Notes on HTTP

See also

• HTTP Made Really Easy: A Practical Guide to Writing Clients and Servers
• Google "simple http client"
• Web client (dir) from Hall's Core Servlets

Standards
The Internet Engineering Task Force (IETF)
RFC 2068 HTTP/1.1 Proposed Standard (text)
RFC 7540 Hypertext Transfer Protocol Version 2 (HTTP/2)

HTTP/2: "This specification is an alternative to, but does not obsolete, the HTTP/1.1 message syntax. HTTP's existing semantics remain unchanged."

W3C: HTTP - Hypertext Transfer Protocol
www.w3.org/Protocols

Hypertext Transfer Protocol -- HTTP/1.1
www.freesoft.org/CIE/RFC/2068/

HTML version hosted by www.freesoft.org

Table of Contents outline (original version):

1. Introduction
2. Notational Conventions and Generic Grammar
3. Protocol Parameters
4. HTTP Message
5. Request
6. Response
7. Entity
8. Connections
9. Method Definitions
10. Status Code Definitions
11. Access Authentication
12. Content Negotiation
13. Caching in HTTP
14. Header Field Definitions
15. Security Considerations
16. Acknowledgments
17. References
18. Authors' Addresses
19. Appendices

1.2 Requirements
must, should, may

1.3 Terminology
connection, message, request, response, resource, entity, representation, content negotiation, variant, client, user agent, server, origin server, proxy, gateway, tunnel, cache, cacheable, first-hand, explicit expiration time, heuristic expiration time, age, freshness lifetime, fresh, stale, semantically transparent, validator

1.4 Overall Operation

2.2 Basic Rules

4.1 Message Types

4.2 Message Headers

Web client (dir) from Hall's Core Servlets. See

• WebClient.java: public void run()
• HttpClient.java: protected void handleConnection(Socket uriSocket)
• NetworkClient.java: public void connect(), protected void handleConnection(Socket client)

5 Request

5.1 Request-Line
E.g.: GET http://www.w3.org/pub/WWW/TheProject.html HTTP/1.1
E.g.: OPTIONS * HTTP/1.1     Pay attention to the response!
E.g.: NOKNOWN

5.3 Request Header Fields
TO: www.mscs.mu.edu

GET /~georgec/OpSys/index.html HTTP/1.1

6 Response

6.1 Status-Line
Status-Line = HTTP-Version SP Status-Code SP Reason-Phrase CRLF

6.1.1 Status Code and Reason Phrase

6.2 Response Header Fields

7.1 Entity Header Fields

7.2 Entity Body