1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
|
require 'action_view/helpers/tag_helper'
require 'html/document'
module ActionView
module Helpers #:nodoc:
# The TextHelper Module provides a set of methods for filtering, formatting
# and transforming strings that can reduce the amount of inline Ruby code in
# your views. These helper methods extend ActionView making them callable
# within your template files as shown in the following example which truncates
# the title of each post to 10 characters.
#
# <% @posts.each do |post| %>
# # post == 'This is my title'
# Title: <%= truncate(post.title, 10) %>
# <% end %>
# => Title: This is my...
module TextHelper
# The preferred method of outputting text in your views is to use the
# <%= "text" %> eRuby syntax. The regular _puts_ and _print_ methods
# do not operate as expected in an eRuby code block. If you absolutely must
# output text within a code block, you can use the concat method.
#
# <% concat "hello", binding %>
# is equivalent to using:
# <%= "hello" %>
def concat(string, binding)
eval(ActionView::Base.erb_variable, binding) << string
end
# If +text+ is longer than +length+, +text+ will be truncated to the length of
# +length+ and the last three characters will be replaced with the +truncate_string+.
#
# truncate("Once upon a time in a world far far away", 14)
# => Once upon a...
def truncate(text, length = 30, truncate_string = "...")
if text.nil? then return end
l = length - truncate_string.chars.length
text.chars.length > length ? text.chars[0...l] + truncate_string : text
end
# Highlights +phrase+ everywhere it is found in +text+ by inserting it into
# a +highlighter+ string. The highlighter can be specialized by passing +highlighter+
# as a single-quoted string with \1 where the phrase is to be inserted.
#
# highlight('You searched for: rails', 'rails')
# => You searched for: <strong class="highlight">rails</strong>
def highlight(text, phrase, highlighter = '<strong class="highlight">\1</strong>')
if phrase.blank? then return text end
text.gsub(/(#{Regexp.escape(phrase)})/i, highlighter) unless text.nil?
end
# Extracts an excerpt from +text+ that matches the first instance of +phrase+.
# The +radius+ expands the excerpt on each side of +phrase+ by the number of characters
# defined in +radius+. If the excerpt radius overflows the beginning or end of the +text+,
# then the +excerpt_string+ will be prepended/appended accordingly. If the +phrase+
# isn't found, nil is returned.
#
# excerpt('This is an example', 'an', 5)
# => "...s is an examp..."
#
# excerpt('This is an example', 'is', 5)
# => "This is an..."
def excerpt(text, phrase, radius = 100, excerpt_string = "...")
if text.nil? || phrase.nil? then return end
phrase = Regexp.escape(phrase)
if found_pos = text.chars =~ /(#{phrase})/i
start_pos = [ found_pos - radius, 0 ].max
end_pos = [ found_pos + phrase.chars.length + radius, text.chars.length ].min
prefix = start_pos > 0 ? excerpt_string : ""
postfix = end_pos < text.chars.length ? excerpt_string : ""
prefix + text.chars[start_pos..end_pos].strip + postfix
else
nil
end
end
# Attempts to pluralize the +singular+ word unless +count+ is 1. If +plural+
# is supplied, it will use that when count is > 1, if the ActiveSupport Inflector
# is loaded, it will use the Inflector to determine the plural form, otherwise
# it will just add an 's' to the +singular+ word.
#
# pluralize(1, 'person') => 1 person
# pluralize(2, 'person') => 2 people
# pluralize(3, 'person', 'users') => 3 users
def pluralize(count, singular, plural = nil)
"#{count || 0} " + if count == 1 || count == '1'
singular
elsif plural
plural
elsif Object.const_defined?("Inflector")
Inflector.pluralize(singular)
else
singular + "s"
end
end
# Wraps the +text+ into lines no longer than +line_width+ width. This method
# breaks on the first whitespace character that does not exceed +line_width+.
#
# word_wrap('Once upon a time', 4)
# => Once\nupon\na\ntime
def word_wrap(text, line_width = 80)
text.gsub(/\n/, "\n\n").gsub(/(.{1,#{line_width}})(\s+|$)/, "\\1\n").strip
end
begin
require_library_or_gem "redcloth" unless Object.const_defined?(:RedCloth)
# Returns the text with all the Textile codes turned into HTML tags.
# <i>This method is only available if RedCloth[http://whytheluckystiff.net/ruby/redcloth/]
# is available</i>.
def textilize(text)
if text.blank?
