Description
Hirb provides a mini view framework for console applications and uses it to improve irb’s default inspect output. Given an object or array of objects, hirb renders a view based on the object’s class and/or ancestry. Hirb offers reusable views in the form of helper classes. The two main helpers, Hirb::Helpers::Table and Hirb::Helpers::Tree, provide several options for generating ascii tables and trees. Using Hirb::Helpers::AutoTable, hirb has useful default views for at least ten popular database gems i.e. Rails’ ActiveRecord::Base. Other than views, hirb offers a smart pager and a console menu. The smart pager only pages when the output exceeds the current screen size. The menu is used in conjunction with tables to offer two dimensional menus.
Note: To read a linked version of this README, click here.
Install
Install the gem with:
sudo gem install hirb
View Tutorials
- To create and configure views, see Hirb::View or here if on the web.
- To create dynamic views, see Hirb::DynamicView or here if on the web.
Rails Example
Let’s load and enable the view framework:
$ script/console Loading local environment (Rails 2.3.5) >> require 'hirb' => true >> Hirb.enable => nil
The default configuration provides table views for ActiveRecord::Base descendants. If a class isn’t configured, Hirb reverts to irb’s default echo mode.
>> Hirb::Formatter.dynamic_config['ActiveRecord::Base']
=> {:class=>Hirb::Helpers::AutoTable, :ancestor=>true}
# Tag is a model class and descendant of ActiveRecord::Base
>> Tag.last
+-----+-------------------------+-------------+---------------+-----------+-----------+-------+
| id | created_at | description | name | namespace | predicate | value |
+-----+-------------------------+-------------+---------------+-----------+-----------+-------+
| 907 | 2009-03-06 21:10:41 UTC | | gem:tags=yaml | gem | tags | yaml |
+-----+-------------------------+-------------+---------------+-----------+-----------+-------+
1 row in set
>> Hirb::Formatter.dynamic_config['String']
=> nil
>> 'plain ol irb'
=> 'plain ol irb'
>> Hirb::Formatter.dynamic_config['Symbol']
=> nil
>> :blah
=> :blah
From above you can see there are no views configured for a String or a Symbol so Hirb defaults to irb’s echo mode. On the other hand, Tag has a view thanks to being a descendant of ActiveRecord::Base and there being an :ancestor option.
Having seen hirb display views based on an output object’s class, let’s see it handle an array of objects:
>> Tag.all :limit=>3, :order=>"id DESC" +-----+-------------------------+-------------+-------------------+-----------+-----------+----------+ | id | created_at | description | name | namespace | predicate | value | +-----+-------------------------+-------------+-------------------+-----------+-----------+----------+ | 907 | 2009-03-06 21:10:41 UTC | | gem:tags=yaml | gem | tags | yaml | | 906 | 2009-03-06 08:47:04 UTC | | gem:tags=nomonkey | gem | tags | nomonkey | | 905 | 2009-03-04 00:30:10 UTC | | article:tags=ruby | article | tags | ruby | +-----+-------------------------+-------------+-------------------+-----------+-----------+----------+ 3 rows in set
At any time you can disable Hirb if you really like irb’s lovely echo mode:
>> Hirb.disable => nil >> Tag.all :limit=>3, :order=>"id DESC" => [#<Tag id: 907, name: "gem:tags=yaml", description: nil, created_at: "2009-03-06 21:10:41", namespace: "gem", predicate: "tags", value: "yaml">, #<Tag id: 906, name: "gem:tags=nomonkey", description: nil, created_at: "2009-03-06 08:47:04", namespace: "gem", predicate: "tags", value: "nomonkey">, #<Tag id: 905, name: "article:tags=ruby", description: nil, created_at: "2009-03-04 00:30:10", namespace: "article", predicate: "tags", value: "ruby">]
Views: Anytime, Anywhere
While preconfigured tables are great for database records, sometimes you just want to create tables/views for any output object:
#These examples don't need to have Hirb::View enabled. >> Hirb.disable => nil # Imports table() and view() >> extend Hirb::Console => main # Create a table of Dates comparing them with different formats. >> table [Date.today, Date.today.next_month], :fields=>[:to_s, :ld, :ajd, :amjd, :asctime] +------------+--------+-----------+-------+--------------------------+ | to_s | ld | ajd | amjd | asctime | +------------+--------+-----------+-------+--------------------------+ | 2009-03-11 | 155742 | 4909803/2 | 54901 | Wed Mar 11 00:00:00 2009 | | 2009-04-11 | 155773 | 4909865/2 | 54932 | Sat Apr 11 00:00:00 2009 | +------------+--------+-----------+-------+--------------------------+ 2 rows in set # Same table as the previous method. However view() will be able to call any helper. >> view [Date.today, Date.today.next_month], :class=>:object_table, :fields=>[:to_s, :ld, :ajd, :amjd, :asctime]
If these console methods weren’t convenient enough, try:
# Imports view() to all objects. >> require 'hirb/import_object' =>true # Yields same table as above examples. >> [Date.today, Date.today.next_month].view :class=>:object_table, :fields=>[:to_s, :ld, :ajd, :amjd, :asctime]
Although views by default are printed to STDOUT, they can be easily modified to write anywhere:
# Setup views to write to file 'console.log'.
>> Hirb::View.render_method = lambda {|output| File.open("console.log", 'w') {|f| f.write(output) } }
# Writes to file with same table output as above example.
>> view [Date.today, Date.today.next_month], :class=>:object_table,
:fields=>[:to_s, :ld, :ajd, :amjd, :asctime]
# Doesn't write to file because Symbol doesn't have a view and thus defaults to irb's echo mode.
>> :blah
=>:blah
# Go back to printing Hirb views to STDOUT.
>> Hirb::View.reset_render_method
Pager
Hirb has both pager and formatter functionality enabled by default. If you want to turn off the functionality of either you can pass that in at startup:
Hirb.enable :pager=>false Hirb.enable :formatter=>false
or toggle their state at runtime:
Hirb::View.toggle_pager Hirb::View.toggle_formatter
Sharing Helpers and Views
If you have tested helpers you’d like to share, fork Hirb and put them under lib/hirb/helpers. To share views for certain classes, put them under lib/hirb/views. Please submit views for gems that have a nontrivial number of users.
Limitations
If using Wirble, you should call Hirb after it since they both override irb’s default output.
Motivation
Table code from gist.github.com/72234 and my console app's needs.
Credits
- Chrononaut for vertical table helper.
- crafterm, spastorino, xaviershay and joshua for bug fixes.
Bugs/Issues
Please report them on github.
Links
- tagaholic.me/2009/03/13/hirb-irb-on-the-good-stuff.html
- tagaholic.me/2009/03/18/ruby-class-trees-rails-plugin-trees-with-hirb.html
- tagaholic.me/2009/06/19/page-irb-output-and-improve-ri-with-hirb.html
Todo
- Consider generating views based on methods an object responds to.
- Provide helper methods to all views.
- Consider adding a template helper.