Understanding What are HTTP Methods (GET, POST, PUT, DELETE)

Hello, in this article, I will explain the essential concepts of HTTP methods and how they are used in web communication. HTTP methods are an integral part of building web applications and interacting with APIs. By understanding these methods, you will be able to effectively retrieve and modify resources on the server.

Before diving into the details, let’s take a moment to understand what HTTP methods are and why they are important. HTTP, or Hypertext Transfer Protocol, is the foundation of data communication on the World Wide Web. It defines a set of request methods that clients can use to communicate with servers.

The primary HTTP methods used for web communication are GET, POST, PUT, and DELETE. These methods correspond to different operations such as creating, reading, updating, and deleting resources. The HTTP protocols define how these methods are used in communication between clients and servers. It is essential to understand these methods to effectively interact with APIs and build web applications.

Key Takeaways:

• HTTP methods are used for web communication and define different operations on resources.
• The primary HTTP methods are GET, POST, PUT, and DELETE.
• HTTP protocols govern how these methods are used between clients and servers.
• Understanding HTTP methods is crucial for building web applications and interacting with APIs.
• GET is used for retrieving resources, POST for creating resources, PUT for updating resources, and DELETE for deleting resources.

Understanding GET Method

The GET method is an essential part of HTTP request types. It is primarily used to retrieve information from a server. When a client makes a GET request, it sends a request to the server to fetch a specific resource. The server then responds by returning a representation of the requested resource.

In the context of HTTP methods, GET is a read-only method, meaning it does not modify any data on the server. It is considered a safe method, as it does not have any side effects on the server or the resources it interacts with. Additionally, GET requests are idempotent, which means that making identical requests multiple times will produce the same result.

It is important to note that GET requests should not be used for modifying resources on the server. They are specifically designed for retrieving data. If you need to create, update, or delete resources, you should use the appropriate HTTP methods, such as POST, PUT, or DELETE, respectively.

Understanding POST Method

The POST method is an essential HTTP request method used in web communication. It allows clients to create new resources on the server. When making a POST request, the client sends data to the server, which then uses that data to create a new resource. Unlike the GET method, which is read-only, the POST method modifies the server-side resources by adding new data.

The POST method is not idempotent, meaning that making multiple identical requests may result in the creation of duplicate resources. It is crucial to use the POST method carefully and consider its implications on the server when handling non-idempotent operations. Developers should be aware that when using the POST method, it may have an impact on the server’s resources and should be reserved for creating new resources.

It is important to note that the POST method is just one of several HTTP request methods available for different operations on resources. By understanding the purpose and characteristics of each method, developers can choose the most suitable method for their specific use cases.

Comparing POST Method with other HTTP Methods

When comparing the POST method with other HTTP methods, it is essential to consider their specific purposes and characteristics. Unlike the GET method, which retrieves data, the POST method is used for creating new resources. Additionally, the POST method is not idempotent, meaning that multiple identical requests may result in duplicate resources being created on the server.

On the other hand, the PUT method is typically used for updating existing resources, while the DELETE method is used to delete specified resources. Both PUT and DELETE methods can modify server-side resources, and they differ from the POST method in terms of their specific use cases and characteristics.

By comparing and understanding the differences between these HTTP methods, developers can make informed decisions when designing and implementing web applications.

Understanding PUT Method

The PUT method is an HTTP request method used to update an existing resource on the server. When making a PUT request, the client sends a complete representation of the updated resource in the request body. The server then replaces the existing resource with the new representation provided. PUT requests are not idempotent, meaning that multiple identical requests may result in different outcomes. However, PUT can be used for both updating and creating resources.

Unlike the POST method, which creates a new resource, the PUT method is specifically used for updating existing resources. It requires the client to send the entire representation of the resource, including any fields that are unchanged. This ensures that the server has the most up-to-date information for the resource being updated.

The PUT method is particularly useful in situations where the client wants to modify specific fields of a resource without affecting other fields. By providing the complete representation of the updated resource, the client can ensure that only the intended changes are made on the server. This allows for precise updates and minimizes the risk of unintended modifications to the resource.

Understanding DELETE Method

The DELETE method is one of the primary HTTP request methods used for web communication. It is used to delete a specified resource from the server. When making a DELETE request, the client sends a request to remove the resource identified by its URI (Uniform Resource Identifier). This method is commonly used in RESTful APIs for deleting data.

The HTTP DELETE method is considered idempotent, meaning that multiple identical requests will produce the same result of removing the resource. However, it’s important to note that calling DELETE on a resource that has already been deleted may result in a 404 status code, indicating that the resource is no longer available.

