1=encoding utf8
2
3=head1 NAME
4
5Mail::Message::Field::Full - construct one smart line in a message header
6
7=head1 INHERITANCE
8
9 Mail::Message::Field::Full
10   is a Mail::Message::Field
11   is a Mail::Reporter
12
13 Mail::Message::Field::Full is extended by
14   Mail::Message::Field::Structured
15   Mail::Message::Field::Unstructured
16
17=head1 SYNOPSIS
18
19 # Getting to understand the complexity of a header field ...
20
21 my $fast = $msg->head->get('subject');
22 my $full = Mail::Message::Field::Full->from($fast);
23
24 my $full = $msg->head->get('subject')->study;  # same
25 my $full = $msg->head->study('subject');       # same
26 my $full = $msg->study('subject');             # same
27
28 # ... or build a complex header field yourself
29
30 my $f = Mail::Message::Field::Full->new('To');
31 my $f = Mail::Message::Field::Full->new('Subject: hi!');
32 my $f = Mail::Message::Field::Full->new(Subject => 'hi!');
33
34=head1 DESCRIPTION
35
36This is the I<full> implementation of a header field: it has I<full>
37understanding of all predefined header fields.  These objects will be
38quite slow, because header fields can be very complex.  Of course, this
39class delivers the optimal result, but for a quite large penalty in
40performance and memory consumption.  Are you willing to accept?
41
42This class supports the common header description from RFC2822 (formerly
43RFC822), the extensions with respect to character set encodings as specified
44in RFC2047, and the extensions on language specification and long parameter
45wrapping from RFC2231.  If you do not need the latter two, then the
46L<Mail::Message::Field::Fast|Mail::Message::Field::Fast> and L<Mail::Message::Field::Flex|Mail::Message::Field::Flex>
47are enough for your application.
48
49Extends L<"DESCRIPTION" in Mail::Message::Field|Mail::Message::Field/"DESCRIPTION">.
50
51=head1 OVERLOADED
52
53Extends L<"OVERLOADED" in Mail::Message::Field|Mail::Message::Field/"OVERLOADED">.
54
55=over 4
56
57=item overload: B<"">
58
59Inherited, see L<Mail::Message::Field/"OVERLOADED">
60
61=item overload: B<0+>
62
63Inherited, see L<Mail::Message::Field/"OVERLOADED">
64
65=item overload: B<<=>>
66
67Inherited, see L<Mail::Message::Field/"OVERLOADED">
68
69=item overload: B<bool>
70
71Inherited, see L<Mail::Message::Field/"OVERLOADED">
72
73=item overload: B<cmp>
74
75Inherited, see L<Mail::Message::Field/"OVERLOADED">
76
77=item overload: B<stringification>
78
79In string context, the decoded body is returned, as if L<decodedBody()|Mail::Message::Field::Full/"Access to the body">
80would have been called.
81
82=back
83
84=head1 METHODS
85
86Extends L<"METHODS" in Mail::Message::Field|Mail::Message::Field/"METHODS">.
87
88=head2 Constructors
89
90Extends L<"Constructors" in Mail::Message::Field|Mail::Message::Field/"Constructors">.
91
92=over 4
93
94=item $obj-E<gt>B<clone>()
95
96Inherited, see L<Mail::Message::Field/"Constructors">
97
98=item Mail::Message::Field::Full-E<gt>B<from>($field, %options)
99
100Convert any $field (a L<Mail::Message::Field|Mail::Message::Field> object) into a new
101L<Mail::Message::Field::Full|Mail::Message::Field::Full> object.  This conversion is done the hard
102way: the string which is produced by the original object is parsed
103again.  Usually, the string which is parsed is exactly the line (or lines)
104as found in the original input source, which is a good thing because Full
105fields are much more careful with the actual content.
106
107%options are passed to the constructor (see L<new()|Mail::Message::Field::Full/"METHODS">).  In any case, some
108extensions of this Full field class is returned.  It depends on which
109field is created what kind of class we get.
