Improve 'docs:download' command

- Add --default option
- Add --installed option
- De-document --all option. With multi-version support just added, the
  complete set of documentations is quickly going to grow beyond its
  current size of 500MB and 30,000 documents.

Ref #25.

README.md

@@ -27,15 +27,15 @@ DevDocs requires Ruby 2.3.0, libcurl, and a JavaScript runtime supported by [Exe
 git clone https://github.com/Thibaut/devdocs.git && cd devdocs
 gem install bundler
 bundle install
-thor docs:download --all
+thor docs:download --default
 rackup
 ```
 
 Finally, point your browser at [localhost:9292](http://localhost:9292) (the first request will take a few seconds to compile the assets). You're all set.
 
-The `thor docs:download` command is used to download/update individual documentations (e.g. `thor docs:download html css`), or all at the same time (using the `--all` option). You can see the list of available documentations by running `thor docs:list`.
+The `thor docs:download` command is used to download pre-generated documentations from DevDocs's servers (e.g. `thor docs:download html css`). You can see the list of available documentations and versions by running `thor docs:list`. To update all downloaded documentations, run `thor docs:download --installed`.
 
-**Note:** there is currently no update mechanism other than `git pull origin master` to update the code and `thor docs:download` to download the latest version of the docs. To stay informed about new releases, be sure to [watch](https://github.com/Thibaut/devdocs/subscription) this repository and/or subscribe to the [newsletter](http://eepurl.com/HnLUz).
+**Note:** there is currently no update mechanism other than `git pull origin master` to update the code and `thor docs:download --installed` to download the latest version of the docs. To stay informed about new releases, be sure to [watch](https://github.com/Thibaut/devdocs/subscription) this repository.
 
 Alternatively, DevDocs may be started as a Docker container:
 

assets/javascripts/templates/pages/root_tmpl.coffee.erb

@@ -10,8 +10,9 @@ app.templates.intro = """
       <li>Your local version of DevDocs won't self-update. Unless you're modifying the code,
           I&nbsp;recommend using the hosted version at <a href="http://devdocs.io">devdocs.io</a>.
       <li>Run <code>thor docs:list</code> to see all available documentations.
-      <li>Run <code>thor docs:download --all</code> to download/update all documentations.
-        <li>To be notified about new versions, don't forget to <a href="https://github.com/Thibaut/devdocs/subscription">watch the repository</a> on GitHub.
+      <li>Run <code>thor docs:download &lt;name&gt;</code> to download documentations.
+      <li>Run <code>thor docs:download --installed</code> to update all downloaded documentations.
+      <li>To be notified about new versions, don't forget to <a href="https://github.com/Thibaut/devdocs/subscription">watch the repository</a> on GitHub.
       <li>The <a href="https://github.com/Thibaut/devdocs/issues">issue tracker</a> is the preferred channel for bug reports and
           feature requests. For everything else, use the <a href="https://groups.google.com/d/forum/devdocs">mailing list</a>.
       <li>Contributions are welcome. See the <a href="https://github.com/Thibaut/devdocs/blob/master/CONTRIBUTING.md">guidelines</a>.

lib/docs.rb

@@ -39,7 +39,19 @@ module Docs
     all.flat_map(&:versions)
   end
 
-  def self.find(name, version)
+  def self.defaults
+    %w(css dom dom_events html http javascript).map(&method(:find))
+  end
+
+  def self.installed
+    Dir["#{store_path}/**/index.json"].
+      map { |file| file[%r{/([^/]*)/index\.json\z}, 1] }.
+      sort!.
+      map { |path| all_versions.find { |doc| doc.path == path } }.
+      compact
+  end
+
+  def self.find(name, version = nil)
     const = name.camelize
     doc = const_get(const)
 

lib/tasks/docs.thor

@@ -94,11 +94,21 @@ class DocsCLI < Thor
     puts 'Done'
   end
 
-  desc 'download (<doc> <doc@version>... | --all)', 'Download documentations'
+  desc 'download (<doc> <doc@version>... | --default | --installed)', 'Download documentations'
+  option :default, type: :boolean
+  option :installed, type: :boolean
   option :all, type: :boolean
   def download(*names)
     require 'unix_utils'
-    docs = options[:all] ? Docs.all : find_docs(names)
+    docs = if options[:default]
+      Docs.defaults
+    elsif options[:installed]
+      Docs.installed
+    elsif options[:all]
+      Docs.all_versions
+    else
+      find_docs(names)
+    end
     assert_docs(docs)
     download_docs(docs)
     generate_manifest
@@ -136,7 +146,7 @@ class DocsCLI < Thor
   def assert_docs(docs)
     if docs.empty?
       puts 'ERROR: called with no arguments.'
-      puts 'Run "thor docs:list" for usage patterns.'
+      puts 'Run "thor list" for usage patterns.'
       exit
     end
   end
@@ -154,6 +164,7 @@ class DocsCLI < Thor
 
     require 'thread'
     length = docs.length
+    mutex = Mutex.new
     i = 0
 
     (1..4).map do
@@ -165,7 +176,7 @@ class DocsCLI < Thor
           rescue => e
             "FAILED (#{e.class}: #{e.message})"
           end
-          puts "(#{i += 1}/#{length}) #{doc.name} #{status}"
+          mutex.synchronize { puts "(#{i += 1}/#{length}) #{doc.name}#{ " #{doc.version}" if doc.version} #{status}" }
         end
       end
     end.map(&:join)