Module: Dotenv::Substitutions::Variable

Defined in:
lib/dotenv/substitutions/variable.rb

Overview

Substitute variables in a value.

HOST=example.com
URL="https://$HOST"

Constant Summary collapse

VARIABLE = 
/
  (\\)?         # is it escaped with a backslash?
  (\$)          # literal $
  (?!\()        # shouldnt be followed by paranthesis
  \{?           # allow brace wrapping
  ([A-Z0-9_]+)? # optional alpha nums
  \}?           # closing brace
/xi

Class Method Summary collapse

Class Method Details

.call(value, env) ⇒ Object 



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# File 'lib/dotenv/substitutions/variable.rb', line 21

def call(value, env)
  value.gsub(VARIABLE) do |variable|
    match = $LAST_MATCH_INFO

    if match[1] == '\\'
      variable[1..-1]
    elsif match[3]
      env.fetch(match[3]) { ENV[match[3]] }
    else
      variable
    end
  end
end