From 2ce14d1a89ca4337e6eddb00fa00272eab94e758 Mon Sep 17 00:00:00 2001
From: Moriz Wahl <moriz.wahl@gmx.de>
Date: Tue, 16 May 2023 16:38:59 +0200
Subject: [PATCH] refactor connection logic

---
 backend/src/server/createServer.ts |  4 ++--
 backend/src/typeorm/connection.ts  | 10 +++++++++-
 backend/src/util/klicktipp.ts      |  6 +++---
 3 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/backend/src/server/createServer.ts b/backend/src/server/createServer.ts
index d813c541e..ddc255268 100644
--- a/backend/src/server/createServer.ts
+++ b/backend/src/server/createServer.ts
@@ -8,7 +8,7 @@ import { Logger } from 'log4js'
 
 import { CONFIG } from '@/config'
 import { schema } from '@/graphql/schema'
-import { connection } from '@/typeorm/connection'
+import { getConnection } from '@/typeorm/connection'
 import { checkDBVersion } from '@/typeorm/DBVersion'
 import { elopageWebhook } from '@/webhook/elopage'
 
@@ -37,7 +37,7 @@ export const createServer = async (
   logger.debug('createServer...')
 
   // open mysql connection
-  const con = await connection()
+  const con = await getConnection()
   if (!con?.isConnected) {
     logger.fatal(`Couldn't open connection to database!`)
     throw new Error(`Fatal: Couldn't open connection to database`)
diff --git a/backend/src/typeorm/connection.ts b/backend/src/typeorm/connection.ts
index 7dec820b5..bd314fd3c 100644
--- a/backend/src/typeorm/connection.ts
+++ b/backend/src/typeorm/connection.ts
@@ -5,7 +5,15 @@ import { entities } from '@entity/index'
 
 import { CONFIG } from '@/config'
 
-export const connection = async (): Promise<Connection | null> => {
+let connection: Connection | null
+
+export const getConnection = async (): Promise<Connection | null> => {
+  if (connection) return connection
+  connection = await createMyConnection()
+  return connection
+}
+
+const createMyConnection = async (): Promise<Connection | null> => {
   try {
     return createConnection({
       name: 'default',
diff --git a/backend/src/util/klicktipp.ts b/backend/src/util/klicktipp.ts
index f6c631205..a315d73e6 100644
--- a/backend/src/util/klicktipp.ts
+++ b/backend/src/util/klicktipp.ts
@@ -5,10 +5,10 @@ import { getKlickTippUser, addFieldsToSubscriber } from '@/apis/KlicktippControl
 import { EventType } from '@/event/EventType'
 import { lastDateTimeEvents } from '@/graphql/resolver/util/eventList'
 import { LogError } from '@/server/LogError'
-import { connection } from '@/typeorm/connection'
+import { getConnection } from '@/typeorm/connection'
 
 export async function retrieveNotRegisteredEmails(): Promise<string[]> {
-  const con = await connection()
+  const con = await getConnection()
   if (!con) {
     throw new LogError('No connection to database')
   }
@@ -40,7 +40,7 @@ async function klickTippSendFieldToUser(
 }
 
 export async function exportEventDataToKlickTipp(): Promise<void> {
-  const connectionInstance = await connection()
+  const connectionInstance = await getConnection()
   if (!connectionInstance) {
     throw new LogError('No connection to database')
   }