module Merb
# Module that is mixed in to all implemented controllers.
module ControllerMixin
def must_support_streaming!
raise(NotImplemented, "Current Rack adapter does not support streaming") unless request.env['rack.streaming']
end
# Renders the block given as a parameter using chunked
# encoding.
#
# ==== Examples
#
# def stream
# prefix = '<p>'
# suffix = "</p>\r\n"
# render_chunked do
# IO.popen("cat /tmp/test.log") do |io|
# done = false
# until done
# sleep 0.3
# line = io.gets.chomp
#
# if line == 'EOF'
# done = true
# else
# send_chunk(prefix + line + suffix)
# end
# end
# end
# end
# end
#
# ==== Parameters
# blk<Proc>::
# A proc that, when called, will use send_chunks to
# send chunks of data down to the server. The chunking will
# terminate once the block returns.
def render_chunked(&blk)
must_support_streaming!
headers['Transfer-Encoding'] = 'chunked'
Proc.new { |response|
@response = response
response.send_status_no_connection_close('')
response.send_header
blk.call
response.write("0\r\n\r\n")
}
end
# Writes a chunk from render_chunked to the response that
# is sent back to the client. This can only be called within
# a render_chunked {} block
#
# ==== Parameters
# data<String>:: a chunk of data to return
def send_chunk(data)
@response.write('%x' % data.size + "\r\n")
@response.write(data + "\r\n")
end
# Returns a +Proc+ that Mongrel can call later, allowing
# Merb to release the thread lock and render another request.
#
# ==== Parameters
# blk<Proc>::
# A proc that should get called outside the mutex,
# and which will return the value to render
def render_deferred(&blk)
must_support_streaming!
Proc.new {|response|
result = blk.call
response.send_status(result.length)
response.send_header
response.write(result)
}
end
# Renders the passed in string, then calls the block outside
# the mutex and after the string has been returned to the client
#
# ==== Parameters
# str<String>:: A +String+ to return to the client
# blk<Proc>:: A proc that should get called once the string has
# been returned
def render_then_call(str, &blk)
must_support_streaming!
Proc.new {
response.send_status(str.length)
response.send_header
response.write(str)
blk.call
}
end
# Redirects to a URL. The +url+ parameter can be either
# a relative URL (e.g., +/posts/34+) or a fully-qualified URL
# (e.g., +http://www.merbivore.com/+).
#
# ==== Parameters
# url<String>:: URL to redirect to; it can be either a relative or
# fully-qualified URL.
def redirect(url)
Merb.logger.info("Redirecting to: #{url}")
self.status = 302
headers['Location'] = url
"<html><body>You are being <a href=\"#{url}\">redirected</a>.</body></html>"
end
# Sends a file over HTTP. When given a path to a file, it will set the
# right headers so that the static file is served directly.
#
# ==== Parameters
# file<String>:: Path to file to send to the client.
def send_file(file, opts={})
opts.update(Merb::Const::DEFAULT_SEND_FILE_OPTIONS.merge(opts))
disposition = opts[:disposition].dup || 'attachment'
disposition << %(; filename="#{opts[:filename] ? opts[:filename] : File.basename(file)}")
headers.update(
'Content-Type' => opts[:type].strip, # fixes a problem with extra '\r' with some browsers
'Content-Disposition' => disposition,
'Content-Transfer-Encoding' => 'binary'
)
File.open(file)
end
# Streams a file over HTTP.
#
# ==== Example
# stream_file( { :filename => file_name,
# :type => content_type,
# :content_length => content_length }) do |response|
# AWS::S3::S3Object.stream(user.folder_name + "-" + user_file.unique_id, bucket_name) do |chunk|
# response.write chunk
# end
# end
#
# ==== Parameters
# opts<Hash>:: A +Hash+ of options (see below)
# stream<Proc>:: A +Proc+ that, when called, will return a +respond_to?(:get_lines)+
# object to stream
#
# ==== Options
# :disposition<String>:: An acceptable value for headers["Content-Disposition"]
# :type<String>:: An acceptable value for headers["Content-Type"]
# :content_length<Numeric>:: An acceptable value for headers["CONTENT-LENGTH"]
# :filename<String>:: An acceptable value for the filename= portion
# of headers["Content-Disposition"]
def stream_file(opts={}, &stream)
must_support_streaming!
opts.update(Merb::Const::DEFAULT_SEND_FILE_OPTIONS.merge(opts))
disposition = opts[:disposition].dup || 'attachment'
disposition << %(; filename="#{opts[:filename]}")
response.headers.update(
'Content-Type' => opts[:type].strip, # fixes a problem with extra '\r' with some browsers
'Content-Disposition' => disposition,
'Content-Transfer-Encoding' => 'binary',
'CONTENT-LENGTH' => opts[:content_length]
)
response.send_status(opts[:content_length])
response.send_header
stream
end
# Uses the nginx specific +X-Accel-Redirect+ header to send
# a file directly from nginx. For more information, see the nginx wiki:
# http://wiki.codemongers.com/NginxXSendfile
#
# ==== Parameters
# file<String>:: Path to file to send to the client
def nginx_send_file(file)
headers['X-Accel-Redirect'] = File.expand_path(file)
return
end
# Sets a cookie to be included in the response. This method is used
# primarily internally in Merb.
#
# If you need to set a cookie, then use the +cookies+ hash.
#
# ==== Parameters
# name<~to_s>:: A name for the cookie
# value<~to_s>:: A value for the cookie
# expires<~gmtime:~strftime>:: An expiration time for the cookie
def set_cookie(name, value, expires)
(headers['Set-Cookie'] ||=[]) << (Merb::Const::SET_COOKIE % [
name.to_s,
::Merb::Request.escape(value.to_s),
# Cookie expiration time must be GMT. See RFC 2109
expires.gmtime.strftime(Merb::Const::COOKIE_EXPIRATION_FORMAT)
])
end
# Marks a cookie as deleted and gives it an expires stamp in
# the past. This method is used primarily internally in Merb.
#
# Use the +cookies+ hash to manipulate cookies instead.
#
# ==== Parameters
# name<~to_s>:: A name for the cookie to delete
def delete_cookie(name)
set_cookie(name, nil, Merb::Const::COOKIE_EXPIRED_TIME)
end
def url(name, rparams={})
Merb::Router.generate(name, rparams,
{ :controller => controller_name,
:action => action_name,
:format => params[:format]
}
)
end
# Escapes the string representation of +obj+ and escapes
# it for use in XML.
#
# ==== Parameter
#
# +obj+ - The object to escape for use in XML.
def escape_xml(obj)
obj.to_s.gsub(/[&<>"']/) { |s| Merb::Const::ESCAPE_TABLE[s] }
end
alias h escape_xml
alias html_escape escape_xml
end
end
) is private.
