NAME¶
News::Article - Object for handling Usenet articles in mail or news form.
SYNOPSIS¶
use News::Article;
See below for functions available.
DESCRIPTION¶
An object for representing a Usenet article (or a mail message). Primarily
written for use with mail2news and/or moderation programs. (Not really
intended for transit use.)
USAGE¶
use News::Article;
Article exports nothing.
Article objects must be created with the
new method.
Article Methods¶
- new ()
- new ( SOURCE [,MAXSIZE [,MAXHEADS]] )
- Use this to create a new Article object. Makes an empty article if no
parameters are specified, otherwise reads in an article from
"SOURCE" as for "read".
- clone ()
- Create a new Article as an exact clone of the current one. Returns a ref
to the new object.
- envelope ( [SENDER] )
- If "SENDER" is specified, sets the envelope sender to the
specified value (which will then subsequently be used if the article is
mailed). Returns the (new or current) envelope sender in any case.
- rawheaders ()
- Returns a list (or a reference to an array if in scalar context) of the
original header lines of the article, as read from the input source.
Terminating newlines are not included. (Continued headers are returned as
single strings with embedded newlines.)
- header_names ()
- Returns a list of the names of all headers currently present in the
article.
- headers ([FIRST [,NEXT [,LAST]]])
- Returns a list of all header strings with no terminating newlines.
Continued headers will have embedded newlines.
FIRST, NEXT and LAST are optional references to arrays of header names. The
order of the returned headers is as follows:
- headers specified by FIRST (one value only per name)
- headers in the order originally read in (if any)
- headers specified by NEXT (one value only per name)
- any remaining headers not named in LAST, sorted by name
- headers named in LAST (all values)
LAST overrides the original order of headers, but NEXT does not. Headers
named in LAST will also be grouped together by header name.
- headers_first (HDR...)
- Set default ordering for headers().
- headers_next (HDR...)
- Set default ordering for headers().
- headers_last (HDR...)
- Set default ordering for headers().
- set_headers ( NAME, VALUE [, NAME, VALUE [...]] )
- For each header name supplied, replace any current occurences of the
header with the specified value(s). Each value may be a single scalar, or
a reference to an array of values. Returns undef without completing the
assignments if any attempt is made to supply multiple values for a unique
header. Undef or empty values cause the header to be deleted. (If an array
is supplied, it is not copied. This is probably a mistake and should not
be relied on.)
- add_headers ( NAME, VALUE [, NAME, VALUE [...]] )
- Add new header values without affecting existing ones. Each value is
either a single scalar, or a reference to an array of values. Returns
undef without completing if any attempt is made to supply duplicate values
for a unique header. (If an array reference is supplied, the array is
copied.)
- drop_headers ( NAME [, NAME [...]] )
- Delete all values of the specified header(s).
- header ( NAME )
- Returns a list of values for the specified header. Returns a null list if
the header does not exist. In scalar context, returns the first value
found or undef.
- rename_header ( SRC, DEST [, ACTION] )
- Transform the name of a header without touching the value. Fails if the
source header does not exist. Returns undef on failure, true on success.
Optional ACTION (may be "drop", "clobber",
"add", or "fail" (default)), specifies what to do if
both source and destination exist:
ACTION PREVIOUS DEST
drop unchanged (SRC dropped)
clobber dropped (SRC replaces DEST)
add preserved (SRC added to DEST)
fail unchanged (operation fails)
- body ()
- Return the body of the article as a list of lines (no newlines), or a
reference to an array in scalar context (the array may be modified in this
case).
- lines ()
- Returns the number of lines in the article body.
- bytes ()
- Returns the total size of the article body, not counting newlines.
- set_body ( BODY )
- Replace the current article body with the specified text. Expects a list,
each item of which is either one line, or multiple lines separated by
newlines. (Trailing newlines on the values are ignored.)
- add_body ( BODY )
- Append the specified text to the current article body. Expects a list,
each item of which is either one line, or multiple lines separated by
newlines, or a reference to an array of lines. (Trailing newlines on the
values are ignored.)
- trim_blank_lines ()
- Remove any trailing blank lines from the article body. Returns the number
of lines removed.
- read_headers ( SOURCE, MAXSIZE )
- Read article headers (terminated by an empty line) from the specified
source (see "read" for defintion of allowed sources).
Gives up (returning undef) if more than MAXSIZE bytes are read. Returns the
amount read.
- read_body ( SOURCE, MAXSIZE )
- Read an article body from the specified source (see "read").
Stops at end of file; fails (returning undef) if MAXSIZE is reached prior
to that point. Returns the number of bytes read (may be 0 if the body is
null).
Trailing blank lines are NOT removed (an incompatible, but regrettably
necessary, change from previous versions); see trim_blank_lines if you
need to do that.
- read ( SOURCE [,MAXSIZE [,MAXHEADS]] )
- Reads in an article from "SOURCE".