110
111example:
112
113 my $fast = $msg->head->get('subject');
114 my $full = Mail::Message::Field::Full->from($fast);
115
116 my $full = $msg->head->get('subject')->study;  # same
117 my $full = $msg->head->study('subject');       # same
118 my $full = $msg->get('subject');               # same
119
120=item Mail::Message::Field::Full-E<gt>B<new>($data)
121
122Creating a new field object the correct way is a lot of work, because
123there is so much freedom in the RFCs, but at the same time so many
124restrictions.  Most fields are implemented, but if you have your own
125field (and do no want to contribute it to MailBox), then simply call
126new on your own package.
127
128You have the choice to instantiate the object as string or in prepared
129parts:
130
131=over 4
132
133=item * B<new> LINE, OPTIONS
134
135Pass a LINE as it could be found in a file: a (possibly folded) line
136which is terminated by a new-line.
137
138=item * B<new> NAME, [BODY], OPTIONS
139
140A set of values which shape the line.
141
142=back
143
144The NAME is a wellformed header name (you may use wellformedName()) to
145be sure about the casing.  The BODY is a string, one object, or an
146ref-array of objects.  In case of objects, they must fit to the
147constructor of the field: the types which are accepted may differ.
148The optional ATTRIBUTE list contains L<Mail::Message::Field::Attribute|Mail::Message::Field::Attribute>
149objects.  Finally, there are some OPTIONS.
150
151 -Option  --Defined in     --Default
152  charset                    undef
153  encoding                   'q'
154  force                      false
155  language                   undef
156  log       Mail::Reporter   'WARNINGS'
157  trace     Mail::Reporter   'WARNINGS'
158
159=over 2
160
161=item charset => STRING
162
163The body is specified in utf8, and must become 7-bits ascii to be
164transmited.  Specify a charset to which the multi-byte utf8 is converted
165before it gets encoded.  See L<encode()|Mail::Message::Field::Full/"Internals">, which does the job.
166
167=item encoding => 'q'|'Q'|'b'|'B'
168
169Non-ascii characters are encoded using Quoted-Printable ('q' or 'Q') or
170Base64 ('b' or 'B') encoding.
171
172=item force => BOOLEAN
173
174Enforce encoding in the specified charset, even when it is not needed
175because the body does not contain any non-ascii characters.
176
177=item language => STRING
178
179The language used can be specified, however is rarely used my mail clients.
180
181=item log => LEVEL
182
183=item trace => LEVEL
184
185=back
186
187example:
188
189 my $s = Mail::Message::Field::Full->new('Subject: Hello World');
190 my $s = Mail::Message::Field::Full->new('Subject', 'Hello World');
191
192 my @attrs   = (Mail::Message::Field::Attribute->new(...), ...);
193 my @options = (extra => 'the color blue');
194 my $t = Mail::Message::Field::Full->new(To => \@addrs, @attrs, @options);
195
196=back
197
198=head2 The field
199
200Extends L<"The field" in Mail::Message::Field|Mail::Message::Field/"The field">.
201
202=over 4
203
204=item $obj-E<gt>B<isStructured>()
205
206=item Mail::Message::Field::Full-E<gt>B<isStructured>()
207
208Inherited, see L<Mail::Message::Field/"The field">
209
210=item $obj-E<gt>B<length>()
211
212Inherited, see L<Mail::Message::Field/"The field">
213
214=item $obj-E<gt>B<nrLines>()
215
216Inherited, see L<Mail::Message::Field/"The field">
217
218=item $obj-E<gt>B<print>( [$fh] )
219
220Inherited, see L<Mail::Message::Field/"The field">
221
222=item $obj-E<gt>B<size>()
223
224Inherited, see L<Mail::Message::Field/"The field">
225
226=item $obj-E<gt>B<string>( [$wrap] )
227
228Inherited, see L<Mail::Message::Field/"The field">
229
230=item $obj-E<gt>B<toDisclose>()
231
232Inherited, see L<Mail::Message::Field/"The field">
233
234=back
235
236=head2 Access to the name
237
238Extends L<"Access to the name" in Mail::Message::Field|Mail::Message::Field/"Access to the name">.
