Commit | Line | Data |
d80786d0 |
1 | package HTML::Zoom; |
2 | |
1cf03540 |
3 | use strictures 1; |
d80786d0 |
4 | |
5 | use HTML::Zoom::ZConfig; |
bf5a23d0 |
6 | use HTML::Zoom::ReadFH; |
655965b3 |
7 | use HTML::Zoom::Transform; |
eeeb0921 |
8 | use HTML::Zoom::TransformBuilder; |
d80786d0 |
9 | |
f107bef7 |
10 | our $VERSION = '0.009004'; |
7af7362d |
11 | |
12 | $VERSION = eval $VERSION; |
13 | |
d80786d0 |
14 | sub new { |
15 | my ($class, $args) = @_; |
16 | my $new = {}; |
17 | $new->{zconfig} = HTML::Zoom::ZConfig->new($args->{zconfig}||{}); |
18 | bless($new, $class); |
19 | } |
20 | |
21 | sub zconfig { shift->_self_or_new->{zconfig} } |
22 | |
23 | sub _self_or_new { |
24 | ref($_[0]) ? $_[0] : $_[0]->new |
25 | } |
26 | |
27 | sub _with { |
28 | bless({ %{$_[0]}, %{$_[1]} }, ref($_[0])); |
29 | } |
30 | |
7567494d |
31 | sub from_events { |
d80786d0 |
32 | my $self = shift->_self_or_new; |
33 | $self->_with({ |
7567494d |
34 | initial_events => shift, |
d80786d0 |
35 | }); |
36 | } |
37 | |
7567494d |
38 | sub from_html { |
39 | my $self = shift->_self_or_new; |
40 | $self->from_events($self->zconfig->parser->html_to_events($_[0])) |
41 | } |
42 | |
bf5a23d0 |
43 | sub from_file { |
44 | my $self = shift->_self_or_new; |
45 | my $filename = shift; |
46 | $self->from_html(do { local (@ARGV, $/) = ($filename); <> }); |
47 | } |
48 | |
d80786d0 |
49 | sub to_stream { |
50 | my $self = shift; |
51 | die "No events to build from - forgot to call from_html?" |
52 | unless $self->{initial_events}; |
53 | my $sutils = $self->zconfig->stream_utils; |
54 | my $stream = $sutils->stream_from_array(@{$self->{initial_events}}); |
2f0c6a86 |
55 | $stream = $_->apply_to_stream($stream) for @{$self->{transforms}||[]}; |
d80786d0 |
56 | $stream |
57 | } |
58 | |
bf5a23d0 |
59 | sub to_fh { |
60 | HTML::Zoom::ReadFH->from_zoom(shift); |
61 | } |
62 | |
7567494d |
63 | sub to_events { |
64 | my $self = shift; |
65 | [ $self->zconfig->stream_utils->stream_to_array($self->to_stream) ]; |
66 | } |
67 | |
bf5a23d0 |
68 | sub run { |
69 | my $self = shift; |
7567494d |
70 | $self->to_events; |
bf5a23d0 |
71 | return |
72 | } |
73 | |
74 | sub apply { |
75 | my ($self, $code) = @_; |
76 | local $_ = $self; |
77 | $self->$code; |
78 | } |
79 | |
fdb039c6 |
80 | sub apply_if { |
81 | my ($self, $predicate, $code) = @_; |
82 | if($predicate) { |
83 | local $_ = $self; |
84 | $self->$code; |
85 | } |
86 | else { |
87 | $self; |
88 | } |
89 | } |
90 | |
d80786d0 |
91 | sub to_html { |
92 | my $self = shift; |
93 | $self->zconfig->producer->html_from_stream($self->to_stream); |
94 | } |
95 | |
96 | sub memoize { |
97 | my $self = shift; |
98 | ref($self)->new($self)->from_html($self->to_html); |
99 | } |
100 | |
eeeb0921 |
101 | sub with_transform { |
1c4455ae |
102 | my $self = shift->_self_or_new; |
eeeb0921 |
103 | my ($transform) = @_; |
d80786d0 |
104 | $self->_with({ |
2f0c6a86 |
105 | transforms => [ |
106 | @{$self->{transforms}||[]}, |
eeeb0921 |
107 | $transform |
2f0c6a86 |
108 | ] |
d80786d0 |
109 | }); |
110 | } |
eeeb0921 |
111 | |
112 | sub with_filter { |
113 | my $self = shift->_self_or_new; |
114 | my ($selector, $filter) = @_; |
115 | $self->with_transform( |
116 | HTML::Zoom::Transform->new({ |
117 | zconfig => $self->zconfig, |
118 | selector => $selector, |
119 | filters => [ $filter ] |
120 | }) |
121 | ); |
122 | } |
d80786d0 |
123 | |
124 | sub select { |
1c4455ae |
125 | my $self = shift->_self_or_new; |
126 | my ($selector) = @_; |
eeeb0921 |
127 | return HTML::Zoom::TransformBuilder->new({ |
128 | zconfig => $self->zconfig, |
129 | selector => $selector, |
130 | proto => $self |
131 | }); |
d80786d0 |
132 | } |
133 | |
134 | # There's a bug waiting to happen here: if you do something like |
135 | # |
136 | # $zoom->select('.foo') |
1c4455ae |
137 | # ->remove_attribute(class => 'foo') |
d80786d0 |
138 | # ->then |
139 | # ->well_anything_really |
