| Path: | README |
| Last Update: | Sun May 28 15:19:38 E. Australia Standard Time 2006 |
I originally started designing this on weekends and after work in 2005. We started to become very interested in Rails at work and I wanted to get some experience with ruby with before we started using it full-time. I didn’t have very many ideas for anything interesting to create so, because we write a lot of multilingual webapps at my company, I decided to write a localization library. That way if my little hobby project developed into something decent, I could at least put it to good use. And here we are in 2006, my little hobby project has come a long way and become quite a useful piece of software. Not only do I use it in production sites I write at work, but I also prefer it to other existing alternatives. Therefore I have decided to make it publicly available, and I hope that other developers will find it useful too.
GLoc is a localization library. It doesn’t aim to do everything l10n-related that you can imagine, but what it does, it does very well. It was originally designed as a Rails plugin, but can also be used for plain ruby projects. Here are a list of its main features:
If you’re wondering about the name "GLoc", I’m sure you’re not alone. This project was originally just called "Localization" which was a bit too common, so when I decided to release it I decided to call it "Golly’s Localization Library" instead (Golly is my nickname), and that was long and boring so I then abbreviated that to "GLoc". What a fun story!!
This also includes a few helpers for common situations such as displaying localized date, time, "yes" or "no", etc.
At the moment, unless you manually remove the require ‘gloc-rails-text’ line from init.rb, this plugin overrides certain Rails functions to provide multilingual versions. This automatically localizes functions such as select_date(), distance_of_time_in_words() and more… The strings can be found in lang/*.yml. NOTE: This is not complete. Timezones and countries are not currently localized.
Windows users will need to first install iconv. wiki.rubyonrails.com/rails/pages/iconv
GLoc.set_config :default_language => :ja GLoc.clear_strings_except :en, :ja GLoc.set_kcode GLoc.load_localized_strings
There is more functionality provided by this plugin, that is not demonstrated above. Please read the API summary for details.
The following methods are added as both class methods and instance methods to modules/classes that include GLoc. They are also available as class methods of GLoc.
current_language # Returns the current language l(symbol, *arguments) # Returns a localized string ll(lang, symbol, *arguments) # Returns a localized string in a specific language ltry(possible_key) # Returns a localized string if passed a Symbol, else returns the same argument passed lwr(symbol, *arguments) # Uses the default rule to return a localized string. lwr_(rule, symbol, *arguments) # Uses a specified rule to return a localized string. l_has_string?(symbol) # Checks if a localized string exists set_language(language) # Sets the language for the current class or class instance set_language_if_valid(lang) # Sets the current language if the language passed is a valid language
The GLoc module also defines the following class methods:
add_localized_strings(lang, symbol_hash, override=true) # Adds a hash of localized strings backup_state(clear=false) # Creates a backup of GLoc's internal state and optionally clears everything too clear_strings(*languages) # Removes localized strings from memory clear_strings_except(*languages) # Removes localized strings from memory except for those of certain specified languages get_charset(lang) # Returns the charset used to store localized strings in memory get_config(key) # Returns a GLoc configuration value (see below) load_localized_strings(dir=nil, override=true) # Loads localized strings from all YML files in a given directory restore_state(state) # Restores a backup of GLoc's internal state set_charset(new_charset, *langs) # Sets the charset used to internally store localized strings set_config(hash) # Sets GLoc configuration values (see below) set_kcode(charset=nil) # Sets the $KCODE global variable similar_language(language) # Tries to find a valid language that is similar to the argument passed valid_languages # Returns an array of (currently) valid languages (ie. languages for which localized data exists) valid_language?(language) # Checks whether any localized strings are in memory for a given language
GLoc uses the following configuration items. They can be accessed via get_config and set_config.
