Class: PluginContext

Inherits:
Object
  • Object
show all
Includes:
ClassLogging, PerfStats
Defined in:
lib/httpthumbnailer/plugin.rb

Constant Summary collapse

PluginArgumentError = 
Class.new ArgumentError

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(&block) ⇒ PluginContext

Returns a new instance of PluginContext.



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# File 'lib/httpthumbnailer/plugin.rb', line 9

def initialize(&block)
	@thumbnailing_methods = []
	@edits = []
	instance_eval(&block)
end

Instance Attribute Details

#edits ⇒ Object (readonly)

Returns the value of attribute edits.



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# File 'lib/httpthumbnailer/plugin.rb', line 7

def edits
  @edits
end

#thumbnailing_methods ⇒ Object (readonly)

Returns the value of attribute thumbnailing_methods.



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# File 'lib/httpthumbnailer/plugin.rb', line 6

def thumbnailing_methods
  @thumbnailing_methods
end

Class Method Details

.from_file(file) ⇒ Object 



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# File 'lib/httpthumbnailer/plugin.rb', line 15

def self.from_file(file)
	self.new do
		instance_eval file.read, file.to_s
	end
end

Instance Method Details

#center_to_offset(center_x, center_y, w, h) ⇒ Object 



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# File 'lib/httpthumbnailer/plugin.rb', line 73

def center_to_offset(center_x, center_y, w, h)
	[center_x - w / 2, center_y - h / 2]
end

#edit(name, &block) ⇒ Object 



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# File 'lib/httpthumbnailer/plugin.rb', line 27

def edit(name, &block)
	name.kind_of? String or fail "edit name must ba a string; got: #{name.class.name}"
	block.kind_of? Proc or fail "edit '#{name}' needs to provide an implementation; got: #{name.class.name}"
	@edits << [name, block]
end

#float!(name, arg, default = nil) ⇒ Object 



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# File 'lib/httpthumbnailer/plugin.rb', line 54

def float!(name, arg, default = nil)
	value = with_default(arg, default) or raise PluginArgumentError, "expected argument '#{name}' to be a float but got no value"
	begin
		Float(value)
	rescue ArgumentError
		raise PluginArgumentError, "expected argument '#{name}' to be a float, got: #{arg}"
	end
end

#int!(name, arg, default = nil) ⇒ Object

static helpers



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# File 'lib/httpthumbnailer/plugin.rb', line 39

def int!(name, arg, default = nil)
	value = with_default(arg, default) or raise PluginArgumentError, "expected argument '#{name}' to be an integer but got no value"
	begin
		Integer(value)
	rescue ArgumentError
		raise PluginArgumentError, "expected argument '#{name}' to be an integer, got: #{arg.inspect}"
	end
end

#normalize_region(x, y, width, height) ⇒ Object 



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# File 'lib/httpthumbnailer/plugin.rb', line 77

def normalize_region(x, y, width, height)
	x = 0.0 if x < 0
	y = 0.0 if y < 0
	width = 1.0 - x if width + x > 1
	height = 1.0 - y if height + y > 1
	width = Float::EPSILON if width < 0
	height = Float::EPSILON if height < 0
	[x, y, width, height]
end

#offset_to_center(x, y, w, h) ⇒ Object 



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# File 'lib/httpthumbnailer/plugin.rb', line 69

def offset_to_center(x, y, w, h)
	[x + w / 2, y + h / 2]
end

#thumbnailing_method(name, &block) ⇒ Object 



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# File 'lib/httpthumbnailer/plugin.rb', line 21

def thumbnailing_method(name, &block)
	name.kind_of? String or fail "thumbnailing method name must ba a string; got: #{name.class.name}"
	block.kind_of? Proc or fail "thumbnailing method '#{name}' needs to provide an implementation; got: #{name.class.name}"
	@thumbnailing_methods << [name, block]
end

#ufloat!(name, arg, default = nil) ⇒ Object 



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# File 'lib/httpthumbnailer/plugin.rb', line 63

def ufloat!(name, arg, default = nil)
	ret = float!(name, arg, default)
	ret < 0 and raise PluginArgumentError, "expected argument '#{name}' to be an unsigned float, got negative value: #{arg}"
	ret
end

#uint!(name, arg, default = nil) ⇒ Object 



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# File 'lib/httpthumbnailer/plugin.rb', line 48

def uint!(name, arg, default = nil)
	ret = int!(name, arg, default)
 	ret < 0 and raise PluginArgumentError, "expected argument '#{name}' to be an unsigned integer, got negative value: #{arg}"
	ret
end

#with_default(arg, default = nil) ⇒ Object 



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# File 'lib/httpthumbnailer/plugin.rb', line 33

def with_default(arg, default = nil)
	return default if arg.nil? or arg == ''
	arg
end