"nntplib" — NNTP プロトコルクライアント
***************************************

**ソースコード:** Lib/nntplib.py

======================================================================

This module defines the class "NNTP" which implements the client side
of the NNTP protocol.  It can be used to implement a news reader or
poster, or automated news processors.  For more information on NNTP
(Network News Transfer Protocol), see Internet **RFC 977**.

以下にこのモジュールの使い方の小さな例を二つ示します。ニュースグループ
に関する統計情報を列挙し、最新 10 件の記事を出力するには以下のようにし
ます:

   >>> s = NNTP('news.gmane.org')
   >>> resp, count, first, last, name = s.group('gmane.comp.python.committers')
   >>> print 'Group', name, 'has', count, 'articles, range', first, 'to', last
   Group gmane.comp.python.committers has 1071 articles, range 1 to 1071
   >>> resp, subs = s.xhdr('subject', first + '-' + last)
   >>> for id, sub in subs[-10:]: print id, sub
   ...
   1062 Re: Mercurial Status?
   1063 Re: [python-committers]  (Windows) buildbots on 3.x
   1064 Re: Mercurial Status?
   1065 Re: Mercurial Status?
   1066 Python 2.6.6 status
   1067 Commit Privileges for Ask Solem
   1068 Re: Commit Privileges for Ask Solem
   1069 Re: Commit Privileges for Ask Solem
   1070 Re: Commit Privileges for Ask Solem
   1071 2.6.6 rc 2
   >>> s.quit()
   '205 Bye!'

To post an article from a file (this assumes that the article has
valid headers, and that you have right to post on the particular
newsgroup):

   >>> s = NNTP('news.gmane.org')
   >>> f = open('articlefile')
   >>> s.post(f)
   '240 Article posted successfully.'
   >>> s.quit()
   '205 Bye!'

The module itself defines the following items:

class nntplib.NNTP(host[, port [, user[, password [, readermode] [, usenetrc]]]])

   Return a new instance of the "NNTP" class, representing a
   connection to the NNTP server running on host *host*, listening at
   port *port*.  The default *port* is 119.  If the optional *user*
   and *password* are provided, or if suitable credentials are present
   in "/.netrc" and the optional flag *usenetrc* is true (the
   default), the "AUTHINFO USER" and "AUTHINFO PASS" commands are used
   to identify and authenticate the user to the server. If the
   optional flag *readermode* is true, then a "mode reader" command is
   sent before authentication is performed.  Reader mode is sometimes
   necessary if you are connecting to an NNTP server on the local
   machine and intend to call reader-specific commands, such as
   "group".  If you get unexpected "NNTPPermanentError"s, you might
   need to set *readermode*. *readermode* defaults to "None".
   *usenetrc* defaults to "True".

   バージョン 2.4 で変更: *usenetrc* argument added.

exception nntplib.NNTPError

   Derived from the standard exception "Exception", this is the base
   class for all exceptions raised by the "nntplib" module.

exception nntplib.NNTPReplyError

   Exception raised when an unexpected reply is received from the
   server.  For backwards compatibility, the exception "error_reply"
   is equivalent to this class.

exception nntplib.NNTPTemporaryError

   Exception raised when an error code in the range 400–499 is
   received.  For backwards compatibility, the exception "error_temp"
   is equivalent to this class.

exception nntplib.NNTPPermanentError

   Exception raised when an error code in the range 500–599 is
   received.  For backwards compatibility, the exception "error_perm"
   is equivalent to this class.

exception nntplib.NNTPProtocolError

   Exception raised when a reply is received from the server that does
   not begin with a digit in the range 1–5.  For backwards
   compatibility, the exception "error_proto" is equivalent to this
   class.

exception nntplib.NNTPDataError

   Exception raised when there is some error in the response data.
   For backwards compatibility, the exception "error_data" is
   equivalent to this class.


NNTP オブジェクト
=================

NNTP instances have the following methods.  The *response* that is
returned as the first item in the return tuple of almost all methods
is the server’s response: a string beginning with a three-digit code.
If the server’s response indicates an error, the method raises one of
the above exceptions.

