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