Understanding HTTP

• REST APIs embraces all aspects of HTTP (Hyper Text Transfer Protocol)
  
• The Request sent by the client can be summarized as

Request = <Method> <Request-URI> <HTTP-Version>

• Example: GET /todos/1 HTTP/2
• The Response from the Server can be summarized as

Response = <HTTP-Version> <Status Code> <Reason-Phrase>

• Example: HTTP/2 200

HTTP Methods

• We will be using four most common HTTP Methods
  • GET: This method requests a representation of specified Resource. Requests using GET should only retrieve data. (Retrieve)
  • PUT: This method replaces the current representation of the target resource (Update)
  • POST: This method submits an entity to the specified resource for creation. (Create)
  • DELETE: This method creates a request to DELETE some resource (Delete)
• There are other HTTP Methods
  • HEAD
  • OPTIONS
  • PATCH
  • CONNECT
  • TRACE

HTTP Response Status Codes

• Status Code By Category

| Category | Description |
| ——- | ———– |
| 1xx | Information |
| 2xx | Success: Indicates, the client request was accepted succesfully |
| 3xx | Redirection: Indicates that the client must take some additional actions to complete their request|
| 4xx | Client Error: This category of error status codes points the finger at clients |
| 5xx | Server Error: The server takes responsibility for these error status |

Activity 1: Lets create a HTTP GET Request from PostMan

• Creating a HTTP Request to fake rest api
  
  
  
  
  
  
• Selecting other HTTP Methods