Here is an example of a DELETE request using cURL:

curl -X DELETE https://api.example.com/users/123

This DELETE request would delete the user with the ID 123 from the server. It’s crucial to ensure that the client has the necessary permissions and authorization to perform the delete operation.

Understanding the DELETE method is crucial for managing resources in web applications and APIs. It provides a way to remove data permanently from the server and helps maintain a clean and up-to-date data model.

Comparing HTTP Methods

When working with web communication and APIs, it is important to understand the differences between the various HTTP methods available. Each method serves a specific purpose and has its own set of characteristics. Let’s take a closer look at the four primary HTTP methods: GET, POST, PUT, and DELETE.

The GET method is used for retrieving information from a server. It is a read-only method that does not modify data. GET requests are considered safe and idempotent, meaning they can be called without changing the resource’s state and producing the same result each time. This makes GET requests suitable for retrieving data from a server.

On the other hand, the POST method is used for creating new resources on the server. When making a POST request, the client sends data to the server, which then creates a new resource based on that data. POST requests are not idempotent, meaning that making multiple identical requests may result in duplicate resources. This makes POST requests suitable for submitting data and creating new resources.

The PUT method is typically used to update an existing resource on the server. When making a PUT request, the client includes a complete representation of the updated resource in the request body. The server then replaces the existing resource with the new representation. PUT requests are not idempotent, but they can be used for both updating and creating resources. This makes PUT requests suitable for modifying existing resources.

Lastly, the DELETE method is used to delete a specified resource from the server. When making a DELETE request, the client sends a request to remove the resource identified by its URI. DELETE requests are idempotent, meaning that multiple identical requests will produce the same result of removing the resource. This makes DELETE requests suitable for deleting resources from a server.

Summary:

• The GET method is used for retrieving information.
• The POST method is used for creating new resources.
• The PUT method is used for updating existing resources.
• The DELETE method is used for deleting resources.

By understanding the differences between these HTTP methods, developers can choose the most appropriate method for each task and effectively communicate with servers and APIs.

Examples of HTTP Methods in Action

To illustrate how HTTP methods are used in practice, let’s take a look at some examples:

Example 1: GET Request

Suppose you want to retrieve information about a specific product from an online store. In this case, you would make a GET request to the server, specifying the unique identifier of the product. The server would then respond with the requested data, such as the product name, price, and description.

GET Request: GET /products/{product_id}

This example showcases the GET method’s usage for retrieving resources from a server.

Example 2: POST Request

Let’s say you want to add a new user to a social media platform. To accomplish this, you would make a POST request, sending the required user details (name, email, password, etc.) as the request’s payload. The server would then process the request and create a new user account based on the provided data.

POST Request: POST /users

This example demonstrates how the POST method is used to create new resources on the server.

Example 3: PUT Request

Suppose you have a blog post that contains a typo, and you want to correct it. To update the post, you would make a PUT request, sending the updated content and the unique identifier of the post. The server would receive the request, replace the existing post with the new content, and return a success response.

PUT Request: PUT /posts/{post_id}

This example highlights the PUT method’s usage for modifying existing resources on the server.

Example 4: DELETE Request

Imagine you want to remove a comment from a discussion forum. To accomplish this, you would make a DELETE request, specifying the identifier of the comment to be deleted. The server would then delete the comment from the database and respond with a success status code.

DELETE Request: DELETE /comments/{comment_id}

This example showcases how the DELETE method is used to delete specific resources from the server.

The table summarizes the examples discussed above, providing a clear overview of each HTTP method’s purpose and usage.

Conclusion

Understanding HTTP methods is essential for effective web communication and seamless API integration. The four primary HTTP methods – GET, POST, PUT, and DELETE – cater to different operations performed on resources. The GET method retrieves data, POST creates new resources, PUT updates existing resources, and DELETE removes resources. Each method possesses unique characteristics in terms of safety, idempotence, and impact on server-side resources.

By comprehending these HTTP methods, developers can build robust and efficient web applications. They can effectively interact with APIs, retrieve information from servers using the GET method, create new resources using the POST method, update resources using the PUT method, and delete resources using the DELETE method. Proper utilization of these methods ensures smooth communication between clients and servers, enhancing the overall web browsing experience.

HTTP methods, such as GET, POST, PUT, and DELETE, along with the underlying HTTP protocols, enable seamless data transfer and resource manipulation on the web. They provide a standardized and structured approach to handling various types of requests and operations. Whether you are retrieving data, creating new resources, updating existing ones, or deleting specific resources, the understanding of these HTTP methods is crucial for effective web development and integration.

Cathy Berger

Cathy is a senior blogger and editor in chief at text-center.com.