h-Development and APIs

Creating a modern web app from scratch is very hard. This is why most of the popular web apps are developed using web frameworks.

Some of the common ones are:

• Laravel (PHP) - Usually for startups and small companies.
• Express (Node.JS) - Paypal, Yahoo, Uber, IBM
• Django (Python) - Google, Youtube, Instagram, Mozilla
• Rails (Ruby) - Github, Hulu, Twitch, Airbnb

APIs

An important aspect of back end application development is the use of Web APIs and HTTP request parameters to connect the front end and the back end.

We use APIs to connect front end with back end and ask for certain tasks to be carried out.

Query Parameters

Default method of sending argument is GET and POST.

Below is an example:

POST /search.php HTTP/1.1
...SNIP...
 
item=apples

Web APIs

API (Application Programming Interface) - Specifies how application can interact with other applications.

Example:

Twitter’s API, allows us to retrieve the latest Tweets from a certain account in XML or JSON formats, and even allows us to send a Tweet if authenticated.

Developers have to develop APIs on the back end of the web app using the API standards such as SOAP or REST.

SOAP

SOAP (Simple Objects Access) - Shares data through XML, where the request it made in XML through HTTP request and the response is also returned in XML.

Below is example SOAP message:

<?xml version="1.0"?>
 
<soap:Envelope
xmlns:soap="http://www.example.com/soap/soap/"
soap:encodingStyle="http://www.w3.org/soap/soap-encoding">
 
<soap:Header>
</soap:Header>
 
<soap:Body>
  <soap:Fault>
  </soap:Fault>
</soap:Body>
 
</soap:Envelope>

SOAP is useful for transferring structured data or even binary data.

It is also useful for sharing/changing the current state of web page.

However, SOAP is difficult to use for beginners or require long and complicated requests even for small queries. This is why READ API standard is more useful.

REST

REST (Representational State Transfer) - Shares data through the URL path. Usually returns the output in JSON format.

{
  "100001": {
    "date": "01-01-2021",
    "content": "Welcome to this web application."
  },
  "100002": {
    "date": "02-01-2021",
    "content": "This is the first post on this web app."
  },
  "100003": {
    "date": "02-01-2021",
    "content": "Reminder: Tomorrow is the ..."
  }
}