Add typescript to files

index.ts

@@ -0,0 +1,2 @@
+#!/usr/bin/env node
+import "./src/command.ts"

package.json

@@ -2,10 +2,9 @@
   "name": "node_tutorial",
   "version": "1.0.0",
   "description": "",
-  "main": "index.js",
   "type": "module",
   "bin": {
-    "note": "./index.js"
+    "note": "index.ts"
   },
   "scripts": {
     "test": "node --experimental-vm-modules node_modules/jest/bin/jest.js"
@@ -25,5 +24,8 @@
     "jest": "^29.6.4",
     "open": "^9.1.0",
     "yargs": "^17.7.2"
+  },
+  "devDependencies": {
+    "typescript": "^5.2.2"
   }
 }

src/command.js → src/command.ts

@@ -1,9 +1,29 @@
 import yargs from 'yargs'
 import { hideBin } from 'yargs/helpers'
-import {newNote, getAllNotes, findNotes, removeNote, removeAllNotes} from './notes.js'
+import {newNote, getAllNotes, findNotes, removeNote, removeAllNotes} from './notes.ts'
 import { start } from './server.js'
 
-const listNotes = (notes) => {
+interface Note {
+  id: number;
+  content: string;
+  tags: string[];
+}
+
+interface NewNoteArgs {
+  note: string;
+  tags?: string;
+}
+
+interface FindNotesArgs {
+  filter: string;
+}
+
+interface RemoveNoteArgs {
+  id: number;
+}
+
+
+const listNotes = (notes: Note[]) => {
   notes.forEach(note => {
     console.log('\n')
     console.log('id: ', note.id)
@@ -13,7 +33,7 @@ const listNotes = (notes) => {
 }
 
 yargs(hideBin(process.argv))
-  .command('new <note>', 'create a new note', yargs => {
+  .command<NewNoteArgs>('new <note>', 'create a new note', yargs => {
     return yargs.positional('note', {
       describe: 'The content of the note you want to create',
       type: 'string'
@@ -32,7 +52,7 @@ yargs(hideBin(process.argv))
     const notes = await getAllNotes()
     listNotes(notes)
   })
-  .command('find <filter>', 'get matching notes', yargs => {
+  .command<FindNotesArgs>('find <filter>', 'get matching notes', yargs => {
     return yargs.positional('filter', {
       describe: 'The search term to filter notes by, will be applied to note.content',
       type: 'string'
@@ -41,7 +61,7 @@ yargs(hideBin(process.argv))
     const notes = await findNotes(argv.filter)
     listNotes(notes)
   })
-  .command('remove <id>', 'remove a note by id', yargs => {
+  .command<RemoveNoteArgs>('remove <id>', 'remove a note by id', yargs => {
     return yargs.positional('id', {
       type: 'number',
       description: 'The id of the note you want to remove'

src/db.js → src/db.ts

@@ -2,6 +2,16 @@ import fs from 'fs/promises';
 import path from 'path';
 import { fileURLToPath } from 'url';
 
+interface Note {
+  tags: string[];
+  content: string;
+  id: number;
+}
+
+interface Database {
+  notes: Note[];
+}
+
 const DB_FILE_NAME = 'db.json';
 
 const __filename = fileURLToPath(import.meta.url);
@@ -19,7 +29,7 @@ export const getDB = async () => {
   }
 };
 
-export const saveDB = async (db) => {
+export const saveDB = async (db: Database) => {
   try {
     await fs.writeFile(DB_PATH, JSON.stringify(db, null, 2));
     return db;
@@ -28,7 +38,7 @@ export const saveDB = async (db) => {
   }
 };
 
-export const insert = async (data) => {
+export const insert = async (data: Note) => {
   try {
     const db = await getDB();
     db.notes.push(data);

src/notes.js → src/notes.ts

@@ -1,6 +1,6 @@
 import { insert, getDB, saveDB } from './db.js'
 
-export const newNote = async (note, tags) => {
+export const newNote = async (note: string, tags: string[]) => {
   const data = {
     tags,
     id: Date.now(),
@@ -14,17 +14,17 @@ export const getAllNotes = async () => {
   return db.notes
 }
 
-export const findNotes = async (filter) => {
+export const findNotes = async (filter: string) => {
   const notes = await getAllNotes()
-  return notes.filter(note => note.content.toLowerCase().includes(filter.toLowerCase()))
+  return notes.filter((note: { content: string }) => note.content.toLowerCase().includes(filter.toLowerCase()))
 }
 
-export const removeNote = async (id) => {
+export const removeNote = async (id: number) => {
   const notes = await getAllNotes()
-  const match = notes.find(note => note.id === id)
+  const match = notes.find((note: { id: number }) => note.id === id)
 
   if (match) {
-    const newNotes = notes.filter(note => note.id !== id)
+    const newNotes = notes.filter((note: { id: number }) => note.id !== id)
     await saveDB({notes: newNotes})
     return id
   }

src/server.js → src/server.ts

@@ -2,13 +2,20 @@ import fs from 'node:fs/promises'
 import http from 'node:http'
 import open from 'open'
 
-const interpolate = (html, data) => {
+interface Note {
+  id: number;
+  content: string;
+  tags: string[];
+}
+
+
+const interpolate = (html: string, data: { [x: string]: any; notes?: string; }) => {
   return html.replace(/\{\{\s*(\w+)\s*\}\}/g, (match, placeholder) => {
     return data[placeholder] || '';
   });
 }
 
-const formatNotes = (notes) => {
+const formatNotes = (notes: Note[]) => {
   return notes.map(note => {
     return `
       <div class="note">
@@ -21,7 +28,7 @@ const formatNotes = (notes) => {
   }).join('\n')
 }
 
-const createServer = (notes) => {
+const createServer = (notes: Note[]) => {
   return http.createServer(async (req, res) => {
     const HTML_PATH = new URL('./template.html', import.meta.url)
     const template = await fs.readFile(HTML_PATH, 'utf-8')
@@ -32,7 +39,7 @@ const createServer = (notes) => {
   });
 }
 
-export const start = (notes, port) => {
+export const start = (notes: Note[], port: number) => {
   const server = createServer(notes)
   server.listen(port, () => {
     console.log(`Server is listening on port ${port}`);

tsconfig.json

@@ -0,0 +1,18 @@
+{
+    "compilerOptions": {
+      "target": "ES2020",
+      "module": "ESNext",
+      "outDir": "./dist",
+      "rootDir": "./src",
+      "strict": true,
+      "esModuleInterop": true,
+      "skipLibCheck": true,
+      "moduleResolution": "node",
+      "allowImportingTsExtensions": true,
+      "noEmit": true,
+      "forceConsistentCasingInFileNames": true
+    },
+    "include": ["src/**/*.ts"],
+    "exclude": ["node_modules"]
+  }
+