aboutsummaryrefslogtreecommitdiffstats
path: root/railties/guides/rails_guides/generator.rb
blob: eee7fb26374fc6c827902c12dd403736f673f525 (plain) (blame)
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
# ---------------------------------------------------------------------------
#
# This script generates the guides. It can be invoked either directly or via the
# generate_guides rake task within the railties directory.
#
# Guides are taken from the source directory, and the resulting HTML goes into the
# output directory. Assets are stored under files, and copied to output/files as
# part of the generation process.
#
# Some arguments may be passed via environment variables:
#
#   WARNINGS
#     If you are writing a guide, please work always with WARNINGS=1. Users can
#     generate the guides, and thus this flag is off by default.
#
#     Internal links (anchors) are checked. If a reference is broken levenshtein
#     distance is used to suggest an existing one. This is useful since IDs are
#     generated by Textile from headers and thus edits alter them.
#
#     Also detects duplicated IDs. They happen if there are headers with the same
#     text. Please do resolve them, if any, so guides are valid XHTML.
#
#   ALL
#    Set to "1" to force the generation of all guides.
#
#   ONLY
#     Use ONLY if you want to generate only one or a set of guides. Prefixes are
#     enough:
#
#       # generates only association_basics.html
#       ONLY=assoc ruby rails_guides.rb
#
#     Separate many using commas:
#
#       # generates only association_basics.html and migrations.html
#       ONLY=assoc,migrations ruby rails_guides.rb
#
#     Note that if you are working on a guide generation will by default process
#     only that one, so ONLY is rarely used nowadays.
#
#   GUIDES_LANGUAGE
#     Use GUIDES_LANGUAGE when you want to generate translated guides in
#     <tt>source/<GUIDES_LANGUAGE></tt> folder (such as <tt>source/es</tt>).
#     Ignore it when generating English guides.
#
#   EDGE
#     Set to "1" to indicate generated guides should be marked as edge. This
#     inserts a badge and changes the preamble of the home page.
#
#   KINDLE
#     Set to "1" to generate the .mobi with all the guides. The kindlegen
#     executable must be in your PATH. You can get it for free from
#     http://www.amazon.com/kindlepublishing
#
# ---------------------------------------------------------------------------

require 'set'
require 'fileutils'

require 'active_support/core_ext/string/output_safety'
require 'active_support/core_ext/object/blank'
require 'action_controller'
require 'action_view'

require 'rails_guides/indexer'
require 'rails_guides/helpers'
require 'rails_guides/levenshtein'

module RailsGuides
  class Generator
    attr_reader :guides_dir, :source_dir, :output_dir, :edge, :warnings, :all

    GUIDES_RE = /\.(?:textile|erb)$/

    def initialize(output=nil)
      set_flags_from_environment

      if kindle?
        check_for_kindlegen
        register_kindle_mime_types
      end

      initialize_dirs(output)
      create_output_dir_if_needed
    end

    def set_flags_from_environment
      @edge     = ENV['EDGE']     == '1'
      @warnings = ENV['WARNINGS'] == '1'
      @all      = ENV['ALL']      == '1'
      @kindle   = ENV['KINDLE']   == '1'
      @version  = ENV['RAILS_VERSION'] || `git rev-parse --short HEAD`.chomp
      @lang     = ENV['GUIDES_LANGUAGE']
    end

    def register_kindle_mime_types
      Mime::Type.register_alias("application/xml", :opf, %w(opf))
      Mime::Type.register_alias("application/xml", :ncx, %w(ncx))
    end

    def generate
      generate_guides
      copy_assets
      generate_mobi if kindle?
    end

    private

    def kindle?
      @kindle
    end

    def check_for_kindlegen
      if `which kindlegen`.blank?
        raise "Can't create a kindle version without `kindlegen`."
      end
    end

    def generate_mobi
      opf = "#{output_dir}/rails_guides.opf"
      out = "#{output_dir}/kindlegen.out"

      system "kindlegen #{opf} -o #{mobi} > #{out} 2>&1"
      puts "Guides compiled as Kindle book to #{mobi}"
      puts "(kindlegen log at #{out})."
    end

    def mobi
      "ruby_on_rails_guides_#@version%s.mobi" % (@lang.present? ? ".#@lang" : '')
    end

    def initialize_dirs(output)
      @guides_dir = File.join(File.dirname(__FILE__), '..')
      @source_dir = "#@guides_dir/source/#@lang"
      @output_dir = if output
        output
      elsif kindle?
        "#@guides_dir/output/kindle/#@lang"
      else
        "#@guides_dir/output/#@lang"
      end.sub(%r</$>, '')
    end

    def create_output_dir_if_needed
      FileUtils.mkdir_p(output_dir)
    end

    def generate_guides
      guides_to_generate.each do |guide|
        output_file = output_file_for(guide)
        generate_guide(guide, output_file) if generate?(guide, output_file)
      end
    end

    def guides_to_generate
      guides = Dir.entries(source_dir).grep(GUIDES_RE)

      if kindle?
        Dir.entries("#{source_dir}/kindle").grep(GUIDES_RE).map do |entry|
          guides << "kindle/#{entry}"
        end
      end

