first commit

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\ No newline at end of file

app/Dockerfile

+# syntax=docker/dockerfile:1
+FROM node:18-alpine
+WORKDIR /app
+COPY . .
+RUN yarn install --production
+CMD ["node", "src/index.js"]
+EXPOSE 3000
\ No newline at end of file

app/package.json

+{
+  "name": "101-app",
+  "version": "1.0.0",
+  "main": "index.js",
+  "license": "MIT",
+  "scripts": {
+    "prettify": "prettier -l --write \"**/*.js\"",
+    "test": "jest",
+    "dev": "nodemon src/index.js"
+  },
+  "dependencies": {
+    "express": "^4.18.2",
+    "mysql2": "^2.3.3",
+    "sqlite3": "^5.1.2",
+    "uuid": "^9.0.0",
+    "wait-port": "^1.0.4"
+  },
+  "resolutions": {
+    "ansi-regex": "5.0.1"
+  },
+  "prettier": {
+    "trailingComma": "all",
+    "tabWidth": 4,
+    "useTabs": false,
+    "semi": true,
+    "singleQuote": true
+  },
+  "devDependencies": {
+    "jest": "^29.3.1",
+    "nodemon": "^2.0.20",
+    "prettier": "^2.7.1"
+  }
+}

app/spec/persistence/sqlite.spec.js

+const db = require('../../src/persistence/sqlite');
+const fs = require('fs');
+const location = process.env.SQLITE_DB_LOCATION || '/etc/todos/todo.db';
+
+const ITEM = {
+    id: '7aef3d7c-d301-4846-8358-2a91ec9d6be3',
+    name: 'Test',
+    completed: false,
+};
+
+beforeEach(() => {
+    if (fs.existsSync(location)) {
+        fs.unlinkSync(location);
+    }
+});
+
+test('it initializes correctly', async () => {
+    await db.init();
+});
+
+test('it can store and retrieve items', async () => {
+    await db.init();
+
+    await db.storeItem(ITEM);
+
+    const items = await db.getItems();
+    expect(items.length).toBe(1);
+    expect(items[0]).toEqual(ITEM);
+});
+
+test('it can update an existing item', async () => {
+    await db.init();
+
+    const initialItems = await db.getItems();
+    expect(initialItems.length).toBe(0);
+
+    await db.storeItem(ITEM);
+
+    await db.updateItem(
+        ITEM.id,
+        Object.assign({}, ITEM, { completed: !ITEM.completed }),
+    );
+
+    const items = await db.getItems();
+    expect(items.length).toBe(1);
+    expect(items[0].completed).toBe(!ITEM.completed);
+});
+
+test('it can remove an existing item', async () => {
+    await db.init();
+    await db.storeItem(ITEM);
+
+    await db.removeItem(ITEM.id);
+
+    const items = await db.getItems();
+    expect(items.length).toBe(0);
+});
+
+test('it can get a single item', async () => {
+    await db.init();
+    await db.storeItem(ITEM);
+
+    const item = await db.getItem(ITEM.id);
+    expect(item).toEqual(ITEM);
+});

app/spec/routes/addItem.spec.js

+const db = require('../../src/persistence');
+const addItem = require('../../src/routes/addItem');
+const ITEM = { id: 12345 };
+const {v4 : uuid} = require('uuid');
+
+jest.mock('uuid', () => ({ v4: jest.fn() }));
+
+jest.mock('../../src/persistence', () => ({
+    removeItem: jest.fn(),
+    storeItem: jest.fn(),
+    getItem: jest.fn(),
+}));
+
+test('it stores item correctly', async () => {
+    const id = 'something-not-a-uuid';
+    const name = 'A sample item';
+    const req = { body: { name } };
+    const res = { send: jest.fn() };
+
+    uuid.mockReturnValue(id);
+
+    await addItem(req, res);
+
+    const expectedItem = { id, name, completed: false };
+
+    expect(db.storeItem.mock.calls.length).toBe(1);
+    expect(db.storeItem.mock.calls[0][0]).toEqual(expectedItem);
+    expect(res.send.mock.calls[0].length).toBe(1);
+    expect(res.send.mock.calls[0][0]).toEqual(expectedItem);
+});