""
else
textilized = RedCloth.new(text, [ :hard_breaks ])
textilized.hard_breaks = true if textilized.respond_to?("hard_breaks=")
textilized.to_html
end
end
# Returns the text with all the Textile codes turned into HTML tags,
# but without the bounding <p> tag that RedCloth adds.
# <i>This method is only available if RedCloth[http://whytheluckystiff.net/ruby/redcloth/]
# is available</i>.
def textilize_without_paragraph(text)
textiled = textilize(text)
if textiled[0..2] == "<p>" then textiled = textiled[3..-1] end
if textiled[-4..-1] == "</p>" then textiled = textiled[0..-5] end
return textiled
end
rescue LoadError
# We can't really help what's not there
end
begin
require_library_or_gem "bluecloth" unless Object.const_defined?(:BlueCloth)
# Returns the text with all the Markdown codes turned into HTML tags.
# <i>This method is only available if BlueCloth[http://www.deveiate.org/projects/BlueCloth]
# is available</i>.
def markdown(text)
text.blank? ? "" : BlueCloth.new(text).to_html
end
rescue LoadError
# We can't really help what's not there
end
# Returns +text+ transformed into HTML using simple formatting rules.
# Two or more consecutive newlines(<tt>\n\n</tt>) are considered as a
# paragraph and wrapped in <tt><p></tt> tags. One newline (<tt>\n</tt>) is
# considered as a linebreak and a <tt><br /></tt> tag is appended. This
# method does not remove the newlines from the +text+.
def simple_format(text)
content_tag 'p', text.to_s.
gsub(/\r\n?/, "\n"). # \r\n and \r -> \n
gsub(/\n\n+/, "</p>\n\n<p>"). # 2+ newline -> paragraph
gsub(/([^\n]\n)(?=[^\n])/, '\1<br />') # 1 newline -> br
end
# Turns all urls and email addresses into clickable links. The +link+ parameter
# will limit what should be linked. You can add html attributes to the links using
# +href_options+. Options for +link+ are <tt>:all</tt> (default),
# <tt>:email_addresses</tt>, and <tt>:urls</tt>.
#
# auto_link("Go to http://www.rubyonrails.org and say hello to david@loudthinking.com") =>
# Go to <a href="http://www.rubyonrails.org">http://www.rubyonrails.org</a> and
# say hello to <a href="mailto:david@loudthinking.com">david@loudthinking.com</a>
#
# If a block is given, each url and email address is yielded and the
# result is used as the link text.
#
# auto_link(post.body, :all, :target => '_blank') do |text|
# truncate(text, 15)
# end
def auto_link(text, link = :all, href_options = {}, &block)
return '' if text.blank?
case link
when :all then auto_link_urls(auto_link_email_addresses(text, &block), href_options, &block)
when :email_addresses then auto_link_email_addresses(text, &block)
when :urls then auto_link_urls(text, href_options, &block)
end
end
# Strips link tags from +text+ leaving just the link label.
#
# strip_links('<a href="http://www.rubyonrails.org">Ruby on Rails</a>')
# => Ruby on Rails
def strip_links(text)
text.gsub(/<a\b.*?>(.*?)<\/a>/mi, '\1')
end
VERBOTEN_TAGS = %w(form script plaintext) unless defined?(VERBOTEN_TAGS)
VERBOTEN_ATTRS = /^on/i unless defined?(VERBOTEN_ATTRS)
# Sanitizes the +html+ by converting <form> and <script> tags into regular
# text, and removing all "onxxx" attributes (so that arbitrary Javascript
# cannot be executed). It also removes href= and src= attributes that start with
# "javascript:". You can modify what gets sanitized by defining VERBOTEN_TAGS
# and VERBOTEN_ATTRS before this Module is loaded.
#
# sanitize('<script> do_nasty_stuff() </script>')
# => <script> do_nasty_stuff() </script>
# sanitize('<a href="javascript: sucker();">Click here for $100</a>')
# => <a>Click here for $100</a>
def sanitize(html)
# only do this if absolutely necessary
if html.index("<")
tokenizer = HTML::Tokenizer.new(html)
new_text = ""
while token = tokenizer.next
node = HTML::Node.parse(nil, 0, 0, token, false)
new_text << case node
when HTML::Tag
if VERBOTEN_TAGS.include?(node.name)
node.to_s.gsub(/</, "<")
else
if node.closing != :close
node.attributes.delete_if { |attr,v| attr =~ VERBOTEN_ATTRS }
%w(href src).each do |attr|
node.attributes.delete attr if node.attributes[attr] =~ /^javascript:/i
end
end
node.to_s
end
else
node.to_s.gsub(/</, "<")
end
end
html = new_text
end
html
end
# Strips all HTML tags from the +html+, including comments. This uses the
# html-scanner tokenizer and so its HTML parsing ability is limited by
# that of html-scanner.
def strip_tags(html)
return html if html.blank?