      ENV.key?('ONLY') ? select_only(guides) : guides
    end

    def select_only(guides)
      prefixes = ENV['ONLY'].split(",").map(&:strip)
      guides.select do |guide|
        prefixes.any? {|p| guide.start_with?(p)}
      end
    end

    def copy_assets
      FileUtils.cp_r(Dir.glob("#{guides_dir}/assets/*"), output_dir)
    end

    def output_file_for(guide)
      if guide =~/\.textile$/
        guide.sub(/\.textile$/, '.html')
      else
        guide.sub(/\.erb$/, '')
      end
    end

    def output_path_for(output_file)
      File.join(output_dir, File.basename(output_file))
    end

    def generate?(source_file, output_file)
      fin  = File.join(source_dir, source_file)
      fout = output_path_for(output_file)
      all || !File.exists?(fout) || File.mtime(fout) < File.mtime(fin)
    end

    def generate_guide(guide, output_file)
      output_path = output_path_for(output_file)
      puts "Generating #{guide} as #{output_file}"
      layout = kindle? ? 'kindle/layout' : 'layout'

      File.open(output_path, 'w') do |f|
        view = ActionView::Base.new(source_dir, :edge => @edge, :version => @version, :mobi => "kindle/#{mobi}")
        view.extend(Helpers)

        if guide =~ /\.(\w+)\.erb$/
          # Generate the special pages like the home.
          # Passing a template handler in the template name is deprecated. So pass the file name without the extension.
          result = view.render(:layout => layout, :formats => [$1], :file => $`)
        else
          body = File.read(File.join(source_dir, guide))
          body = set_header_section(body, view)
          body = set_index(body, view)

          result = view.render(:layout => layout, :text => textile(body))

          warn_about_broken_links(result) if @warnings
        end

        f.write(result)
      end
    end

    def set_header_section(body, view)
      new_body = body.gsub(/(.*?)endprologue\./m, '').strip
      header = $1

      header =~ /h2\.(.*)/
      page_title = "Ruby on Rails Guides: #{$1.strip}"

      header = textile(header)

      view.content_for(:page_title) { page_title.html_safe }
      view.content_for(:header_section) { header.html_safe }
      new_body
    end

    def set_index(body, view)
      index = <<-INDEX
      <div id="subCol">
        <h3 class="chapter"><img src="images/chapters_icon.gif" alt="" />Chapters</h3>
        <ol class="chapters">
      INDEX

      i = Indexer.new(body, warnings)
      i.index

      # Set index for 2 levels
      i.level_hash.each do |key, value|
        link = view.content_tag(:a, :href => key[:id]) { textile(key[:title], true).html_safe }

        children = value.keys.map do |k|
          view.content_tag(:li,
            view.content_tag(:a, :href => k[:id]) { textile(k[:title], true).html_safe })
        end

        children_ul = children.empty? ? "" : view.content_tag(:ul, children.join(" ").html_safe)

        index << view.content_tag(:li, link.html_safe + children_ul.html_safe)
      end

      index << '</ol>'
      index << '</div>'

      view.content_for(:index_section) { index.html_safe }

      i.result
    end

    def textile(body, lite_mode=false)
      t = RedCloth.new(body)
      t.hard_breaks = false
      t.lite_mode = lite_mode
      t.to_html(:notestuff, :plusplus, :code)
    end

    def warn_about_broken_links(html)
      anchors = extract_anchors(html)
      check_fragment_identifiers(html, anchors)
    end

    def extract_anchors(html)
      # Textile generates headers with IDs computed from titles.
      anchors = Set.new
      html.scan(/<h\d\s+id="([^"]+)/).flatten.each do |anchor|
        if anchors.member?(anchor)
          puts "*** DUPLICATE ID: #{anchor}, please put and explicit ID, e.g. h4(#explicit-id), or consider rewording"
        else
          anchors << anchor
        end
      end

      # Footnotes.
      anchors += Set.new(html.scan(/<p\s+class="footnote"\s+id="([^"]+)/).flatten)
      anchors += Set.new(html.scan(/<sup\s+class="footnote"\s+id="([^"]+)/).flatten)
      return anchors
    end

    def check_fragment_identifiers(html, anchors)
      html.scan(/<a\s+href="#([^"]+)/).flatten.each do |fragment_identifier|
        next if fragment_identifier == 'mainCol' # in layout, jumps to some DIV
        unless anchors.member?(fragment_identifier)
          guess = anchors.min { |a, b|
            Levenshtein.distance(fragment_identifier, a) <=> Levenshtein.distance(fragment_identifier, b)
          }
          puts "*** BROKEN LINK: ##{fragment_identifier}, perhaps you meant ##{guess}."
        end
      end
    end
  end
end