feature: export model endpoint (#213)

* Adds export model endpoint

This commit adds the necessary structure to export model

Resolves #75

* Adds import model endpoint

This commit adds import model endpoint for tests

Resolves #76

* Adds crypto unit test

Refs #75 #76

* Adds export model unit test

Resolves #75

.gitignore

@@ -3,6 +3,7 @@
 ###############################################################################
 .idea
 .DS_Store
+.env
 
 ###############################################################################
 # node-waf configuration
@@ -24,4 +25,5 @@ package-lock.json
 ###############################################################################
 app/css
 app/assets
-data/
+data/
+coverage/

package.json

@@ -20,6 +20,7 @@
     "bootstrap": "^3.4.1",
     "cssnano": "^4.1.10",
     "del": "^5.1.0",
+    "dotenv": "^10.0.0",
     "ejs": "^3.1.3",
     "errorhandler": "^1.5.1",
     "express": "^4.17.1",
@@ -41,6 +42,7 @@
     "mongodb": "~3.5.8",
     "mongoose": "^5.9.18",
     "morgan": "^1.10.0",
+    "raw-body": "^2.4.1",
     "response-time": "^2.3.2",
     "sweet-feedback": "^1.0.1",
     "textangular": "^1.5.16"

server_app/app.js

@@ -6,6 +6,9 @@ const session = require("express-session");
 const bodyParser = require("body-parser");
 const ejs = require("ejs");
 const path = require("path");
+const { uploadMiddleware } = require("./middleware/middleware");
+
+require("dotenv").config();
 
 let app = express();
 
@@ -17,6 +20,8 @@ app.engine("html", ejs.renderFile);
 app.use(morgan("dev"));
 app.use(bodyParser.json()); // support json encoded bodies
 app.use(bodyParser.urlencoded({ extended: true })); // support encoded bodies
+
+app.use(uploadMiddleware);
 const appPath = path.join(__dirname, "../app");
 app.use(express.static(appPath));
 app.use(express.static(`${appPath}/assets`));
@@ -35,6 +40,7 @@ app.use(errorhandler());
 const userHandler = require("./user/handler");
 const modelHandler = require("./model/handler");
 
+
 app.use("/users", userHandler);
 app.use("/models", modelHandler);
 

server_app/helpers/crypto.js

@@ -0,0 +1,34 @@
+const crypto = require("crypto");
+
+const ALGORITHM = "aes-256-ctr";
+const ENCRYPTION_KEY = process.env.SECRET_TOKEN;
+const IV_LENGTH = 16;
+
+const encrypt = (data) => {
+	const key = crypto
+		.createHash("sha256")
+		.update(String(ENCRYPTION_KEY))
+		.digest("base64")
+		.substr(0, 32);
+	const iv = crypto.randomBytes(IV_LENGTH);
+	const cipher = crypto.createCipheriv(ALGORITHM, Buffer.from(key), iv);
+	return Buffer.concat([iv, cipher.update(data), cipher.final()]);
+};
+
+const decrypt = (hash) => {
+	const key = crypto
+		.createHash("sha256")
+		.update(String(ENCRYPTION_KEY))
+		.digest("base64")
+		.substr(0, 32);
+	const iv = hash.slice(0, IV_LENGTH);
+	const decipher = crypto.createDecipheriv(ALGORITHM, Buffer.from(key), iv);
+	const data = hash.slice(IV_LENGTH);
+	const decrypted = Buffer.concat([decipher.update(data), decipher.final()]);
+	return decrypted.toString();
+};
+
+module.exports = {
+	encrypt,
+	decrypt,
+};

server_app/helpers/crypto.test.js

@@ -0,0 +1,35 @@
+const { encrypt, decrypt } = require("./crypto");
+
+describe("crypto test", () => {
+	const OLD_ENV = process.env;
+
+	beforeEach(() => {
+		jest.resetModules();
+		process.env = { ...OLD_ENV };
+	});
+
+	afterAll(() => {
+		process.env = OLD_ENV;
+	});
+
+	test("Encrypt data", async () => {
+		process.env.SECRET_TOKEN = "some_token";
+		const data = { name: "some_name" };
+		const json = JSON.stringify(data);
+
+		const encrypted = encrypt(json);
+
+		expect(encrypted).not.toBeNull();
+	});
+
+	test("Decrypt data", async () => {
+		process.env.SECRET_TOKEN = "some_token";
+		const data = { name: "some_name" };
+		const json = JSON.stringify(data);
+
+		const decrypted = decrypt(encrypt(json));
+
+		expect(decrypted).not.toBeNull();
+		expect(JSON.parse(decrypted)).toEqual(data);
+	});
+});

