Class: Liquid::Template

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

Overview

Templates are central to liquid. Interpretating templates is a two step process. First you compile the source code you got. During compile time some extensive error checking is performed. your code should expect to get some SyntaxErrors.

After you have a compiled template you can then render it. You can use a compiled template over and over again and keep it cached.

Example:

template = Liquid::Template.parse(source)
template.render('user_name' => 'bob')

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(environment: Environment.default) ⇒ Template

Returns a new instance of Template.



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# File 'lib/liquid/template.rb', line 89

def initialize(environment: Environment.default)
  @environment = environment
  @rethrow_errors  = false
  @resource_limits = ResourceLimits.new(environment.default_resource_limits)
end

Instance Attribute Details

#name ⇒ Object

Returns the value of attribute name.



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# File 'lib/liquid/template.rb', line 18

def name
  @name
end

#profiler ⇒ Object (readonly)

Returns the value of attribute profiler.



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# File 'lib/liquid/template.rb', line 21

def profiler
  @profiler
end

#resource_limits ⇒ Object (readonly)

Returns the value of attribute resource_limits.



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# File 'lib/liquid/template.rb', line 19

def resource_limits
  @resource_limits
end

#root ⇒ Object

Returns the value of attribute root.



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# File 'lib/liquid/template.rb', line 18

def root
  @root
end

#warnings ⇒ Object (readonly)

Returns the value of attribute warnings.



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# File 'lib/liquid/template.rb', line 19

def warnings
  @warnings
end

Class Method Details

.default_exception_renderer ⇒ Object 



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# File 'lib/liquid/template.rb', line 42

def default_exception_renderer
  Environment.default.exception_renderer
end

.default_exception_renderer=(renderer) ⇒ Object 



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# File 'lib/liquid/template.rb', line 37

def default_exception_renderer=(renderer)
  Deprecations.warn("Template.default_exception_renderer=", "Environment#exception_renderer=")
  Environment.default.exception_renderer = renderer
end

.default_resource_limits ⇒ Object 



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# File 'lib/liquid/template.rb', line 76

def default_resource_limits
  Environment.default.default_resource_limits
end

.error_mode ⇒ Object 



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# File 'lib/liquid/template.rb', line 33

def error_mode
  Environment.default.error_mode
end

.error_mode=(mode) ⇒ Object

Sets how strict the parser should be. :lax acts like liquid 2.5 and silently ignores malformed tags in most cases. :warn is the default and will give deprecation warnings when invalid syntax is used. :strict will enforce correct syntax.



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# File 'lib/liquid/template.rb', line 28

def error_mode=(mode)
  Deprecations.warn("Template.error_mode=", "Environment#error_mode=")
  Environment.default.error_mode = mode
end

.file_system ⇒ Object 



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# File 'lib/liquid/template.rb', line 51

def file_system
  Environment.default.file_system
end

.file_system=(file_system) ⇒ Object 



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# File 'lib/liquid/template.rb', line 46

def file_system=(file_system)
  Deprecations.warn("Template.file_system=", "Environment#file_system=")
  Environment.default.file_system = file_system
end

.parse(source, options = {}) ⇒ Object

creates a new Template object from liquid source code To enable profiling, pass in profile: true as an option. See Liquid::Profiler for more information



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# File 'lib/liquid/template.rb', line 83

def parse(source, options = {})
  environment = options[:environment] || Environment.default
  new(environment: environment).parse(source, options)
end

.register_filter(mod) ⇒ Object

Pass a module with filter methods which should be available to all liquid views. Good for registering the standard library



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# File 'lib/liquid/template.rb', line 66

def register_filter(mod)
  Deprecations.warn("Template.register_filter", "Environment#register_filter")
  Environment.default.register_filter(mod)
end

.register_tag(name, klass) ⇒ Object 



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# File 'lib/liquid/template.rb', line 59

def register_tag(name, klass)
  Deprecations.warn("Template.register_tag", "Environment#register_tag")
  Environment.default.register_tag(name, klass)
end

.tags ⇒ Object 



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# File 'lib/liquid/template.rb', line 55

def tags
  Environment.default.tags
end

Instance Method Details

#assigns ⇒ Object 



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# File 'lib/liquid/template.rb', line 114

def assigns
  @assigns ||= {}
end

#errors ⇒ Object 



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# File 'lib/liquid/template.rb', line 122

def errors
  @errors ||= []
end

#instance_assigns ⇒ Object 



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# File 'lib/liquid/template.rb', line 118

def instance_assigns
  @instance_assigns ||= {}
end

#parse(source, options = {}) ⇒ Object

Parse source code. Returns self for easy chaining



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# File 'lib/liquid/template.rb', line 97

def parse(source, options = {})
  parse_context = configure_options(options)
  source = source.to_s.to_str

  unless source.valid_encoding?
    raise TemplateEncodingError, parse_context.locale.t("errors.syntax.invalid_template_encoding")
  end

  tokenizer     = parse_context.new_tokenizer(source, start_line_number: @line_numbers && 1)
  @root         = Document.parse(tokenizer, parse_context)
  self
end

#registers ⇒ Object 



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# File 'lib/liquid/template.rb', line 110

def registers
  @registers ||= {}
end

#render(*args) ⇒ Object

Render takes a hash with local variables.

if you use the same filters over and over again consider registering them globally with Template.register_filter

if profiling was enabled in Template#parse then the resulting profiling information will be available via Template#profiler

Following options can be passed:

* <tt>filters</tt> : array with local filters
* <tt>registers</tt> : hash with register variables. Those can be accessed from
  filters and tags and might be useful to integrate liquid more with its host application



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# File 'lib/liquid/template.rb', line 140

def render(*args)
  return '' if @root.nil?

  context = case args.first
  when Liquid::Context
    c = args.shift

    if @rethrow_errors
      c.exception_renderer = Liquid::RAISE_EXCEPTION_LAMBDA
    end

    c
  when Liquid::Drop
    drop         = args.shift
    drop.context = Context.new([drop, assigns], instance_assigns, registers, @rethrow_errors, @resource_limits, {}, @environment)
  when Hash
    Context.new([args.shift, assigns], instance_assigns, registers, @rethrow_errors, @resource_limits, {}, @environment)
  when nil
    Context.new(assigns, instance_assigns, registers, @rethrow_errors, @resource_limits, {}, @environment)
  else
    raise ArgumentError, "Expected Hash or Liquid::Context as parameter"
  end

  output = nil

  case args.last
  when Hash
    options = args.pop
    output  = options[:output] if options[:output]
    static_registers = context.registers.static

    options[:registers]&.each do |key, register|
      static_registers[key] = register
    end

    apply_options_to_context(context, options)
  when Module, Array
    context.add_filters(args.pop)
  end

  # Retrying a render resets resource usage
  context.resource_limits.reset

  if @profiling && context.profiler.nil?
    @profiler = context.profiler = Liquid::Profiler.new
  end

  context.template_name ||= name

  begin
    # render the nodelist.
    @root.render_to_output_buffer(context, output || +'')
  rescue Liquid::MemoryError => e
    context.handle_error(e)
  ensure
    @errors = context.errors
  end
end

#render!(*args) ⇒ Object 



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# File 'lib/liquid/template.rb', line 199

def render!(*args)
  @rethrow_errors = true
  render(*args)
end

#render_to_output_buffer(context, output) ⇒ Object 



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# File 'lib/liquid/template.rb', line 204

def render_to_output_buffer(context, output)
  render(context, output: output)
end