Class: Dragonfly::Content

Inherits:
Object show all
Extended by:
Forwardable
Includes:
HasFilename
Defined in:
lib/dragonfly/content.rb

Overview

A Dragonfly::Content object is responsible for holding

  1. content (in the form of a data string, file, tempfile, or path)

  2. metadata about the content (i.e. name, etc.)

Furthermore, it belongs to a Dragonfly app, so has access to its already registered generators, processors, analysers and datastore. It provides convenience methods for updating its content, and though the original data may have been in the form of a String, or a Pathname, etc. methods like “path”, “data” and “file” will always work regardless.

It is acted upon in generator, processor, analyser and datastore methods and provides a standard interface for updating content, no matter how that content first got there (whether in the form of a String/Pathname/File/etc.)

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from HasFilename

#basename, #basename=, #ext, #ext=

Constructor Details

#initialize(app, obj = "", meta = nil) ⇒ Content

Returns a new instance of Content.



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# File 'lib/dragonfly/content.rb', line 23

def initialize(app, obj="", meta=nil)
  @app = app
  @meta = {}
  @previous_temp_objects = []
  update(obj, meta)
end

Instance Attribute Details

#app ⇒ Object (readonly)

Returns the value of attribute app.



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# File 'lib/dragonfly/content.rb', line 35

def app
  @app
end

#meta ⇒ Hash

Returns:



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# File 'lib/dragonfly/content.rb', line 42

def meta
  @meta
end

#temp_object ⇒ Object

Returns the value of attribute temp_object.



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# File 'lib/dragonfly/content.rb', line 39

def temp_object
  @temp_object
end

Instance Method Details

#add_meta(meta) ⇒ Object

Add to the meta (merge)

Parameters:

  • meta (Hash) —

    • should be json-like, i.e. contain no types other than String, Number, Boolean



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# File 'lib/dragonfly/content.rb', line 126

def add_meta(meta)
  self.meta.merge!(meta)
  self
end

#analyse(name) ⇒ Object

Analyse the content using a pre-registered analyser

Examples:

content.analyse(:width)  # ===> 280


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# File 'lib/dragonfly/content.rb', line 106

def analyse(name)
  analyser_cache[name.to_s] ||= app.get_analyser(name).call(self)
end

#b64_data ⇒ String

Returns A data url representation of the data.

Examples:

"data:image/jpeg;base64,IGSsdhfsoi..."

Returns:

  • (String) —

    A data url representation of the data



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# File 'lib/dragonfly/content.rb', line 186

def b64_data
  "data:#{mime_type};base64,#{Base64.encode64(data)}"
end

#close ⇒ Object 



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# File 'lib/dragonfly/content.rb', line 190

def close
  previous_temp_objects.each{|temp_object| temp_object.close }
  temp_object.close
end

#data ⇒ String

Returns the content data as a string (even if it was initialized with a file).

Returns:

  • (String) —

    the content data as a string (even if it was initialized with a file)



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# File 'lib/dragonfly/content.rb', line 63

def_delegators :temp_object,
:data, :file, :tempfile, :path, :size, :each, :to_file, :to_tempfile

#file ⇒ File

Returns the content as a readable file (even if it was initialized with data).

Examples:

content.file

With a block (it closes the file at the end)

content.file do |f|
  # do something with f
end

Returns:

  • (File) —

    the content as a readable file (even if it was initialized with data)



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# File 'lib/dragonfly/content.rb', line 63

def_delegators :temp_object,
:data, :file, :tempfile, :path, :size, :each, :to_file, :to_tempfile

#generate!(name, *args) ⇒ Content

Set the content using a pre-registered generator

Examples:

content.generate!(:text, "some text")

Returns:



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# File 'lib/dragonfly/content.rb', line 89

def generate!(name, *args)
  app.get_generator(name).call(self, *args)
  self
end

#initialize_copy(other) ⇒ Object

Used by ‘dup’ and ‘clone’



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# File 'lib/dragonfly/content.rb', line 31

def initialize_copy(other)
  self.meta = meta.dup
end

#inspect ⇒ Object 



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# File 'lib/dragonfly/content.rb', line 195

def inspect
  "<#{self.class.name} temp_object=#{temp_object.inspect}>"
end

#mime_type ⇒ String

The mime-type taken from the name’s file extension

Examples:

“image/jpeg”

Returns:

  • (String) 


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# File 'lib/dragonfly/content.rb', line 81

def mime_type
  meta['mime_type'] || app.mime_type_for(ext)
end

#name ⇒ String

Examples:

“beach.jpg”

Returns:

  • (String) 


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# File 'lib/dragonfly/content.rb', line 68

def name
  meta["name"]
end

#name=(name) ⇒ Object

Examples:

content.name = "beach.jpg"


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# File 'lib/dragonfly/content.rb', line 74

def name=(name)
  meta["name"] = name
end

#path ⇒ String

Returns a file path for the content (even if it was initialized with data).

