Module: TinyDot

Defined in:
lib/tiny_dot.rb

Overview

The TinyDot module provides methods for converting data from different formats (environment variables, YAML, JSON and Hashes) into a nested Struct. This allows for easy access to the data using dot notation.

The from_env method converts the current environment variables into a Struct.

The from_yaml method takes a string containing YAML data and converts it into a Struct.

The from_json method takes a string containing JSON data and converts it into a Struct.

The from_csv method takes a string containing raw CSV data and converts it to an Array of Struct.

The from_hash method takes a Hash and converts it into a Struct. It really just calls the _hash_to_struct method.

The _hash_to_struct is a private method that is used by the other methods to convert the data from a hash into a Struct. It handles nested data by recursively calling itself when it encounters a Hash or an array within the data.

The _to_attr_friendly_symbols is a private method that is used to convert keys in the hash to symbols that can be used as attributes in a Struct. It replaces spaces and dashes with underscores and converts the keys to symbols.

Please note that the JSON and YAML are required to be passed as String.

Because this module constructs a series of nested Structs from Hash-like inputs, it means you can read/write data pretty easily:

 > s = TinyDot.from_json(<some deeply nested JSON>)
=> <struct ... >
 > s.foo.bar.baz
=> 5
 > s.foo.bar.baz = 99
 < s.foo.bar.baz
=> 99

Class Method Summary collapse

Class Method Details

._hash_to_struct(obj) ⇒ Object 



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# File 'lib/tiny_dot.rb', line 69

def _hash_to_struct(obj)
  case obj
  when Hash
    return obj if obj.keys.empty?

    struct = ::Struct.new(*_to_attr_friendly_symbols(obj.keys))
    struct.new(*obj.values.map { |v| _hash_to_struct(v) })
  when Array
    obj.map { |v| _hash_to_struct(v) }
  else
    obj
  end
end

._to_attr_friendly_symbols(keys) ⇒ Object 



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# File 'lib/tiny_dot.rb', line 83

def _to_attr_friendly_symbols(keys)
  keys
    .map{|k| k.to_s.gsub(/[-\s]/, '_') }
    .map(&:to_sym)
end

.from_csv(csv_string) ⇒ Object 



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# File 'lib/tiny_dot.rb', line 60

def from_csv(csv_string)
  data = CSV.parse(csv_string, headers: true)
  data.map { |row| _hash_to_struct(row.to_hash) }
end

.from_env ⇒ Object 



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# File 'lib/tiny_dot.rb', line 46

def from_env
  _hash_to_struct(ENV.to_h)
end

.from_hash(hash) ⇒ Object 



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# File 'lib/tiny_dot.rb', line 65

def from_hash(hash)
  _hash_to_struct(hash)
end

.from_json(json_string) ⇒ Object 



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# File 'lib/tiny_dot.rb', line 55

def from_json(json_string)
  json = Oj.load(json_string)
  _hash_to_struct(json)
end

.from_yaml(yaml_string) ⇒ Object 



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# File 'lib/tiny_dot.rb', line 50

def from_yaml(yaml_string)
  yaml = Psych.load(yaml_string)
  _hash_to_struct(yaml)
end