Removed commented code, implemented Singleton.

backend/src/apis/KlicktippController.ts

@@ -1,4 +1,3 @@
-/* eslint-disable @typescript-eslint/restrict-template-expressions */
 /* eslint-disable @typescript-eslint/no-unsafe-member-access */
 /* eslint-disable @typescript-eslint/no-unsafe-call */
 /* eslint-disable @typescript-eslint/no-unsafe-return */
@@ -43,10 +42,9 @@ export const getKlickTippUser = async (email: string): Promise<any> => {
   const isLogin = await loginKlicktippUser()
   if (isLogin) {
     try {
-      const subscriberId = await klicktippConnector.subscriberSearch(email)
-      return klicktippConnector.subscriberGet(subscriberId)
+      return klicktippConnector.subscriberGet(await klicktippConnector.subscriberSearch(email))
     } catch (e) {
-      logger.error(`Could not find subscriber ${email}`)
+      logger.error('Could not find subscriber', email)
       return false
     }
   }
@@ -68,17 +66,16 @@ export const addFieldsToSubscriber = async (
   const isLogin = await loginKlicktippUser()
   if (isLogin) {
     try {
-      const subscriberId = await klicktippConnector.subscriberSearch(email)
+      logger.info(`Update of subscriber (${email}) has been successful`)
       const result = await klicktippConnector.subscriberUpdate(
-        subscriberId,
+        await klicktippConnector.subscriberSearch(email),
         fields,
         newemail,
         newsmsnumber,
       )
-      logger.info(`Update of subscriber (${email}) has been successful, ${result}`)
       return result
     } catch (e) {
-      logger.error(`Could not update subscriber ${email}, ${JSON.stringify(fields)}, ${e}`)
+      logger.error('Could not update subscriber', email, JSON.stringify(fields), e)
       return false
     }
   }

backend/src/server/createServer.ts

@@ -1,14 +1,14 @@
 /* eslint-disable @typescript-eslint/no-unsafe-assignment */
 /* eslint-disable @typescript-eslint/restrict-template-expressions */
 /* eslint-disable @typescript-eslint/unbound-method */
-import { Connection } from '@dbTools/typeorm'
+import { Connection as DbConnection } from '@dbTools/typeorm'
 import { ApolloServer } from 'apollo-server-express'
 import express, { Express, json, urlencoded } from 'express'
 import { Logger } from 'log4js'
 
 import { CONFIG } from '@/config'
 import { schema } from '@/graphql/schema'
-import { getConnection } from '@/typeorm/connection'
+import { Connection } from '@/typeorm/connection'
 import { checkDBVersion } from '@/typeorm/DBVersion'
 import { elopageWebhook } from '@/webhook/elopage'
 
@@ -24,7 +24,7 @@ import { plugins } from './plugins'
 interface ServerDef {
   apollo: ApolloServer
   app: Express
-  con: Connection
+  con: DbConnection
 }
 
 export const createServer = async (
@@ -37,7 +37,7 @@ export const createServer = async (
   logger.debug('createServer...')
 
   // open mysql connection
-  const con = await getConnection()
+  const con = await Connection.getInstance()
   if (!con?.isConnected) {
     logger.fatal(`Couldn't open connection to database!`)
     throw new Error(`Fatal: Couldn't open connection to database`)

backend/src/typeorm/connection.ts

@@ -1,41 +1,55 @@
 // TODO This is super weird - since the entities are defined in another project they have their own globals.
 //      We cannot use our connection here, but must use the external typeorm installation
-import { Connection, createConnection, FileLogger } from '@dbTools/typeorm'
+import { Connection as DbConnection, createConnection, FileLogger } from '@dbTools/typeorm'
 import { entities } from '@entity/index'
 
 import { CONFIG } from '@/config'
 
-let connection: Connection | null
+// eslint-disable-next-line @typescript-eslint/no-extraneous-class
+export class Connection {
+  private static instance: DbConnection
 
