What Is A RESTful API? Explanation of REST & HTTP

Summary

This video tutorial breaks down the concept of REST APIs, explaining how they function and their importance in web technology. It simplifies the idea of APIs as intermediaries between software, using analogies like a restaurant order system and a shape-sorting toy. The presenter covers REST principles, HTTP methods, and how to interact with APIs using tools like Postman. The video also touches on authentication methods, demonstrating how to use the GitHub API with and without authentication, providing practical insights for developers.

Takeaways

• 🌐 API stands for Application Programming Interface and is a broad term for various types of interfaces, including web APIs.
• 🍽️ An analogy for understanding API is likening it to a waiter in a restaurant who takes orders (requests) and delivers meals (responses).
• 🧩 REST stands for Representational State Transfer, an architectural style for designing networked applications that rely on stateless client-server communication.
• 🔑 REST APIs use HTTP methods such as GET, POST, PUT, DELETE to interact with resources on a server.
• 📚 The video creator emphasizes explaining complex concepts like REST APIs in plain English to make them accessible to entry-level developers.
• 🌐 REST APIs treat server-side objects as resources that can be created, updated, and deleted using HTTP methods.
• 🔄 REST APIs operate using HTTP and often a standard like JSON, making them usable by virtually any programming language.
• 🔗 Endpoints are URIs or URLs where HTTP requests are sent to access or manipulate resources.
• 🔐 Authentication may be required for APIs, often implemented through OAuth, which involves obtaining an access token to include with requests.
• 🛠️ Tools like Postman can be used to test API requests without writing code, allowing for the easy sending of various types of HTTP requests.
• 🚀 The GitHub API is highlighted as a good starting point for beginners to understand and use REST APIs.

Q & A

What is the main purpose of a REST API?

A REST API is designed for networked applications and allows for the creation, updating, and deletion of server-side objects, such as blog posts in a database, using HTTP requests.

What does REST stand for and what is its role?

REST stands for Representational State Transfer. It is an architectural style for designing networked applications that rely on stateless client-server communication protocols, typically HTTP.

How does the restaurant analogy help explain what an API is?

In the restaurant analogy, the waiter acts as an API, taking a structured order (request) and bringing back a specific meal (response), illustrating how an API facilitates communication between software components.

What is an endpoint in the context of REST APIs?

An endpoint is a URI (or URL) to which HTTP requests are sent. It represents a specific resource or action that can be performed on a resource in a REST API.

What are the common HTTP methods used in REST APIs?

The common HTTP methods used in REST APIs are GET, POST, PUT, DELETE, HEAD, OPTIONS, and PATCH, with GET and POST being the most frequently used.

Why is JSON often used with REST APIs?

JSON (JavaScript Object Notation) is often used with REST APIs because it's lightweight, human-readable, and easily parsed by most programming languages, making it ideal for data interchange.

What is the difference between a REST API and a RESTful API?

A REST API is a set of guidelines for designing networked applications, while a RESTful API is an API that conforms to these REST constraints, essentially meaning they are the same thing.

How can authentication be implemented in a REST API?

Authentication in a REST API can be implemented using various methods such as OAuth, which involves obtaining an access token, or by sending client ID and secret as parameters with the requests.

What is the significance of the 200 status code in an HTTP response?

A 200 status code in an HTTP response indicates that the request has succeeded, and the response returned contains the requested data or information.

How can you test a REST API without writing code?

You can test a REST API without writing code using tools like Postman, which allows you to make various types of HTTP requests to endpoints and view the responses.

What is the GitHub API and how is it used in the script?

The GitHub API is a RESTful API that allows access to GitHub data and functionalities. In the script, it's used as a real-world example to demonstrate how to make authenticated requests and handle API rate limits.

Outlines

00:00

🌐 Introduction to REST APIs

The video begins with an introduction to REST APIs, emphasizing the aim to simplify complex concepts for beginners. The presenter clarifies the term API, standing for Application Program Interface, and explains it as a broad term applicable to various software interactions. A REST API, in particular, is focused on web APIs and operates based on HTTP requests. The video promises to demystify REST APIs with basic analogies, such as a restaurant scenario where the waiter represents the API, facilitating communication between the client (diner) and the server (kitchen). Another analogy involves a toy that only accepts certain shapes, illustrating how APIs require specific formats for requests.

