feat: add in memory storage for exported scenes

package-lock.json

@@ -23,6 +23,7 @@
         "@types/jest": "^27.0.1",
         "@types/node": "^16.0.0",
         "@types/supertest": "^2.0.11",
+        "@types/type-is": "^1.6.3",
         "@typescript-eslint/eslint-plugin": "^4.28.2",
         "@typescript-eslint/parser": "^4.28.2",
         "eslint": "^7.30.0",
@@ -2150,6 +2151,15 @@
         "@types/superagent": "*"
       }
     },
+    "node_modules/@types/type-is": {
+      "version": "1.6.3",
+      "resolved": "https://registry.npmjs.org/@types/type-is/-/type-is-1.6.3.tgz",
+      "integrity": "sha512-PNs5wHaNcBgCQG5nAeeZ7OvosrEsI9O4W2jAOO9BCCg4ux9ZZvH2+0iSCOIDBiKuQsiNS8CBlmfX9f5YBQ22cA==",
+      "dev": true,
+      "dependencies": {
+        "@types/node": "*"
+      }
+    },
     "node_modules/@types/yargs": {
       "version": "16.0.4",
       "resolved": "https://registry.npmjs.org/@types/yargs/-/yargs-16.0.4.tgz",
@@ -10950,6 +10960,15 @@
         "@types/superagent": "*"
       }
     },
+    "@types/type-is": {
+      "version": "1.6.3",
+      "resolved": "https://registry.npmjs.org/@types/type-is/-/type-is-1.6.3.tgz",
+      "integrity": "sha512-PNs5wHaNcBgCQG5nAeeZ7OvosrEsI9O4W2jAOO9BCCg4ux9ZZvH2+0iSCOIDBiKuQsiNS8CBlmfX9f5YBQ22cA==",
+      "dev": true,
+      "requires": {
+        "@types/node": "*"
+      }
+    },
     "@types/yargs": {
       "version": "16.0.4",
       "resolved": "https://registry.npmjs.org/@types/yargs/-/yargs-16.0.4.tgz",

package.json

@@ -4,7 +4,7 @@
   "description": "",
   "author": "",
   "private": true,
-  "license": "UNLICENSED",
+  "license": "MIT",
   "scripts": {
     "prebuild": "rimraf dist",
     "build": "nest build",
@@ -36,6 +36,7 @@
     "@types/jest": "^27.0.1",
     "@types/node": "^16.0.0",
     "@types/supertest": "^2.0.11",
+    "@types/type-is": "^1.6.3",
     "@typescript-eslint/eslint-plugin": "^4.28.2",
     "@typescript-eslint/parser": "^4.28.2",
     "eslint": "^7.30.0",

src/app.controller.spec.ts

@@ -1,22 +0,0 @@
-import { Test, TestingModule } from '@nestjs/testing';
-import { AppController } from './app.controller';
-import { AppService } from './app.service';
-
-describe('AppController', () => {
-  let appController: AppController;
-
-  beforeEach(async () => {
-    const app: TestingModule = await Test.createTestingModule({
-      controllers: [AppController],
-      providers: [AppService],
-    }).compile();
-
-    appController = app.get<AppController>(AppController);
-  });
-
-  describe('root', () => {
-    it('should return "Hello World!"', () => {
-      expect(appController.getHello()).toBe('Hello World!');
-    });
-  });
-});

src/app.controller.ts

@@ -1,12 +0,0 @@
-import { Controller, Get } from '@nestjs/common';
-import { AppService } from './app.service';
-
-@Controller()
-export class AppController {
-  constructor(private readonly appService: AppService) {}
-
-  @Get()
-  getHello(): string {
-    return this.appService.getHello();
-  }
-}

src/app.module.ts

@@ -1,10 +1,15 @@
-import { Module } from '@nestjs/common';
-import { AppController } from './app.controller';
-import { AppService } from './app.service';
+import { MiddlewareConsumer, Module } from '@nestjs/common';
+import { RawParserMiddleware } from './raw-parser.middleware';
+import { ScenesController } from './scenes/scenes.controller';
+import { MemoryService } from './storages/memory.service';
 
 @Module({
   imports: [],
-  controllers: [AppController],
-  providers: [AppService],
+  controllers: [ScenesController],
+  providers: [MemoryService],
 })
-export class AppModule {}
+export class AppModule {
+  configure(consumer: MiddlewareConsumer) {
+    consumer.apply(RawParserMiddleware).forRoutes('**');
+  }
+}

src/app.service.ts

@@ -1,8 +0,0 @@
-import { Injectable } from '@nestjs/common';
-
-@Injectable()
-export class AppService {
-  getHello(): string {
-    return 'Hello World!';
-  }
-}

src/main.ts

@@ -2,7 +2,11 @@ import { NestFactory } from '@nestjs/core';
 import { AppModule } from './app.module';
 