server_app/middleware/middleware.js

@@ -0,0 +1,22 @@
+const getRawBody = require("raw-body");
+
+const uploadMiddleware = (req, res, next) => {
+	if (req.headers["content-type"] === "application/octet-stream") {
+		const options = {
+			length: req.headers["content-length"],
+			encoding: req.charset,
+		};
+		const callback = (err, string) => {
+			if (err) return next(err);
+			req.body = string;
+			return next();
+		};
+		getRawBody(req, options, callback);
+	} else {
+		next();
+	}
+};
+
+module.exports = {
+	uploadMiddleware,
+};

server_app/model/handler.js

@@ -2,6 +2,7 @@ const express = require("express");
 const bodyParser = require("body-parser");
 const modelService = require("./service");
 const modelValidator = require("./validator");
+const { decrypt } = require("../helpers/crypto");
 
 const router = express.Router();
 router.use(bodyParser.json());
@@ -34,9 +35,9 @@ const save = async (req, res) => {
 	try {
 		const name = req.body.name;
 		const type = req.body.type;
-		const userId = req.body.user; 
+		const userId = req.body.user;
 		const model = req.body.model;
-		
+
 		const validation = modelValidator.validateSaveParams({
 			name,
 			type,
@@ -100,10 +101,41 @@ const rename = async (req, res) => {
 	}
 };
 
+const exportModel = async (req, res) => {
+	try {
+		const { modelId } = req.params;
+		const { name, data } = await modelService.exportModel(modelId);
+		res.writeHead(200, {
+			"Content-Type": "application/octet-stream",
+			"Content-Disposition": `attachment; filename=${name}.brm`,
+			"Content-Length": data.length,
+		});
+		return res.end(data);
+	} catch (error) {
+		console.error(error);
+		return res
+			.status(500)
+			.send("There's an error while treating export your model request");
+	}
+};
+
+const importModel = async (req, res) => {
+	try {
+		return res.status(200).json(JSON.parse(decrypt(req.body)));
+	} catch (error) {
+		console.error(error);
+		return res
+			.status(500)
+			.send("There's an error while treating import your model request");
+	}
+};
+
 module.exports = router
 	.get("/", listAll)
 	.post("/", save)
 	.get("/:modelId", getById)
 	.put("/:modelId", edit)
 	.delete("/:modelId", remove)
-	.put("/:modelId/rename", rename);
+	.put("/:modelId/rename", rename)
+	.get("/:modelId/export", exportModel)
+	.post("/import", importModel);

server_app/model/handler.test.js

@@ -1,7 +1,9 @@
 const request = require("supertest");
 const app = require("../app");
+
 jest.mock("./service");
 const mockModelService = require("./service");
+const { encrypt } = require("../helpers/crypto");
 
 afterEach(() => {
 	jest.restoreAllMocks();
@@ -41,9 +43,68 @@ describe("Test save /models", () => {
 