app/spec/routes/deleteItem.spec.js

+const db = require('../../src/persistence');
+const deleteItem = require('../../src/routes/deleteItem');
+const ITEM = { id: 12345 };
+
+jest.mock('../../src/persistence', () => ({
+    removeItem: jest.fn(),
+    getItem: jest.fn(),
+}));
+
+test('it removes item correctly', async () => {
+    const req = { params: { id: 12345 } };
+    const res = { sendStatus: jest.fn() };
+
+    await deleteItem(req, res);
+
+    expect(db.removeItem.mock.calls.length).toBe(1);
+    expect(db.removeItem.mock.calls[0][0]).toBe(req.params.id);
+    expect(res.sendStatus.mock.calls[0].length).toBe(1);
+    expect(res.sendStatus.mock.calls[0][0]).toBe(200);
+});

app/spec/routes/getItems.spec.js

+const db = require('../../src/persistence');
+const getItems = require('../../src/routes/getItems');
+const ITEMS = [{ id: 12345 }];
+
+jest.mock('../../src/persistence', () => ({
+    getItems: jest.fn(),
+}));
+
+test('it gets items correctly', async () => {
+    const req = {};
+    const res = { send: jest.fn() };
+    db.getItems.mockReturnValue(Promise.resolve(ITEMS));
+
+    await getItems(req, res);
+
+    expect(db.getItems.mock.calls.length).toBe(1);
+    expect(res.send.mock.calls[0].length).toBe(1);
+    expect(res.send.mock.calls[0][0]).toEqual(ITEMS);
+});

app/spec/routes/updateItem.spec.js

+const db = require('../../src/persistence');
+const updateItem = require('../../src/routes/updateItem');
+const ITEM = { id: 12345 };
+
+jest.mock('../../src/persistence', () => ({
+    getItem: jest.fn(),
+    updateItem: jest.fn(),
+}));
+
+test('it updates items correctly', async () => {
+    const req = {
+        params: { id: 1234 },
+        body: { name: 'New title', completed: false },
+    };
+    const res = { send: jest.fn() };
+
+    db.getItem.mockReturnValue(Promise.resolve(ITEM));
+
+    await updateItem(req, res);
+
+    expect(db.updateItem.mock.calls.length).toBe(1);
+    expect(db.updateItem.mock.calls[0][0]).toBe(req.params.id);
+    expect(db.updateItem.mock.calls[0][1]).toEqual({
+        name: 'New title',
+        completed: false,
+    });
+
+    expect(db.getItem.mock.calls.length).toBe(1);
+    expect(db.getItem.mock.calls[0][0]).toBe(req.params.id);
+
+    expect(res.send.mock.calls[0].length).toBe(1);
+    expect(res.send.mock.calls[0][0]).toEqual(ITEM);
+});

app/src/index.js

+const express = require('express');
+const app = express();
+const db = require('./persistence');
+const getItems = require('./routes/getItems');
+const addItem = require('./routes/addItem');
+const updateItem = require('./routes/updateItem');
+const deleteItem = require('./routes/deleteItem');
+
+app.use(express.json());
+app.use(express.static(__dirname + '/static'));
+
+app.get('/items', getItems);
+app.post('/items', addItem);
+app.put('/items/:id', updateItem);
+app.delete('/items/:id', deleteItem);
+
+db.init().then(() => {
+    app.listen(3000, () => console.log('Listening on port 3000'));
+}).catch((err) => {
+    console.error(err);
+    process.exit(1);
+});
+
+const gracefulShutdown = () => {
+    db.teardown()
+        .catch(() => {})
+        .then(() => process.exit());
+};
+
+process.on('SIGINT', gracefulShutdown);
+process.on('SIGTERM', gracefulShutdown);
+process.on('SIGUSR2', gracefulShutdown); // Sent by nodemon

