Net::NNTP - NNTP Client class
- use Net::NNTP;
- $nntp = Net::NNTP->new("some.host.name");
- $nntp->quit;
- # start with SSL, e.g. nntps
- $nntp = Net::NNTP->new("some.host.name", SSL => 1);
- # start with plain and upgrade to SSL
- $nntp = Net::NNTP->new("some.host.name");
- $nntp->starttls;
Net::NNTP
is a class implementing a simple NNTP client in Perl as described
in RFC977 and RFC4642.
With IO::Socket::SSL installed it also provides support for implicit and
explicit TLS encryption, i.e. NNTPS or NNTP+STARTTLS.
The Net::NNTP class is a subclass of Net::Cmd and (depending on avaibility) of IO::Socket::IP, IO::Socket::INET6 or IO::Socket::INET.
This is the constructor for a new Net::NNTP object. HOST
is the
name of the remote host to which a NNTP connection is required. If not
given then it may be passed as the Host
option described below. If no host is passed
then two environment variables are checked, first NNTPSERVER
then
NEWSHOST
, then Net::Config
is checked, and if a host is not found
then news
is used.
OPTIONS
are passed in a hash like fashion, using key and value pairs.
Possible options are:
Host - NNTP host to connect to. It may be a single scalar, as defined for
the PeerAddr
option in IO::Socket::INET, or a reference to
an array with hosts to try in turn. The host method will return the value
which was used to connect to the host.
Port - port to connect to. Default - 119 for plain NNTP and 563 for immediate SSL (nntps).
SSL - If the connection should be done from start with SSL, contrary to later
upgrade with starttls
.
You can use SSL arguments as documented in IO::Socket::SSL, but it will
usually use the right arguments already.
Timeout - Maximum time, in seconds, to wait for a response from the NNTP server, a value of zero will cause all IO operations to block. (default: 120)
Debug - Enable the printing of debugging information to STDERR
Reader - If the remote server is INN then initially the connection
will be to innd, by default Net::NNTP
will issue a MODE READER
command
so that the remote server becomes nnrpd. If the Reader
option is given
with a value of zero, then this command will not be sent and the
connection will be left talking to innd.
LocalAddr and LocalPort - These parameters are passed directly to IO::Socket to allow binding the socket to a specific local address and port.
Domain - This parameter is passed directly to IO::Socket and makes it possible to enforce IPv4 connections even if IO::Socket::IP is used as super class. Alternatively Family can be used.
Unless otherwise stated all methods return either a true or false value, with true meaning that the operation was a success. When a method states that it returns a value, failure will be returned as undef or an empty list.
Net::NNTP
inherits from Net::Cmd
so methods defined in Net::Cmd
may
be used to send commands to the remote NNTP server in addition to the methods
documented here.
Returns the value used by the constructor, and passed to IO::Socket::INET, to connect to the host.
Upgrade existing plain connection to SSL.
Any arguments necessary for SSL must be given in new
already.
Retrieve the header, a blank line, then the body (text) of the specified article.
If FH
is specified then it is expected to be a valid filehandle
and the result will be printed to it, on success a true value will be
returned. If FH
is not specified then the return value, on success,
will be a reference to an array containing the article requested, each
entry in the array will contain one line of the article.
If no arguments are passed then the current article in the currently selected newsgroup is fetched.
MSGNUM
is a numeric id of an article in the current newsgroup, and
will change the current article pointer. MSGID
is the message id of
an article as shown in that article's header. It is anticipated that the
client will obtain the MSGID
from a list provided by the newnews
command, from references contained within another article, or from the
message-id provided in the response to some other commands.
If there is an error then undef will be returned.
Like article
but only fetches the body of the article.
Like article
but only fetches the headers for the article.
These are similar to article(), body() and head(), but rather than returning the requested data directly, they return a tied filehandle from which to read the article.
The nntpstat
command is similar to the article
command except that no
text is returned. When selecting by message number within a group,
the nntpstat
command serves to set the "current article pointer" without
sending text.
Using the nntpstat
command to
select by message-id is valid but of questionable value, since a
selection by message-id does not alter the "current article pointer".