05:01

🔑 Understanding RESTful Methods and Requests

This section delves into the specific methods and requests used in RESTful APIs, starting with the GET request, which is fundamental for retrieving data from a server. The presenter explains that POST requests are commonly used when submitting web forms, while PUT requests are for updating resources, typically requiring an ID to specify which resource to update. DELETE requests are used to remove resources, also needing an ID for specificity. The video also touches on less common requests like HEAD, OPTIONS, and PATCH. Examples of endpoints, or URLs where HTTP requests are sent, are provided, showing how different methods can be used on the same endpoint.

10:02

🛡️ Authentication in RESTful APIs

The script discusses the importance of authentication in RESTful APIs, explaining that while some APIs are public, others require authentication to access. It outlines various authentication methods, including OAuth, which involves obtaining an access token to include in requests. The GitHub API is used as an example to demonstrate how authentication can be implemented, either by including a token in the HTTP header or as a parameter in the URI. The presenter also mentions the need to register an application to obtain a client ID and secret, which can be used for authentication purposes.

15:03

🚀 Practical Example Using GitHub API

The final paragraph provides a practical example using the GitHub API, guiding viewers on how to make authenticated requests using tools like Postman. The presenter demonstrates how to make a GET request to retrieve user data and explains how to handle API rate limits. The process of registering an application with GitHub to obtain a client ID and secret is outlined, which is necessary for continued API access beyond the initial limit. The video concludes with a recap of the information covered and an encouragement for viewers to explore the presenter's other videos on creating RESTful APIs.

Keywords

💡REST API

REST API stands for Representational State Transfer Application Programming Interface. It is an architectural style for designing networked applications. In the context of the video, REST APIs are discussed as a way to interact with web services using HTTP requests. REST APIs are stateless and use standard HTTP methods to perform operations on resources. The video aims to demystify how REST APIs work, using simple analogies like a waiter in a restaurant to explain the concept.

💡API

API, or Application Programming Interface, is a set of rules and protocols for building and interacting with software applications. The video emphasizes web APIs, which are used for communication between different software systems over the internet. APIs act as intermediaries or messengers, facilitating requests and responses in a structured format.

💡HTTP

HTTP, or Hypertext Transfer Protocol, is the foundation of data communication on the internet. It is a protocol used by clients to request services from a server. In the video, HTTP is highlighted as the primary protocol used by REST APIs to make requests to servers and receive responses.

💡Stateless

Stateless refers to the concept in REST where each request from the client must contain all the information the server needs to fulfill the request. The server does not store any client information between requests. This is mentioned in the video as a key characteristic of REST APIs, allowing them to be scalable and efficient.

💡JSON

JSON (JavaScript Object Notation) is a lightweight data-interchange format that is easy for humans to read and write and for machines to parse and generate. The video mentions JSON as a common standard used in REST APIs for formatting the data being exchanged between the client and server.

💡GET request

A GET request is a method used in HTTP to request data from a specified resource. In the video, GET requests are described as the most common type of HTTP request, used to retrieve data from a server when a user visits a webpage or accesses an API endpoint.

💡POST request

A POST request is used to submit data to a specified resource, often causing a change in the state or side effects on the server. The video explains that POST requests are commonly used when filling out web forms, and the data submitted is not visible in the URL, unlike GET requests.

💡PUT request

A PUT request is used to update a specific resource identified by a URI. The video uses the analogy of a waiter taking an order to a kitchen to explain how PUT requests are used to update resources on the server with new data provided by the client.

💡DELETE request

A DELETE request is used to delete a specified resource identified by a URI. In the video, DELETE requests are likened to asking the server to remove a resource, similar to how a waiter might remove a dish from the menu.

💡Authentication

Authentication in the context of APIs refers to the process of verifying the identity of the client before allowing access to the API. The video discusses different methods of authentication, such as using OAuth tokens, client IDs, and secrets, to ensure that only authorized users can access the API.

