refactor: better types

src/transaction/transaction.controller.ts

@@ -14,6 +14,8 @@ import {
 } from './transaction.dto';
 import { Transaction } from './transaction.entity';
 
+type TransactionRuleData = Pick<Transaction, 'amount' | 'client_id'>;
+
 @Controller('transaction')
 export class TransactionController {
   constructor(
@@ -39,9 +41,7 @@ export class TransactionController {
     });
   }
 
-  getClientDeposit = async (
+  getClientDeposit = async (transactionInput: TransactionRuleData) => {
-    transactionInput: Pick<Transaction, 'client_id'>,
-  ) => {
     try {
       const deposit =
         await this.transactionService.findByClientIdWithinActualMonth(
@@ -64,7 +64,7 @@ export class TransactionController {
     return 0;
   };
 
-  turnoverRule = async (transactionInput: Pick<Transaction, 'client_id'>) => {
+  turnoverRule = async (transactionInput: TransactionRuleData) => {
     try {
       const clientDeposit = await this.getClientDeposit(transactionInput);
       if (clientDeposit) {
@@ -75,13 +75,13 @@ export class TransactionController {
     }
   };
 
-  discountRule(transactionInput: Pick<Transaction, 'client_id'>) {
+  discountRule(transactionInput: TransactionRuleData) {
     return transactionInput.client_id === 42
       ? DiscountRuleForClientById.client_42
       : false;
   }
 
-  defaultRule(transactionInput: Pick<Transaction, 'amount'>) {
+  defaultRule(transactionInput: TransactionRuleData) {
     const commissionAmount =
       (transactionInput.amount * DefaultCommissionPercentage.percentage) / 100;
     return commissionAmount < DefaultCommissionAmount.amount
@@ -91,9 +91,9 @@ export class TransactionController {
 
   async applyRules(
     rules: ((
-      transactionInput: Pick<Transaction, 'client_id' | 'amount'>,
+      transactionInput: TransactionRuleData,
-    ) => any)[],
+    ) => number | false | undefined | Promise<number | false | undefined>)[],
-    transactionInput: Pick<Transaction, 'client_id' | 'amount'>,
+    transactionInput: TransactionRuleData,
   ) {
     let commissionAmount;
     for (let i = 0; i < rules.length; i++) {