Module: Aldebaran::Helpers

Included in:
Base
Defined in:
lib/aldebaran/base.rb

Overview

Methods available to routes, before/after filters, and views.

Defined Under Namespace

Classes: Stream

Instance Method Summary (collapse)

Instance Method Details

- (Object) attachment(filename = nil)

Set the Content-Disposition to "attachment" with the specified filename, instructing the user agents to prompt to save.



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# File 'lib/aldebaran/base.rb', line 203

def attachment(filename=nil)
  response['Content-Disposition'] = 'attachment'
  if filename
    params = '; filename="%s"' % File.basename(filename)
    response['Content-Disposition'] << params
    ext = File.extname(filename)
    content_type(ext) unless response['Content-Type'] or ext.empty?
  end
end

- (Object) back

Sugar for redirect (example: redirect back)



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# File 'lib/aldebaran/base.rb', line 388

def back
  request.referer
end

- (Object) body(value = nil, &block)

Set or retrieve the response body. When a block is given, evaluation is deferred until the body is read with #each.



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# File 'lib/aldebaran/base.rb', line 103

def body(value=nil, &block)
  if block_given?
    def block.each; yield(call) end
    response.body = block
  elsif value
    response.body = value
  else
    response.body
  end
end

- (Object) cache_control(*values)

Specify response freshness policy for HTTP caches (Cache-Control header). Any number of non-value directives (:public, :private, :no_cache, :no_store, :must_revalidate, :proxy_revalidate) may be passed along with a Hash of value directives (:max_age, :min_stale, :s_max_age).

cache_control :public, :must_revalidate, :max_age => 60
=> Cache-Control: public, must-revalidate, max-age=60

See RFC 2616 / 14.9 for more on standard cache control directives: tools.ietf.org/html/rfc2616#section-14.9.1



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# File 'lib/aldebaran/base.rb', line 301

def cache_control(*values)
  if values.last.kind_of?(Hash)
    hash = values.pop
    hash.reject! { |k,v| v == false }
    hash.reject! { |k,v| values << k if v == true }
  else
    hash = {}
  end

  values = values.map { |value| value.to_s.tr('_','-') }
  hash.each do |key, value|
    key = key.to_s.tr('_', '-')
    value = value.to_i if key == "max-age"
    values << [key, value].join('=')
  end

  response['Cache-Control'] = values.join(', ') if values.any?
end

- (Boolean) client_error?

whether or not the status is set to 4xx



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# File 'lib/aldebaran/base.rb', line 408

def client_error?
  status.between? 400, 499
end

- (Object) content_type(type = nil, params = {})

Set the Content-Type of the response body given a media type or file extension.



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# File 'lib/aldebaran/base.rb', line 184

def content_type(type = nil, params={})
  return response['Content-Type'] unless type
  default = params.delete :default
  mime_type = mime_type(type) || default
  fail "Unknown media type: %p" % type if mime_type.nil?
  mime_type = mime_type.dup
  unless params.include? :charset or settings.add_charset.all? { |p| not p === mime_type }
    params[:charset] = params.delete('charset') || settings.default_encoding
  end
  params.delete :charset if mime_type.include? 'charset'
  unless params.empty?
    mime_type << (mime_type.include?(';') ? ', ' : ';')
    mime_type << params.map { |kv| kv.join('=') }.join(', ')
  end
  response['Content-Type'] = mime_type
end

- (Object) error(code, body = nil)

Halt processing and return the error status provided.



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# File 'lib/aldebaran/base.rb', line 150

def error(code, body=nil)
  code, body    = 500, code.to_str if code.respond_to? :to_str
  response.body = body unless body.nil?
  halt code
end

- (Object) etag(value, kind = :strong)

Set the response entity tag (HTTP 'ETag' header) and halt if conditional GET matches. The value argument is an identifier that uniquely identifies the current version of the resource. The kind argument indicates whether the etag should be used as a :strong (default) or :weak cache validator.

When the current request includes an 'If-None-Match' header with a matching etag, execution is immediately halted. If the request method is GET or HEAD, a '304 Not Modified' response is sent.

Raises:

  • (ArgumentError)


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# File 'lib/aldebaran/base.rb', line 371

def etag(value, kind = :strong)
  raise ArgumentError, ":strong or :weak expected" unless [:strong,:weak].include?(kind)
  value = '"%s"' % value
  value = 'W/' + value if kind == :weak
  response['ETag'] = value

  if etags = env['HTTP_IF_NONE_MATCH']
    etags = etags.split(/\s*,\s*/)
    if etags.include?(value) or etags.include?('*')
      halt 304 if request.safe?
    else
      halt 412 unless request.safe?
    end
  end
end

- (Object) expires(amount, *values)

Set the Expires header and Cache-Control/max-age directive. Amount can be an integer number of seconds in the future or a Time object indicating when the response should be considered "stale". The remaining "values" arguments are passed to the #cache_control helper:

expires 500, :public, :must_revalidate
=> Cache-Control: public, must-revalidate, max-age=60
=> Expires: Mon, 08 Jun 2009 08:50:17 GMT


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# File 'lib/aldebaran/base.rb', line 329

def expires(amount, *values)
  values << {} unless values.last.kind_of?(Hash)

  if amount.is_a? Integer
    time    = Time.now + amount.to_i
    max_age = amount
  else
    time    = time_for amount
    max_age = time - Time.now
  end

  values.last.merge!(:max_age => max_age)
  cache_control(*values)

  response['Expires'] = time.httpdate
end

- (Object) headers(hash = nil)

Set multiple response headers with Hash.



