如何递归地将YAML文件展平为JSON对象,其中键是以点分隔的字符串？

Question

例如,如果我有YAML文件

en:
  questions:
    new: 'New Question'
    other:
      recent: 'Recent'
      old: 'Old'

这最终会像json对象一样

{
  'questions.new': 'New Question',
  'questions.other.recent': 'Recent',
  'questions.other.old': 'Old'
}

Answer 1

require 'yaml'

yml = %Q{
en:
  questions:
    new: 'New Question'
    other:
      recent: 'Recent'
      old: 'Old'
}

yml = YAML.load(yml)
translations = {}

def process_hash(translations, current_key, hash)
  hash.each do |new_key, value|
    combined_key = [current_key, new_key].delete_if { |k| k.blank? }.join('.')
    if value.is_a?(Hash)
      process_hash(translations, combined_key, value)
    else
      translations[combined_key] = value
    end
  end
end

process_hash(translations, '', yml['en'])
p translations

Answer 2

@ Ryan的递归答案是要走的路,我只是做了一点Rubyish:

yml = YAML.load(yml)['en']

def flatten_hash(my_hash, parent=[])
  my_hash.flat_map do |key, value|
    case value
      when Hash then flatten_hash( value, parent+[key] )
      else [(parent+[key]).join('.'), value]
    end
  end
end

p flatten_hash(yml) #=> ["questions.new", "New Question", "questions.other.recent", "Recent", "questions.other.old", "Old"]
p Hash[*flatten_hash(yml)] #=> {"questions.new"=>"New Question", "questions.other.recent"=>"Recent", "questions.other.old"=>"Old"}

然后要将它变成json格式,你只需要'json'并在hash上调用to_json方法.

Answer 3

由于问题是关于在Rails应用程序上为i18n使用YAML文件，因此值得注意的是i18ngem提供了一个帮助程序模块I18n::Backend::Flatten，该模块完全像这样平整翻译：

test.rb：

require 'yaml'
require 'json'
require 'i18n'

yaml = YAML.load <<YML
en:
  questions:
    new: 'New Question'
    other:
      recent: 'Recent'
      old: 'Old'
YML
include I18n::Backend::Flatten
puts JSON.pretty_generate flatten_translations(nil, yaml, nil, false)

输出：

$ ruby test.rb
{
  "en.questions.new": "New Question",
  "en.questions.other.recent": "Recent",
  "en.questions.other.old": "Old"
}