app/src/persistence/index.js

+if (process.env.MYSQL_HOST) module.exports = require('./mysql');
+else module.exports = require('./sqlite');

app/src/persistence/mysql.js

+const waitPort = require('wait-port');
+const fs = require('fs');
+const mysql = require('mysql2');
+
+const {
+    MYSQL_HOST: HOST,
+    MYSQL_HOST_FILE: HOST_FILE,
+    MYSQL_USER: USER,
+    MYSQL_USER_FILE: USER_FILE,
+    MYSQL_PASSWORD: PASSWORD,
+    MYSQL_PASSWORD_FILE: PASSWORD_FILE,
+    MYSQL_DB: DB,
+    MYSQL_DB_FILE: DB_FILE,
+} = process.env;
+
+let pool;
+
+async function init() {
+    const host = HOST_FILE ? fs.readFileSync(HOST_FILE) : HOST;
+    const user = USER_FILE ? fs.readFileSync(USER_FILE) : USER;
+    const password = PASSWORD_FILE ? fs.readFileSync(PASSWORD_FILE) : PASSWORD;
+    const database = DB_FILE ? fs.readFileSync(DB_FILE) : DB;
+
+    await waitPort({ 
+        host, 
+        port: 3306,
+        timeout: 10000,
+        waitForDns: true,
+    });
+
+    pool = mysql.createPool({
+        connectionLimit: 5,
+        host,
+        user,
+        password,
+        database,
+        charset: 'utf8mb4',
+    });
+
+    return new Promise((acc, rej) => {
+        pool.query(
+            'CREATE TABLE IF NOT EXISTS todo_items (id varchar(36), name varchar(255), completed boolean) DEFAULT CHARSET utf8mb4',
+            err => {
+                if (err) return rej(err);
+
+                console.log(`Connected to mysql db at host ${HOST}`);
+                acc();
+            },
+        );
+    });
+}
+
+async function teardown() {
+    return new Promise((acc, rej) => {
+        pool.end(err => {
+            if (err) rej(err);
+            else acc();
+        });
+    });
+}
+
+async function getItems() {
+    return new Promise((acc, rej) => {
+        pool.query('SELECT * FROM todo_items', (err, rows) => {
+            if (err) return rej(err);
+            acc(
+                rows.map(item =>
+                    Object.assign({}, item, {
+                        completed: item.completed === 1,
+                    }),
+                ),
+            );
+        });
+    });
+}
+
+async function getItem(id) {
+    return new Promise((acc, rej) => {
+        pool.query('SELECT * FROM todo_items WHERE id=?', [id], (err, rows) => {
+            if (err) return rej(err);
+            acc(
+                rows.map(item =>
+                    Object.assign({}, item, {
+                        completed: item.completed === 1,
+                    }),
+                )[0],
+            );
+        });
+    });
+}
+
+async function storeItem(item) {
+    return new Promise((acc, rej) => {
+        pool.query(
+            'INSERT INTO todo_items (id, name, completed) VALUES (?, ?, ?)',
+            [item.id, item.name, item.completed ? 1 : 0],
+            err => {
+                if (err) return rej(err);
+                acc();
+            },
+        );
+    });
+}
+
+async function updateItem(id, item) {
+    return new Promise((acc, rej) => {
+        pool.query(
+            'UPDATE todo_items SET name=?, completed=? WHERE id=?',
+            [item.name, item.completed ? 1 : 0, id],
+            err => {
+                if (err) return rej(err);
+                acc();
+            },
+        );
+    });
+}
+
+async function removeItem(id) {
+    return new Promise((acc, rej) => {
+        pool.query('DELETE FROM todo_items WHERE id = ?', [id], err => {
+            if (err) return rej(err);
+            acc();
+        });
+    });
+}
+
+module.exports = {
+    init,
+    teardown,
+    getItems,
+    getItem,
+    storeItem,
+    updateItem,
+    removeItem,
+};

