GET and POST Methods in PHP: A Guide to Best Practices

Communication between a client (usually a web browser) and a server is handled by HTTP methods. GET and POST methods are two of the most commonly used for client-server communication in PHP.

GET is typically used to retrieve data while POST is used to create or update data. However, you can use both methods interchangeably but it depends on your needs.

This blog post explains when to use the GET and POST methods in PHP. Describes best practices for using the GET and POST methods. 

When to use GET?

The GET method serves as a fundamental tool in web development, allowing users to retrieve information from servers. It plays a crucial role in various scenarios, ensuring efficient and seamless interactions between clients and servers.

Here are some key situations where implementing the GET method is highly appropriate:

1. Retrieving specific resources: When you aim to acquire a particular resource or a collection of resources from a server, employing the GET method is the recommended approach. For instance, you can utilize GET to fetch comprehensive details regarding a user profile, retrieve a comprehensive list of products from an online store, or obtain the contents of a specific blog post.

2. Reading data: GET is well-suited for reading data from a server without altering it. If you need to access information such as weather updates, stock prices, or news articles, the GET method enables you to retrieve the relevant data reliably and effectively.

3. Stateless operations: GET requests are designed to be idempotent, meaning that executing multiple identical requests should yield the same outcome as a single request. Consequently, GET is particularly suitable for performing stateless operations that do not modify server resources. Examples of such operations include retrieving the current time from a server or fetching a list of available categories in an e-commerce application.

4. Bookmarking or sharing resources: GET requests offer the advantage of easy bookmarking and sharing, as all the necessary information is contained within the URL. This convenient feature allows users to revisit specific resources by simply clicking on a bookmark or sharing the URL with others. Whether it’s an intriguing article, a product page, or any other resource, GET enables straightforward access and distribution.

5. Caching: Browsers and intermediate caching servers can cache GET requests, leading to improved performance and reduced server load. This caching mechanism proves highly beneficial, especially when the requested resource remains relatively static and undergoes infrequent changes. By allowing browsers and caching servers to serve the cached version of a GET request, the overall responsiveness and efficiency of the application can be significantly enhanced.

When to use POST?

The POST method is another essential tool in web development, serving a distinct purpose compared to the GET method. Here are some key situations where implementing the POST method is highly appropriate:

1. Creating new resources: POST is commonly employed when you need to create new resources on the server. For example, to create a new blog post in a web application, a user can submit a form. The data they enter in the form is sent to the server using a POST request. The server then processes the request and creates the new blog post.

2. Submitting data: POST is suitable for sending data to the server for processing or storage. This can include submitting a contact form, making a payment, or uploading a file. POST requests are typically used when the data being sent is sensitive or confidential, as the request body is not directly visible in the URL.

3. Modifying server resources: Unlike the idempotent nature of GET requests, POST requests are not idempotent. With each initiation of a POST request, the server has the potential to undergo changes. Therefore, POST is appropriate when you need to modify or update server resources. For instance, updating a user’s profile information, adding items to a shopping cart, or changing the state of an object in a web application.

4. Handling large or complex data: POST allows for sending large amounts of data compared to GET, as the data is transmitted in the request body rather than appended to the URL. This makes POST suitable for scenarios where you need to transmit large files, such as uploading images or videos.

5. Processing sensitive information: When dealing with sensitive information, such as passwords or personal data, it is recommended to use POST over GET. As mentioned earlier, the request body in a POST request is not directly visible in the URL, providing an additional layer of security.

Best Practices for Using the GET Method.

Best practices for using the GET method to ensure that your API is well-designed and easy to use.

• Use nouns instead of verbs in URLs. It makes the API more self-documented and makes it clear what the endpoint is used for.
  For example, use /articles instead of /articles/get.

• Only use GET to retrieve data. The GET method should not be used to modify or delete data. If you need to modify or delete data, the recommended HTTP methods are POST, PUT, and DELETE rather than GET.

• Use query parameters to filter and sort data. Query parameters allow you to filter and sort the data returned from a GET request. This can be helpful for users who want to narrow down the results of their query.

• Use HATEOAS to provide links to related resources. HATEOAS stands for Hypermedia As The Engine Of Application State, and it is a way of designing APIs that makes it easy for users to navigate between related resources. When using HATEOAS, the API should return links to related resources in the response body. This allows users to easily discover and explore the data that is available.

• Use HTTP status codes to indicate the success or failure of a request. HTTP status codes are used to indicate the success or failure of HTTP requests. The following status codes should be used when using the GET method.
  • 200 OK: The request was successful and data was returned.
  • 400 Bad Request: The request was malformed or invalid.
  • 401 Unauthorized: The user is not authorized to access the resource.
  • 403 Forbidden: The user is authorized to access the resource, but they do not have the necessary permissions.
  • 404 Not Found: The resource was not found.

Additional Expert tips.

• Use the Accept header to indicate the format of the data that you want to receive. This can help improve performance, as the server can avoid sending data in a format that the client cannot understand.

• Use the Cache-Control header to control how long the response should be cached by the client. This can help improve performance by reducing the number of requests that need to be made to the server.

• Use the ETag header to provide a unique identifier for the resource. This can be used to avoid making unnecessary requests to the server, as the client can compare the ETag header with the one that is stored in the cache.

Best Practices for Using the POST Method.

Best practices for using the POST method to ensure that your API is well-designed and easy to use:

• Use nouns instead of verbs in URLs. This makes the API more self-documenting and makes it clear what the endpoint is used for. For example, use /articles instead of /articles/create.

• Use the Content-Type header to indicate the format of the data that you are sending. It plays an important role in enabling the server to correctly interpret the data being sent. For example, if you are sending JSON data, you would use the Content-Type: application/json header.

• Use the Accept header to indicate the format of the data that you want to receive. This can help improve performance, as the server can avoid sending data in a format that the client cannot understand.

• Use HTTP status codes to indicate the success or failure of a request. HTTP status codes are used to indicate the success or failure of an HTTP request. When using the POST method, you should use the following status codes:
  • 201 Created: The request was successful and the resource was created.
  • 400 Bad Request: The request was malformed or invalid.
  • 401 Unauthorized: The user is not authorized to create the resource.
  • 403 Forbidden: The user is authorized to create the resource, but they do not have the necessary permissions.
  • 409 Conflict: The resource already exists.

Additional Expert tips.

• Use the X-CSRF-Token header to protect against cross-site request forgery (CSRF) attacks.

• Use the Cache-Control header to control how long the response should be cached by the client. This can help improve performance by reducing the number of requests that need to be made to the server.

• Use the ETag header to provide a unique identifier for the resource. This can be used to avoid making unnecessary requests to the server, as the client can compare the ETag header with the one that is stored in the cache.

Conclusion.

Understanding when to use GET and POST is essential for designing robust and effective web applications. By utilizing these methods appropriately, developers can create user-friendly experiences, ensure data security, and optimize performance.

It is important to consider the specific needs of each situation and follow best practices to achieve the desired functionality and maintain application integrity.

Ultimately, by leveraging the power of GET and POST methods effectively, web developers can build interactive and dynamic applications. It enables users to retrieve information, submit data, and interact seamlessly with servers. So they can enhance the overall user experience on the web.