 describe("Test list all /models", () => {
 	test("It should send 200 user exists", async () => {
+		const response = await request(app).get("/").send([]);
+		expect(response.statusCode).toBe(200);
+	});
+});
+
+describe("Test export /models", () => {
+	const OLD_ENV = process.env;
+
+	beforeEach(() => {
+		jest.resetModules();
+		process.env = { ...OLD_ENV };
+	});
+
+	afterAll(() => {
+		process.env = OLD_ENV;
+	});
+
+	const model = {
+		_id: "6179eacfc9cac3976aef0fec",
+		who: "6179eac1c9cac3976aef0fe8",
+		type: "conceptual",
+		model:
+			'{"cells":[{"type":"erd.Entity","supertype":"Entity","isExtended":false,"autorelationship":false,"size":{"width":80,"height":40},"position":{"x":280,"y":120},"angle":0,"id":"9a6cc538-d1bd-4e39-8c38-a85078814dc9","z":1,"attrs":{".outer":{"fill":"#FFFFFF","stroke":"black"},"text":{"text":"Entidade"}}},{"type":"erd.Relationship","supertype":"Relationship","autorelationship":false,"size":{"width":85,"height":45},"position":{"x":560,"y":120},"angle":0,"id":"f5a1e4c3-a6a2-49f1-9e92-7b7210695d5a","z":2,"attrs":{".outer":{"fill":"#FFFFFF","stroke":"black"},"text":{"text":"Rel"}}},{"type":"erd.BlockAssociative","supertype":"Entity","size":{"width":100,"height":50},"position":{"x":780,"y":120},"angle":0,"id":"18f3b6fc-83de-4ad0-9dc4-e07569598374","z":3,"embeds":["1d11c65e-89d4-47f2-b991-dd0068833d77"],"attrs":{".outer":{"fill":"transparent","stroke":"black"}}},{"type":"erd.Relationship","supertype":"Relationship","autorelationship":false,"size":{"width":85,"height":45},"position":{"x":786,"y":122},"angle":0,"id":"1d11c65e-89d4-47f2-b991-dd0068833d77","z":4,"parent":"18f3b6fc-83de-4ad0-9dc4-e07569598374","attrs":{".outer":{"fill":"#FFFFFF","stroke":"black"},"text":{"text":"Rel"}}},{"type":"link","source":{"id":"f5a1e4c3-a6a2-49f1-9e92-7b7210695d5a"},"target":{"id":"18f3b6fc-83de-4ad0-9dc4-e07569598374"},"id":"b99e4aef-2826-4df3-b4fd-17bcb81f5fa5","z":5,"labels":[{"position":0.7,"attrs":{"text":{"text":"(0, n)"}}}],"attrs":{}},{"type":"link","source":{"id":"f5a1e4c3-a6a2-49f1-9e92-7b7210695d5a"},"target":{"id":"9a6cc538-d1bd-4e39-8c38-a85078814dc9"},"id":"7c54152c-b6f1-4423-9543-3c57c6087036","z":6,"labels":[{"position":0.7,"attrs":{"text":{"text":"(0, n)"}}}],"attrs":{}}]}',
+		name: "modeloteste",
+		created: "2021-10-28T00:11:59.121Z",
+		__v: 0,
+	};
+
+	test("It should send 200 when model is exported", async () => {
+		process.env.SECRET_TOKEN = "some_token";
+		mockModelService.exportModel.mockReturnValue({
+			name: "modeloteste",
+			data: encrypt(JSON.stringify(model)),
+		});
+
 		const response = await request(app)
-			.get("/")
-			.send([]);
+			.get("/models/6179eacfc9cac3976aef0fec/export")
+			.send(encrypt(JSON.stringify(model)));
+
+		expect(response.header).toHaveProperty("content-type");
+		expect(response.header).toHaveProperty("content-disposition");
+		expect(response.header).toHaveProperty("content-length");
+		expect(response.header["content-type"]).toEqual("application/octet-stream");
+		expect(response.header["content-disposition"]).toEqual(
+			"attachment; filename=modeloteste.brm"
+		);
+		expect(response.header["content-length"]).toEqual("2137");
 		expect(response.statusCode).toBe(200);
+		expect(mockModelService.exportModel).toHaveBeenCalled();
+	});
+
+	test("It should send 500 when model is not exported", async () => {
+		process.env.SECRET_TOKEN = "some_token";
+		mockModelService.exportModel.mockImplementation(() => {
+			throw new Error();
+		});
+
+		const response = await request(app)
+			.get("/models/6179eacfc9cac3976aef0fec/export")
+			.send(encrypt(JSON.stringify(model)));
+
+		expect(response.statusCode).toBe(500);
+		expect(mockModelService.exportModel).toHaveBeenCalled();
 	});
 });

server_app/model/service.js

@@ -1,4 +1,5 @@
 const modelRepository = require("./model");
+const { encrypt } = require("../helpers/crypto");
 
 const listAll = async (userId) => {
 	return new Promise(async (resolve, reject) => {
@@ -95,13 +96,29 @@ const remove = async (modelId) => {
 	});
 };
 
+const exportModel = async (modelId) => {
+	return new Promise(async (resolve, reject) => {
+		try {
+			const model = await getById(modelId);
+			return resolve({
+				name: model.name.replace(/[^a-zA-Z0-9]/g, ""),
+				data: encrypt(JSON.stringify(model)),
+			});
+		} catch (error) {
+			console.error(error);
+			return reject(error);
+		}
+	});
+};
+
 const modelService = {
 	listAll,
 	getById,
 	save,
 	edit,
 	remove,
 	rename,
+	exportModel,
 };
 
 module.exports = modelService;