Getting Started with cURL

What is cURL?

cURL which stands for client URL and can be written as curl , is a command line tool for file transfer with a URL syntax. It supports a number of protocols including HTTP, HTTPS, FTP, and many more. HTTP/HTTPS makes it a great candidate for interacting with APIs!

curl can be used on just about any platform on any hardware that exists today. This means, regardless of what you are running and where, the most basic curl commands should just work. None of the usual “it doesn’t work on my machine”

Why Me (Programmer🥺) Need cURL

I use cURL because it helps them:

• Test APIs without writing code

• Debug backend services

• Check server responses quickly

• Understand HTTP deeply

• Reproduce issues exactly

If you work with APIs, backend systems, or DevOps, cURL becomes a daily tool.

Now lets do some laundry

lets pull something from actual website using curl command

for example il do pull data from my resume website

curl https://www.jatin4224.info/

output

by default the curl command will disply the output in our terminal but i want to get output in file so for that i’ll use command

curl https://www.jatin4224.info/ -o output.html

📁 Where is the file saved?

The file is saved in your current directory.

Check it with:

dir

If you want to save it somewhere else:

curl <https://www.jatin4224.info/> -o C:\\Users\\Jatin\\Desktop\\site.html

Now, let's create more GET and POST API requests using cURL. But before that, I want to explain the concept of requests and responses.

What is a request?

A request simply means asking for something. In web applications, the frontend asks the server (backend) for a resource. Since the frontend cannot directly access server data, it sends a request to the server.

A request is not only used to get data. It can also be used to:

• Create new data

• Update existing data

• Delete data

Examples of requests

For a Todo app, common requests are:

• Create a Todo

• Update a Todo

• Read a Todo

What is a response?

A response is what the server sends back after receiving a request.

If a request is a question, the response is the answer.

What does a response contain?

A response usually includes:

• Status code: a number that tells whether the request was successful or not

• Headers: extra information about the request and response

• Response body: the actual data returned by the server (for example, a list of todos)

Now, I’m building a Todo app. To test my API, I don’t have Postman, so I’m using cURL to test my GET, POST, and DELETE APIs.

Todo API Structure

GET     /api/todos
POST    /api/todos
DELETE  /api/todos/:id

Base URL:

<https://www.jatin4224.info>

GET Request (Read Todos)

A GET request is used to fetch data from the server.

Get all todos

curl <https://www.jatin4224.info/api/todos>

This sends a request to the backend and returns a list of todos, usually in JSON format.

Get a single todo

curl <https://www.jatin4224.info/api/todos/1>

This fetches the todo with ID 1.

POST Request (Create a Todo)

A POST request is used to send data to the backend and create a new resource.

curl -X POST <https://www.jatin4224.info/api/todos> ^
-H "Content-Type: application/json" ^
-d "{\\"title\\":\\"Learn curl\\",\\"completed\\":false}"

DELETE Request (Delete a Todo)

A DELETE request removes data from the backend.

curl -X DELETE <https://www.jatin4224.info/api/todos/1>

The backend deletes the todo and sends back a confirmation response.