When request comes from a client, it recieves two objects, Request and Response.
Request Header Information: Request contains a lot of header information. Some of them mentioned below:
1) Accept-It specifies the MIME type which clients accept.
2) Accept-Languages-It specifies the languages which clients recieve.
3) Accept-Encoding-It specifies the types of encodings that the browser knows how to handle. Values of gzip or compress are the two most common possibilities.
4) User-Agent-It gives information about client software(browser).
5) Cookie-It returns cookies to servers that previously sent them to the browser.
6) Content-Length-It is applicable to POST request and gives the size of POST data in bytes.
Response Object: It consist of three things-
Status Code
Header Information
Response Body which contains output.
Status Codes: Http status codes returned by server to the client. It is three digit integer value which gets specified as:
2**: Success
3**: Redirection
4**: Client Error
5**: Server Error
Response Header Information: Some of Http response header information are as follows:
1) Cache-control- It tells all caching mechanism from server to client whether they may cache this object.
2) Expires- It gives date and time after which the response is considered as expired.
3) Refresh- It is used to specify when response will get refreshed automatically.
4) Set-Cookie- It specifies a cookie associated with the page
5) Connection- It is used to indicate whether the server is willing to maintain as open connection to the client.