Class: LittleGhost::Sandbox::Limits

Inherits:
Object
  • Object
show all
Defined in:
lib/little_ghost/sandbox/limits.rb

Overview

Bounded file and process output sizes applied by Sandbox tools.

Constant Summary collapse

DEFAULTS = 
{
  read_bytes: 1_000_000,
  write_bytes: 1_000_000,
  list_entries: 10_000,
  output_bytes: 1_000_000
}.freeze

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(**values) ⇒ Limits

Builds positive file and process output limits.

Raises:



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# File 'lib/little_ghost/sandbox/limits.rb', line 23

def initialize(**values)
  unknown = values.keys - DEFAULTS.keys
  raise PolicyError, "unknown sandbox limits: #{unknown.join(", ")}" unless unknown.empty?

  DEFAULTS.merge(values).each do |name, value|
    value = Integer(value)
    raise PolicyError, "sandbox #{name} must be positive" unless value.positive?

    instance_variable_set("@#{name}", value)
  rescue ArgumentError, TypeError
    raise PolicyError, "sandbox #{name} must be an integer"
  end
  freeze
end

Instance Attribute Details

#list_entries ⇒ Object (readonly)

Maximum entries returned by one directory listing.



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# File 'lib/little_ghost/sandbox/limits.rb', line 43

def list_entries
  @list_entries
end

#output_bytes ⇒ Object (readonly)

Maximum bytes captured from each child output stream.



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# File 'lib/little_ghost/sandbox/limits.rb', line 45

def output_bytes
  @output_bytes
end

#read_bytes ⇒ Object (readonly)

Maximum bytes returned by one filesystem read.



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# File 'lib/little_ghost/sandbox/limits.rb', line 39

def read_bytes
  @read_bytes
end

#write_bytes ⇒ Object (readonly)

Maximum bytes accepted by one filesystem write.



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# File 'lib/little_ghost/sandbox/limits.rb', line 41

def write_bytes
  @write_bytes
end

Class Method Details

.coerce(value) ⇒ Object

Returns value unchanged or builds limits from a Hash.

Raises:



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# File 'lib/little_ghost/sandbox/limits.rb', line 15

def self.coerce(value)
  return value if value.is_a?(self)
  raise PolicyError, "sandbox limits must be a Hash" unless value.respond_to?(:to_h)

  new(**value.to_h.transform_keys(&:to_sym))
end