140 | # |
141 | # the second action won't execute because it doesn't match anymore. |
142 | # Ideally instead we'd merge the match subs but that's more complex to |
143 | # implement so I'm deferring it for the moment. |
144 | |
145 | sub then { |
146 | my $self = shift; |
2f0c6a86 |
147 | die "Can't call ->then without a previous transform" |
148 | unless $self->{transforms}; |
149 | $self->select($self->{transforms}->[-1]->selector); |
d80786d0 |
150 | } |
151 | |
152 | 1; |
153 | |
154 | =head1 NAME |
155 | |
156 | HTML::Zoom - selector based streaming template engine |
157 | |
158 | =head1 SYNOPSIS |
159 | |
160 | use HTML::Zoom; |
161 | |
162 | my $template = <<HTML; |
163 | <html> |
164 | <head> |
165 | <title>Hello people</title> |
166 | </head> |
167 | <body> |
168 | <h1 id="greeting">Placeholder</h1> |
169 | <div id="list"> |
170 | <span> |
171 | <p>Name: <span class="name">Bob</span></p> |
172 | <p>Age: <span class="age">23</span></p> |
173 | </span> |
174 | <hr class="between" /> |
175 | </div> |
176 | </body> |
177 | </html> |
178 | HTML |
179 | |
180 | my $output = HTML::Zoom |
181 | ->from_html($template) |
182 | ->select('title, #greeting')->replace_content('Hello world & dog!') |
183 | ->select('#list')->repeat_content( |
184 | [ |
185 | sub { |
186 | $_->select('.name')->replace_content('Matt') |
187 | ->select('.age')->replace_content('26') |
188 | }, |
189 | sub { |
190 | $_->select('.name')->replace_content('Mark') |
191 | ->select('.age')->replace_content('0x29') |
192 | }, |
193 | sub { |
194 | $_->select('.name')->replace_content('Epitaph') |
195 | ->select('.age')->replace_content('<redacted>') |
196 | }, |
197 | ], |
198 | { repeat_between => '.between' } |
199 | ) |
200 | ->to_html; |
201 | |
202 | will produce: |
203 | |
204 | =begin testinfo |
205 | |
206 | my $expect = <<HTML; |
207 | |
208 | =end testinfo |
209 | |
210 | <html> |
211 | <head> |
212 | <title>Hello world & dog!</title> |
213 | </head> |
214 | <body> |
215 | <h1 id="greeting">Hello world & dog!</h1> |
216 | <div id="list"> |
217 | <span> |
218 | <p>Name: <span class="name">Matt</span></p> |
219 | <p>Age: <span class="age">26</span></p> |
220 | </span> |
221 | <hr class="between" /> |
222 | <span> |
223 | <p>Name: <span class="name">Mark</span></p> |
224 | <p>Age: <span class="age">0x29</span></p> |
225 | </span> |
226 | <hr class="between" /> |
227 | <span> |
228 | <p>Name: <span class="name">Epitaph</span></p> |
229 | <p>Age: <span class="age"><redacted></span></p> |
230 | </span> |
231 | |
232 | </div> |
233 | </body> |
234 | </html> |
235 | |
236 | =begin testinfo |
237 | |
238 | HTML |
239 | is($output, $expect, 'Synopsis code works ok'); |
240 | |
241 | =end testinfo |
242 | |
1c4455ae |
243 | =head1 DANGER WILL ROBINSON |
244 | |
245 | This is a 0.9 release. That means that I'm fairly happy the API isn't going |
246 | to change in surprising and upsetting ways before 1.0 and a real compatibility |
247 | freeze. But it also means that if it turns out there's a mistake the size of |
248 | a politician's ego in the API design that I haven't spotted yet there may be |
249 | a bit of breakage between here and 1.0. Hopefully not though. Appendages |
250 | crossed and all that. |
251 | |
252 | Worse still, the rest of the distribution isn't documented yet. I'm sorry. |
253 | I suck. But lots of people have been asking me to ship this, docs or no, so |
254 | having got this class itself at least somewhat documented I figured now was |
255 | a good time to cut a first real release. |
256 | |
257 | =head1 DESCRIPTION |
258 | |
259 | HTML::Zoom is a lazy, stream oriented, streaming capable, mostly functional, |
260 | CSS selector based semantic templating engine for HTML and HTML-like |
261 | document formats. |
262 | |
263 | Which is, on the whole, a bit of a mouthful. So let me step back a moment |
264 | and explain why you care enough to understand what I mean: |