239
240=over 4
241
242=item $obj-E<gt>B<Name>()
243
244Inherited, see L<Mail::Message::Field/"Access to the name">
245
246=item $obj-E<gt>B<name>()
247
248Inherited, see L<Mail::Message::Field/"Access to the name">
249
250=item $obj-E<gt>B<wellformedName>( [STRING] )
251
252Inherited, see L<Mail::Message::Field/"Access to the name">
253
254=back
255
256=head2 Access to the body
257
258Extends L<"Access to the body" in Mail::Message::Field|Mail::Message::Field/"Access to the body">.
259
260=over 4
261
262=item $obj-E<gt>B<body>()
263
264Inherited, see L<Mail::Message::Field/"Access to the body">
265
266=item $obj-E<gt>B<decodedBody>(%options)
267
268Returns the unfolded body of the field, where encodings are resolved.  The
269returned line will still contain comments and such.  The %options are passed
270to the decoder, see L<decode()|Mail::Message::Field::Full/"Internals">.
271
272BE WARNED: if the field is a structured field, the content may change syntax,
273because of encapsulated special characters.  By default, the body is decoded
274as text, which results in a small difference within comments as well
275(read the RFC).
276
277=item $obj-E<gt>B<folded>()
278
279Inherited, see L<Mail::Message::Field/"Access to the body">
280
281=item $obj-E<gt>B<foldedBody>( [$body] )
282
283Inherited, see L<Mail::Message::Field/"Access to the body">
284
285=item $obj-E<gt>B<stripCFWS>( [STRING] )
286
287=item Mail::Message::Field::Full-E<gt>B<stripCFWS>( [STRING] )
288
289Inherited, see L<Mail::Message::Field/"Access to the body">
290
291=item $obj-E<gt>B<unfoldedBody>( [$body, [$wrap]] )
292
293Inherited, see L<Mail::Message::Field/"Access to the body">
294
295=back
296
297=head2 Access to the content
298
299Extends L<"Access to the content" in Mail::Message::Field|Mail::Message::Field/"Access to the content">.
300
301=over 4
302
303=item $obj-E<gt>B<addresses>()
304
305Inherited, see L<Mail::Message::Field/"Access to the content">
306
307=item $obj-E<gt>B<attribute>( $name, [$value] )
308
309Inherited, see L<Mail::Message::Field/"Access to the content">
310
311=item $obj-E<gt>B<attributes>()
312
313Inherited, see L<Mail::Message::Field/"Access to the content">
314
315=item $obj-E<gt>B<beautify>()
316
317For structured header fields, this removes the original encoding of the
318field's body (the format as it was offered to L<parse()|Mail::Message::Field::Full/"Parsing">), therefore the
319next request for the field will have to re-produce the read data clean
320and nice.  For unstructured bodies, this method doesn't do a thing.
321
322=item $obj-E<gt>B<comment>( [STRING] )
323
324Inherited, see L<Mail::Message::Field/"Access to the content">
325
326=item $obj-E<gt>B<createComment>(STRING, %options)
327
328=item Mail::Message::Field::Full-E<gt>B<createComment>(STRING, %options)
329
330Create a comment to become part in a field.  Comments are automatically
331included within parenthesis.  Matching pairs of parenthesis are
332permitted within the STRING.  When a non-matching parenthesis are used,
333it is only permitted with an escape (a backslash) in front of them.
334These backslashes will be added automatically if needed (don't worry!).
335Backslashes will stay, except at the end, where it will be doubled.
336
337The %options are C<charset>, C<language>, and C<encoding> as always.
338The created comment is returned.