💡Endpoints

Endpoints in the context of APIs are the URIs or URLs that specify the location of a resource on the server. The video explains how endpoints are used in API requests to indicate the resource the client is requesting or modifying, using examples like 'API/users' to represent a collection of user resources.

Highlights

Introduction to REST API and its basics

Explanation of what an API is in general

The role of an API as a 'messenger' or 'waiter' between software

Analogies used to explain how APIs work

REST stands for Representational State Transfer

REST is an architectural style for designing networked applications

HTTP is the foundation of REST communication

REST treats server-side objects as resources

Advantages of REST due to its use of HTTP and standards like JSON

The difference between REST API and RESTful API

Explanation of HTTP methods: GET, POST, PUT, DELETE

Endpoints are the URI or URL for HTTP requests

Examples of endpoint usage in REST APIs

Authentication in REST APIs

How to authenticate using tokens, client ID, and secret

Real-world example using GitHub API

Using tools like Postman to make API requests

How to handle API rate limits and authentication

Summary and conclusion of the video

Transcripts

hey guys welcome to another web

technology informational video in this

video we're going to talk about what a

rest API is now I do have several videos

on my channel uh showing you how to

create a rest API a couple in in

JavaScript and node and one in PHP um so

you may have seen some of those but you

you may still have some confusion on how

a rest API really works now you may be

saying well I can just Google this why

do I have to watch the V this video well

if you do Google it you'll get a

thousand different explanations that are

so complicated that it's nearly

impossible for an entry level developer

to really grasp it so I try to explain

things on a more basic level and

hopefully that's why you guys watch my

videos I try to take complicated

Concepts and explain them in plain

English uh I'm not a real sophisticated

guy so I like things spelled out without

nonsense um so that's what I try to give

my view ERS all right so before we get

into rest let's talk about what an API

is in general so it stands for

application program interface and that's

a very broad term there's all kinds of

apis uh but we're specifically talking

about web apis um there's apis in your

computer operating system in your

smartphone and even in some

refrigerators and so on so um this is

very generalized but it's essentially a

contract provided by one piece of

software to another piece of software uh

it usually consists of a structured

request and then a structured response

so one piece of software says give me

this information formatted in this way

and I'll give you this data or this

function or whatever that response may

be all right so to help you understand

we're going to take a look at a couple

analogies this first one is actually

from another YouTube video which I'll

link in the description I'm using it

because it's one of the best anal IES

I've seen so think of yourself at

sitting at a table at a restaurant um

and you're one piece of software such as

a web application on the client side and

then the kitchen is the server or the

service that processes certain requests

well the waiter is like an API he's

formatted to take a certain order in a

specific way and then bring back a

certain meal uh this would be the data

or the response that you requested so an

API is is basically a messenger or a

waiter between running

software all right so uh another good

another good analogy is this box here

this toy so if we think of this as an

API it's formatted to take certain

shapes so the client has to format the

request as a circle square or triangle

uh anything else won't be accepted

you'll get some kind of error message or

error response so this is similar to how

an API works and you can think of the

shape

as the API standard whether it's Json or

soap or something else um so to make

this operate even more like a real API

we could have some kind of output once

the formatted shape requests go in and

that would be a response okay so

hopefully this gives you a good idea as

to what an API is in

general all right so now that we talked

about what an API is let's talk about

rest so it stands for representational

State transfer and it's an architecture

style for Designing networked

applications it works on relying on a

stateless client server communication

protocol and in almost all cases this is

going to be HTTP all right you guys know

what HTTP is it's basically the the

foundation of the communication of the

internet of the web uh every time you

load a web page in your browser it's

making an HTTP request to a server

somewhere um it is possible to use other

prot calls with rest but HTTP is by far

the most used um because in order to use

real world rest you need the delivery

methods that HTTP offers um rest was

made to treat objects on the server side

as resources that can be created updated

and destroyed or deleted um an example

of a serers side object would be a blog

post in a database or something like

that okay um we can have we can create

these posts with uh a post request um a

delete with a delete request and so on

all right and what makes rest so awesome

is that uh it operates using just HTTP

uh and usually some kind of standard

like Json so it can be used by virtually

any programming language uh because most

of the the good languages can make HTTP

requests in some way whether it's PHP

JavaScript rails Java python all of