-export const getConnection = async (): Promise<Connection | null> => {
-  if (connection) return connection
-  connection = await createMyConnection()
-  return connection
-}
+  /**
+   * The Singleton's constructor should always be private to prevent direct
+   * construction calls with the `new` operator.
+   */
+  // eslint-disable-next-line no-useless-constructor, @typescript-eslint/no-empty-function
+  private constructor() {}
 
-const createMyConnection = async (): Promise<Connection | null> => {
-  try {
-    return createConnection({
-      name: 'default',
-      type: 'mysql',
-      host: CONFIG.DB_HOST,
-      port: CONFIG.DB_PORT,
-      username: CONFIG.DB_USER,
-      password: CONFIG.DB_PASSWORD,
-      database: CONFIG.DB_DATABASE,
-      entities,
-      synchronize: false,
-      logging: true,
-      logger: new FileLogger('all', {
-        logPath: CONFIG.TYPEORM_LOGGING_RELATIVE_PATH,
-      }),
-      extra: {
-        charset: 'utf8mb4_unicode_ci',
-      },
-    })
-  } catch (error) {
-    // eslint-disable-next-line no-console
-    console.log(error)
-    return null
+  /**
+   * The static method that controls the access to the singleton instance.
+   *
+   * This implementation let you subclass the Singleton class while keeping
+   * just one instance of each subclass around.
+   */
+  public static async getInstance(): Promise<DbConnection | null> {
+    if (Connection.instance) {
+      return Connection.instance
+    }
+    try {
+      Connection.instance = await createConnection({
+        name: 'default',
+        type: 'mysql',
+        host: CONFIG.DB_HOST,
+        port: CONFIG.DB_PORT,
+        username: CONFIG.DB_USER,
+        password: CONFIG.DB_PASSWORD,
+        database: CONFIG.DB_DATABASE,
+        entities,
+        synchronize: false,
+        logging: true,
+        logger: new FileLogger('all', {
+          logPath: CONFIG.TYPEORM_LOGGING_RELATIVE_PATH,
+        }),
+        extra: {
+          charset: 'utf8mb4_unicode_ci',
+        },
+      })
+      return Connection.instance
+    } catch (error) {
+      // eslint-disable-next-line no-console
+      console.log(error)
+      return null
+    }
   }
 }

backend/src/util/executeKlicktipp.ts

@@ -1,9 +1,9 @@
-import { getConnection } from '@/typeorm/connection'
+import { Connection } from '@/typeorm/connection'
 
 import { exportEventDataToKlickTipp } from './klicktipp'
 
 async function executeKlicktipp(): Promise<boolean> {
-  const connection = await getConnection()
+  const connection = await Connection.getInstance()
   if (connection) {
     await exportEventDataToKlickTipp()
     await connection.close()

backend/src/util/klicktipp.test.ts

@@ -50,7 +50,6 @@ describe('klicktipp', () => {
       mutation: login,
       variables: { email: 'bibi@bloxberg.de', password: 'Aa12345_' },
     })
-    // await con.close()
   })
 
   afterAll(() => {
@@ -59,8 +58,6 @@ describe('klicktipp', () => {
 
   describe('exportEventDataToKlickTipp', () => {
     it('calls the KlicktippController', async () => {
-      // console.log(await lastDateTimeEvents('USER_LOGIN'))
-      // console.log(con)
       await exportEventDataToKlickTipp()
       expect(addFieldsToSubscriber).toBeCalled()
     })

backend/src/util/klicktipp.ts

@@ -24,11 +24,11 @@ export async function retrieveNotRegisteredEmails(): Promise<string[]> {
 
 async function klickTippSendFieldToUser(
   events: { email: string; value: Date }[],
-  value: string,
+  field: string,
 ): Promise<void> {
   for (const event of events) {
     const time = event.value.setSeconds(0)
-    await addFieldsToSubscriber(event.email, { [value]: Math.trunc(time / 1000) })
+    await addFieldsToSubscriber(event.email, { [field]: Math.trunc(time / 1000) })
   }
 }
 
@@ -53,6 +53,3 @@ export async function exportEventDataToKlickTipp(): Promise<boolean> {
 
   return true
 }
-
-// void exportEventDataToKlickTipp()
-// void retrieveNotRegisteredEmails()