lib/fluent/plugin/out_simple_arithmetic.rb in fluent-plugin-simplearithmetic-0.0.1.pre vs lib/fluent/plugin/out_simple_arithmetic.rb in fluent-plugin-simplearithmetic-0.0.1

@@ -9,10 +9,13 @@
     config_param :undefined_variables, :string, :default => 'undefined'
 
     # 'nil', 'undefined', 'error_string'
     config_param :how_to_process_error, :string, :default => 'error_string'
 
+    config_param :replace_hyphen, :string, :default => '__HYPHON__'
+    config_param :replace_dollar, :string, :default => '__DOLLAR__'
+
     attr_accessor :_formulas
 
     def initialize
       super
       require 'time'
@@ -39,14 +42,13 @@
         end
       }
 
       # Create functions
       @_formulas = []
-
       def create_func(var, expr)
         begin
-          f_argv = expr.scan(/[a-zA-Z][\w\d\.]*/).uniq.select{|x| not x.start_with?('Time.iso8601')}
+          f_argv = expr.scan(/[a-zA-Z\_][\w\d\.\_]*/).uniq.select{|x| not x.start_with?('Time.iso8601')}
           f = eval('lambda {|' + f_argv.join(',') + '| ' + expr + '}')
           return [f, f_argv]
         rescue SyntaxError
           raise Fluent::ConfigError, "SyntaxError at formula `#{var}`: #{expr}"
         end
@@ -59,10 +61,14 @@
           element.has_key?(var)   # to suppress unread configuration warning
           formula, f_argv = create_func(var, expr)
           @_formulas.push [var, f_argv, formula]
         }
       }
+      if @_formulas.empty?
+        raise Fluent::ConfigError, "No formulas found"
+      end
+
     end
 
     def has_all_keys?(record, argv)
       argv.each {|var|
         if not record.has_key?(var)
@@ -78,11 +84,34 @@
         argv.push(record[v])
       }
       return formula.call(*argv)
     end
 
+    # functions for symbols
+    def replace_symbols(record)
+      # 'var-1' -> 'var__HYPHEN__1'
+      new_record = {}
+      record.each_pair {|key, value|
+        new_key = key.gsub('-', @replace_hyphen).gsub('$', @replace_dollar)
+        new_record[new_key] = value
+      }
+      return new_record
+    end
+
+    def restore_symbols(record)
+      # 'var__HYPHEN__1' -> 'var-1'
+      new_record = {}
+      record.each_pair {|key, value|
+        new_key = key.gsub(@replace_hyphen, '-').gsub(@replace_dollar, '$')
+        new_record[new_key] = value
+      }
+      new_record
+    end
+
     def calculate(record)
+      record = replace_symbols(record)
+
       @_formulas.each {|var, f_argv, formula|
         if not has_all_keys?(record, f_argv)
           if @undefined_variables == 'nil'
             record[var] = nil
           end
@@ -98,10 +127,11 @@
           when 'nil'
             record[var] = nil
           end
         end
       }
-      record
+
+      restore_symbols(record)
     end
 
     def emit(tag, es, chain)
       chain.next
       es.each { |time, record|