265 | |
266 | =head2 JQUERY ENVY |
267 | |
268 | HTML::Zoom is the cure for JQuery envy. When your javascript guy pushes a |
269 | piece of data into a document by doing: |
270 | |
271 | $('.username').replaceAll(username); |
272 | |
273 | In HTML::Zoom one can write |
274 | |
275 | $zoom->select('.username')->replace_content($username); |
276 | |
277 | which is, I hope, almost as clear, hampered only by the fact that Zoom can't |
278 | assume a global document and therefore has nothing quite so simple as the |
279 | $() function to get the initial selection. |
280 | |
281 | L<HTML::Zoom::SelectorParser> implements a subset of the JQuery selector |
282 | specification, and will continue to track that rather than the W3C standards |
283 | for the forseeable future on grounds of pragmatism. Also on grounds of their |
284 | spec is written in EN_US rather than EN_W3C, and I read the former much better. |
285 | |
286 | I am happy to admit that it's very, very much a subset at the moment - see the |
287 | L<HTML::Zoom::SelectorParser> POD for what's currently there, and expect more |
288 | and more to be supported over time as we need it and patch it in. |
289 | |
290 | =head2 CLEAN TEMPLATES |
291 | |
292 | HTML::Zoom is the cure for messy templates. How many times have you looked at |
293 | templates like this: |
294 | |
295 | <form action="/somewhere"> |
296 | [% FOREACH field IN fields %] |
297 | <label for="[% field.id %]">[% field.label %]</label> |
298 | <input name="[% field.name %]" type="[% field.type %]" value="[% field.value %]" /> |
299 | [% END %] |
300 | </form> |
301 | |
302 | and despaired of the fact that neither the HTML structure nor the logic are |
303 | remotely easy to read? Fortunately, with HTML::Zoom we can separate the two |
304 | cleanly: |
305 | |
306 | <form class="myform" action="/somewhere"> |
307 | <label /> |
308 | <input /> |
309 | </form> |
310 | |
311 | $zoom->select('.myform')->repeat_content([ |
312 | map { my $field = $_; sub { |
313 | |
314 | $_->select('label') |
2daa653a |
315 | ->add_to_attribute( for => $field->{id} ) |
1c4455ae |
316 | ->then |
317 | ->replace_content( $field->{label} ) |
318 | |
319 | ->select('input') |
2daa653a |
320 | ->add_to_attribute( name => $field->{name} ) |
1c4455ae |
321 | ->then |
2daa653a |
322 | ->add_to_attribute( type => $field->{type} ) |
1c4455ae |
323 | ->then |
2daa653a |
324 | ->add_to_attribute( value => $field->{value} ) |
1c4455ae |
325 | |
326 | } } @fields |
327 | ]); |
328 | |
329 | This is, admittedly, very much not shorter. However, it makes it extremely |
330 | clear what's happening and therefore less hassle to maintain. Especially |
331 | because it allows the designer to fiddle with the HTML without cutting |
332 | himself on sharp ELSE clauses, and the developer to add available data to |
333 | the template without getting angle bracket cuts on sensitive parts. |
334 | |
335 | Better still, HTML::Zoom knows that it's inserting content into HTML and |
336 | can escape it for you - the example template should really have been: |
337 | |
338 | <form action="/somewhere"> |
339 | [% FOREACH field IN fields %] |
340 | <label for="[% field.id | html %]">[% field.label | html %]</label> |
341 | <input name="[% field.name | html %]" type="[% field.type | html %]" value="[% field.value | html %]" /> |
342 | [% END %] |
343 | </form> |
344 | |
345 | and frankly I'll take slightly more code any day over *that* crawling horror. |
346 | |
347 | (addendum: I pick on L<Template Toolkit|Template> here specifically because |
348 | it's the template system I hate the least - for text templating, I don't |
349 | honestly think I'll ever like anything except the next version of Template |
350 | Toolkit better - but HTML isn't text. Zoom knows that. Do you?) |
351 | |
352 | =head2 PUTTING THE FUN INTO FUNCTIONAL |
353 | |
