Class: Amp::Support::Template

Inherits:
Object
  • Object
show all
Defined in:
lib/amp/templates/template.rb

Overview

Template

Class representing a template in the amp system

Author:

  • Michael Edgar

Direct Known Subclasses

FileTemplate

Class Attribute Summary collapse

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(name, renderer = :erb, text = "") ⇒ Template

Creates a new template with the given values. The name is how you will reference the template using the –template option from the command line, so choose it wisely!

Parameters:

  • name (String, Symbol, #to_s) —

    the name of the template, which is invoked using –template

  • type (Symbol) —

    the type of the template. Indicates the renderer used.

  • text (String) (defaults to: "") —

    the text of the template, which presumably has some templating code to substitute in local variables and make a nice output system.



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# File 'lib/amp/templates/template.rb', line 86

def initialize(name, renderer = :erb, text = "")
  @name, @renderer, @text = name, renderer, text
  Template.register(name, self)
end

Class Attribute Details

.all_templates ⇒ Object

Returns the value of attribute all_templates.



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# File 'lib/amp/templates/template.rb', line 12

def all_templates
  @all_templates
end

Instance Attribute Details

#name ⇒ Object

Returns the value of attribute name.



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# File 'lib/amp/templates/template.rb', line 75

def name
  @name
end

#renderer ⇒ Object

Returns the value of attribute renderer.



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# File 'lib/amp/templates/template.rb', line 75

def renderer
  @renderer
end

#text ⇒ Object

Returns the value of attribute text.



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# File 'lib/amp/templates/template.rb', line 75

def text
  @text
end

Class Method Details

.[](template) ⇒ Template

Returns the template with the given name.

Parameters:

  • template (String, Symbol, #to_sym) —

    the name of the template to retrieve

Returns:

  • (Template) —

    the template with the given name



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# File 'lib/amp/templates/template.rb', line 19

def [](template)
  ensure_templates_loaded
  return all_templates[template.to_sym]
end

.ensure_templates_loaded ⇒ Object

Makes sure the default templates have been loaded.

About the use of instance_eval - this method could potentially be run more than once. There is no reason for it to ever run more than once. So we’ll redefine it to do nothing.



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# File 'lib/amp/templates/template.rb', line 67

def ensure_templates_loaded
  load_default_templates
  instance_eval do
    def ensure_templates_loaded; end
  end
end

.load_default_templates ⇒ Object

Registers the default templates. Separated into a method (instead of automatically run) because templates aren’t used enough to justify the IO hit from loading them in.



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# File 'lib/amp/templates/template.rb', line 55

def load_default_templates
  Dir[File.expand_path(File.join(File.dirname(__FILE__), "*.erb"))].each do |f|
    name = f.split('/').last.chomp('.erb').sub('.','-')
    FileTemplate.new(name, f)
  end
end

.register(name, template) ⇒ Object

Registers a template with the Amp system. Should have a unique name.

Parameters:

  • name (String, Symbol, #to_sym) —

    the name of the template. Should be unique.

  • template (Template) —

    the template to register.



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# File 'lib/amp/templates/template.rb', line 29

def register(name, template)
  all_templates[name.to_sym] = template
end

.templates_loaded? ⇒ Boolean

Returns whether any templates have been loaded. Used for lazy loading of templates.

Returns:

  • (Boolean) —

    have the default templates, or any templates, been loaded?



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# File 'lib/amp/templates/template.rb', line 48

def templates_loaded?
  all_templates.any?
end

.unregister(name) ⇒ Object

Unregisters a template with the Amp system. If the name is not found, an exception is thrown.

Parameters:

  • name (String, Symbol, #to_sym) —

    the name of the template to remove from the system.

Raises:

  • (ArgumentError) 


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# File 'lib/amp/templates/template.rb', line 39

def unregister(name)
  raise ArgumentError.new("Unknown template: #{name}") unless all_templates[name.to_sym]
  all_templates.delete name.to_sym
end

Instance Method Details

#render(locals = {}, render_binding = binding) ⇒ String

TODO:

make locals work for ERb without bootleg hax

Renders the template with the given local variables. Uses whichever templating engine you set. Note: if you use HAML, you’ll need to have HAML installed. This is why none of the default templates use HAML.

Parameters:

  • locals (Hash) (defaults to: {}) —

    the local variables passed to the template. Works for HAML so far, not for erb.

Returns:

  • (String) —

    the parsed template



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# File 'lib/amp/templates/template.rb', line 100

def render(locals = {}, render_binding = binding)
  # expose this local to make it easier, even if it's nil
  
  case renderer.to_sym
  when :erb
    require 'erb'
    locals_assigns = locals.to_a.collect { |k,v| "#{k} = locals[:#{k}]" }
    eval locals_assigns.join("\n"), render_binding
    
    erb = ERB.new(text, 0, "-")
    erb.result render_binding
  when :haml
    require 'rubygems'
    require 'haml'
    haml = Haml::Engine.new(text)
    haml.render render_binding, locals
  end
end