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# File 'lib/aldebaran/base.rb', line 162

def headers(hash=nil)
  response.headers.merge! hash if hash
  response.headers
end

- (Boolean) informational?

whether or not the status is set to 1xx



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# File 'lib/aldebaran/base.rb', line 393

def informational?
  status.between? 100, 199
end

- (Object) last_modified(time)

Set the last modified time of the resource (HTTP 'Last-Modified' header) and halt if conditional GET matches. The time argument is a Time, DateTime, or other object that responds to to_time.

When the current request includes an 'If-Modified-Since' header that is equal or later than the time specified, execution is immediately halted with a '304 Not Modified' response.



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# File 'lib/aldebaran/base.rb', line 353

def last_modified(time)
  return unless time
  time = time_for time
  response['Last-Modified'] = time.httpdate
  # compare based on seconds since epoch
  halt 304 if Time.httpdate(env['HTTP_IF_MODIFIED_SINCE']).to_i >= time.to_i
rescue ArgumentError
end

- (Object) logger

Access shared logger object.



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# File 'lib/aldebaran/base.rb', line 173

def logger
  request.logger
end

- (Object) mime_type(type)

Look up a media type by file extension in Rack's mime registry.



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# File 'lib/aldebaran/base.rb', line 178

def mime_type(type)
  Base.mime_type(type)
end

- (Object) not_found(body = nil)

Halt processing and return a 404 Not Found.



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# File 'lib/aldebaran/base.rb', line 157

def not_found(body=nil)
  error 404, body
end

- (Boolean) not_found?

whether or not the status is set to 404



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# File 'lib/aldebaran/base.rb', line 418

def not_found?
  status == 404
end

- (Object) redirect(uri, *args)

Halt processing and redirect to the URI provided.



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# File 'lib/aldebaran/base.rb', line 115

def redirect(uri, *args)
  if env['HTTP_VERSION'] == 'HTTP/1.1' and env["REQUEST_METHOD"] != 'GET'
    status 303
  else
    status 302
  end

  # According to RFC 2616 section 14.30, "the field value consists of a
  # single absolute URI"
  response['Location'] = uri(uri, settings.absolute_redirects?, settings.prefixed_redirects?)
  halt(*args)
end

- (Boolean) redirect?

whether or not the status is set to 3xx



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# File 'lib/aldebaran/base.rb', line 403

def redirect?
  status.between? 300, 399
end

- (Object) send_file(path, opts = {})

Use the contents of the file at path as the response body.



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# File 'lib/aldebaran/base.rb', line 214

def send_file(path, opts={})
  if opts[:type] or not response['Content-Type']
    content_type opts[:type] || File.extname(path), :default => 'application/octet-stream'
  end

  if opts[:disposition] == 'attachment' || opts[:filename]
    attachment opts[:filename] || path
  elsif opts[:disposition] == 'inline'
    response['Content-Disposition'] = 'inline'
  end

  last_modified opts[:last_modified] if opts[:last_modified]

  file      = Rack::File.new nil
  file.path = path
  result    = file.serving env
  result[1].each { |k,v| headers[k] ||= v }
  halt result[0], result[2]
rescue Errno::ENOENT
  not_found
end

- (Boolean) server_error?

whether or not the status is set to 5xx



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# File 'lib/aldebaran/base.rb', line 413

def server_error?
  status.between? 500, 599
end

- (Object) session

Access the underlying Rack session.



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# File 'lib/aldebaran/base.rb', line 168

def session
  request.session
end

- (Object) status(value = nil)

Set or retrieve the response status code.



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# File 'lib/aldebaran/base.rb', line 96

def status(value=nil)
  response.status = value if value
  response.status
end

- (Object) stream(close = true, &block)

Allows to start sending data to the client even though later parts of the response body have not yet been generated.

The close parameter specifies whether Stream#close should be called after the block has been executed. This is only relevant for evented servers like Thin or Rainbows.



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# File 'lib/aldebaran/base.rb', line 286

def stream(close = true, &block)
  scheduler = env['async.callback'] ? EventMachine : Stream
  body Stream.new(scheduler, close, &block)
end

- (Boolean) success?

whether or not the status is set to 2xx



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# File 'lib/aldebaran/base.rb', line 398

def success?
  status.between? 200, 299
end

- (Object) time_for(value)

Generates a Time object from the given value. Used by #expires and #last_modified.



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# File 'lib/aldebaran/base.rb', line 424

def time_for(value)
  if value.respond_to? :to_time
    value.to_time
  elsif value.is_a? Time
    value
  elsif value.respond_to? :new_offset
    # DateTime#to_time does the same on 1.9
    d = value.new_offset 0
    t = Time.utc d.year, d.mon, d.mday, d.hour, d.min, d.sec + d.sec_fraction
    t.getlocal
  elsif value.respond_to? :mday
    # Date#to_time does the same on 1.9
    Time.local(value.year, value.mon, value.mday)
  elsif value.is_a? Numeric
    Time.at value
  else
    Time.parse value.to_s
  end
rescue ArgumentError => boom
  raise boom
rescue Exception
  raise ArgumentError, "unable to convert #{value.inspect} to a Time object"
end

- (Object) uri(addr = nil, absolute = true, add_script_name = true) Also known as: url, to

Generates the absolute URI for a given path in the app. Takes Rack routers and reverse proxies into account.



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# File 'lib/aldebaran/base.rb', line 130

def uri(addr = nil, absolute = true, add_script_name = true)
  return addr if addr =~ /\A[A-z][A-z0-9\+\.\-]*:/
  uri = [host = ""]
  if absolute
    host << "http#{'s' if request.secure?}://"
    if request.forwarded? or request.port != (request.secure? ? 443 : 80)
      host << request.host_with_port
    else
      host << request.host
    end
  end
  uri << request.script_name.to_s if add_script_name
  uri << (addr ? addr : request.path_info).to_s
  File.join uri
end