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Insomnia Quick Start — Cheat Sheet

An evergreen reference for testing your API with Insomnia. First taught in API Lesson 1; used to verify every endpoint for the rest of the pass. Insomnia lets you send HTTP requests and inspect responses without building a front end — so you can prove your API works the moment you write it.

Insomnia cheat sheet: why we use Insomnia, the CRUD operations (CREATE/READ/UPDATE/DELETE/LIST), and quick tips

One caveat for this course: the sheet above has an "Authentication Testing" section showing register → get a token → send Authorization: Bearer …. This course has no JWT and no tokens. Login just verifies a username/password and returns the user object; every endpoint is open, so you never attach an Authorization header and never get a 401. Use the CRUD half of the sheet — ignore the token/auth half.

What Insomnia does

It's a desktop app for sending HTTP requests. You pick a verb and URL, add a body if needed, hit Send, and read the status code and response body. That's the whole loop — the same request/response a browser or your React app makes, but on demand and easy to inspect.

The five things you'll do map straight to CRUD:

In Insomnia Verb Example
Create POST POST /api/menuitems with a JSON body
Read GET GET /api/menuitems or GET /api/menuitems/5
Update PUT PUT /api/menuitems/5 with a JSON body
Delete DELETE DELETE /api/menuitems/5
List / filter GET GET /api/orders?status=PLACED

Set-up (once)

  1. Install Insomnia from insomnia.rest and open it.
  2. Import the collection — File → Import, choose the provided tableserve-insomnia.json. The TableServe collection appears with a folder per entity (Auth, Staff, Categories, MenuItems, Orders, OrderItems).
  3. Set baseUrl — run your API in Visual Studio (F5), note the port (e.g. https://localhost:7234), then in Insomnia set the baseUrl environment variable to that address. Every request uses {{ baseUrl }} so you only set the port once.

No login required first. Because every endpoint is open, you don't have to run Login before anything else — the requests work regardless. Login is just there to confirm your credentials and show the shape of a user object.

Anatomy of a request in Insomnia

  • Method dropdown — GET / POST / PUT / DELETE.
  • URL bar — e.g. {{ baseUrl }}/api/staff/5.
  • Body tab — for POST/PUT, choose JSON and type the object. Insomnia sets the Content-Type: application/json header for you.
  • Send — fires the request.

Reading the response

  • Status code (top of the response panel) — check it first: 200/201/204 = success, 400/404 = your request, 500 = the server. (See the HTTP & status codes cheat sheet.)
  • Body — the JSON returned.
  • Tests tab — the provided requests have after-response tests. Green = pass, red = fail. A wall of green means your API matches the contract. If one is red, the panel shows expected vs. received — open that controller and compare.

Connection error? The API stopped running — press F5 again and confirm the port matches your baseUrl. (There's no auth, so there's no 401 to chase.)

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