 async function bootstrap() {
-  const app = await NestFactory.create(AppModule);
-  await app.listen(3000);
+  const app = await NestFactory.create(AppModule, {
+    cors: true,
+  });
+  app.setGlobalPrefix('api/v2');
+
+  await app.listen(8080);
 }
 bootstrap();

src/raw-parser.middleware.spec.ts

@@ -0,0 +1,7 @@
+import { RawParserMiddleware } from './raw-parser.middleware';
+
+describe('RawParserMiddleware', () => {
+  it('should be defined', () => {
+    expect(new RawParserMiddleware()).toBeDefined();
+  });
+});

src/raw-parser.middleware.ts

@@ -0,0 +1,14 @@
+import { Injectable, NestMiddleware } from '@nestjs/common';
+import { raw } from 'express';
+import { hasBody } from 'type-is';
+
+// Excalidraw Front end doesn't send a Content Type Header 
+// so we tell raw parser to check if there is a body
+const rawParserMiddleware = raw({ type: hasBody });
+
+@Injectable()
+export class RawParserMiddleware implements NestMiddleware {
+  use(req: any, res: any, next: () => void) {
+    rawParserMiddleware(req, res, next);
+  }
+}

src/scenes/scenes.controller.spec.ts

@@ -0,0 +1,18 @@
+import { Test, TestingModule } from '@nestjs/testing';
+import { ScenesController } from './scenes.controller';
+
+describe('ScenesController', () => {
+  let controller: ScenesController;
+
+  beforeEach(async () => {
+    const module: TestingModule = await Test.createTestingModule({
+      controllers: [ScenesController],
+    }).compile();
+
+    controller = module.get<ScenesController>(ScenesController);
+  });
+
+  it('should be defined', () => {
+    expect(controller).toBeDefined();
+  });
+});

src/scenes/scenes.controller.ts

@@ -0,0 +1,42 @@
+import {
+  Body,
+  Controller,
+  Get,
+  Header,
+  Param,
+  Post,
+  Res,
+} from '@nestjs/common';
+import { Response } from 'express';
+import { MemoryService } from 'src/storages/memory.service';
+import { hash, hexadecimalToDecimal } from 'src/utils';
+import { Readable } from 'stream';
+
+@Controller()
+export class ScenesController {
+  constructor(private storageService: MemoryService) {}
+  @Get(':id')
+  @Header('content-type', 'application/octet-stream')
+  async findOne(@Param() params, @Res() res: Response): Promise<void> {
+    const data = await this.storageService.load(params.id);
+
+    const stream = new Readable();
+    stream.push(data);
+    stream.push(null);
+    stream.pipe(res);
+  }
+
+  @Post()
+  async create(@Body() payload: Buffer) {
+
+    const drawingHash = hash(payload);
+    const id = hexadecimalToDecimal(drawingHash);
+
+    await this.storageService.save(id, payload);
+
+    return {
+      id,
+      data: `http://localhost:8080/api/v2/${id}`,
+    };
+  }
+}

src/storages/memory.service.spec.ts

@@ -0,0 +1,18 @@
+import { Test, TestingModule } from '@nestjs/testing';
+import { MemoryService } from './memory.service';
+
+describe('MemoryService', () => {
+  let service: MemoryService;
+
+  beforeEach(async () => {
+    const module: TestingModule = await Test.createTestingModule({
+      providers: [MemoryService],
+    }).compile();
+
+    service = module.get<MemoryService>(MemoryService);
+  });
+
+  it('should be defined', () => {
+    expect(service).toBeDefined();
+  });
+});

src/storages/memory.service.ts

@@ -0,0 +1,17 @@
+import { Injectable } from '@nestjs/common';
+import { StorageService } from './storageService';
+
+@Injectable()
+export class MemoryService implements StorageService {
+
+  scenesMap = new Map<string, Buffer>();
+
+  async save(id: string, data: Buffer): Promise<boolean> {
+    this.scenesMap.set(id, data);
+    return true;
+  }
+
+  async load(id: string): Promise<false | Buffer> {
+    return this.scenesMap.get(id);
+  }
+}

src/storages/storageService.ts

@@ -0,0 +1,5 @@
+export interface StorageService {
+  save(id: string, data: Buffer): Promise<boolean>;
+
+  load(id: string): Promise<Buffer | false>;
+}

src/utils.ts

@@ -0,0 +1,12 @@
+import { createHash } from 'crypto';
+
+export function hash(buffer): string {
+  return createHash(`sha256`).update(buffer).digest(`hex`);
+}
+
+// Copied from https://github.com/NMinhNguyen/excalidraw-json
+export function hexadecimalToDecimal(hexadecimal: string) {
+  // See https://stackoverflow.com/a/53751162
+  const bigInt = BigInt(`0x${hexadecimal}`);
+  return bigInt.toString(10);
+}