CPNT 262 Day 22 - Handling POST Requests with Mongoose

Housekeeping

• Tony needs fancy features for approval
• Tweaks to Final Project

Trophy of the day

• Deployed express server with mongoose

1. POST requests with request.body and express.urlencoded()

Materials

• Express: Handling POST Requests
• Starter Code: Guild with Mongoose

Key Takeaways

• The request object stores parameters in three main objects:

  1. req.params: Parameters passed as route segments.
     • Example: GET /api/animals/:id.
  2. req.query: Parameters passed after the ? in a URL.
     • Example: /api/animals?page=3&per_page=10.
  3. req.body: Parameters passed in the request body, such as when a form is submitted with method="POST".

• req.body is only available if you add the following middleware to your server file:

  app.use(express.urlencoded({ extended: true }));

• Alternatively, you can add the following if the form was submitted in JSON format (not covered in this course):

  app.use(express.json());

  • Both can be added at the same time and both will process POST form parameters and add them to req.body

• The form submission is handled by app.post() at the same path as your list entry endpoint. The method is set by the method attribute in your form:

  app.post('/api/kittens', () => {...})

2. Creating Mongoose records

Materials

• CRUD Operations with Mongoose and MongoDB Atlas
• Gist: Create Mongoose document from form data in Express

Key Takeaways

• Saving a record with Mongoose requires two steps:

  1. Creating a model instance, passing an object containing the information submitted by the form.

     const kitten = new Kitten(req.body)

  2. Saving the instance with model.save():

     await kitten.save()

• Since we didn't cover view engines in express, we will be redirecting to static success and fail pages depending on the result of the .save()

  response.redirect('/success.html')

  OR

  response.redirect('/fail.html')

3. Deploying to Heroku with Atlas

Materials

• How to host a RESTful Node.js server with MongoDB Atlas database on Heroku
  • Note:
    • CORS headers are often not needed with Atlas... but sometimes they are.
    • We will be connecting to Mongoose a little differently that what is shown in this article.

Key Takeaways

• Most of the steps in this tutorial were completed yesterday so you should only have to complete the following to have your Heroku connect to Atlas:
  • Add your connection string to the Config Var section of your App Settings with a name of MONGODB_URL (Important: Heroku won't connect to Atlas properly unless you use this variable name).
• Note: CORS is probably not needed for your app to operate.

Lab Time

• Trophy of the day
• Assignment 5
• Final Project

Prep

POST Requests with Express and Mongoose

• Handle GET and POST Request in Express
  • Note: We don't need to require body-parser as of Express 4.16
• Gists:
  • Read MongoDB data with Mongoose and Express
  • Express: Handling POST Requests
  • Create Mongoose document from form data in Express

Deploying with Atlas on Heroku

• How to host a RESTful Node.js server with MongoDB Atlas database on Heroku
  - Note:
  - CORS headers are often not needed with Atlas... but sometimes they are.
  - We will be connecting to Mongoose a little differently that what is shown in this article.