339
340=item $obj-E<gt>B<createPhrase>(STRING, %options)
341
342=item Mail::Message::Field::Full-E<gt>B<createPhrase>(STRING, %options)
343
344A phrase is a text which plays a well defined role.  This is the main
345difference with comments, which have do specified meaning.  Some special
346characters in the phrase will cause it to be surrounded with double
347quotes: do not specify them yourself.
348
349The %options are C<charset>, C<language>, and C<encoding>, as always.
350
351=item $obj-E<gt>B<study>()
352
353Inherited, see L<Mail::Message::Field/"Access to the content">
354
355=item $obj-E<gt>B<toDate>( [$time] )
356
357=item Mail::Message::Field::Full-E<gt>B<toDate>( [$time] )
358
359Inherited, see L<Mail::Message::Field/"Access to the content">
360
361=item $obj-E<gt>B<toInt>()
362
363Inherited, see L<Mail::Message::Field/"Access to the content">
364
365=back
366
367=head2 Other methods
368
369Extends L<"Other methods" in Mail::Message::Field|Mail::Message::Field/"Other methods">.
370
371=over 4
372
373=item $obj-E<gt>B<dateToTimestamp>(STRING)
374
375=item Mail::Message::Field::Full-E<gt>B<dateToTimestamp>(STRING)
376
377Inherited, see L<Mail::Message::Field/"Other methods">
378
379=back
380
381=head2 Internals
382
383Extends L<"Internals" in Mail::Message::Field|Mail::Message::Field/"Internals">.
384
385=over 4
386
387=item $obj-E<gt>B<consume>( $line | <$name,<$body|$objects>> )
388
389Inherited, see L<Mail::Message::Field/"Internals">
390
391=item $obj-E<gt>B<decode>(STRING, %options)
392
393=item Mail::Message::Field::Full-E<gt>B<decode>(STRING, %options)
394
395Decode field encoded STRING to an utf8 string.  The input STRING is part of
396a header field, and as such, may contain encoded words in C<=?...?.?...?=>
397format defined by RFC2047.  The STRING may contain multiple encoded parts,
398maybe using different character sets.
399
400Be warned:  you MUST first interpret the field into parts, like phrases and
401comments, and then decode each part separately, otherwise the decoded text
402may interfere with your markup characters.
403
404Be warned: language information, which is defined in RFC2231, is ignored.
405
406Encodings with unknown charsets are left untouched [requires v2.085,
407otherwise croaked].  Unknown characters within an charset are replaced by
408a '?'.
409
410 -Option --Default
411  is_text  1
412
413=over 2
414
415=item is_text => BOOLEAN
416
417Encoding on text is slightly more complicated than encoding structured data,
418because it contains blanks.  Visible blanks have to be ignored between two
419encoded words in the text, but not when an encoded word follows or precedes
420an unencoded word.  Phrases and comments are texts.
421
422=back
423
424example:
425
426 print Mail::Message::Field::Full->decode('=?iso-8859-1?Q?J=F8rgen?=');
427    # prints   JE<0slash>rgen
428
429=item $obj-E<gt>B<defaultWrapLength>( [$length] )
430
431Inherited, see L<Mail::Message::Field/"Internals">
432
433=item $obj-E<gt>B<encode>(STRING, %options)
434
435Encode the (possibly utf8 encoded) STRING to a string which is acceptable
436to the RFC2047 definition of a header: only containing us-ascii characters.
437
438 -Option  --Default
439  charset   'us-ascii'
440  encoding  'q'
441  force     <flase>
442  language  undef
443  name      undef
444
445=over 2
446
447=item charset => STRING
448
449STRING is an utf8 string which has to be translated into any byte-wise
450character set for transport, because MIME-headers can only contain ascii
451characters.
452
453=item encoding => 'q'|'Q'|'b'|'B'
454
455The character encoding to be used.  With C<q> or C<Q>, quoted-printable
456encoding will be used.  With C<b > or C<B >, base64 encoding will be taken.