Returns the message-id of the "current article".
Set and/or get the current group. If GROUP
is not given then information
is returned on the current group.
In a scalar context it returns the group name.
In an array context the return value is a list containing, the number of articles in the group, the number of the first article, the number of the last article and the group name.
Request help text (a short summary of commands that are understood by this implementation) from the server. Returns the text or undef upon failure.
The ihave
command informs the server that the client has an article
whose id is MSGID
. If the server desires a copy of that
article and MESSAGE
has been given then it will be sent.
Returns true if the server desires the article and MESSAGE
was
successfully sent, if specified.
If MESSAGE
is not specified then the message must be sent using the
datasend
and dataend
methods from Net::Cmd
MESSAGE
can be either an array of lines or a reference to an array
and must be encoded by the caller to octets of whatever encoding is required,
e.g. by using the Encode module's encode()
function.
Set the "current article pointer" to the previous article in the current newsgroup.
Returns the message-id of the article.
Returns the date on the remote server. This date will be in a UNIX time format (seconds since 1970)
postok
will return true if the servers initial response indicated
that it will allow posting.
Authenticates to the server (using the original AUTHINFO USER / AUTHINFO PASS form, defined in RFC2980) using the supplied username and password. Please note that the password is sent in clear text to the server. This command should not be used with valuable passwords unless the connection to the server is somehow protected.
Authenticates to the server (using the proposed NNTP V2 AUTHINFO SIMPLE form, defined and deprecated in RFC2980) using the supplied username and password. As with authinfo the password is sent in clear text.
Obtain information about all the active newsgroups. The results is a reference to a hash where the key is a group name and each value is a reference to an array. The elements in this array are:- the last article number in the group, the first article number in the group and any information flags about the group.
SINCE
is a time value and DISTRIBUTIONS
is either a distribution
pattern or a reference to a list of distribution patterns.
The result is the same as list
, but the
groups return will be limited to those created after SINCE
and, if
specified, in one of the distribution areas in DISTRIBUTIONS
.
SINCE
is a time value. GROUPS
is either a group pattern or a reference
to a list of group patterns. DISTRIBUTIONS
is either a distribution
pattern or a reference to a list of distribution patterns.
Returns a reference to a list which contains the message-ids of all news posted
after SINCE
, that are in a groups which matched GROUPS
and a
distribution which matches DISTRIBUTIONS
.
Set the "current article pointer" to the next article in the current newsgroup.
Returns the message-id of the article.
Post a new article to the news server. If MESSAGE
is specified and posting
is allowed then the message will be sent.
If MESSAGE
is not specified then the message must be sent using the
datasend
and dataend
methods from Net::Cmd
MESSAGE
can be either an array of lines or a reference to an array
and must be encoded by the caller to octets of whatever encoding is required,
e.g. by using the Encode module's encode()
function.
The message, either sent via datasend
or as the MESSAGE
parameter, must be in the format as described by RFC822 and must
contain From:, Newsgroups: and Subject: headers.
Post a new article to the news server using a tied filehandle. If posting is allowed, this method will return a tied filehandle that you can print() the contents of the article to be posted. You must explicitly close() the filehandle when you are finished posting the article, and the return value from the close() call will indicate whether the message was successfully posted.
Tell the remote server that I am not a user client, but probably another news server.
Quit the remote server and close the socket connection.
Returns whether we can use IPv6.
Returns whether we can use SSL.
These methods use commands that are not part of the RFC977 documentation. Some servers may not support all of them.
Returns a reference to a hash where the keys are all the group names which
match PATTERN
, or all of the groups if no pattern is specified, and
each value contains the description text for the group.
Returns a reference to a hash where the keys are all the possible distribution names and the values are the distribution descriptions.
Returns a reference to an array where each element, itself an array reference, consists of the three fields of a line of the distrib.pats list maintained by some NNTP servers, namely: a weight, a wildmat and a value which the client may use to construct a Distribution header.
Returns a reference to a list which contains a list of groups which are recommended for a new user to subscribe to.