354 | The principle of HTML::Zoom is to provide a reusable, functional container |
355 | object that lets you build up a set of transforms to be applied; every method |
356 | call you make on a zoom object returns a new object, so it's safe to do so |
357 | on one somebody else gave you without worrying about altering state (with |
358 | the notable exception of ->next for stream objects, which I'll come to later). |
359 | |
360 | So: |
361 | |
362 | my $z2 = $z1->select('.name')->replace_content($name); |
363 | |
364 | my $z3 = $z2->select('.title')->replace_content('Ms.'); |
365 | |
366 | each time produces a new Zoom object. If you want to package up a set of |
367 | transforms to re-use, HTML::Zoom provides an 'apply' method: |
368 | |
369 | my $add_name = sub { $_->select('.name')->replace_content($name) }; |
370 | |
371 | my $same_as_z2 = $z1->apply($add_name); |
372 | |
373 | =head2 LAZINESS IS A VIRTUE |
374 | |
375 | HTML::Zoom does its best to defer doing anything until it's absolutely |
376 | required. The only point at which it descends into state is when you force |
377 | it to create a stream, directly by: |
378 | |
c9e76777 |
379 | my $stream = $zoom->to_stream; |
1c4455ae |
380 | |
381 | while (my $evt = $stream->next) { |
382 | # handle zoom event here |
383 | } |
384 | |
385 | or indirectly via: |
386 | |
387 | my $final_html = $zoom->to_html; |
388 | |
389 | my $fh = $zoom->to_fh; |
390 | |
391 | while (my $chunk = $fh->getline) { |
392 | ... |
393 | } |
394 | |
395 | Better still, the $fh returned doesn't create its stream until the first |
396 | call to getline, which means that until you call that and force it to be |
397 | stateful you can get back to the original stateless Zoom object via: |
398 | |
399 | my $zoom = $fh->to_zoom; |
400 | |
401 | which is exceedingly handy for filtering L<Plack> PSGI responses, among other |
402 | things. |
403 | |
404 | Because HTML::Zoom doesn't try and evaluate everything up front, you can |
405 | generally put things together in whatever order is most appropriate. This |
406 | means that: |
407 | |
408 | my $start = HTML::Zoom->from_html($html); |
409 | |
410 | my $zoom = $start->select('div')->replace_content('THIS IS A DIV!'); |
411 | |
412 | and: |
413 | |
414 | my $start = HTML::Zoom->select('div')->replace_content('THIS IS A DIV!'); |
415 | |
416 | my $zoom = $start->from_html($html); |
417 | |
418 | will produce equivalent final $zoom objects, thus proving that there can be |
419 | more than one way to do it without one of them being a |
420 | L<bait and switch|Switch>. |
421 | |
422 | =head2 STOCKTON TO DARLINGTON UNDER STREAM POWER |
423 | |
424 | HTML::Zoom's execution always happens in terms of streams under the hood |
425 | - that is, the basic pattern for doing anything is - |
426 | |
427 | my $stream = get_stream_from_somewhere |
428 | |
429 | while (my ($evt) = $stream->next) { |
430 | # do something with the event |
431 | } |
432 | |
433 | More importantly, all selectors and filters are also built as stream |
434 | operations, so a selector and filter pair is effectively: |
435 | |
436 | sub next { |
437 | my ($self) = @_; |
438 | my $next_evt = $self->parent_stream->next; |
439 | if ($self->selector_matches($next_evt)) { |
440 | return $self->apply_filter_to($next_evt); |
441 | } else { |
442 | return $next_evt; |
443 | } |
444 | } |
445 | |
446 | Internally, things are marginally more complicated than that, but not enough |
447 | that you as a user should normally need to care. |
448 | |
449 | In fact, an HTML::Zoom object is mostly just a container for the relevant |
450 | information from which to build the final stream that does the real work. A |
451 | stream built from a Zoom object is a stream of events from parsing the |
452 | initial HTML, wrapped in a filter stream per selector/filter pair provided |
453 | as described above. |
454 | |
455 | The upshot of this is that the application of filters works just as well on |
