Merb::Slices

Constants

VERSION

Public Class Methods

[](module_name) click to toggle source

Retrieve a slice module by name

@param <to_s> The slice module to check for. @return <Module> The slice module itself.

# File lib/merb-slices/module.rb, line 10
def [](module_name)
  Object.full_const_get(module_name.to_s) if exists?(module_name)
end
activate(slice_module) click to toggle source

Activate a Slice module at runtime

Looks for previously registered slices; then searches :search_path for matches.

@param slice_module<to_s> Usually a string of version of the slice module name.

# File lib/merb-slices/module.rb, line 89
def activate(slice_module)  
  unless slice_file = self.files[slice_module.to_s]
    module_name_underscored = slice_module.to_s.snake_case.escape_regexp
    module_name_dasherized  = module_name_underscored.tr('_', '-').escape_regexp
    regexp = Regexp.new(/\/(#{module_name_underscored}|#{module_name_dasherized})\/lib\/(#{module_name_underscored}|#{module_name_dasherized})\.rb$/)
    slice_file = slice_files_from_search_path.find { |path| path.match(regexp) } # from search path(s)
  end
  activate_by_file(slice_file) if slice_file
rescue => e
  Merb.logger.error!("Failed to activate slice #{slice_module} (#{e.message})")
end
activate_by_file(slice_file) click to toggle source

Register a Slice by its gem/lib init file path and activate it at runtime

Normally slices are loaded using BootLoaders on application startup. This method gives you the possibility to add slices at runtime, all without restarting your app. Together with deactivate it allows you to enable/disable slices at any time. The router is reloaded to incorporate any changes. Disabled slices will be skipped when routes are regenerated.

@param slice_file<String> The path of the gem ‘init file’

@example Merb::Slices.activate_by_file(‘/path/to/gems/slice-name/lib/slice-name.rb’)

# File lib/merb-slices/module.rb, line 113
def activate_by_file(slice_file)
  Merb::Slices::Loader.load_classes(slice_file)
  slice = register(slice_file, false) # just to get module by slice_file
  slice.load_slice # load the slice
  Merb::Slices::Loader.reload_router!
  slice.init     if slice.respond_to?(:init)
  slice.activate if slice.respond_to?(:activate) && slice.routed?
  slice
rescue
  Merb::Slices::Loader.reload_router!
end
Also aliased as: register_and_load
config() click to toggle source

@return <Hash>

The configuration loaded from Merb.root / "config/slices.yml" or, if
the load fails, an empty hash.
# File lib/merb-slices/module.rb, line 192
def config
  @config ||= begin
    empty_hash = Hash.new { |h,k| h[k] = {} }
    if File.exists?(Merb.root / "config" / "slices.yml")
      require "yaml"
      YAML.load(File.read(Merb.root / "config" / "slices.yml")) || empty_hash
    else
      empty_hash
    end
  end
end
deactivate(slice_module) click to toggle source

Deactivate a Slice module at runtime

@param slice_module<to_s> The Slice module to unregister.

# File lib/merb-slices/module.rb, line 129
def deactivate(slice_module)
  if slice = self[slice_module]
    slice.deactivate if slice.respond_to?(:deactivate) && slice.routed?
    unregister(slice)
  end
end
deactivate_by_file(slice_file) click to toggle source

Deactivate a Slice module at runtime by specifying its slice file

@param slice_file<String> The Slice location of the slice init file to unregister.

# File lib/merb-slices/module.rb, line 139
def deactivate_by_file(slice_file)
  if slice = self.slices.find { |s| s.file == slice_file }
    deactivate(slice.name)
  end
end
each_slice(&block) click to toggle source

Iterate over all registered slices

By default iterates alphabetically over all registered modules. If Merb::Plugins.config[:queue] is set, only the defined modules are loaded in the given order. This can be used to selectively load slices, and also maintain load-order for slices that depend on eachother.

@yield Iterate over known slices and pass in the slice module. @yieldparam module<Module> The Slice module.

# File lib/merb-slices/module.rb, line 254
def each_slice(&block)
  loadable_slices = Merb::Plugins.config[:merb_slices].key?(:queue) ? Merb::Plugins.config[:merb_slices][:queue] : slice_names
  loadable_slices.each do |module_name|
    if mod = self[module_name]
      block.call(mod)
    end
  end
end
exists?(module_name) click to toggle source

Check whether a Slice exists

@param <to_s> The slice module to check for.

# File lib/merb-slices/module.rb, line 223
def exists?(module_name)
  const_name = module_name.to_s.camel_case
  slice_names.include?(const_name) && Object.const_defined?(const_name)
end
filename2module(slice_file) click to toggle source

Helper method to transform a slice filename to a module Symbol

# File lib/merb-slices/module.rb, line 15
def filename2module(slice_file)
  File.basename(slice_file, '.rb').gsub('-', '_').camel_case.to_sym
end
files() click to toggle source

A lookup for finding a Slice module’s slice file path

@return <Hash> A Hash mapping module names to slice files. @note This is unaffected by deactivating a slice; used to reload slices by name.

# File lib/merb-slices/module.rb, line 240
def files
  @files ||= {}
end
named_routes() click to toggle source

@return <Hash>

A Hash mapping between slice identifiers and non-prefixed named routes.
# File lib/merb-slices/module.rb, line 185
def named_routes
  @named_routes ||= {}
end
paths() click to toggle source

A lookup for finding a Slice module’s path

@return <Hash> A Hash mapping module names to root paths. @note Whenever a slice is deactivated, its path is removed from the lookup.

