Name: API Essentials - 03 What is a REST API?（What is a REST API?）
Uploaded: 2022-05-11T02:23:26.000Z
Duration: 9 min 12 s
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- and how are they fundamental to your cloud application development?

and I'm going to answer that for you today,

but before i do please hit that subscribe button.

Let's say that you work for an ice cream shop

and you're trying to build a web application

to show the flavors of ice cream that are in stock that day

and allow the workers to actually make updates to those flavors.

You have your web app or web page communicate with a cloud-based server

So, let's jump into what exactly a REST API is.

Starting out with: what does "REST" stand for?

So, REST stands for Representational State Transfer.

Those words might not mean a whole lot to you

but, basically, it's a standardized software architecture style,

a specific type of API that's industry known and used.

So, the first thing that you should really know about  REST APIs

So, client with server and vice versa - that's how they talk,

and also you may have heard the term "restful".

So, "restful web service", right, that's a service that uses REST APIs to communicate.  

So, what are some of the benefits of REST APIs?

First of all, they're a simple and standardized approach to communication.

You don't have to worry about how to format your data,

or how to format your request each time -

Second of all, REST APIs are scalable and stateless.

So, as your service grows in complexity you can easily make modifications  

and just the fact that they're stateless means you don't have to worry about

what data is in which state and keep track of that across client and server.

in large part due to the fact that they support caching.

So, that's all all good stuff - as your service gets more complex

So, for the ice cream shop, what would the REST API look like?

So, you have an endpoint which might look something like this:

Right? So, let's break that apart a bit.

So, "api" this just signifies that this is the API portion of the endpoint.

Right? So, pretty straightforward there.

"Flavors" is actually what's known as a "resource".

So, this signifies that we're working with the flavors resource in this this REST API.

the main building blocks, or parts, of the REST API are:

the "request", that is sent from the client to the server,

and the "response", that is received back from the the server.

So, let's let's break those apart a little bit.

Over here, let's put a big old box for request,

and what are the type of things that you might want to do with a REST API?

What actions or verbs would you want to make when you're working with one?

You may have heard of "CRUD" - what does CRUD stand for?

So, CRUD is "Create, Read, Update, and Delete".

These are some of the main things that you might want to do

when you're communicating with your client and server.

On a REST API, the equivalent of those are are actually HTTP "methods"

So, what's the equivalent of "create" in an HTTP method?

... and delete? Guess what it is: "delete".

So, first of all, you might have an operation,

that's kind of what we just talked about here with the HTTP methods,

which is what we just talked about over here -

and then you might also have parameters or body,

which is some data that you might send in the request,  

and we'll see some examples in a moment,

So, this is a special part of an REST API request   

which might have things like an API key or some authentication data.

Great - and then, in return, from the server, you'll receive a response, right?

So, we'll put a nice box here for response

and this is typically in the form of JSON data.

and let's look at a few different scenarios that might happen with your ice cream shop, right?

let's say that you want to display what's currently in stock, right?

So, we want to get the flavors that are in stock.

So, what does our rest API request look like?

because you're actually wanting to get those flavors,

and then the end point is "/api/flavors",

and, in response, you'll get an array of those flavor resources, right?

So, we see strawberries in stock, as well as mint chocolate ... yummy!