Mustache is the base class from which your Mustache subclasses should inherit (though it can be used on its own).
The typical Mustache workflow is as follows:
Create a template: stats.mustache
Instantiate an instance: view = Stats.new
Render that instance: view.render
You can skip the instantiation by calling `Stats.render` directly.
While Mustache will do its best to load and render a template for you, this process is completely customizable using a few options.
All settings can be overriden at the class level.
For example, going with the above example, we can use `Stats.template_path = “/usr/local/templates”` to specify the path Mustache uses to find templates.
Here are the available options:
The `template_path` setting determines the path Mustache uses when looking for a template. By default it is “.” Setting it to /usr/local/templates, for example, means (given all other settings are default) a Mustache subclass `Stats` will try to load /usr/local/templates/stats.mustache
The `template_extension` is the extension Mustache uses when looking for template files. By default it is “mustache”
You can tell Mustache exactly which template to us with this setting. It can be a relative or absolute path.
template
Sometimes you want Mustache to render a string, not a file. In those cases you may set the `template` setting. For example:
>> Mustache.render("Hello {{planet}}", :planet => "World!") => "Hello World!"
The `template` setting is also available on instances.
view = Mustache.new view.template = "Hi, {{person}}!" view[:person] = 'Mom' view.render # => Hi, mom!
To make life easy on those developing Mustache plugins for web frameworks or other libraries, Mustache will attempt to load view classes (i.e. Mustache subclasses) using the `view_class` class method. The `view_namespace` tells Mustache under which constant view classes live. By default it is `Object`.
Similar to `template_path`, the `view_path` option tells Mustache where to look for files containing view classes when using the `view_class` method.
template_partial => TemplatePartial
# File lib/mustache.rb, line 264 def self.classify(underscored) underscored.split(/[-_]/).map do |part| part[0] = part[0].chr.upcase; part end.join end
Has this template already been compiled? Compilation is somewhat expensive so it may be useful to check this before attempting it.
# File lib/mustache.rb, line 254 def self.compiled? @template.is_a? Template end
Return the value of the configuration setting on the superclass, or return the default.
attr_name - Symbol name of the attribute. It should match the instance variable. default - Default value to use if the superclass does not respond.
Returns the inherited or default configuration setting.
# File lib/mustache.rb, line 298 def self.inheritable_config_for(attr_name, default) superclass.respond_to?(attr_name) ? superclass.send(attr_name) : default end
Given a name, attempts to read a file and return the contents as a string. The file is not rendered, so it might contain {{mustaches}}.
Call `render` if you need to process it.
# File lib/mustache.rb, line 105 def self.partial(name) File.read("#{template_path}/#{name}.#{template_extension}") end
Alias for `template_path`
# File lib/mustache.rb, line 128 def self.path template_path end
Alias for `template_path`
# File lib/mustache.rb, line 133 def self.path=(path) self.template_path = path end
# File lib/mustache.rb, line 248 def self.raise_on_context_miss=(boolean) @raise_on_context_miss = boolean end
Should an exception be raised when we cannot find a corresponding method or key in the current context? By default this is false to emulate ctemplate's behavior, but it may be useful to enable when debugging or developing.
If set to true and there is a context miss, `Mustache::ContextMiss` will be raised.
# File lib/mustache.rb, line 244 def self.raise_on_context_miss? @raise_on_context_miss end
Helper method for quickly instantiating and rendering a view.
# File lib/mustache.rb, line 74 def self.render(*args) new.render(*args) end
Given a file name and an optional context, attempts to load and render the file as a template.
# File lib/mustache.rb, line 90 def self.render_file(name, context = {}) render(partial(name), context) end
The template is the actual string Mustache uses as its template. There is a bit of magic here: what we get back is actually a Mustache::Template object here, but you can still safely use `template=` with a string.
# File lib/mustache.rb, line 173 def self.template @template ||= templateify(File.read(template_file)) end
# File lib/mustache.rb, line 177 def self.template=(template) @template = templateify(template) end
A Mustache template's default extension is 'mustache'
# File lib/mustache.rb, line 138 def self.template_extension @template_extension ||= inheritable_config_for :template_extension, 'mustache' end
# File lib/mustache.rb, line 142 def self.template_extension=(template_extension) @template_extension = template_extension @template = nil end
The template file is the absolute path of the file Mustache will use as its template. By default it's ./class_name.mustache
# File lib/mustache.rb, line 160 def self.template_file @template_file || "#{path}/#{template_name}.#{template_extension}" end
# File lib/mustache.rb, line 164 def self.template_file=(template_file) @template_file = template_file @template = nil end
The template name is the Mustache template file without any extension or other information. Defaults to `class_name`.