:default_cookie_name :default_language :default_param_name :raise_string_not_found_errors :verbose
The GLoc module is automatically included in the following classes:
ActionController::Base ActionMailer::Base ActionView::Base ActionView::Helpers::InstanceTag ActiveRecord::Base ActiveRecord::Errors ApplicationHelper Test::Unit::TestCase
The GLoc module also defines the following controller filters:
autodetect_language_filter
GLoc also makes the following change to Rails:
Eg. validates_xxxxxx_of :name, :message => ['Your name must be at least %d characters.', MIN_LEN] Eg. validates_xxxxxx_of :name, :message => [:user_error_validation_name_too_short, MIN_LEN]
This plugin also adds the following rake tasks:
* gloc:sort - Sorts the keys in the lang ymls (also accepts a DIR argument)
The language can be set at three levels:
1. The default # GLoc.get_config :default_language 2. Class level # class A; set_language :de; end 3. Instance level # b= B.new; b.set_language :zh
Instance level has the highest priority and the default has the lowest.
Because GLoc is included at class level too, it becomes easy to associate languages with contexts. For example:
class Student
set_language :en
def say_hello
puts "We say #{l :hello} but our teachers say #{Teacher.l :hello}"
end
end
There are often situations when depending on the value of one or more variables, the surrounding text changes. The most common case of this is pluralization. Rather than hardcode these rules, they are completely definable by the user so that the user can eaasily accomodate for more complicated grammatical rules such as those found in Russian and Polish (or so I hear). To define a rule, simply include a string in the string bundle whose key begins with "gloc_rule" and then write ruby code as the value. The ruby code will be converted to a Proc when the string bundle is first read, and should return a prefix that will be appended to the string key at runtime to point to a new string. Make sense? Probably not… Please look at the following example and I am sure it will all make sense.
Simple example (string bundle / en.yml)
_gloc_rule_default: ' |n| n==1 ? "_single" : "_plural" ' man_count_plural: There are %d men. man_count_single: There is 1 man.
Simple example (code)
lwr(:man_count, 1) # => There is 1 man. lwr(:man_count, 8) # => There are 8 men.
To use rules other than the default simply call lwr_ instead of lwr, and specify the rule.
Example 2 (string bundle / en.yml)
_gloc_rule_default: ' |n| n==1 ? "_single" : "_plural" ' _gloc_rule_custom: ' |n| return "_none" if n==0; return "_heaps" if n>100; n==1 ? "_single" : "_plural" ' man_count_none: There are no men. man_count_heaps: There are heaps of men!! man_count_plural: There are %d men. man_count_single: There is 1 man.
Example 2 (code)
lwr_(:custom, :man_count, 0) # => There are no men. lwr_(:custom, :man_count, 1) # => There is 1 man. lwr_(:custom, :man_count, 8) # => There are 8 men. lwr_(:custom, :man_count, 150) # => There are heaps of men!!
GLoc includes the following helpers:
l_age(age) # Returns a localized version of an age. eg "3 years old" l_date(date) # Returns a date in a localized format l_datetime(date) # Returns a date+time in a localized format l_datetime_short(date) # Returns a date+time in a localized short format. l_lang_name(l,dl=nil) # Returns the name of a language (you must supply your own strings) l_strftime(date,fmt) # Formats a date/time in a localized format. l_time(date) # Returns a time in a localized format l_YesNo(value) # Returns localized string of "Yes" or "No" depending on the arg l_yesno(value) # Returns localized string of "yes" or "no" depending on the arg
Not all of Rails is covered but the following functions are:
distance_of_time_in_words select_day select_month select_year add_options
Simply put this in your init_engine.rb
GLoc.load_localized_strings File.join(File.dirname(__FILE__),'lang')
That way your engines strings will be loaded when the engine is started. Just simply make sure that you load your application strings after you start your engines to safely override any engine strings.
By default GLoc loads all of its default strings at startup. For example, calling set_charset ‘iso-2022-jp’ will cause this error because Russian strings are loaded by default, and the Russian strings use characters that cannot be expressed in the ISO-2022-JP charset. Before calling set_charset you should call clear_strings_except to remove strings from any languages that you will not be using. Alternatively, you can simply specify the language(s) as follows, set_charset ‘iso-2022-jp’, :ja.
Disable it as follows:
GLoc.set_config :raise_string_not_found_errors => false