Class: ImageVise

Inherits:
Object
  • Object
show all
Defined in:
lib/image_vise.rb

Defined Under Namespace

Classes: AutoOrient, Crop, EllipseStencil, FileResponse, FitCrop, Geom, ImageRequest, Pipeline, RenderEngine, SRGB, Sharpen, StripMetadata

Constant Summary collapse

VERSION = 
'0.0.21'

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.add_allowed_host!(hostname) ⇒ Object

Add an allowed host



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# File 'lib/image_vise.rb', line 27

def add_allowed_host!(hostname)
  S_MUTEX.synchronize { @allowed_hosts << hostname }
end

.add_operator(operator_name, object_responding_to_new) ⇒ Object

Adds an operator



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# File 'lib/image_vise.rb', line 87

def add_operator(operator_name, object_responding_to_new)
  @operators[operator_name.to_s] = object_responding_to_new
end

.add_secret_key!(key) ⇒ Object

Adds a key against which the parameters are going to be verified. Multiple applications may have their own different keys, so we need to have multiple keys.



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# File 'lib/image_vise.rb', line 56

def add_secret_key!(key)
  S_MUTEX.synchronize { @keys << key }
  self
end

.allow_filesystem_source!(glob_pattern) ⇒ Object 



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# File 'lib/image_vise.rb', line 41

def allow_filesystem_source!(glob_pattern)
  S_MUTEX.synchronize { @allowed_glob_patterns << glob_pattern }
end

.allowed_filesystem_sources ⇒ Object 



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# File 'lib/image_vise.rb', line 45

def allowed_filesystem_sources
  S_MUTEX.synchronize { @allowed_glob_patterns.to_a }
end

.allowed_hosts ⇒ Object

Returns both the allowed hosts added at runtime and the ones set in the constant



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# File 'lib/image_vise.rb', line 32

def allowed_hosts
  S_MUTEX.synchronize { @allowed_hosts.to_a }
end

.call(rack_env) ⇒ Object

Made available since the object that is used with ‘mount()` in Rails has to, by itself, to respond to `call`.

Thanks to this method you can do this:

mount ImageVise => '/thumbnails'

instead of having to do

mount ImageVise.new => '/thumbnails'



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# File 'lib/image_vise.rb', line 116

def self.call(rack_env)
  ImageVise::RenderEngine.new.call(rack_env)
end

.defined_operator_names ⇒ Object 



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# File 'lib/image_vise.rb', line 96

def defined_operator_names
  @operators.keys
end

.deny_filesystem_sources! ⇒ Object 



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# File 'lib/image_vise.rb', line 49

def deny_filesystem_sources!
  S_MUTEX.synchronize { @allowed_glob_patterns.clear }
end

.destroy(maybe_image) ⇒ Object

Used as a shorthand to force-destroy Magick images in ensure() blocks. Since ensure blocks sometimes deal with variables in inconsistent states (variable in scope but not yet set to an image) we take the possibility of nils into account. We also deal with Magick::Image objects that already have been destroyed in a clean manner.



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# File 'lib/image_vise.rb', line 128

def self.destroy(maybe_image)
  return unless maybe_image
  return unless maybe_image.respond_to?(:destroy!)
  return if maybe_image.destroyed?
  maybe_image.destroy!
end

.image_params(src_url:, secret:) {|p| ... } ⇒ Hash

Generate a set of querystring params for a resized image. Yields a Pipeline object that will receive method calls for adding image operations to a stack.

ImageVise.image_params(src_url: image_url_on_s3, secret: '...') do |p|
   p.center_fit width: 128, height: 128 
   p.elliptic_stencil
end #=> {q: '...', sig: '...'}

The query string elements can be then passed on to RenderEngine for validation and execution.

Yields:

  • (p)

Returns:

  • (Hash)

Raises:

  • (ArgumentError) 


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# File 'lib/image_vise.rb', line 79

def image_params(src_url:, secret:)
  p = Pipeline.new
  yield(p)
  raise ArgumentError, "Image pipeline has no steps defined" if p.empty?
  ImageRequest.new(src_url: src_url, pipeline: p).to_query_string_params(secret)
end

.operator_from(operator_name) ⇒ Object

Gets an operator by name



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# File 'lib/image_vise.rb', line 92

def operator_from(operator_name)
  @operators.fetch(operator_name.to_s)
end

.operator_name_for(operator) ⇒ Object 



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# File 'lib/image_vise.rb', line 100

def operator_name_for(operator)
  @operators.key(operator.class) or raise "Operator #{operator.inspect} not registered using ImageVise.add_operator"
end

.reset_allowed_hosts! ⇒ Object

Resets all allowed hosts



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# File 'lib/image_vise.rb', line 22

def reset_allowed_hosts!
  S_MUTEX.synchronize { @allowed_hosts.clear }
end

.reset_secret_keys! ⇒ Object

Removes all set keys



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# File 'lib/image_vise.rb', line 37

def reset_secret_keys!
  S_MUTEX.synchronize { @keys.clear }
end

.secret_keys ⇒ Object

Returns the array of defined keys or raises an exception if no keys have been set yet



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# File 'lib/image_vise.rb', line 62

def secret_keys
  keys = S_MUTEX.synchronize { @keys.any? && @keys.to_a }
  keys or raise "No keys set, add a key using `ImageVise.add_secret_key!(key)'"
end

Instance Method Details

#call(rack_env) ⇒ Object 



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# File 'lib/image_vise.rb', line 120

def call(rack_env)
  ImageVise::RenderEngine.new.call(rack_env)
end