trivial-nntp

https://github.com/stacksmith/trivial-nntp.git


    git clone 'https://github.com/stacksmith/trivial-nntp.git'
      

      

(ql:quickload :trivial-nntp)

★1

trivial-nntp

Common lisp tools for connecting to and crawling around NNTP servers. It uses usocket.

This is a minimalistic effort; however watch this:

 CL-USER> 
 CL-USER> (tnntp:send-command "HELP")
 1
 "100 Legal commands^M"
 CL-USER> (tnntp:read-list)
 "Report problems to <usenet@fleegle.mixmin.net>.^M"
 "  XPAT header message-ID|range pattern [pattern ...]^M" "  XOVER [range]^M"
 "  XHDR header [message-ID|range]^M" "  XGTITLE [wildmat]^M"
 "  STAT [message-ID|number]^M" "  STARTTLS^M" "  QUIT^M" "  POST^M"
 ...
 "  ARTICLE [message-ID|number]^M")
 CL-USER> (tnntp:disconnect)
2
"205 Bye!^M"
CL-USER>

At the core, the server structure (see ‘tnntp.lisp’) contains information about the URL, port, authentication and connection state to a server. The system will transparently reconnect and restore current group on a connection should the server close the connection.

Multiple server connections are supported (via arrays of sockets and groups for each server). A socket is selected by specifying server and socket index. For defaults, *server* and socket index 0 are used; an open nntp server ‘news.mixmin.net’ is defaulted to.

Commands are sent with (send-command “commandstring” :expecting 2 ) The expecting parameter, if specified, makes sure that the response in in 200-299 range (only first digit is checked). For commands with an additional parameter such as “GROUP groupname” the :also parameter avoids building command strings: (send-command “GROUP” :also groupname)

Responses are read with

(read-unit) - read one line
(read-list) - read lines terminated by “.^M” into a list

Lines are returned unprocessed, with control-M character. Rationale: you will probably parse the lines anyway, so there is little reason to worry about that.

WORKFLOW

Create a server structure with your server url, port and authentication info.
(send-command …) “MODE READER” is a good start. If you send commands that return data, make sure to read everything up to and including the termination line containing a single dot. See (read-list) for details. If you don't you will get out of sync and send-command will not get a good response line.
(disconnect) when done – it sends “QUIT” and kills the sockets
Write an news transport, a reader, a downloader, or anything that you are discouraged to do in this article

A SIMPLE EXAMPLE

(load-groups)
(search-groups "book")

Search the grouplist for anything containing the word ‘book’; regex expressions allowed!

References: * * USOCKET API * RFC 977: Network News Transfer Protocol (1986) * RFC 1036: Standard for Interchange of USENET Messages (1987) * Don't Write a Newsreader (1995)