456 | streams as on the original Zoom object - in fact, when you run a |
457 | L</repeat_content> operation your subroutines are applied to the stream for |
458 | that element of the repeat, rather than constructing a new zoom per repeat |
459 | element as well. |
460 | |
461 | More concretely: |
462 | |
463 | $_->select('div')->replace_content('I AM A DIV!'); |
464 | |
465 | works on both HTML::Zoom objects themselves and HTML::Zoom stream objects and |
466 | shares sufficient of the implementation that you can generally forget the |
467 | difference - barring the fact that a stream already has state attached so |
468 | things like to_fh are no longer available. |
469 | |
470 | =head2 POP! GOES THE WEASEL |
471 | |
472 | ... and by Weasel, I mean layout. |
473 | |
474 | HTML::Zoom's filehandle object supports an additional event key, 'flush', |
475 | that is transparent to the rest of the system but indicates to the filehandle |
476 | object to end a getline operation at that point and return the HTML so far. |
477 | |
478 | This means that in an environment where streaming output is available, such |
479 | as a number of the L<Plack> PSGI handlers, you can add the flush key to an |
480 | event in order to ensure that the HTML generated so far is flushed through |
481 | to the browser right now. This can be especially useful if you know you're |
482 | about to call a web service or a potentially slow database query or similar |
483 | to ensure that at least the header/layout of your page renders now, improving |
484 | perceived user responsiveness while your application waits around for the |
485 | data it needs. |
486 | |
487 | This is currently exposed by the 'flush_before' option to the collect filter, |
488 | which incidentally also underlies the replace and repeat filters, so to |
489 | indicate we want this behaviour to happen before a query is executed we can |
490 | write something like: |
491 | |
492 | $zoom->select('.item')->repeat(sub { |
493 | if (my $row = $db_thing->next) { |
494 | return sub { $_->select('.item-name')->replace_content($row->name) } |
495 | } else { |
496 | return |
497 | } |
498 | }, { flush_before => 1 }); |
499 | |
500 | which should have the desired effect given a sufficiently lazy $db_thing (for |
501 | example a L<DBIx::Class::ResultSet> object). |
502 | |
503 | =head2 A FISTFUL OF OBJECTS |
504 | |
505 | At the core of an HTML::Zoom system lurks an L<HTML::Zoom::ZConfig> object, |
506 | whose purpose is to hang on to the various bits and pieces that things need |
507 | so that there's a common way of accessing shared functionality. |
508 | |
509 | Were I a computer scientist I would probably call this an "Inversion of |
510 | Control" object - which you'd be welcome to google to learn more about, or |
511 | you can just imagine a computer scientist being suspended upside down over |
512 | a pit. Either way works for me, I'm a pure maths grad. |
513 | |
514 | The ZConfig object hangs on to one each of the following for you: |
515 | |
516 | =over 4 |
517 | |
518 | =item * An HTML parser, normally L<HTML::Zoom::Parser::BuiltIn> |
519 | |
520 | =item * An HTML producer (emitter), normally L<HTML::Zoom::Producer::BuiltIn> |
521 | |
522 | =item * An object to build event filters, normally L<HTML::Zoom::FilterBuilder> |
523 | |
524 | =item * An object to parse CSS selectors, normally L<HTML::Zoom::SelectorParser> |
525 | |
526 | =item * An object to build streams, normally L<HTML::Zoom::StreamUtils> |
527 | |
528 | =back |
529 | |
530 | In theory you could replace any of these with anything you like, but in |
531 | practice you're probably best restricting yourself to subclasses, or at |
532 | least things that manage to look like the original if you squint a bit. |
533 | |
534 | If you do something more clever than that, or find yourself overriding things |
