Indicates a failure to resolve a name or address.

Indicates a timeout resolving a name or address.

A Source that wraps an IO. See the Source class for method documentation

Wrapper class. Use this class to access the XPath functions.

@private

Rinda error base class

Raised when trying to use a canceled tuple.

Raised when trying to use an expired tuple.

TupleSpaceProxy allows a remote Tuplespace to appear as local.

RingFinger is used by RingServer clients to discover the RingServer’s TupleSpace. Typically, all a client needs to do is call RingFinger.primary to retrieve the remote TupleSpace, which it can then begin using.

To find the first available remote TupleSpace:

Rinda::RingFinger.primary

To create a RingFinger that broadcasts to a custom list:

rf = Rinda::RingFinger.new  ['localhost', '192.0.2.1']
rf.primary

Rinda::RingFinger also understands multicast addresses and sets them up properly. This allows you to run multiple RingServers on the same host:

rf = Rinda::RingFinger.new ['239.0.0.1']
rf.primary

You can set the hop count (or TTL) for multicast searches using multicast_hops.

If you use IPv6 multicast you may need to set both an address and the outbound interface index:

rf = Rinda::RingFinger.new ['ff02::1']
rf.multicast_interface = 1
rf.primary

At this time there is no easy way to get an interface index by name.

RingProvider uses a RingServer advertised TupleSpace as a name service. TupleSpace clients can register themselves with the remote TupleSpace and look up other provided services via the remote TupleSpace.

Services are registered with a tuple of the format [:name, klass, DRbObject, description].

A NotifyTemplateEntry is returned by TupleSpace#notify and is notified of TupleSpace changes. You may receive either your subscribed event or the ‘close’ event when iterating over notifications.

See TupleSpace#notify_event for valid notification types.

Example

ts = Rinda::TupleSpace.new
observer = ts.notify 'write', [nil]

Thread.start do
  observer.each { |t| p t }
end

3.times { |i| ts.write [i] }

Outputs:

['write', [0]]
['write', [1]]
['write', [2]]

The Tuplespace manages access to the tuples it contains, ensuring mutual exclusion requirements are met.

The sec option for the write, take, move, read and notify methods may either be a number of seconds or a Renewer object.

RSS 2.0 support

RSS has three different versions. This module contains support for version 2.0

Producing RSS 2.0

Producing our own RSS feeds is easy as well. Let’s make a very basic feed:

require "rss"

rss = RSS::Maker.make("2.0") do |maker|
  maker.channel.language = "en"
  maker.channel.author = "matz"
  maker.channel.updated = Time.now.to_s
  maker.channel.link = "http://www.ruby-lang.org/en/feeds/news.rss"
  maker.channel.title = "Example Feed"
  maker.channel.description = "A longer description of my feed."
  maker.items.new_item do |item|
    item.link = "http://www.ruby-lang.org/en/news/2010/12/25/ruby-1-9-2-p136-is-released/"
    item.title = "Ruby 1.9.2-p136 is released"
    item.updated = Time.now.to_s
  end
end

puts rss

As you can see, this is a very Builder-like DSL. This code will spit out an RSS 2.0 feed with one item. If we needed a second item, we’d make another block with maker.items.new_item and build a second one.

The basic error all other RSS errors stem from. Rescue this error if you want to handle any given RSS error and you don’t care about the details.

Since RSS is based on XML, it must have opening and closing tags that match. If they don’t, a MissingTagError will be raised.

Some tags must only exist a specific number of times in a given RSS feed. If a feed has too many occurrences of one of these tags, a TooMuchTagError will be raised.

Certain attributes are required on specific tags in an RSS feed. If a feed is missing one of these attributes, a MissingAttributeError is raised.

RSS does not allow for free-form tag names, so if an RSS feed contains a tag that we don’t know about, an UnknownTagError is raised.

Raised when an unexpected tag is encountered.