457
458=item force => BOOLEAN
459
460Encode the string, even when it only contains us-ascii characters.  By
461default, this is off because it decreases readibility of the produced
462header fields.
463
464=item language => STRING
465
466RFC2231 defines how to specify language encodings in encoded words.  The
467STRING is a strandard iso language name.
468
469=item name => STRING
470
471[3.002] When the name of the field is given, the first encoded line will
472be shorter.
473
474=back
475
476=item $obj-E<gt>B<fold>( $name, $body, [$maxchars] )
477
478=item Mail::Message::Field::Full-E<gt>B<fold>( $name, $body, [$maxchars] )
479
480Inherited, see L<Mail::Message::Field/"Internals">
481
482=item $obj-E<gt>B<setWrapLength>( [$length] )
483
484Inherited, see L<Mail::Message::Field/"Internals">
485
486=item $obj-E<gt>B<stringifyData>(STRING|ARRAY|$objects)
487
488Inherited, see L<Mail::Message::Field/"Internals">
489
490=item $obj-E<gt>B<unfold>(STRING)
491
492Inherited, see L<Mail::Message::Field/"Internals">
493
494=back
495
496=head2 Parsing
497
498You probably do not want to call these parsing methods yourself: use
499the standard constructors (L<new()|Mail::Message::Field::Full/"METHODS">) and it will be done for you.
500
501=over 4
502
503=item $obj-E<gt>B<consumeComment>(STRING)
504
505=item Mail::Message::Field::Full-E<gt>B<consumeComment>(STRING)
506
507Try to read a comment from the STRING.  When successful, the comment
508without encapsulation parenthesis is returned, together with the rest
509of the string.
510
511=item $obj-E<gt>B<consumeDotAtom>(STRING)
512
513Returns three elemens: the atom-text, the rest string, and the
514concatenated comments.  Both atom and comments can be undef.
515
516=item $obj-E<gt>B<consumePhrase>(STRING)
517
518=item Mail::Message::Field::Full-E<gt>B<consumePhrase>(STRING)
519
520Take the STRING, and try to strip-off a valid phrase.  In the obsolete
521phrase syntax, any sequence of words is accepted as phrase (as long as
522certain special characters are not used).  RFC2822 is stricter: only
523one word or a quoted string is allowed.  As always, the obsolete
524syntax is accepted, and the new syntax is produced.
525
526This method returns two elements: the phrase (or undef) followed
527by the resulting string.  The phrase will be removed from the optional
528quotes.  Be warned that C<""> will return an empty, valid phrase.
529
530example:
531
532 my ($phrase, $rest) = $field->consumePhrase( q["hi!" <sales@example.com>] );
533
534=item $obj-E<gt>B<parse>(STRING)
535
536Get the detailed information from the STRING, and store the data found
537in the field object.  The accepted input is very field type dependent.
538Unstructured fields do no parsing whatsoever.
539
540=item $obj-E<gt>B<produceBody>()
541
542Produce the text for the field, based on the information stored within the
543field object.
544
545Usually, you wish the exact same line as was found in the input source
546of a message.  But when you have created a field yourself, it should get
547formatted.  You may call L<beautify()|Mail::Message::Field::Full/"Access to the content"> on a preformatted field to enforce
548a call to this method when the field is needed later.
549
550=back
551
552=head2 Error handling
553
554Extends L<"Error handling" in Mail::Message::Field|Mail::Message::Field/"Error handling">.
