Module: Rubel::Core

Included in:
Runtime::Console, Runtime::Sandbox
Defined in:
lib/rubel/core.rb

Instance Method Summary collapse

Dynamic Method Handling

This class handles dynamic methods through the method_missing method

#method_missing(name, *args) ⇒ Proc, Symbol

Returns method name as a Symbol if args are empty or a Proc calling method_name with (evaluated) args [1].

Examples:

r$: MAP( [foo, bar], to_s )            
# First it converts foo, bar, to_s to symbols. Then MAP will call :to_s on [:foo, :bar]
# Thus it is equivalent to: [:foo, :bar].map(&:to_s)

r$: MAP( [0.123456, 0.98765],          # the objects
r$:      round( SUM(1,2) )     )       # instruction to round by 3. 
r$: # => Proc.new { round( 3 ) }

Returns:

  • (Proc) —

    A Proc with a method call to name and arguments args. If args are Rubel statements, they will be evaluated beforehand. This makes it possible to add objects and rubel statements to method calls.

  • (Symbol) —

    The name itself. This is useful for LOOKUPs. E.g. USER( test_123 )



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# File 'lib/rubel/core.rb', line 59

def method_missing(name, *args)
  if !(args.nil? || args.length == 0)
    ::Proc.new { self.send(name, *args)  }
  else
    name
  end
end

Instance Method Details

#execute(q = nil) ⇒ Object Also known as: query

q - The String or Proc to be executed



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# File 'lib/rubel/core.rb', line 4

def execute(q = nil)
  if q.is_a?(::String)
    q = sanitized_proc(q)
  end
  
  instance_exec(&q)
rescue => e
  ::Rubel::ErrorReporter.new(e, q)
end

#sanitize!(string) ⇒ Object

Sanitize a string from Ruby injection.

It removes “::” from the string to prevent people to access classes outside Runtime::Sandbox



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# File 'lib/rubel/core.rb', line 20

def sanitize!(string)
  string.gsub!('::', '')
end

#sanitized_proc(string) ⇒ Object

Sanitizes a string from Ruby injection and *instance_eval*s it into a lambda. This is used internally by #execute

If you execute lots of queries it is recommended to memoize the results somewhere in your application.

The sanitation removes “::” from the string to prevent people to access classes outside Runtime::Sandbox. This has no effect in other runtimes.



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# File 'lib/rubel/core.rb', line 33

def sanitized_proc(string)
  sanitize!(string)
  instance_eval("lambda { #{string} }")
end