if html.index("<")
text = ""
tokenizer = HTML::Tokenizer.new(html)
while token = tokenizer.next
node = HTML::Node.parse(nil, 0, 0, token, false)
# result is only the content of any Text nodes
text << node.to_s if node.class == HTML::Text
end
# strip any comments, and if they have a newline at the end (ie. line with
# only a comment) strip that too
text.gsub(/<!--(.*?)-->[\n]?/m, "")
else
html # already plain text
end
end
# Creates a Cycle object whose _to_s_ method cycles through elements of an
# array every time it is called. This can be used for example, to alternate
# classes for table rows:
#
# <% @items.each do |item| %>
# <tr class="<%= cycle("even", "odd") -%>">
# <td>item</td>
# </tr>
# <% end %>
#
# You can use named cycles to allow nesting in loops. Passing a Hash as
# the last parameter with a <tt>:name</tt> key will create a named cycle.
# You can manually reset a cycle by calling reset_cycle and passing the
# name of the cycle.
#
# <% @items.each do |item| %>
# <tr class="<%= cycle("even", "odd", :name => "row_class")
# <td>
# <% item.values.each do |value| %>
# <span style="color:<%= cycle("red", "green", "blue", :name => "colors") -%>">
# value
# </span>
# <% end %>
# <% reset_cycle("colors") %>
# </td>
# </tr>
# <% end %>
def cycle(first_value, *values)
if (values.last.instance_of? Hash)
params = values.pop
name = params[:name]
else
name = "default"
end
values.unshift(first_value)
cycle = get_cycle(name)
if (cycle.nil? || cycle.values != values)
cycle = set_cycle(name, Cycle.new(*values))
end
return cycle.to_s
end
# Resets a cycle so that it starts from the first element the next time
# it is called. Pass in +name+ to reset a named cycle.
def reset_cycle(name = "default")
cycle = get_cycle(name)
cycle.reset unless cycle.nil?
end
class Cycle #:nodoc:
attr_reader :values
def initialize(first_value, *values)
@values = values.unshift(first_value)
reset
end
def reset
@index = 0
end
def to_s
value = @values[@index].to_s
@index = (@index + 1) % @values.size
return value
end
end
private
# The cycle helpers need to store the cycles in a place that is
# guaranteed to be reset every time a page is rendered, so it
# uses an instance variable of ActionView::Base.
def get_cycle(name)
@_cycles = Hash.new unless defined?(@_cycles)
return @_cycles[name]
end
def set_cycle(name, cycle_object)
@_cycles = Hash.new unless defined?(@_cycles)
@_cycles[name] = cycle_object
end
AUTO_LINK_RE = %r{
( # leading text
<\w+.*?>| # leading HTML tag, or
[^=!:'"/]| # leading punctuation, or
^ # beginning of line
)
(
(?:https?://)| # protocol spec, or
(?:www\.) # www.*
)
(
[-\w]+ # subdomain or domain
(?:\.[-\w]+)* # remaining subdomains or domain
(?::\d+)? # port
(?:/(?:(?:[~\w\+%-]|(?:[,.;:][^\s$]))+)?)* # path
(?:\?[\w\+%&=.;-]+)? # query string
(?:\#[\w\-]*)? # trailing anchor
)
([[:punct:]]|\s|<|$) # trailing text
}x unless const_defined?(:AUTO_LINK_RE)
# Turns all urls into clickable links. If a block is given, each url
# is yielded and the result is used as the link text.
def auto_link_urls(text, href_options = {})
extra_options = tag_options(href_options.stringify_keys) || ""
text.gsub(AUTO_LINK_RE) do
all, a, b, c, d = $&, $1, $2, $3, $4
if a =~ /<a\s/i # don't replace URL's that are already linked
all
else
text = b + c
text = yield(text) if block_given?
%(#{a}<a href="#{b=="www."?"http://www.":b}#{c}"#{extra_options}>#{text}</a>#{d})
end
end
end
# Turns all email addresses into clickable links. If a block is given,
# each email is yielded and the result is used as the link text.
def auto_link_email_addresses(text)
text.gsub(/([\w\.!#\$%\-+.]+@[A-Za-z0-9\-]+(\.[A-Za-z0-9\-]+)+)/) do
text = $1
text = yield(text) if block_given?
%{<a href="mailto:#{$1}">#{text}</a>}
end
end
end
end
end
|