# File lib/merb-slices/module.rb, line 232
def paths
  @paths ||= {}
end
register(slice_file, force = true) click to toggle source

Register a Slice by its gem/lib path for loading at startup

This is referenced from gems/<slice-gem-x.x.x>/lib/<slice-gem>.rb Which gets loaded for any gem. The name of the file is used to extract the Slice module name.

@param slice_file<String> The path of the gem ‘init file’ @param force<Boolean> Whether to overwrite currently registered slice or not.

@return <Module> The Slice module that has been setup.

@example Merb::Slices::register(__FILE__) @example Merb::Slices::register(‘/path/to/my-slice/lib/my-slice.rb’)

# File lib/merb-slices/module.rb, line 32
def register(slice_file, force = true)
  # do what filename2module does, but with intermediate variables
  identifier  = File.basename(slice_file, '.rb')
  underscored = identifier.gsub('-', '_')
  module_name = underscored.camel_case
  slice_path  = File.expand_path(File.dirname(slice_file) + '/..')
  # check if slice_path exists instead of just the module name - more flexible
  if !self.paths.include?(slice_path) || force
    Merb.logger.verbose!("Registered slice '#{module_name}' located at #{slice_path}") if force
    self.files[module_name] = slice_file
    self.paths[module_name] = slice_path
    slice_mod = setup_module(module_name)
    slice_mod.identifier = identifier
    slice_mod.identifier_sym = underscored.to_sym
    slice_mod.root = slice_path
    slice_mod.file = slice_file
    slice_mod.registered
    slice_mod
  else
    Merb.logger.info!("Already registered slice '#{module_name}' located at #{slice_path}")
    Object.full_const_get(module_name)
  end
end
register_and_load(slice_file) click to toggle source
Alias for: activate_by_file
register_slices_from_search_path!() click to toggle source

Look for any slices in Merb.root / ‘slices’ (the default) or if given, Merb::Plugins.config[:search_path] (String/Array)

# File lib/merb-slices/module.rb, line 58
def register_slices_from_search_path!
  slice_files_from_search_path.each do |slice_file|
    absolute_path = File.expand_path(slice_file)
    Merb.logger.info!("Found slice '#{File.basename(absolute_path, '.rb')}' in search path at #{absolute_path.relative_path_from(Merb.root)}")
    Merb::Slices::Loader.load_classes(absolute_path)
  end
end
reload(slice_module) click to toggle source

Reload a Slice at runtime

@param slice_module<to_s> The Slice module to reload.

# File lib/merb-slices/module.rb, line 148
def reload(slice_module)
  if slice = self[slice_module]
    deactivate slice.name
    activate_by_file slice.file
  end
end
reload_by_file(slice_file) click to toggle source

Reload a Slice at runtime by specifying its slice file

@param slice_file<String> The Slice location of the slice init file to reload.

# File lib/merb-slices/module.rb, line 158
def reload_by_file(slice_file)
  if slice = self.slices.find { |s| s.file == slice_file }
    reload(slice.name)
  end
end
slice_files_from_search_path() click to toggle source

Slice file locations from all search paths; this default to host-app/slices.

Look for any slices in those default locations or if given, Merb::Plugins.config[:search_path] (String/Array). Specify files, glob patterns or paths containing slices.

# File lib/merb-slices/module.rb, line 268
def slice_files_from_search_path
  search_paths = Array(Merb::Plugins.config[:merb_slices][:search_path] || [Merb.root / "slices"])
  search_paths.inject([]) do |files, path|
    # handle both Pathname and String
    path = path.to_s
    if File.file?(path) && File.extname(path) == ".rb"
      files << path
    elsif path.include?("*")
      files += glob_search_path(path)
    elsif File.directory?(path)
      files += glob_search_path(path / "**/lib/*.rb")
    end
    files
  end
end
slice_names() click to toggle source

All registered Slice module names

@return <Array> A sorted array of all slice module names.

# File lib/merb-slices/module.rb, line 216
def slice_names
  self.paths.keys.sort
end
slices() click to toggle source

All registered Slice modules

@return <Array> A sorted array of all slice modules.

# File lib/merb-slices/module.rb, line 207
def slices
  slice_names.map do |name|
    Object.full_const_get(name) rescue nil
  end.compact
end
start_dynamic_loader!(interval = nil) click to toggle source

Watch all specified search paths to dynamically load/unload slices at runtime

If a valid slice is found it’s automatically registered and activated; once a slice is removed (or renamed to not match the convention), it will be unregistered and deactivated. Runs in a Thread.

@example Merb::BootLoader.after_app_loads { Merb::Slices.start_dynamic_loader! }

@param interval<Numeric>

The interval in seconds of checking the search path(s) for changes.
# File lib/merb-slices/module.rb, line 174
def start_dynamic_loader!(interval = nil)
  DynamicLoader.start(interval)
end
stop_dynamic_loader!() click to toggle source

Stop watching search paths to dynamically load/unload slices at runtime

# File lib/merb-slices/module.rb, line 179
def stop_dynamic_loader!
  DynamicLoader.stop
end
unregister(slice_module) click to toggle source

Unregister a Slice at runtime

This clears the slice module from ObjectSpace and reloads the router. Since the router doesn’t add routes for any disabled slices this will correctly reflect the app’s routing state.

@param slice_module<to_s> The Slice module to unregister.

# File lib/merb-slices/module.rb, line 73
def unregister(slice_module)
  if (slice = self[slice_module]) && self.paths.delete(module_name = slice.name)
    slice.loadable_files.each { |file| Merb::Slices::Loader.remove_classes_in_file file }
    Object.send(:remove_const, module_name)
    unless Object.const_defined?(module_name)
      Merb.logger.info!("Unregistered slice #{module_name}")
      Merb::Slices::Loader.reload_router!
    end
  end
end

[Validate]

Generated with the Darkfish Rdoc Generator 2.