fix(backend): do not throw when email exists on registration

backend/src/middleware/login/loginMiddleware.js

@@ -10,10 +10,13 @@ const sendSignupMail = async (resolve, root, args, context, resolveInfo) => {
   const { inviteCode } = args
   const response = await resolve(root, args, context, resolveInfo)
   const { email, nonce } = response
-  if (inviteCode) {
-    await sendMail(signupTemplate({ email, variables: { nonce, inviteCode } }))
-  } else {
-    await sendMail(signupTemplate({ email, variables: { nonce } }))
+  if (nonce) {
+    // emails that already exist do not have a nonce
+    if (inviteCode) {
+      await sendMail(signupTemplate({ email, variables: { nonce, inviteCode } }))
+    } else {
+      await sendMail(signupTemplate({ email, variables: { nonce } }))
+    }
   }
   delete response.nonce
   return response

backend/src/schema/resolvers/helpers/existingEmailAddress.js

@@ -1,5 +1,3 @@
-import { UserInputError } from 'apollo-server'
-
 export default async function alreadyExistingMail({ args, context }) {
   const session = context.driver.session()
   try {
@@ -20,9 +18,11 @@ export default async function alreadyExistingMail({ args, context }) {
       })
     })
     const [emailBelongsToUser] = await existingEmailAddressTxPromise
-    const { alreadyExistingEmail, user } = emailBelongsToUser || {}
-    if (user) throw new UserInputError('A user account with this email already exists.')
-    return alreadyExistingEmail
+    /*
+      const { alreadyExistingEmail, user } = 
+      if (user) throw new UserInputError('A user account with this email already exists.')
+    */
+    return emailBelongsToUser || {}
   } finally {
     session.close()
   }

backend/src/schema/resolvers/registration.js

@@ -13,7 +13,12 @@ export default {
       args.nonce = generateNonce()
       args.email = normalizeEmail(args.email)
       let emailAddress = await existingEmailAddress({ args, context })
-      if (emailAddress) return emailAddress
+      /*
+      if (emailAddress.user) {
+        // what to do?
+      }
+      */
+      if (emailAddress.alreadyExistingEmail) return emailAddress.alreadyExistingEmail
       try {
         emailAddress = await neode.create('EmailAddress', args)
         return emailAddress.toJson()