Activity 29: HTTP Methods | Aligan, Rhed N.

1. GET

   • Purpose: Retrieves data from the server.

   • How it works: You ask the server for information (like a list of universities), and the server sends it back without changing anything.

Example

• Imagine you have a store named “Rhed Store Appliances”. and you need to retrieve a list of all available products. you can do a request one of the API methods is

  GET/Appliances. This is the request, and the server will response of list of appliances in the store. Example

•   [
      { "id": 1, "name": "Refrigerator", "price": 10,999.00 },
      { "id": 2, "name": "Washing Machine", "price": 3,999,00}
    ]
  

The GET method fetches data from the server. It's like asking the server to "show me all the appliances in the store" without making any changes. You don’t send any data to the server for retrieval; it simply returns the requested information.

2. POST

   • Purpose: Sends data to the server to create a new resource.

   • How it works: You send data (like a new product or user information) to the server, and the server creates a new record with that data.

Example

• You already have a item in the store and you want to add new item for the customer demands, you just simplify a request using POST/Appliances.

• Request: POST/Appliances

    {
      "name": "LAPTOP ASUS",
      "price": 44,999.98.00
    }
    //This will be sending in the server together in the unique ID 
    //since we are adding new item
  

• Server Response confirms the new appliances was added in the appliances section.

•   {
      "id": 3,
      "name": "LAPTOP ASUS",
      "price": 44,999.98.00
    }
  

The POST method sends data to the server to create a new resource. In this case, a new appliance (LAPTOP ASUS) is added to the store’s inventory. You provide the data (name, price) in the request body, and the server creates a new entry.

3. PUT

   • Purpose: Updates an existing resource by replacing it with new data.

   • How it works: You send new data for a specific resource, and the server replaces the old data with the new data (e.g., changing the price of a product).

Example

• Imagine, now after your initial price in the store and store in the database, you want to update the current price or change the name you can do a PUT METHOD wherein you can change the data within the called section or components or specify section.

  Request: PUT /Appliances/1 (Product ID 1 refers to Laptop)

•   //current price{
      "name": "Laptop",
      "price": 44,999.98
    }
    //The Changes
      "name": "Laptop",
      "price": 39,599.00
  

Server Response

•   {
      "id": 1,
      "name": "Laptop",
      "price": 39,599.00
    }
  

The PUT method is used when you want to update an existing resource, replacing its current data. Here, the product’s price is updated, and all previous data (like the original price) is replaced with the new data you provide.

How it differs from POST?

• The PUT and POST methods are both used to modify resources in a REST API, but they differ in their purpose and behavior. PUT replaces a resource entirely and is idempotent. On the other hand, POST is used for creating new resources or appending data and is not idempotent​.

Idempotent is refers to the property of an operation where making multiple identical requests will have the same effect as making a single request.

4. DELETE

   • Purpose: Removes a resource from the server.

   • How it works: You tell the server to delete a specific resource (like a product or user), and the server removes it permanently.

Example

• Imagine as a customer you want to delete your order appliances in “Rhed Appliances Store”.

  Request: DELETE /appliances/8 (Product ID 8 refers to Refrigerator)

•   {
      "message": "Product deleted successfully."
    }
  

• Server Response

    {
      "message": "Product deleted successfully."
    }
  

The DELETE method is used when you want to remove a resource from the server. In this case, the Headphones are removed from the product list. The server confirms that the product was deleted.

5. PATCH

   • Purpose: Partially updates an existing resource.

   • How it works: You send only the data you want to update (like just changing the price of a product), and the server updates only that part without affecting the rest of the resource.

Example

• Imagine, instead of updating the entire product details, let's say you only want to update the price of the laptop without changing its name.

Request: PATCH /Appliances/23 (Product ID 23 refers to Laptop)

{
  "price": 799
}

Server Response

{
  "id": 1,
  "name": "Laptop",
  "price": 799
}

The PATCH method is used for partial updates. You only send the data you want to change—in this case, just the price. The other fields, like the name, stay unchanged.

Compared to PUT?

• PUT is used for full updates, requiring you to send the entire resource, which could be inefficient if only a few fields need to change. While PATCH is used for partial updates, making it ideal when you only need to update certain fields in a resource.

Conclusion

When you interact with a web service, you're essentially sending requests to a server to do certain tasks. The HTTP methods are like the tools in a toolbox, each one designed for a specific job. For instance, GET is like asking to see something, POST is like filling out a form to create something new, PUT is like making a complete update to an existing item, and PATCH is for making small tweaks. DELETE is when you decide to remove something altogether. These methods make it possible for web applications to run smoothly by giving clear instructions on how data should be managed, and when you understand them, you're equipped to build powerful and efficient APIs.