these languages are perfectly capable of

working with restful

interfaces all right so hopefully I

haven't lost you yet just remember an

API is is the messenger and rest lets us

use HTTP requests to format those

messages um you you may also hear the

term restful API and that just refers to

um conforming to the rest constraints so

rest API and restful API are essentially

the same

thing so now that we've established what

AR rest API is let's look at the

specific methods and requests that can

be made to a server through

HTTP okay so a get request is the most

common your your browser client makes

get requests every day just by going to

a specific server URI uh get requests

are used to do just that they get data

um or retrieve data from a specified

resource okay next we have a post

request and you probably use these every

day as well because every time you fill

out a web form you're making a post

request in most cases you can also make

get requests from forms but it's not

secure and the data you submit can be

seen by anyone form form tags in HTML

can take an action and a method

attribute so the action would be the

page that you're submitting to and then

the method would be either post or get

okay those are the only two requests

that can be made from just a web form on

its own so next we have put and put will

update a specified resource usually you

would have to send a request to an

endpoint which is a URI with some kind

of ID in for that specific resource

whether it's a blog post or a product um

the resource itself doesn't matter but

the server needs to know which which one

you want to update okay you can't make a

a put request from a form like you can a

post you'd have to use something like

Ajax you could use a standard JavaScript

or you could use jQuery or something

like that and then if you're using a

framework like angular um you have

different modules including an HTTP

module that's capable of sending puts

and deletes okay a delete request is

just that it will delete a specified

resource on a server and again you have

to let the server know what you're

deleting so you want to send an ID along

with that now there are other types of

requests but they're very rarely used a

head request is the same as get except

it doesn't return a body in the response

it'll only return the head info options

can be used to see the supported methods

of a server and then patch is for

partial resources updating partial

resources but we're not going to get

into

that okay so let's look at some endpoint

examples endpoints are the URI or the

URL that our HTT P requests are sent to

so here's an example using a sample API

at mysite.com

API okay you can choose whatever folder

you want to to put your uh API endpoints

in but many many times you'll use uh an

API folder or even an API subdomain okay

so this first one here is a is a um

endpoint for a get request and this

would typically just give you a list of

users okay it would return a response

with all the users and we can make a get

request to a specific user by going API

users slash and then whatever that

user's ID in many cases you may have an

endpoint like this where you're saying

instead of just users and then the ID it

would be users details and then the ID

or users show or something like that now

in this case we're making a post request

to API users and that's going to add a

user to um to the server or to the

database now notice that this get

request and this post request have the

same endpoint but since they're

different methods or different requests

that's okay okay you can use the same

the same URL but they have to be

different requests in this case here

we're making a put request to API users

one or you may see something like this

API users update one and that's going to

update that user okay okay you'll have

to send data along with that just as you

would with a post request and then

delete you can make a delete request to

API users one and that'll delete that

user okay or you may see something like

this uh users delete one okay now if we

use endpoints like the ones we just saw

without any kind of authentication of

who we are those are public or open apis

but sometimes you need to authenticate

before using them now this can mean just

register registering your app with the

provider's website and even sometimes

you'll have to pay for it you'll have to

purchase that data access so there's a

few ways that authentication is

implemented so usually you'll use ooth

which involves getting some kind of

access token and sending that along with

your requests so if you temp attempt to

make a request without that then you'll

get some kind of unauthorized error so

here's some examples of how it works

with the GitHub API which is a really

nice API for beginners it's really easy

to use um and how it works is you can

use it without any kind of

authentication but only up to I think

it's like 100 requests per hour if you

go over that and you didn't authorize

then you're going to get an error and

you're not going to be able to fetch the

data so there's a few different ways

that this is implemented in these

examples we're using curl to make our

requests curl is just basically a tool

that we can used to transfer data using

multiple protocols including

HTTP so this first one here is by

sending the token inside of the header

okay inside the HTTP header so you can

include a value for authorization and

you would set that to your token all

right sometimes you can even send the

token as a parameter in the URI and

another common way is to not send the

token itself but a generated client ID

