Cheat Sheet #day10 - HTTP Methods

HTTP Methods Cheat Sheet

HTTP methods define the action to be performed for a given resource in a web application. Here's a quick reference to the most commonly used HTTP methods and their typical use cases.

GET

• Purpose: Retrieve data from a server.
• Characteristics:
  • Request data is sent in the URL.
  • Should be idempotent (same request can be made multiple times without changing the result).
  • Safe operation (does not modify resources).
• Example:

  GET /api/users HTTP/1.1
  Host: cloudtuned.com
  

POST

• Purpose: Submit data to a server to create a new resource.
• Characteristics:
  • Data is sent in the request body.
  • Not idempotent (submitting the same data multiple times may result in multiple resources being created).

• Example:

  POST /api/users HTTP/1.1
  Host: cloudtuned.com
  Content-Type: application/json
  
  {
    "name": "John Doe",
    "email": "john.doe@cloudtuned.com"
  }
  

PUT

• Purpose: Update an existing resource or create a new one if it does not exist.
• Characteristics:
  • Data is sent in the request body.
  • Idempotent (multiple identical requests will result in the same resource state).

• Example:

  PUT /api/users/1 HTTP/1.1
  Host: cloudtuned.com
  Content-Type: application/json
  
  {
    "name": "John Doe",
    "email": "john.doe@cloudtuned.com"
  }
  

PATCH

• Purpose: Apply partial modifications to a resource.
• Characteristics:
  • Data is sent in the request body.
  • Not necessarily idempotent.

• Example:

  PATCH /api/users/1 HTTP/1.1
  Host: cloudtuned.com
  Content-Type: application/json
  
  {
    "email": "john.new@cloudtuned.com"
  }
  

DELETE

• Purpose: Remove a resource from the server.
• Characteristics:
  • Idempotent (multiple identical delete requests will have the same effect).
• Example:

  DELETE /api/users/1 HTTP/1.1
  Host: cloudtuned.com
  

HEAD

• Purpose: Retrieve the headers for a resource, without the response body.
• Characteristics:
  • Used for checking what a GET request will return before making the actual request.
  • Idempotent and safe.
• Example:

  HEAD /api/users HTTP/1.1
  Host: cloudtuned.com
  

OPTIONS

• Purpose: Describe the communication options for the target resource.
• Characteristics:
  • Used for CORS preflight requests.
  • Safe and idempotent.
• Example:

  OPTIONS /api/users HTTP/1.1
  Host: cloudtuned.com
  

TRACE

• Purpose: Perform a message loop-back test along the path to the target resource.
• Characteristics:
  • Used mainly for diagnostic purposes.
  • Safe and idempotent.
• Example:

  TRACE /api/users HTTP/1.1
  Host: cloudtuned.com
  

CONNECT

• Purpose: Establish a tunnel to the server identified by the target resource.
• Characteristics:
  • Used mainly for SSL tunneling.
• Example:

  CONNECT cloudtuned.com:443 HTTP/1.1
  Host: cloudtuned.com
  

Summary

• Safe Methods: GET, HEAD, OPTIONS, TRACE
• Idempotent Methods: GET, PUT, DELETE, HEAD, OPTIONS, TRACE
• Common Use Cases:
  • GET: Fetching data, reading resources.
  • POST: Creating new resources, submitting forms.
  • PUT: Updating or replacing resources.
  • PATCH: Partially updating resources.
  • DELETE: Removing resources.

Understanding these HTTP methods and their appropriate use cases is crucial for designing RESTful APIs and handling web requests effectively.