Returns:

  • (String) —

    a file path for the content (even if it was initialized with data)



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# File 'lib/dragonfly/content.rb', line 63

def_delegators :temp_object,
:data, :file, :tempfile, :path, :size, :each, :to_file, :to_tempfile

#process!(name, *args) ⇒ Content

Update the content using a pre-registered processor

Examples:

content.process!(:convert, "-resize 300x300")

Returns:



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# File 'lib/dragonfly/content.rb', line 98

def process!(name, *args)
  app.get_processor(name).call(self, *args)
  self
end

#shell_eval(opts = {}) ⇒ Object

Analyse the content using a shell command

Examples:

content.shell_eval do |path|
  "file --mime-type #{path}"
end
# ===> "beach.jpg: image/jpeg"

Parameters:

  • opts (Hash) (defaults to: {}) —

    passing :escape => false doesn’t shell-escape each word



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# File 'lib/dragonfly/content.rb', line 138

def shell_eval(opts={})
  should_escape = opts[:escape] != false
  command = yield(should_escape ? shell.escape(path) : path)
  run command, :escape => should_escape
end

#shell_generate(opts = {}) ⇒ Content

Set the content using a shell command

Examples:

content.shell_generate do |path|
  "/usr/local/bin/generate_text gumfry -o #{path}"
end

Parameters:

  • opts (Hash) (defaults to: {}) —

    :ext sets the file extension of the new path and :escape => false doesn’t shell-escape each word

Returns:



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# File 'lib/dragonfly/content.rb', line 151

def shell_generate(opts={})
  ext = opts[:ext] || self.ext
  should_escape = opts[:escape] != false
  tempfile = Utils.new_tempfile(ext)
  new_path = should_escape ? shell.escape(tempfile.path) : tempfile.path
  command = yield(new_path)
  run(command, :escape => should_escape)
  update(tempfile)
end

#shell_update(opts = {}) ⇒ Content

Update the content using a shell command

Examples:

content.shell_update do |old_path, new_path|
  "convert -resize 20x10 #{old_path} #{new_path}"
end

Parameters:

  • opts (Hash) (defaults to: {}) —

    :ext sets the file extension of the new path and :escape => false doesn’t shell-escape each word

Returns:



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# File 'lib/dragonfly/content.rb', line 168

def shell_update(opts={})
  ext = opts[:ext] || self.ext
  should_escape = opts[:escape] != false
  tempfile = Utils.new_tempfile(ext)
  old_path = should_escape ? shell.escape(path) : path
  new_path = should_escape ? shell.escape(tempfile.path) : tempfile.path
  command = yield(old_path, new_path)
  run(command, :escape => should_escape)
  update(tempfile)
end

#size ⇒ Fixnum

Returns the size in bytes.

Returns:

  • (Fixnum) —

    the size in bytes



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# File 'lib/dragonfly/content.rb', line 63

def_delegators :temp_object,
:data, :file, :tempfile, :path, :size, :each, :to_file, :to_tempfile

#store(opts = {}) ⇒ Object 



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# File 'lib/dragonfly/content.rb', line 179

def store(opts={})
  datastore.write(self, opts)
end

#to_file ⇒ File

Returns a new file.

Parameters:

  • path (String)

Returns:

  • (File) —

    a new file



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# File 'lib/dragonfly/content.rb', line 63

def_delegators :temp_object,
:data, :file, :tempfile, :path, :size, :each, :to_file, :to_tempfile

#to_tempfile ⇒ Tempfile

Returns a new tempfile.

Returns:

  • (Tempfile) —

    a new tempfile



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# File 'lib/dragonfly/content.rb', line 63

def_delegators :temp_object,
:data, :file, :tempfile, :path, :size, :each, :to_file, :to_tempfile

#update(obj, meta = nil) ⇒ Content

Update the content

Parameters:

  • obj (String, Pathname, Tempfile, File, Content, TempObject) —

    can be any of these types

  • meta (Hash) (defaults to: nil) —

    • should be json-like, i.e. contain no types other than String, Number, Boolean

Returns:



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# File 'lib/dragonfly/content.rb', line 114

def update(obj, meta=nil)
  meta ||= {}
  self.temp_object = TempObject.new(obj, meta['name'])
  self.meta['name'] ||= temp_object.name if temp_object.name
  clear_analyser_cache
  add_meta(obj.meta) if obj.respond_to?(:meta)
  add_meta(meta)
  self
end