app/src/persistence/sqlite.js

+const sqlite3 = require('sqlite3').verbose();
+const fs = require('fs');
+const location = process.env.SQLITE_DB_LOCATION || '/etc/todos/todo.db';
+
+let db, dbAll, dbRun;
+
+function init() {
+    const dirName = require('path').dirname(location);
+    if (!fs.existsSync(dirName)) {
+        fs.mkdirSync(dirName, { recursive: true });
+    }
+
+    return new Promise((acc, rej) => {
+        db = new sqlite3.Database(location, err => {
+            if (err) return rej(err);
+
+            if (process.env.NODE_ENV !== 'test')
+                console.log(`Using sqlite database at ${location}`);
+
+            db.run(
+                'CREATE TABLE IF NOT EXISTS todo_items (id varchar(36), name varchar(255), completed boolean)',
+                (err, result) => {
+                    if (err) return rej(err);
+                    acc();
+                },
+            );
+        });
+    });
+}
+
+async function teardown() {
+    return new Promise((acc, rej) => {
+        db.close(err => {
+            if (err) rej(err);
+            else acc();
+        });
+    });
+}
+
+async function getItems() {
+    return new Promise((acc, rej) => {
+        db.all('SELECT * FROM todo_items', (err, rows) => {
+            if (err) return rej(err);
+            acc(
+                rows.map(item =>
+                    Object.assign({}, item, {
+                        completed: item.completed === 1,
+                    }),
+                ),
+            );
+        });
+    });
+}
+
+async function getItem(id) {
+    return new Promise((acc, rej) => {
+        db.all('SELECT * FROM todo_items WHERE id=?', [id], (err, rows) => {
+            if (err) return rej(err);
+            acc(
+                rows.map(item =>
+                    Object.assign({}, item, {
+                        completed: item.completed === 1,
+                    }),
+                )[0],
+            );
+        });
+    });
+}
+
+async function storeItem(item) {
+    return new Promise((acc, rej) => {
+        db.run(
+            'INSERT INTO todo_items (id, name, completed) VALUES (?, ?, ?)',
+            [item.id, item.name, item.completed ? 1 : 0],
+            err => {
+                if (err) return rej(err);
+                acc();
+            },
+        );
+    });
+}
+
+async function updateItem(id, item) {
+    return new Promise((acc, rej) => {
+        db.run(
+            'UPDATE todo_items SET name=?, completed=? WHERE id = ?',
+            [item.name, item.completed ? 1 : 0, id],
+            err => {
+                if (err) return rej(err);
+                acc();
+            },
+        );
+    });
+} 
+
+async function removeItem(id) {
+    return new Promise((acc, rej) => {
+        db.run('DELETE FROM todo_items WHERE id = ?', [id], err => {
+            if (err) return rej(err);
+            acc();
+        });
+    });
+}
+
+module.exports = {
+    init,
+    teardown,
+    getItems,
+    getItem,
+    storeItem,
+    updateItem,
+    removeItem,
+};

app/src/routes/addItem.js

+const db = require('../persistence');
+const {v4 : uuid} = require('uuid');
+
+module.exports = async (req, res) => {
+    const item = {
+        id: uuid(),
+        name: req.body.name,
+        completed: false,
+    };
+
+    await db.storeItem(item);
+    res.send(item);
+};

app/src/routes/deleteItem.js

+const db = require('../persistence');
+
+module.exports = async (req, res) => {
+    await db.removeItem(req.params.id);
+    res.sendStatus(200);
+};

app/src/routes/getItems.js

+const db = require('../persistence');
+
+module.exports = async (req, res) => {
+    const items = await db.getItems();
+    res.send(items);
+};

app/src/routes/updateItem.js

+const db = require('../persistence');
+
+module.exports = async (req, res) => {
+    await db.updateItem(req.params.id, {
+        name: req.body.name,
+        completed: req.body.completed,
+    });
+    const item = await db.getItem(req.params.id);
+    res.send(item);
+};