NNTP.getwelcome()

   サーバに最初に接続した際に送信される応答中のウェルカムメッセージを
   返します。(このメッセージには時に、ユーザにとって重要な免責事項や
   ヘルプ情報が入っています。)

NNTP.set_debuglevel(level)

   インスタンスのデバッグレベルを設定します。このメソッドは印字される
   デバッグ出力の量を制御します。標準では "0" に設定されていて、 これ
   はデバッグ出力を全く印字しません。 "1" はそこそこの量、一般に NNTP
   要求や応答あたり 1 行のデバッグ出力を生成します。値が "2" やそれ以
   上の場合、(メッセージテキストを含めて) NNTP 接続上で送受信された全
   ての内容を一行ごとにログ出力する、最大限のデバッグ出力を生成します
   。

NNTP.newgroups(date, time[, file])

   Send a "NEWGROUPS" command.  The *date* argument should be a string
   of the form "'yymmdd'" indicating the date, and *time* should be a
   string of the form "'hhmmss'" indicating the time.  Return a pair
   "(response, groups)" where *groups* is a list of group names that
   are new since the given date and time. If the *file* parameter is
   supplied, then the output of the  "NEWGROUPS" command is stored in
   a file.  If *file* is a string,  then the method will open a file
   object with that name, write to it  then close it.  If *file* is a
   file object, then it will start calling "write()" on it to store
   the lines of the command output. If *file* is supplied, then the
   returned *list* is an empty list.

NNTP.newnews(group, date, time[, file])

   Send a "NEWNEWS" command.  Here, *group* is a group name or "'*'",
   and *date* and *time* have the same meaning as for "newgroups()".
   Return a pair "(response, articles)" where *articles* is a list of
   message ids. If the *file* parameter is supplied, then the output
   of the  "NEWNEWS" command is stored in a file.  If *file* is a
   string,  then the method will open a file object with that name,
   write to it  then close it.  If *file* is a file object, then it
   will start calling "write()" on it to store the lines of the
   command output. If *file* is supplied, then the returned *list* is
   an empty list.

NNTP.list([file])

   Send a "LIST" command.  Return a pair "(response, list)" where
   *list* is a list of tuples.  Each tuple has the form "(group, last,
   first, flag)", where *group* is a group name, *last* and *first*
   are the last and first article numbers (as strings), and *flag* is
   "'y'" if posting is allowed, "'n'" if not, and "'m'" if the
   newsgroup is moderated.  (Note the ordering: *last*, *first*.) If
   the *file* parameter is supplied, then the output of the  "LIST"
   command is stored in a file.  If *file* is a string,  then the
   method will open a file object with that name, write to it  then
   close it.  If *file* is a file object, then it will start calling
   "write()" on it to store the lines of the command output. If *file*
   is supplied, then the returned *list* is an empty list.

NNTP.descriptions(grouppattern)

   Send a "LIST NEWSGROUPS" command, where *grouppattern* is a wildmat
   string as specified in RFC2980 (it’s essentially the same as DOS or
   UNIX shell wildcard strings).  Return a pair "(response, list)",
   where *list* is a list of tuples containing "(name, title)".

   バージョン 2.4 で追加.

NNTP.description(group)

   単一のグループ *group* から説明文字列を取り出します。 (『group』 が
   実際には wildmat 文字列で) 複数のグループがマッチした場合、 最初に
   マッチしたものを返します。何もマッチしなければ空文字列を返します。

   このメソッドはサーバからの応答コードを省略します。応答コードが必要
   なら、 "descriptions()" を使ってください。

   バージョン 2.4 で追加.

NNTP.group(name)

   Send a "GROUP" command, where *name* is the group name. Return a
   tuple "(response, count, first, last, name)" where *count* is the
   (estimated) number of articles in the group, *first* is the first
   article number in the group, *last* is the last article number in
   the group, and *name* is the group name. The numbers are returned
   as strings.

NNTP.help([file])

   Send a "HELP" command.  Return a pair "(response, list)" where
   *list* is a list of help strings. If the *file* parameter is
   supplied, then the output of the  "HELP" command is stored in a
   file.  If *file* is a string,  then the method will open a file
   object with that name, write to it  then close it.  If *file* is a
   file object, then it will start calling "write()" on it to store
   the lines of the command output. If *file* is supplied, then the
   returned *list* is an empty list.

NNTP.stat(id)

   Send a "STAT" command, where *id* is the message id (enclosed in
   "'<'" and "'>'") or an article number (as a string). Return a
   triple "(response, number, id)" where *number* is the article
   number (as a string) and *id* is the message id  (enclosed in "'<'"
   and "'>'").

