refactor: add DI container and refactor student repository

README.md

@@ -8,7 +8,7 @@ This project is structured as a monorepo and based on [Domain Driven Design (DDD
 
 ```
 ├── packages
-│   ├── core                        - Contains all of your business logic following clean architecture and domain driven design/
+│   ├── core                        - Contains all of your business logic following clean architecture and domain driven design
 │   │   └── src
 │   │       ├── application         - Define behaviour of the application, interact with services from outside packages/core
 │   │       │   ├── ports           - Define contracts interfaces that should be honoured by the infrastructure.
@@ -30,19 +30,19 @@ This project is structured as a monorepo and based on [Domain Driven Design (DDD
 ### 📜 Presiquites
 
 - [Node.js](https://nodejs.org/en/) (v18 or higher)
-- [npm](https://www.npmjs.com/) (v8 or higher)
+- [pnpm](https://pnpm.io/) (v8 or higher)
 - [AWS CLI](https://aws.amazon.com/cli/) (v2 or higher)
 
 ### 📦 Installation
 
 ```bash
-$ npm i
+$ pnpm i
 ```
 
 ### 🏃‍♂️ Run
 
 ```bash
-$ npm run dev
+$ pnpm dev
 ```
 
 ### 🚀 Deploy
@@ -55,7 +55,7 @@ $ npm run dev
 #### Deploy
 