# File lib/mustache.rb, line 149 def self.template_name @template_name || underscore end
# File lib/mustache.rb, line 153 def self.template_name=(template_name) @template_name = template_name @template = nil end
The template path informs your Mustache subclass where to look for its corresponding template. By default it's the current directory (“.”)
# File lib/mustache.rb, line 118 def self.template_path @template_path ||= inheritable_config_for :template_path, '.' end
# File lib/mustache.rb, line 122 def self.template_path=(path) @template_path = File.expand_path(path) @template = nil end
Turns a string into a Mustache::Template. If passed a Template, returns it.
# File lib/mustache.rb, line 283 def self.templateify(obj) if obj.is_a?(Template) obj else Template.new(obj.to_s) end end
Alias for `render`
# File lib/mustache.rb, line 79 def self.to_html(*args) render(*args) end
Alias for `render`
# File lib/mustache.rb, line 84 def self.to_text(*args) render(*args) end
TemplatePartial => template_partial Takes a string but defaults to using the current class' name.
# File lib/mustache.rb, line 272 def self.underscore(classified = name) classified = name if classified.to_s.empty? classified = superclass.name if classified.to_s.empty? string = classified.dup.split('::').last string[0] = string[0].chr.downcase string.gsub(/[A-Z]/) { |s| "_#{s.downcase}"} end
When given a symbol or string representing a class, will try to produce an appropriate view class. e.g.
Mustache.view_namespace = Hurl::Views Mustache.view_class(:Partial) # => Hurl::Views::Partial
# File lib/mustache.rb, line 207 def self.view_class(name) if name != classify(name.to_s) name = classify(name.to_s) end # Emptiness begets emptiness. if name.to_s == '' return Mustache end file_name = underscore(name) namespace = view_namespace if namespace.const_defined?(:Views) && namespace::Views.const_defined?(name) namespace::Views.const_get(name) elsif namespace.const_defined?(name) namespace.const_get(name) elsif File.exists?(file = "#{view_path}/#{file_name}.rb") require "#{file}".chomp('.rb') if namespace.const_defined?(:Views) namespace::Views.const_get(name) else namespace.const_get(name) end else Mustache end rescue NameError Mustache end
The constant under which Mustache will look for views. By default it's `Object`, but it might be nice to set it to something like `Hurl::Views` if your app's main namespace is `Hurl`.
# File lib/mustache.rb, line 184 def self.view_namespace @view_namespace ||= inheritable_config_for(:view_namespace, Object) end
# File lib/mustache.rb, line 188 def self.view_namespace=(namespace) @view_namespace = namespace end
Mustache searches the view path for .rb files to require when asked to find a view class. Defaults to “.”
# File lib/mustache.rb, line 194 def self.view_path @view_path ||= inheritable_config_for(:view_path, '.') end
# File lib/mustache.rb, line 198 def self.view_path=(path) @view_path = path end
# File lib/mustache.rb, line 338 def []=(key, value) context[key.to_sym] = value end
Has this instance or its class already compiled a template?
# File lib/mustache.rb, line 259 def compiled? (@template && @template.is_a?(Template)) || self.class.compiled? end
A helper method which gives access to the context at a given time. Kind of a hack for now, but useful when you're in an iterating section and want access to the hash currently being iterated over.
# File lib/mustache.rb, line 324 def context @context ||= Context.new(self) end
Override this in your subclass if you want to do fun things like reading templates from a database. It will be rendered by the context, so all you need to do is return a string.
# File lib/mustache.rb, line 112 def partial(name) self.class.partial(name) end
Instance level version of `Mustache.raise_on_context_miss?`
# File lib/mustache.rb, line 316 def raise_on_context_miss? self.class.raise_on_context_miss? || @raise_on_context_miss end
Parses our fancy pants template file and returns normal file with all special {{tags}} and {{#sections}}replaced{{/sections}}.
# File lib/mustache.rb, line 344 def render(data = template, ctx = {}) tpl = templateify(data) return tpl.render(context) if ctx == {} begin context.push(ctx) tpl.render(context) ensure context.pop end end
Given a file name and an optional context, attempts to load and render the file as a template.
# File lib/mustache.rb, line 96 def render_file(name, context = {}) self.class.render_file(name, context) end
The template can be set at the instance level.
# File lib/mustache.rb, line 307 def template @template ||= self.class.template end
# File lib/mustache.rb, line 311 def template=(template) @template = templateify(template) end
# File lib/mustache.rb, line 302 def templateify(obj) self.class.templateify(obj) end