fredrikaverpil / typescript-nodejs-express

Example Express REST API

typescript-nodejs-express

• Node.js executes JavaScript, not TypeScript.
• We'll use tsc to compile ts->js and then have nodemon serve the js app.

Setup (this was already done)

nvm install --lts
nvm use --lts
node -v > .nvmrc

npm init  # set up package.json
npm install typescript
node_modules/typescript/bin/tsc --init  # create tsconfig.json

In tsconfig.json, set target, moduleResolution, outDir and rootDir accordingly.

npm install --save express body-parser
npm install --save-dev nodemon

Install types:

npm install --save-dev @types/node @types/express

Add a new start script to package.json:

"start": "nodemon dist/app.js"

Run

node_modules/typescript/bin/tsc -w
npm start  # the new start script we added to package.json

Perform REST API calls

Launch e.g. Postman or Thunder Client in vscode, then send a POST request to http://localhost:3000/todos/ with json {"text": "hello world"}. This will add a todo. Example response:

{
  "message": "Created the todo.",
  "createdTodo": {
    "id": "0.4701661299147384",
    "text": "hello"
  }
}

Making a GET request to http://localhost:3000/todos/ will return all todos in the response.

A todo can be updated by making a PATCH request to http://localhost:3000/todos/$ID (where $ID is one of the ids returned in the previous GET request) with json data {"text": "updated value"}.

This would return a response such as:

{
  "message": "Updated!",
  "updatedTodo": {
    "id": "0.527784891057566",
    "text": "updated value"
  }
}