NNTP.next()

   "NEXT" 命令を送信します。 "stat()" のような応答を返します。

NNTP.last()

   "LAST" 命令を送信します。 "stat()" のような応答を返します。

NNTP.head(id)

   Send a "HEAD" command, where *id* has the same meaning as for
   "stat()". Return a tuple "(response, number, id, list)" where the
   first three are the same as for "stat()", and *list* is a list of
   the article’s headers (an uninterpreted list of lines, without
   trailing newlines).

NNTP.body(id[, file])

   Send a "BODY" command, where *id* has the same meaning as for
   "stat()". If the *file* parameter is supplied, then the body is
   stored in a file.  If *file* is a string, then the method will open
   a file object with that name, write to it then close it. If *file*
   is a file object, then it will start calling "write()" on it to
   store the lines of the body. Return as for "head()".  If *file* is
   supplied, then the returned *list* is an empty list.

NNTP.article(id)

   Send an "ARTICLE" command, where *id* has the same meaning as for
   "stat()".  Return as for "head()".

NNTP.slave()

   "SLAVE" 命令を送信します。サーバの *response* を返します。

NNTP.xhdr(header, string[, file])

   Send an "XHDR" command.  This command is not defined in the RFC but
   is a common extension.  The *header* argument is a header keyword,
   e.g. "'subject'".  The *string* argument should have the form
   "'first-last'" where *first* and *last* are the first and last
   article numbers to search. Return a pair "(response, list)", where
   *list* is a list of pairs "(id, text)", where *id* is an article
   number (as a string) and *text* is the text of the requested header
   for that article. If the *file* parameter is supplied, then the
   output of the  "XHDR" command is stored in a file.  If *file* is a
   string, then the method will open a file object with that name,
   write to it  then close it.  If *file* is a file object, then it
   will start calling "write()" on it to store the lines of the
   command output. If *file* is supplied, then the returned *list* is
   an empty list.

NNTP.post(file)

   Post an article using the "POST" command.  The *file* argument is
   an open file object which is read until EOF using its "readline()"
   method.  It should be a well-formed news article, including the
   required headers.  The "post()" method automatically escapes lines
   beginning with ".".

NNTP.ihave(id, file)

   Send an "IHAVE" command. *id* is a message id (enclosed in  "'<'"
   and "'>'"). If the response is not an error, treat *file* exactly
   as for the "post()" method.

NNTP.date()

   Return a triple "(response, date, time)", containing the current
   date and time in a form suitable for the "newnews()" and
   "newgroups()" methods. This is an optional NNTP extension, and may
   not be supported by all servers.

NNTP.xgtitle(name[, file])

   Process an "XGTITLE" command, returning a pair "(response, list)",
   where *list* is a list of tuples containing "(name, title)". If the
   *file* parameter is supplied, then the output of the  "XGTITLE"
   command is stored in a file. If *file* is a string,  then the
   method will open a file object with that name, write to it  then
   close it.  If *file* is a file object, then it will start calling
   "write()" on it to store the lines of the command output. If *file*
   is supplied, then the returned *list* is an empty list. This is an
   optional NNTP extension, and may not be supported by all servers.

   RFC2980 says 「It is suggested that this extension be deprecated」.
   Use "descriptions()" or "description()" instead.

NNTP.xover(start, end[, file])

   Return a pair "(resp, list)".  *list* is a list of tuples, one for
   each article in the range delimited by the *start* and *end*
   article numbers.  Each tuple is of the form "(article number,
   subject, poster, date, id, references, size, lines)". If the *file*
   parameter is supplied, then the output of the "XOVER" command is
   stored in a file.  If *file* is a string,  then the method will
   open a file object with that name, write to it  then close it.  If
   *file* is a file object, then it will start calling "write()" on it
   to store the lines of the command output. If *file* is supplied,
   then the returned *list* is an empty list. This is an optional NNTP
   extension, and may not be supported by all servers.

NNTP.xpath(id)

   Return a pair "(resp, path)", where *path* is the directory path to
   the article with message ID *id*.  This is an optional NNTP
   extension, and may not be supported by all servers.

NNTP.quit()

   "QUIT" 命令を送信し、接続を閉じます。このメソッドを呼び出した後は、
   NTTP オブジェクトの他のいかなるメソッドも呼び出してはいけません。
