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