535 | in your ZConfig a lot, please please tell us about it via one of the means |
536 | mentioned under L</SUPPORT>. |
537 | |
538 | =head2 SEMANTIC DIDACTIC |
539 | |
540 | Some will argue that overloading CSS selectors to do data stuff is a terrible |
541 | idea, and possibly even a step towards the "Concrete Javascript" pattern |
542 | (which I abhor) or Smalltalk's Morphic (which I ignore, except for the part |
543 | where it keeps reminding me of the late, great Tony Hart's plasticine friend). |
544 | |
545 | To which I say, "eh", "meh", and possibly also "feh". If it really upsets |
546 | you, either use extra classes for this (and remove them afterwards) or |
547 | use special fake elements or, well, honestly, just use something different. |
548 | L<Template::Semantic> provides a similar idea to zoom except using XPath |
549 | and XML::LibXML transforms rather than a lightweight streaming approach - |
550 | maybe you'd like that better. Or maybe you really did want |
551 | L<Template Toolkit|Template> after all. It is still damn good at what it does, |
552 | after all. |
553 | |
554 | So far, however, I've found that for new sites the designers I'm working with |
555 | generally want to produce nice semantic HTML with classes that represent the |
556 | nature of the data rather than the structure of the layout, so sharing them |
557 | as a common interface works really well for us. |
558 | |
559 | In the absence of any evidence that overloading CSS selectors has killed |
560 | children or unexpectedly set fire to grandmothers - and given microformats |
561 | have been around for a while there's been plenty of opportunity for |
562 | octagenarian combustion - I'd suggest you give it a try and see if you like it. |
563 | |
564 | =head2 GET THEE TO A SUMMARY! |
565 | |
566 | Erm. Well. |
567 | |
568 | HTML::Zoom is a lazy, stream oriented, streaming capable, mostly functional, |
569 | CSS selector based semantic templating engine for HTML and HTML-like |
570 | document formats. |
571 | |
572 | But I said that already. Although hopefully by now you have some idea what I |
573 | meant when I said it. If you didn't have any idea the first time. I mean, I'm |
574 | not trying to call you stupid or anything. Just saying that maybe it wasn't |
575 | totally obvious without the explanation. Or something. |
576 | |
577 | Er. |
578 | |
579 | Maybe we should just move on to the method docs. |
580 | |
581 | =head1 METHODS |
582 | |
583 | =head2 new |
584 | |
585 | my $zoom = HTML::Zoom->new; |
586 | |
587 | my $zoom = HTML::Zoom->new({ zconfig => $zconfig }); |
588 | |
589 | Create a new empty Zoom object. You can optionally pass an |
590 | L<HTML::Zoom::ZConfig> instance if you're trying to override one or more of |
591 | the default components. |
592 | |
593 | This method isn't often used directly since several other methods can also |
594 | act as constructors, notable L</select> and L</from_html> |
595 | |
596 | =head2 zconfig |
597 | |
598 | my $zconfig = $zoom->zconfig; |
599 | |
600 | Retrieve the L<HTML::Zoom::ZConfig> instance used by this Zoom object. You |
601 | shouldn't usually need to call this yourself. |
602 | |
603 | =head2 from_html |
604 | |
605 | my $zoom = HTML::Zoom->from_html($html); |
606 | |
607 | my $z2 = $z1->from_html($html); |
608 | |
609 | Parses the HTML using the current zconfig's parser object and returns a new |
610 | zoom instance with that as the source HTML to be transformed. |
611 | |
612 | =head2 from_file |
613 | |
614 | my $zoom = HTML::Zoom->from_file($file); |
615 | |
616 | my $z2 = $z1->from_file($file); |
617 | |
618 | Convenience method - slurps the contents of $file and calls from_html with it. |
619 | |
620 | =head2 to_stream |
621 | |
622 | my $stream = $zoom->to_stream; |
623 | |
624 | while (my ($evt) = $stream->next) { |
625 | ... |
626 | |
627 | Creates a stream, starting with a stream of the events from the HTML supplied |