"SOURCE" may be any of the following:
- a CODE ref, which is called to return lines or chunks of data
- an ARRAY ref, assumed to contain a list of lines with optional line
terminators
- a SCALAR ref, assumed to contain text with embedded newlines
- a scalar, assumed to be a filename, which is opened and read
- anything else is assumed to be a glob, reference to a glob, or reference
to a filehandle, and is read from accordingly
When reading in articles, "MAXHEADS" is the maximum header size to
read (default 8k), and "MAXSIZE" is the maximum article body
size (default 256k). If "MAXSIZE" is explicitly specified as 0,
then no attempt at reading the body is made. Returns the total number of
bytes read, or undef if either limit is reached or no headers were
found.
- write ( FILE )
- Write the entire article to the specified filehandle reference.
- write_unique_file ( DIR [,MODE] )
- Write the article to a (hopefully) uniquely-named file in the specified
directory. The file is written under a temporary name (with a leading
period) and relinked when complete. Returns 1 if successful, otherwise
undef.
MODE is the access mode to use for the created file (default 644); this will
be modified in turn by the current umask.
The implementation is careful to avoid losing the file or clobbering
existing files even in the case of a name collision, but relies on POSIX
link() semantics and may fail on lesser operating systems (or buggy
NFS implementations).
- write_original ( FILE )
- Write the original headers followed by the article body to the specified
filehandle reference.
- sendmail ( [COMMAND] )
- Get or set the command and options that will be used to mail the article.
Defaults to a system dependent value such as
/usr/sbin/sendmail -oi -oem
- mail ( [RECIPIENTS...] )
- Mails the article to the specified list of recipients, or to the addressed
recipients in the header (To, Cc, Bcc) if none are supplied. Attempts to
set the envelope sender to the stored envelope sender, if set, so unset
that before mailing if you do not want this behavior.
- post ( [CONN] )
- Post the article. Avoids inews due to undesirable header munging and
unwarranted complaints to stderr. Takes an optional parameter which is a
Net::NNTP reference. If supplied, posts the article to it; otherwise opens
a new reader connection and posts to that.
Throws an exception containing the error message on failure.
- ihave ( [CONN] )
- Inject the article. Takes an optional parameter which is a Net::NNTP
reference. If supplied, posts the article to it; otherwise opens a new
transport connection and posts to that. All required headers must already
be present, including Path and Message-ID.
Throws an exception containing the error message on failure.
- add_message_id ( [PREFIX [, DOMAIN] ] )
- If the current article lacks a message-id, then create one.
- add_date ( [TIME] )
- If the current article lacks a date, then add one (in local time). If TIME
is specified (numerical Unix time), it is used instead of the current
time.
- sign_pgpmoose ( GROUP, PASSPHRASE [, KEYID] )
- Signs the article according to the PGPMoose spec. We require that pgp be
on the path to do this. Takes a "group" which can be either a
newsgroup or an address, a PGP password, and an optional key id and
returns a null list on success, the PGP error output as a list on failure.
If the key id is omitted, we will assume that if the group is an e-mail
address, the key id is that address surrounded by <>, and otherwise
the key id will be the group with a space on either side. This is so that
one can help PGP distinguish between the keys for (say) mod.config and
mod.config.status. The PGP key id should be something like:
Moderator of group.name <request-address@some.host>
The article to be signed must already have all of the headers needed by
PGPMoose (Newsgroups, From, Subject) or this will fail. Message-ID is
added if necessary.
- verify_pgpmoose ( GROUP )
- Verifies an article signature according to the PGPMoose spec. We require
that pgp be on the path to do this. Takes a "group" which can be
either a newsgroup or an address, and an optional key id.
Looks for a X-Auth header matching the specified group or address, and if
found, checks the validity of the signature. If successful, returns the
signer identity (from the PGP output), otherwise returns false.
- sign_control ( KEYID, PASSPHRASE [, HEADER [...] ] )
- Signs the article in the manner used for control messages. This is derived
from signcontrol, written by David Lawrence, but with fewer sanity checks
since we assume people know what they're doing. Caveat programmer.
We take a key id, a PGP password, and an optional list of extra headers to
add to the signature. By default, Subject, Control, Message-ID, Date,
From, and Sender are signed. Any signed header that isn't present in the
article will be signed with an empty value. Date and Message-ID are
automatically added if needed.
CAVEATS¶
This module is not fully transparent. In particular:
- -
- Case of headers is smashed
- -
- improper duplicate headers may be discarded
- -
- Broken or dubious header names are not preserved
These factors make it undesirable to use this module in news transit
applications.
AUTHOR¶
Written by Andrew Gierth <andrew@erlenstar.demon.co.uk>
Thanks to Russ Allbery <rra@stanford.edu> for comments and suggestions.
COPYRIGHT¶
Copyright 1997-2002 Andrew Gierth <andrew@erlenstar.demon.co.uk>
This code may be used and/or distributed under the same terms as Perl
itself.