and secret as a parameter uh to your

request all right so what I want to do

now is jump in and take a look at a real

world example we're going to look at the

GitHub API going to look at some of the

documentation and I'll show you uh what

happens when you make a get request and

we'll request some user

data all right so this is the

documentation for github's API version

three uh if you go to developer

github.com

V3 and this just basically gives you a

bunch of information on the API and most

public apis or most apis in general have

some kind of documentation like this so

you know what endpoints you need to use

what uh methods are okay to use things

like that um so if we take a look down

here uh let's see if we look

at uh HTTP verb so so these are the

different types of request that can be

made in certain endpoints so head get

post patch put and delete um it shows us

how you can authenticate and this is the

information we saw on the slide shows us

that we can authenticate through the

header through a parameter and so on uh

if we scroll down here some more it'll

also show you how to use pagination and

you can use that by requesting a certain

amount of um of whatever it is users or

repositories so in this case it's saying

100 per page and then you can also

specify the page and then you can use

your programming logic to create

pagination okay so you only so you have

100 per page and so on um let's see if

we go down some

more let's see actually that's not what

I want to show you let's go back up here

and then over here I want to click on

users okay so this gives us the how to

get a sing single user we make a get

request to/ users and then whatever that

username okay when you see a colon in

front of it like that that usually means

that this is some kind of placeholder um

so this would be whatever username you

want and then this shows you the actual

response you get okay so a 200 status

means everything's okay um and then it

gives you this in the body okay it gives

you Jason of All That user's information

including their username their ID the uh

URL to their image to their to their

Avatar um let's see how many um let's

see how many repos they have how many

gists their blog their company and then

all these URLs as well which you can

make other request to and if we go down

some

more let see update the authenticated

user so if you're authenticated as as a

specific user you can actually make

request to update your information okay

so you can edit your profile uh if you

want to get all users you can do that by

just making a get request to slash users

so what I want to do is is try this out

now you can obviously do this within

your your program but there's also tools

that you can use to make requests okay

Postman is what I suggest use you can

it's a chrome uh a Google Chrome Plugin

or extension whatever it's called so you

can go ahead and download that and then

all you have to do is put your endpoint

in here and then the type of request uh

in some cases you'll have to send data

or maybe some header values uh for

instance if you need to do authorization

you can put that in here and you can put

the value so these are key value pairs

um and if you need to send data you can

do that as well usually if you can only

send data you can't do it with a get

request you can see that's grayed out

but if it was a post request you can

send the body different formats uh you

can send it as a form or you can send

raw data for instance raw Json all right

but what I'm going to do is make a get

request to

https

api. github.com

users okay and then this is what it

gives us and you can see we have

basically it's an array of user objects

so this is the username the ID um all

the URLs and all that stuff okay now now

if we want to get a specific user we

could say we can make a get request to

I'll just put my

username send and then that gives us all

that information on that specific user

okay now with the GitHub API and a lot

of apis you can do it like this without

any kind of authentication for a certain

amount of requests in fact let me see if

I can get to it

it may yeah here we go and you can see

API rate limit has exceeded so you get a

certain amount of requests per hour or

or per every couple hours or whatever it

may be whatever they set it to um so

what we would have to do now to be able

to keep using this in our application is

to register it okay so if we go to

github.com settings applications new and

let's say test app homepage

just say

test.com application

description just say my app and then

some kind of callback URL we'll just

take this and let's say register

application and now you can see it gives

us a client ID and a client secret so

what we have to do now is just include

these as a parameter okay so if we go

back to our documentation here and go

down to uh where is it

authentication so we can add we can send

these as a parameter you can see right

here client ID client secret so let's

take that starting with that question

mark and go back to

postman and we'll just grab the client

ID and we'll put that right here place

these these x's and then the

secret and we'll put

that right here we don't want that quote

on the end and now let's make let's do

send and now we can get it okay we can

keep making them because we're

authenticated all right so that's going

to be it for this video hopefully this

gives you guys a better idea on how uh

restful apis work and if you haven't

seen my videos where we create a restful

API I would suggest doing that all right

so that's it thanks for watching and I

will see you next time