628 | via L</from_html> and then wrapping it in turn with each selector+filter pair |
629 | that have been applied to the zoom object. |
630 | |
631 | =head2 to_fh |
632 | |
633 | my $fh = $zoom->to_fh; |
634 | |
635 | call_something_expecting_a_filehandle($fh); |
636 | |
637 | Returns an L<HTML::Zoom::ReadFH> instance that will create a stream the first |
638 | time its getline method is called and then return all HTML up to the next |
639 | event with 'flush' set. |
640 | |
641 | You can pass this filehandle to compliant PSGI handlers (and probably most |
642 | web frameworks). |
643 | |
644 | =head2 run |
645 | |
646 | $zoom->run; |
647 | |
648 | Runs the zoom object's transforms without doing anything with the results. |
649 | |
650 | Normally used to get side effects of a zoom run - for example when using |
651 | L<HTML::Zoom::FilterBuilder/collect> to slurp events for scraping or layout. |
652 | |
653 | =head2 apply |
654 | |
655 | my $z2 = $z1->apply(sub { |
656 | $_->select('div')->replace_content('I AM A DIV!') }) |
657 | }); |
658 | |
659 | Sets $_ to the zoom object and then runs the provided code. Basically syntax |
660 | sugar, the following is entirely equivalent: |
661 | |
662 | my $sub = sub { |
663 | shift->select('div')->replace_content('I AM A DIV!') }) |
664 | }; |
665 | |
666 | my $z2 = $sub->($z1); |
667 | |
668 | =head2 to_html |
669 | |
670 | my $html = $zoom->to_html; |
671 | |
672 | Runs the zoom processing and returns the resulting HTML. |
673 | |
674 | =head2 memoize |
675 | |
676 | my $z2 = $z1->memoize; |
677 | |
678 | Creates a new zoom whose source HTML is the results of the original zoom's |
679 | processing. Effectively syntax sugar for: |
680 | |
681 | my $z2 = HTML::Zoom->from_html($z1->to_html); |
682 | |
683 | but preserves your L<HTML::Zoom::ZConfig> object. |
684 | |
685 | =head2 with_filter |
686 | |
687 | my $zoom = HTML::Zoom->with_filter( |
688 | 'div', $filter_builder->replace_content('I AM A DIV!') |
689 | ); |
690 | |
691 | my $z2 = $z1->with_filter( |
692 | 'div', $filter_builder->replace_content('I AM A DIV!') |
693 | ); |
694 | |
695 | Lower level interface than L</select> to adding filters to your zoom object. |
696 | |
697 | In normal usage, you probably don't need to call this yourself. |
698 | |
699 | =head2 select |
700 | |
701 | my $zoom = HTML::Zoom->select('div')->replace_content('I AM A DIV!'); |
702 | |
703 | my $z2 = $z1->select('div')->replace_content('I AM A DIV!'); |
704 | |
97192b02 |
705 | Returns an intermediary object of the class L<HTML::Zoom::TransformBuilder> |
1c4455ae |
706 | on which methods of your L<HTML::Zoom::FilterBuilder> object can be called. |
707 | |
708 | In normal usage you should generally always put the pair of method calls |
709 | together; the intermediary object isn't designed or expected to stick around. |
710 | |
711 | =head2 then |
712 | |
2daa653a |
713 | my $z2 = $z1->select('div')->add_to_attribute(class => 'spoon') |
1c4455ae |
714 | ->then |
715 | ->replace_content('I AM A DIV!'); |
716 | |
717 | Re-runs the previous select to allow you to chain actions together on the |
718 | same selector. |
719 | |
f107bef7 |
720 | =head1 AUTHOR |
45b4cea1 |
721 | |
f107bef7 |
722 | mst - Matt S. Trout (cpan:MSTROUT) <mst@shadowcat.co.uk> |
45b4cea1 |
723 | |
f107bef7 |
724 | =head1 CONTRIBUTORS |
45b4cea1 |
725 | |
f107bef7 |
726 | Oliver Charles |
727 | |
728 | Jakub Nareski |
729 | |
730 | Simon Elliot |
731 | |
732 | Joe Highton |
733 | |
734 | John Napiorkowski |
735 | |
5cac799e |
736 | Robert Buels |
737 | |
f107bef7 |
738 | =head1 COPYRIGHT |
739 | |
740 | Copyright (c) 2010-2011 the HTML::Zoom L</AUTHOR> and L</CONTRIBUTORS> |
741 | as listed above. |
45b4cea1 |
742 | |
743 | =head1 LICENSE |
744 | |
745 | This library is free software, you can redistribute it and/or modify |
746 | it under the same terms as Perl itself. |
747 | |
d80786d0 |
748 | =cut |
45b4cea1 |
749 | |