What's this?

This is a demo project created while following the Build A Restful Api With Node.js Express & MongoDB.

I did this tutorial as a followup after dotnet-core-mvc-rest-api to compare two technologies.

NPM Packages

express - web server
nodemon - watches for source changes & restarts node app
mongoose - client for MongoDB
body-parser - parses request JSON body into object

Express Notes

Messages in Express are processed via a simple pipeline consisting of

middleware = functions which are called first and which can modify request
route handlers = functions registered to be called for a specific route and request type

Express Middleware

Middleware is registered via add method of the Express. In this example we use two middlewares:

bodyParser - converts requst body (JSON) into JavaScript objects
router - calls route handlers

Express router

Route handler functions are registered via a method named after the corresponds HTTP request type:

post = POST request handler
get = GET request handler
delete = DELETE request handler
etc...

While registering a handler we specify the URL to which the handler will respond. The URL string can contain parameter placeholders which will get passed to the requst handler function.

Sending response

Response is sent to client via resp object which is passed to the handler function as an argument.

Here's an example showing how to respond with HTTP status 200 and a JSON response type:

resp.status(200).json(savedPost);

MongoDB

Mongoos npm package is used to access the MongoDB database.

Querying is done via a model object of type Schema. In model we describe the structure of the record stored in the DB, while the Schema methods we can use to query the database. Here are a few examples:

save - adds record to the database
deleteOne - deletes one record from the database
find - finds a record in the DB