Module: TextUtils::HypertextHelper

Defined in:
lib/textutils/helper/hypertext_helper.rb

Instance Method Summary collapse

Instance Method Details

#content_tag(tag, content, opts = {}) ⇒ Object

content tag (e.g. <p>hello</p> - w/ opening and closing tag)



137
138
139
140
141
142
143
144
145
146
147
148
 
# File 'lib/textutils/helper/hypertext_helper.rb', line 137

def content_tag( tag, content, opts={} ) # content tag (e.g. <p>hello</p> - w/ opening and closing tag)
  attribs = []
  opts.each do |key,value|
    attribs << "#{key}='#{value}'"
  end
  
  if attribs.size > 0
    "<#{tag} #{attribs.join(' ')}>#{content}</#{tag}>"
  else
    "<#{tag}>#{content}</#{tag}>"
  end
end

#image_tag(src, opts = {}) ⇒ Object 



160
161
162
163
164
 
# File 'lib/textutils/helper/hypertext_helper.rb', line 160

def image_tag( src, opts={} )
  attribs = { src: src }
  attribs = attribs.merge( opts )  ### fix/todo: use reverse merge e.g. overwrite only if not present
  tag( :img, attribs )   ### "<img src='#{src}' #{attributes}>"
end

#link_to(content, href, opts = {}) ⇒ Object 



166
167
168
169
170
 
# File 'lib/textutils/helper/hypertext_helper.rb', line 166

def link_to( content, href, opts={} )
  attribs = { href: href }
  attribs = attribs.merge( opts )  ### fix/todo: use reverse merge e.g. overwrite only if not present
  content_tag( :a, content, attribs )  ### "<a href='#{href}' #{attributes}>#{text}</a>"
end

#sanitize(ht, opts = {}) ⇒ Object

change to simple_hypertext or

hypertext_simple or
sanitize ???



79
80
81
82
83
84
85
86
87
88
 
# File 'lib/textutils/helper/hypertext_helper.rb', line 79

def sanitize( ht, opts={} )  # ht -> hypertext
  # todo: add options for
  #   keep links, images, lists (?too), code, codeblocks

  ht = whitelist( ht, [:br, :p, :ul, :ol, :li, :pre, :code, :blockquote, :q, :cite], opts )

# clean (prettify) literal urls (strip protocoll) 
  ht = ht.gsub( /(http|https):\/\//, '' )
  ht
end

#strip_tags(ht) ⇒ Object 



7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
 
# File 'lib/textutils/helper/hypertext_helper.rb', line 7

def strip_tags( ht )
  ### to be done
  ## strip markup tags; return plain text; use brute force for now
  # check at least for presence of required a-z+ tag names
  
  ### ht.gsub( /<[^>]+>/, '' ) - old simple

  ## todo: add strip comments e.g. <!-- xxxx --> ???
  ##  or use new strip_comments( ht )

  ht = ht.gsub( /<([a-z]+)\s*\/>/i, '' )       # remove xml-style empty tags eg. <br /> or <br/>
  ht = ht.gsub( /<([a-z]+)(\s+[^>]*)?>/i, '' ) # opening tag <p>
  ht = ht.gsub( /<\/([a-z]+)\s*>/i, '' )       # closing tag e.g. </p>
  ht
end

#stylesheet_link_tag(href, opts = {}) ⇒ Object 



151
152
153
154
155
156
157
158
 
# File 'lib/textutils/helper/hypertext_helper.rb', line 151

def stylesheet_link_tag( href, opts={} )
  href = "#{href}.css"  unless href.end_with?( '.css' )   # auto-add .css if not present
  attribs = { rel:  'stylesheet',
              type: 'text/css',
              href: href }
  attribs = attribs.merge( opts )  ### fix/todo: use reverse merge e.g. overwrite only if not present
  tag( :link, attribs )
end

#tag(tag, opts = {}) ⇒ Object

rails-style asset, url tag helpers and friends

todo:  move into different helper module/modules?? why? why not?