 ```bash
-$ npm run deploy --stage [stage_name]
+$ pnpm deploy --stage [stage_name]
 ```
 
 ## 📝 License

packages/core/src/application/index.ts

@@ -1,2 +1,4 @@
+import 'reflect-metadata';
+
 export * from './prisma';
 export * from './util';

packages/core/src/application/ports/index.ts

@@ -1 +1,3 @@
 export * from './subject';
+export * from './student';
+export * from './shared';

packages/core/src/application/ports/score/index.ts

@@ -0,0 +1 @@
+export * from './interfaces';

packages/core/src/application/ports/score/interfaces.ts

@@ -0,0 +1,8 @@
+import { Score } from '@prisma/client';
+import { LearningResult } from '../subject';
+import { GetById } from '@infra/student';
+
+export interface ICalculateScoreService {
+  getLearningResult(scores: Score[]): LearningResult;
+  getAverageScore(student: GetById): number;
+}

packages/core/src/application/ports/shared/index.ts

@@ -0,0 +1 @@
+export * from './interfaces';

packages/core/src/application/ports/shared/interfaces.ts

@@ -0,0 +1 @@
+export interface ExpandFields {}

packages/core/src/application/ports/student/index.ts

@@ -0,0 +1 @@
+export * from './interfaces';

packages/core/src/application/ports/student/interfaces.ts

@@ -0,0 +1,13 @@
+import { StudentQueryResult } from '@infra/index';
+import { ExpandFields } from '../shared';
+
+export interface StudentExpandFields extends ExpandFields {
+  withScores?: boolean;
+}
+
+export interface IStudentRepository {
+  getById(
+    id: string,
+    expandFields?: StudentExpandFields,
+  ): Promise<StudentQueryResult>;
+}

packages/core/src/container/container.ts

@@ -0,0 +1,12 @@
+import Container from 'typedi';
+import { Cradle } from './cradle';
+import { CalculateScoreService } from '@infra/score';
+import { StudentRepository } from '@infra/student';
+
+export const container: Cradle = {
+  // Services
+  calculateScoreService: Container.get(CalculateScoreService),
+
+  // Repositories
+  studentRepository: Container.get(StudentRepository),
+};

packages/core/src/container/cradle.ts

@@ -0,0 +1,9 @@
+import { CalculateScoreService } from '@infra/score';
+import { StudentRepository } from '@infra/student';
+
+export interface Cradle {
+  // Services
+  calculateScoreService: CalculateScoreService;
+  // Repositories
+  studentRepository: StudentRepository;
+}

packages/core/src/container/index.ts

@@ -0,0 +1,2 @@
+export * from './container';
+export * from './cradle';

packages/core/src/index.ts

@@ -1,3 +1,7 @@
+import 'reflect-metadata';
+
 export * from './application';
 export * from './domain';
 export * from './infra';
+export * from './shared';
+export * from './container';

packages/core/src/infra/score/calculateScoreService.ts

@@ -1,54 +1,56 @@
 import { LearningResult } from '@application/ports';
 import { isPassedSubject, shouldCalculateScore } from '@application/util';
 import { AlphabetToTetraScore } from '@domain/index';
-import { StudentWithScoresAndSubjects } from '@infra/index';
+import { StudentQueryResult } from '@infra/index';
 import { Score } from '@prisma/client';
+import { Service } from 'typedi';
+
+@Service()
+export class CalculateScoreService {
+  getLearningResult(scores: Score[]): LearningResult {
+    const passed = scores.filter((score) => isPassedSubject(score)).length;
+    const failed = scores.length - passed;
+
+    return {
+      passed,
+      failed,
+    };
+  }
+
+  getAverageScore(student?: StudentQueryResult): number {
+    if (!student) throw new Error('Student not found');
+
+    const { scores } = student;
+
+    const totalAverageScore = scores.reduce((acc, score) => {
+      if (shouldCalculateScore(score)) {
+        if (
+          !score.alphabetScore ||
+          !(score.alphabetScore in AlphabetToTetraScore)
+        ) {
+          return acc;
+        }
+
+        return (
+          acc +
+          // * This is an enum so it's safe to ignore this
+          // eslint-disable-next-line @typescript-eslint/ban-ts-comment
+          // @ts-ignore
+          AlphabetToTetraScore[score.alphabetScore] *
+            score.subject.numberOfCredits
+        );
+      }
+      return acc;
+    }, 0);
 
-export const getLearningResult = (scores: Score[]): LearningResult => {
-  const passed = scores.filter((score) => isPassedSubject(score)).length;
-  const failed = scores.length - passed;
-
-  return {
-    passed,
-    failed,
-  };
-};
-
-export const getAverageScore = (
-  student?: StudentWithScoresAndSubjects,
-): number => {
-  if (!student) throw new Error('Student not found');
-
-  const { scores } = student;
-
-  const totalAverageScore = scores.reduce((acc, score) => {
-    if (shouldCalculateScore(score)) {
-      if (
-        !score.alphabetScore ||
-        !(score.alphabetScore in AlphabetToTetraScore)
-      ) {
-        return acc;
+    const totalCredits = scores.reduce((acc, score) => {
+      if (shouldCalculateScore(score)) {
+        return acc + score.subject.numberOfCredits;
       }
+      return acc;
+    }, 0);
 
-      return (
-        acc +
-        // * This is an enum so it's safe to ignore this
-        // eslint-disable-next-line @typescript-eslint/ban-ts-comment
-        // @ts-ignore
-        AlphabetToTetraScore[score.alphabetScore] *
-          score.subject.numberOfCredits
-      );
-    }
-    return acc;
-  }, 0);
-
-  const totalCredits = scores.reduce((acc, score) => {
-    if (shouldCalculateScore(score)) {
-      return acc + score.subject.numberOfCredits;
-    }
-    return acc;
-  }, 0);
-
-  const averageScore = totalAverageScore / totalCredits;
-  return Number(averageScore.toFixed(2));
-};
+    const averageScore = totalAverageScore / totalCredits;
+    return Number(averageScore.toFixed(2));
+  }
+}

packages/core/src/infra/student/include.ts

@@ -0,0 +1,12 @@
+import { Prisma } from '@prisma/client';
+
+export const studentIncludeScoreAndSubject =
+  Prisma.validator<Prisma.StudentDefaultArgs>()({
+    include: {
+      scores: {
+        include: {
+          subject: true,
+        },
+      },
+    },
+  });

packages/core/src/infra/student/index.ts

@@ -1,2 +1,2 @@
-export * from './studentPersistence';
+export * from './studentRepository';
 export * from './types';

packages/core/src/infra/student/studentRepository.ts

@@ -0,0 +1,33 @@
+import { prisma } from '@application/index';
+import { IStudentRepository, StudentExpandFields } from '@application/ports';
+import { Prisma } from '@prisma/client';
+import { Repository } from 'shared';
+import { StudentQueryResult } from './types';
+
+@Repository()
+export class StudentRepository implements IStudentRepository {
+  async getById(id: string, expandFields: StudentExpandFields) {
+    // TODO: Implement a better solution for dynamic include
+    const include: Prisma.StudentInclude = {
+      scores: expandFields.withScores
+        ? {
+            include: {
+              subject: true,
+            },
+            where: {
+              studentId: id,
+            },
+          }
+        : {},
+    };
+
+    const student = await prisma.student.findUnique({
+      include,
+      where: {
+        id: id,
+      },
+    });
+
+    return student as unknown as StudentQueryResult;
+  }
+}

packages/core/src/infra/student/types.ts

@@ -1,6 +1,12 @@
 import { Prisma } from '@prisma/client';
-import { getStudentWithScoreById } from '@infra/student';
+import { studentIncludeScoreAndSubject } from './include';
 
-export type StudentWithScoresAndSubjects = Prisma.PromiseReturnType<
-  typeof getStudentWithScoreById
+/**
+ * * This is a type that is used to dynamically include the fields of the student
+ * * This will resolve type error when we use the `include` option of Prisma dynamically
+ * TODO: Remove this when Prisma support dynamic include types or when we have better solution
+ * https://github.com/prisma/prisma/issues/20816#issuecomment-1873546485
+ */
+export type StudentQueryResult = Prisma.StudentGetPayload<
+  typeof studentIncludeScoreAndSubject
 >;

packages/core/src/shared/decorators/index.ts

@@ -0,0 +1 @@
+export * from './repository';

packages/core/src/shared/decorators/repository.ts

@@ -0,0 +1,9 @@
+import { ClassConstructor } from 'shared/types';
+import { Service } from 'typedi';
+
+export function Repository<T>() {
+  return function (target: ClassConstructor<T>) {
+    // Apply the TypeDI Service decorator
+    Service()(target);
+  };
+}

packages/core/src/shared/index.ts

@@ -0,0 +1,2 @@
+export * from './decorators';
+export * from './types';

packages/core/src/shared/types/index.ts

@@ -0,0 +1,2 @@
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+export type ClassConstructor<T> = new (...args: any[]) => T;

packages/core/tsconfig.json

@@ -2,6 +2,8 @@
 	"extends": "@tsconfig/node18/tsconfig.json",
 	"compilerOptions": {
 		"module": "esnext",
+		"emitDecoratorMetadata": true,
+		"experimentalDecorators": true,
 		"moduleResolution": "node",
 		"baseUrl": "src",
 		"paths": {

packages/functions/package.json

@@ -16,6 +16,8 @@
     "@middy/core": "^4.5.5",
     "@middy/http-error-handler": "^4.5.5",
     "@middy/http-json-body-parser": "^4.5.5",
-    "@middy/validator": "^4.5.5"
+    "@middy/validator": "^4.5.5",
+    "reflect-metadata": "^0.2.1",
+    "typedi": "^0.10.0"
   }
 }