build-a-restful-api-with-laravel-400x277.png

This course will begin our journey into Application Programming Interface(API) Development with Laravel.  In this course, we will be going over topics like:
- Concept of Application Programming Interface (API)  and its benefits, 
- Representational State Transfer (REST) Architecture and its constraints, 
- JSON Web Token (JWT) for authentication, 
- best practices for designing a RESTful API, and much more.

We will be putting this knowledge into practical use by building a Question & Answer Restful API Application.

Application Features

- Users can signup and sign in.
- Users can reset their passwords.
- Authenticated users can post a question.
- Authenticated users can answer a question.
- The question owner can delete his question.
- Answer owner can delete his answer.

This course requires an understanding of PHP and a basic understanding of the Laravel framework. 

By the end of this course, we will be able to begin our journey in creating RESTful APIs in Laravel.

Building a Question & Answer RESTful API Application

## Introduction

HTTP defines several methods for standard operations on a resource. HTTP method or HTTP verbs indicate the action to be performed on a resource by the server. 
HTTP methods help to understand the client's intention behind a request.

## Types of HTTP methods

The most common HTTP methods are GET, POST, PUT and DELETE. These HTTP methods are used mainly for **CRUD**(Create-Retrieve-Update-Delete) operations.

1. **GET:** The GET method retrieves data or information from a specified resource.  A GET request should not modify a resource.

2. **POST:** The POST method creates a resource or executes tasks like calculating payments or sending emails. In some cases, the POST method can update a resource. 

3. **PUT:** The PUT method updates a target resource. A PUT request replaces the entire representation of the target resource with the request payload.

4. **DELETE:** The DELETE method deletes a target resource.

5. **PATCH:** The PATCH method updates a target resource partially. 
The difference between PUT and PATCH is, for a PUT request, the payload sent to the server is considered a modified version of a resource, and the client is requesting that server overwrites the previously stored data. For a PATCH request, the server modifies only the partial data sent by the client instead of overwriting the entire data.

6. **HEAD:** Like the GET method, the HEAD method retrieves data, except the server will return no response body. Instead, the server will return only header information to the client. The header information returned is assumed to describe the response which a similar GET request would have received.

7.  **OPTIONS:** The OPTIONS method doesn't invoke any action or operation on the resource but provides necessary information about communicating with a resource.
 
## Safe methods

An HTTP method is safe if it does not modify the state of a resource or has no side effect on the server like sending emails. GET, HEAD, and OPTIONS methods are considered safe.


## Idempotent methods

> Idempotence is the property of specific mathematics and computer science operations that can be applied multiple times without changing the result beyond the initial application.
-- <cite>Wikipedia</cite>


An example of idempotence is multiplication by 1. No matter how many times a number is multiplied by one, the result remains the same. An HTTP method is idempotent if multiple identical requests do not have different outcomes. Idempotent methods, if executed once or five times, the result remains the same.

GET, HEAD, OPTIONS, PUT, and DELETE methods are idempotent, but the POST method is not idempotent. All idempotent methods are safe methods, but not all safe methods are idempotent. The PATCH method is not idempotent, but there is no restriction to make PATCH operations on your server idempotent. There are other HTTP methods like CONNECT, TRACE, etc., but outside the scope of this course.


# Introduction

HTTP defines several methods for standard operations on a resource. HTTP method or HTTP verbs indicate the action to be performed on a resource by the server. 
HTTP methods help to understand the client's intention behind a request.

# Types of HTTP methods

The most common HTTP methods are GET, POST, PUT and DELETE. These HTTP methods are used mainly for **CRUD**(Create-Retrieve-Update-Delete) operations.

1. **GET:** The GET method retrieves data or information from a specified resource.  A GET request should not modify a resource.

2. **POST:** The POST method creates a resource or executes tasks like calculating payments or sending emails. In some cases, the POST method can update a resource. 

3. **PUT:** The PUT method updates a target resource. A PUT request replaces the entire representation of the target resource with the request payload.

4. **DELETE:** The DELETE method deletes a target resource.

5. **PATCH:** The PATCH method updates a target resource partially. 
The difference between PUT and PATCH is, for a PUT request, the payload sent to the server is considered a modified version of a resource, and the client is requesting that server overwrites the previously stored data. For a PATCH request, the server modifies only the partial data sent by the client instead of overwriting the entire data.

6. **HEAD:** Like the GET method, the HEAD method retrieves data, except the server will return no response body. Instead, the server will return only header information to the client. The header information returned is assumed to describe the response which a similar GET request would have received.

7.  **OPTIONS:** The OPTIONS method doesn't invoke any action or operation on the resource but provides necessary information about communicating with a resource.
 
# Safe methods

An HTTP method is safe if it does not modify the state of a resource or has no side effect on the server like sending emails. GET, HEAD, and OPTIONS methods are considered safe.


# Idempotent methods

> Idempotence is the property of specific mathematics and computer science operations that can be applied multiple times without changing the result beyond the initial application.
-- <cite>Wikipedia</cite>


An example of idempotence is multiplication by 1. No matter how many times a number is multiplied by one, the result remains the same. An HTTP method is idempotent if multiple identical requests do not have different outcomes. Idempotent methods, if executed once or five times, the result remains the same.

GET, HEAD, OPTIONS, PUT, and DELETE methods are idempotent, but the POST method is not idempotent. All idempotent methods are safe methods, but not all safe methods are idempotent. The PATCH method is not idempotent, but there is no restriction to make PATCH operations on your server idempotent. There are other HTTP methods like CONNECT, TRACE, etc., but outside the scope of this course.


Learn about the different types of HTTP methods and how to distinguish between the safe and idempotent methods.

Getting Started

Introduction to API Assessment

Quick Refresher

Authentication

Create Question Endpoints

Create Answer Endpoints

Tags

Database Seeding

Password Reset

Conclusion

HyperText Transfer Protocol (HTTP) Methods

Introduction

Types of HTTP methods