Class: Dip::Environment

Inherits:
Object
  • Object
show all
Defined in:
lib/dip/environment.rb

Constant Summary collapse

VAR_REGEX = 
/\$\{?(?<var_name>[a-zA-Z_][a-zA-Z0-9_]*)\}?/.freeze
SPECIAL_VARS = 
%i[os work_dir_rel_path].freeze

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(default_vars) ⇒ Environment

Returns a new instance of Environment.



12
13
14
15
16
 
# File 'lib/dip/environment.rb', line 12

def initialize(default_vars)
  @vars = {}

  merge(default_vars || {})
end

Instance Attribute Details

#vars ⇒ Object (readonly)

Returns the value of attribute vars.



10
11
12
 
# File 'lib/dip/environment.rb', line 10

def vars
  @vars
end

Instance Method Details

#[](name) ⇒ Object 



25
26
27
 
# File 'lib/dip/environment.rb', line 25

def [](name)
  vars.fetch(name) { ENV[name] }
end

#[]=(key, value) ⇒ Object 



33
34
35
 
# File 'lib/dip/environment.rb', line 33

def []=(key, value)
  @vars[key] = value
end

#fetch(name, &block) ⇒ Object 



29
30
31
 
# File 'lib/dip/environment.rb', line 29

def fetch(name, &block)
  vars.fetch(name) { ENV.fetch(name, &block) }
end

#interpolate(value) ⇒ Object Also known as: replace 



37
38
39
40
41
42
43
44
45
46
47
 
# File 'lib/dip/environment.rb', line 37

def interpolate(value)
  value.gsub(VAR_REGEX) do |match|
    var_name = Regexp.last_match[:var_name]

    if special_vars.key?(var_name)
      fetch(var_name) { send(special_vars[var_name]) }
    else
      fetch(var_name) { match }
    end
  end
end

#merge(new_vars) ⇒ Object 



18
19
20
21
22
23
 
# File 'lib/dip/environment.rb', line 18

def merge(new_vars)
  new_vars.each do |key, value|
    key = key.to_s
    @vars[key] = ENV.fetch(key) { interpolate(value.to_s) }
  end
end