Returns a reference to an array which contain the names of the fields returned
by xover
.
Returns a reference to a hash where the keys are the group names and each value is a reference to an array containing the time the groups was created and an identifier, possibly an Email address, of the creator.
Similar to list
but only active groups that match the pattern are returned.
PATTERN
can be a group pattern.
Returns a reference to a hash where the keys are all the group names which
match PATTERN
and each value is the description text for the group.
Obtain the header field HEADER
for all the messages specified.
The return value will be a reference to a hash where the keys are the message numbers and each value contains the text of the requested header for that message.
The return value will be a reference to a hash where the keys are the message numbers and each value contains a reference to an array which contains the overview fields for that message.
The names of the fields can be obtained by calling overview_fmt
.
Returns the path name to the file on the server which contains the specified message.
The result is the same as xhdr
except the is will be restricted to
headers where the text of the header matches PATTERN
The XROVER command returns reference information for the article(s) specified.
Returns a reference to a HASH where the keys are the message numbers and the values are the References: lines from the articles
Returns a reference to a list of all the active messages in GROUP
, or
the current group if GROUP
is not specified.
Tell the server that you are a reader and not another server.
This is required by some servers. For example if you are connecting to an INN server and you have transfer permission your connection will be connected to the transfer daemon, not the NNTP daemon. Issuing this command will cause the transfer daemon to hand over control to the NNTP daemon.
Some servers do not understand this command, but issuing it and ignoring the response is harmless.
The following NNTP command are unsupported by the package, and there are no plans to do so.
- AUTHINFO GENERIC
- XTHREAD
- XSEARCH
- XINDEX
MESSAGE-SPEC
is either a single message-id, a single message number, or
a reference to a list of two message numbers.
If MESSAGE-SPEC
is a reference to a list of two message numbers and the
second number in a range is less than or equal to the first then the range
represents all messages in the group after the first message number.
NOTE For compatibility reasons only with earlier versions of Net::NNTP a message spec can be passed as a list of two numbers, this is deprecated and a reference to the list should now be passed
The NNTP
protocol uses the WILDMAT
format for patterns.
The WILDMAT format was first developed by Rich Salz based on
the format used in the UNIX "find" command to articulate
file names. It was developed to provide a uniform mechanism
for matching patterns in the same manner that the UNIX shell
matches filenames.
Patterns are implicitly anchored at the beginning and end of each string when testing for a match.
There are five pattern matching operations other than a strict one-to-one match between the pattern and the source to be checked for a match.
The first is an asterisk *
to match any sequence of zero or more
characters.
The second is a question mark ? to match any single character. The
third specifies a specific set of characters.
The set is specified as a list of characters, or as a range of characters
where the beginning and end of the range are separated by a minus (or dash)
character, or as any combination of lists and ranges. The dash can
also be included in the set as a character it if is the beginning
or end of the set. This set is enclosed in square brackets. The
close square bracket ] may be used in a set if it is the first
character in the set.
The fourth operation is the same as the
logical not of the third operation and is specified the same
way as the third with the addition of a caret character ^ at
the beginning of the test string just inside the open square
bracket.
The final operation uses the backslash character to
invalidate the special meaning of an open square bracket [,
the asterisk, backslash or the question mark. Two backslashes in
sequence will result in the evaluation of the backslash as a
character with no special meaning.
[^]-]
matches any single character other than a close square bracket or a minus sign/dash.
*bdc
matches any string that ends with the string "bdc" including the string "bdc" (without quotes).
[0-9a-zA-Z]
matches any single printable alphanumeric ASCII character.
a??d
matches any four character string which begins with a and ends with d.
Graham Barr <[email protected]>
Steve Hay <[email protected]> is now maintaining libnet as of version 1.22_02
Versions up to 2.24_1 Copyright (c) 1995-1997 Graham Barr. All rights reserved. Changes in Version 2.25 onwards Copyright (C) 2013-2015 Steve Hay. All rights reserved.
This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself, i.e. under the terms of either the GNU General Public License or the Artistic License, as specified in the LICENCE file.