent
+            EmailService = plugin.GetOrCreateSingleton<MailTransferAgent>();
+
+            //Load templates
+            Templates = plugin.GetOrCreateSingleton<EmailTemplateStore>();
+        }
+
+        protected override async ValueTask<VfReturnType> PostAsync(HttpEntity entity)
+        {
+            //Make sure the user has the required scope to send an email
+            if (!entity.Session.HasScope(OAUTH2_USER_SCOPE_PERMISSION))
+            {
+                entity.CloseResponseError(HttpStatusCode.Forbidden, ErrorType.InvalidScope, "Your account does not have the required permissions scope");
+                return VfReturnType.VirtualSkip;
+            }
+
+            //Get the transaction request from the client
+            EmailTransaction? transaction = await entity.GetJsonFromFileAsync<EmailTransaction>();
+
+            if(transaction == null)
+            {
+                entity.CloseResponseError(HttpStatusCode.BadRequest, ErrorType.InvalidRequest, "No request body was received");
+                return VfReturnType.VirtualSkip;
+            }
+                        
+            TransactionResult webm = new()
+            {
+                Success = false
+            };
+
+            //Set a default from name/address if not set by user
+            transaction.From ??= FromAddress;
+            transaction.FromName ??= FromAddress;
+
+            //Specify user-id
+            transaction.UserId = entity.Session.UserID;
+
+            //validate the form
+            if (!Validator.Validate(transaction, webm))
+            {
+                //return errors
+                entity.CloseResponseJson(HttpStatusCode.UnprocessableEntity, webm);
+                return VfReturnType.VirtualSkip;
+            }
+
+            //Always add the template name to the model
+            transaction.Variables!["template_name"] = transaction.TemplateId!;
+
+            try
+            {
+                //Get the template
+                IEmailTemplate template = await Templates.GetTemplateAsync(transaction.TemplateId!, entity.EventCancellation);
+
+                //Render the template with the model
+                IEmailMessageData message = template.RenderTemplate(transaction.Variables!);
+
+                //Send the template
+                MtaResult result = await EmailService.SendEmailAsync(transaction, message, entity.EventCancellation);
+
+                //Set success flag
+                webm.Success = result.Success;
+                webm.SmtpStatus = result.Message;
+            }
+            //Handle a template lookup failure
+            catch(TemplateLookupFailedException ex)
+            {
+                Log.Debug("Failed to fetch template: {err}", transaction.TemplateId, ex.Message);
+
+                entity.CloseResponseError(HttpStatusCode.NotFound, ErrorType.InvalidRequest, "The requested template does not exist");
+                return VfReturnType.VirtualSkip;
+            }
+            catch (Exception ex)
+            {
+                Log.Error(ex);
+
+                //Write an error status message to the transaction store
+                webm.SmtpStatus = transaction.Result = ex.Message;
+            }
+
+            //Write transaction to db (we need to return the transaction id)
+            _ = await Transactions.AddOrUpdateAsync(transaction, entity.EventCancellation);
+
+            //Store the results object
+            webm.TransactionId = transaction.Id;
+
+            //Return the response object
+            entity.CloseResponse(webm);
+            return VfReturnType.VirtualSkip;
+        }
+    }
+}