add emailService to handle email sending

app/services/emailService.js

@@ -0,0 +1,56 @@
+"use strict";
+
+let AWS = require("aws-sdk");
+const htmlToText = require("html-to-text");
+
+const { AWS_EMAIL_CONFIG } = require("../config/appConfig");
+
+AWS.config.update({
+  region: AWS_EMAIL_CONFIG.REGION,
+  credentials: {
+    accessKeyId: AWS_EMAIL_CONFIG.CREDENTIALS.ACCESS_KEY_ID,
+    secretAccessKey: AWS_EMAIL_CONFIG.CREDENTIALS.SECRET_ACCESS_KEY
+  }
+});
+
+const awsMailer = new AWS.SES({ apiVersion: "2010-12-01" });
+
+const sendEmail = async (to, subject, message, from) => {
+  const params = {
+    Destination: {
+      ToAddresses: [to]
+    },
+    Message: {
+      Subject: {
+        Charset: "UTF-8",
+        Data: subject
+      },
+      Body: {
+        Html: {
+          Charset: "UTF-8",
+          Data: message
+        },
+        Text: {
+          Charset: "UTF-8",
+          Data: htmlToText.fromString(message)
+        }
+      }
+    },
+    ReturnPath: from ? from : AWS_EMAIL_CONFIG.SOURCE_EMAIL,
+    Source: from ? from : AWS_EMAIL_CONFIG.SOURCE_EMAIL
+  };
+
+  return new Promise((resolve, reject) => {
+    awsMailer.sendEmail(params, (error, data) => {
+      if (error) {
+        reject(error);
+      } else {
+        resolve(data);
+      }
+    });
+  });
+};
+
+module.exports = {
+  sendEmail
+};