555
556=over 4
557
558=item $obj-E<gt>B<AUTOLOAD>()
559
560Inherited, see L<Mail::Reporter/"Error handling">
561
562=item $obj-E<gt>B<addReport>($object)
563
564Inherited, see L<Mail::Reporter/"Error handling">
565
566=item $obj-E<gt>B<defaultTrace>( [$level]|[$loglevel, $tracelevel]|[$level, $callback] )
567
568=item Mail::Message::Field::Full-E<gt>B<defaultTrace>( [$level]|[$loglevel, $tracelevel]|[$level, $callback] )
569
570Inherited, see L<Mail::Reporter/"Error handling">
571
572=item $obj-E<gt>B<errors>()
573
574Inherited, see L<Mail::Reporter/"Error handling">
575
576=item $obj-E<gt>B<log>( [$level, [$strings]] )
577
578=item Mail::Message::Field::Full-E<gt>B<log>( [$level, [$strings]] )
579
580Inherited, see L<Mail::Reporter/"Error handling">
581
582=item $obj-E<gt>B<logPriority>($level)
583
584=item Mail::Message::Field::Full-E<gt>B<logPriority>($level)
585
586Inherited, see L<Mail::Reporter/"Error handling">
587
588=item $obj-E<gt>B<logSettings>()
589
590Inherited, see L<Mail::Reporter/"Error handling">
591
592=item $obj-E<gt>B<notImplemented>()
593
594Inherited, see L<Mail::Reporter/"Error handling">
595
596=item $obj-E<gt>B<report>( [$level] )
597
598Inherited, see L<Mail::Reporter/"Error handling">
599
600=item $obj-E<gt>B<reportAll>( [$level] )
601
602Inherited, see L<Mail::Reporter/"Error handling">
603
604=item $obj-E<gt>B<trace>( [$level] )
605
606Inherited, see L<Mail::Reporter/"Error handling">
607
608=item $obj-E<gt>B<warnings>()
609
610Inherited, see L<Mail::Reporter/"Error handling">
611
612=back
613
614=head2 Cleanup
615
616Extends L<"Cleanup" in Mail::Message::Field|Mail::Message::Field/"Cleanup">.
617
618=over 4
619
620=item $obj-E<gt>B<DESTROY>()
621
622Inherited, see L<Mail::Reporter/"Cleanup">
623
624=back
625
626=head1 DETAILS
627
628Extends L<"DETAILS" in Mail::Message::Field|Mail::Message::Field/"DETAILS">.
629
630=head1 DIAGNOSTICS
631
632=over 4
633
634=item Warning: Field content is not numerical: $content
635
636The numeric value of a field is requested (for instance the C<Lines> or
637C<Content-Length> fields should be numerical), however the data contains
638weird characters.
639
640=item Warning: Illegal character in charset '$charset'
641
642The field is created with an utf8 string which only contains data from the
643specified character set.  However, that character set can never be a valid
644name because it contains characters which are not permitted.
645
646=item Warning: Illegal character in field name $name
647
648A new field is being created which does contain characters not permitted
649by the RFCs.  Using this field in messages may break other e-mail clients
650or transfer agents, and therefore mutulate or extinguish your message.
651
652=item Warning: Illegal character in language '$lang'
653
654The field is created with data which is specified to be in a certain language,
655however, the name of the language cannot be valid: it contains characters
656which are not permitted by the RFCs.
657
658=item Warning: Illegal encoding '$encoding', used 'q'
659
660The RFCs only permit base64 (C<b > or C<B >) or quoted-printable
661(C<q> or C<Q>) encoding.  Other than these four options are illegal.
662
663=item Error: Package $package does not implement $method.
664
665Fatal error: the specific package (or one of its superclasses) does not
666implement this method where it should. This message means that some other
667related classes do implement this method however the class at hand does
668not.  Probably you should investigate this and probably inform the author
669of the package.
670
671=back
672
673=head1 SEE ALSO
674
675This module is part of Mail-Message distribution version 3.011,
676built on July 27, 2021. Website: F<http://perl.overmeer.net/CPAN/>
677
678=head1 LICENSE
679
680Copyrights 2001-2021 by [Mark Overmeer <markov@cpan.org>]. For other contributors see ChangeLog.
681
682This program is free software; you can redistribute it and/or modify it
683under the same terms as Perl itself.
684See F<http://dev.perl.org/licenses/>
685
686