124
125
126
127
128
129
130
131
132
133
134
135
 
# File 'lib/textutils/helper/hypertext_helper.rb', line 124

def tag( tag, opts={} )  # empty tag (no content e.g. <br>, <img src=''> etc.)
  attribs  = []
  opts.each do |key,value|
    attribs << "#{key}='#{value}'"
  end
  
  if attribs.size > 0
    "<#{tag} #{attribs.join(' ')}>"
  else
    "<#{tag}>"
  end
end

#textify(ht, opts = {}) ⇒ Object

ht -> hypertext



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
 
# File 'lib/textutils/helper/hypertext_helper.rb', line 91

def textify( ht, opts={} )   # ht -> hypertext
  ## turn into plain (or markdown/wiki-style) text - to be done

  sanitize( ht, opts )   # step 1 - sanitize html
  # to be done

# strip bold
#    ht = ht.gsub( /<b[^>]*>/, '**' )  # fix: will also swallow bxxx tags - add b space
#    ht = ht.gsub( /<\/b>/, '**' )

# strip em
#   ht = ht.gsub( /<em[^>]*>/, '__' )
#   ht = ht.gsub( /<\/em>/, '__' )

#    ht = ht.gsub( /&nbsp;/, ' ' )

#    # try to cleanup whitespaces
#    # -- keep no more than two spaces
#    ht = ht.gsub( /[ \t]{3,}/, '  ' )
#    # -- keep no more than two new lines
#    ht = ht.gsub( /\n{2,}/m, "\n\n" ) 
#    # -- remove all trailing spaces
#    ht = ht.gsub( /[ \t\n]+$/m, '' )
#    # -- remove all leading spaces
#    ht = ht.gsub( /^[ \t\n]+/m, '' )
end

#whitelist(ht, tags, opts = {}) ⇒ Object 



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
 
# File 'lib/textutils/helper/hypertext_helper.rb', line 24

def whitelist( ht, tags, opts={} )

  # note: assumes properly escaped <> in ht/hypertext

  ###############################################
  # step one - save whitelisted tags use ‹tag›
  tags.each do |tag|
    # note: we strip all attribues
    # note: match all tags case insensitive e.g. allow a,A or br,BR,bR etc.
    #   downcase all tags

    # convert xml-style empty tags to simple html emtpty tags
    #  e.g. <br/> or <br /> becomses <br>
    ht = ht.gsub( /<(#{tag})\s*\/>/i )       { |_| "‹#{$1.downcase}›" }   # eg. <br /> or <br/> becomes ‹br›

    # make sure we won't swall <br> for <b> for example, thus use \s+ before [^>]
    ht = ht.gsub( /<(#{tag})(\s+[^>]*)?>/i ) { |_| "‹#{$1.downcase}›" }   # opening tag <p>
    ht = ht.gsub( /<\/(#{tag})\s*>/i )       { |_| "‹/#{$1.downcase}›" }  # closing tag e.g. </p>
  end

  ############################
  # step two - clean tags

  #   strip images - special treatment for debugging
  ht = ht.gsub( /<img[^>]*>/i, '♦' )   # for debugging use black diamond e.g. ♦
  ht = ht.gsub( /<\/img>/i, '' )   # should not exists

  # strip all remaining tags
  #  -- note: will NOT strip comments for now e.g. <!-- -->
  ht = strip_tags( ht )

  pp ht  # fix: debugging indo - remove
    
  ############################################
  # step three - restore whitelisted tags

  return ht   if opts[:skip_restore]   # skip step 3 for debugging

  tags.each do |tag|
#      ht = ht.gsub( /‹(#{tag})›/, "<\1>" )  # opening tag e.g. <p>
#      ht = ht.gsub( /‹\/(#{tag})›/, "<\/\1>" )  # closing tag e.g. </p>
    ht = ht.gsub( /‹(#{tag})›/ )   { |_| "<#{$1}>" }
    ht = ht.gsub( /‹\/(#{tag})›/ ) { |_| "<\/#{$1}>" }  # closing tag e.g. </p>
  end

  ht
end