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<h3>Parent</h3>
<p class="link"><a href="../Object.html">Object</a>
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<!-- Method Quickref -->
<div id="method-list-section" class="nav-section">
<h3>Methods</h3>
<ul class="link-list" role="directory">
<li ><a href="#method-c-finger">::finger</a>
<li ><a href="#method-c-new">::new</a>
<li ><a href="#method-c-primary">::primary</a>
<li ><a href="#method-c-to_a">::to_a</a>
<li ><a href="#method-i-each">#each</a>
<li ><a href="#method-i-lookup_ring">#lookup_ring</a>
<li ><a href="#method-i-lookup_ring_any">#lookup_ring_any</a>
<li ><a href="#method-i-to_a">#to_a</a>
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<main role="main" aria-labelledby="class-Rinda::RingFinger">
<h1 id="class-Rinda::RingFinger" class="class">
class Rinda::RingFinger
</h1>
<section class="description">
<p><a href="RingFinger.html"><code>RingFinger</code></a> is used by <a href="RingServer.html"><code>RingServer</code></a> clients to discover the RingServer's <a href="TupleSpace.html"><code>TupleSpace</code></a>. Typically, all a client needs to do is call <a href="RingFinger.html#method-c-primary"><code>RingFinger.primary</code></a> to retrieve the remote <a href="TupleSpace.html"><code>TupleSpace</code></a>, which it can then begin using.</p>
<p>To find the first available remote TupleSpace:</p>
<pre class="ruby"><span class="ruby-constant">Rinda</span><span class="ruby-operator">::</span><span class="ruby-constant">RingFinger</span>.<span class="ruby-identifier">primary</span>
</pre>
<p>To create a <a href="RingFinger.html"><code>RingFinger</code></a> that broadcasts to a custom list:</p>
<pre class="ruby"><span class="ruby-identifier">rf</span> = <span class="ruby-constant">Rinda</span><span class="ruby-operator">::</span><span class="ruby-constant">RingFinger</span>.<span class="ruby-identifier">new</span> [<span class="ruby-string">'localhost'</span>, <span class="ruby-string">'192.0.2.1'</span>]
<span class="ruby-identifier">rf</span>.<span class="ruby-identifier">primary</span>
</pre>
<p><a href="RingFinger.html"><code>Rinda::RingFinger</code></a> also understands multicast addresses and sets them up properly. This allows you to run multiple RingServers on the same host:</p>
<pre class="ruby"><span class="ruby-identifier">rf</span> = <span class="ruby-constant">Rinda</span><span class="ruby-operator">::</span><span class="ruby-constant">RingFinger</span>.<span class="ruby-identifier">new</span> [<span class="ruby-string">'239.0.0.1'</span>]
<span class="ruby-identifier">rf</span>.<span class="ruby-identifier">primary</span>
</pre>
<p>You can set the hop count (or TTL) for multicast searches using <a href="RingFinger.html#attribute-i-multicast_hops"><code>multicast_hops</code></a>.</p>
<p>If you use IPv6 multicast you may need to set both an address and the outbound interface index:</p>
<pre class="ruby"><span class="ruby-identifier">rf</span> = <span class="ruby-constant">Rinda</span><span class="ruby-operator">::</span><span class="ruby-constant">RingFinger</span>.<span class="ruby-identifier">new</span> [<span class="ruby-string">'ff02::1'</span>]
<span class="ruby-identifier">rf</span>.<span class="ruby-identifier">multicast_interface</span> = <span class="ruby-value">1</span>
<span class="ruby-identifier">rf</span>.<span class="ruby-identifier">primary</span>
</pre>
<p>At this time there is no easy way to get an interface index by name.</p>
</section>
<section id="5Buntitled-5D" class="documentation-section">
<section class="attribute-method-details" class="method-section">
<header>
<h3>Attributes</h3>
</header>
<div id="attribute-i-broadcast_list" class="method-detail">
<div class="method-heading attribute-method-heading">
<span class="method-name">broadcast_list</span><span
class="attribute-access-type">[RW]</span>
</div>
<div class="method-description">
<p>The list of addresses where <a href="RingFinger.html"><code>RingFinger</code></a> will send query packets.</p>
</div>
</div>
<div id="attribute-i-multicast_hops" class="method-detail">
<div class="method-heading attribute-method-heading">
<span class="method-name">multicast_hops</span><span
class="attribute-access-type">[RW]</span>
</div>
<div class="method-description">
<p>Maximum number of hops for sent multicast packets (if using a multicast address in the broadcast list). The default is 1 (same as UDP broadcast).</p>
</div>
</div>
<div id="attribute-i-multicast_interface" class="method-detail">
<div class="method-heading attribute-method-heading">
<span class="method-name">multicast_interface</span><span
class="attribute-access-type">[RW]</span>
</div>
<div class="method-description">
<p>The interface index to send IPv6 multicast packets from.</p>
</div>
</div>
<div id="attribute-i-port" class="method-detail">
<div class="method-heading attribute-method-heading">
<span class="method-name">port</span><span
class="attribute-access-type">[RW]</span>
</div>
<div class="method-description">
<p>The port that <a href="RingFinger.html"><code>RingFinger</code></a> will send query packets to.</p>
</div>
</div>
<div id="attribute-i-primary" class="method-detail">
<div class="method-heading attribute-method-heading">
<span class="method-name">primary</span><span
class="attribute-access-type">[RW]</span>
</div>
<div class="method-description">
<p>Contain the first advertised <a href="TupleSpace.html"><code>TupleSpace</code></a> after <a href="RingFinger.html#method-i-lookup_ring_any"><code>lookup_ring_any</code></a> is called.</p>
</div>
</div>
</section>
<section id="public-class-5Buntitled-5D-method-details" class="method-section">
<header>
<h3>Public Class Methods</h3>
</header>
<div id="method-c-finger" class="method-detail ">
<div class="method-heading">
<span class="method-name">finger</span><span
class="method-args">()</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Creates a singleton <a href="RingFinger.html"><code>RingFinger</code></a> and looks for a <a href="RingServer.html"><code>RingServer</code></a>. Returns the created <a href="RingFinger.html"><code>RingFinger</code></a>.</p>
<div class="method-source-code" id="finger-source">
<pre><span class="ruby-comment"># File lib/rinda/ring.rb, line 288</span>
<span class="ruby-keyword">def</span> <span class="ruby-keyword">self</span>.<span class="ruby-identifier ruby-title">finger</span>
<span class="ruby-keyword">unless</span> <span class="ruby-identifier">@@finger</span>
<span class="ruby-identifier">@@finger</span> = <span class="ruby-keyword">self</span>.<span class="ruby-identifier">new</span>
<span class="ruby-identifier">@@finger</span>.<span class="ruby-identifier">lookup_ring_any</span>
<span class="ruby-keyword">end</span>
<span class="ruby-identifier">@@finger</span>
<span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-c-new" class="method-detail ">
<div class="method-heading">
<span class="method-name">new</span><span
class="method-args">(broadcast_list=@@broadcast_list, port=Ring_PORT)</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Creates a new <a href="RingFinger.html"><code>RingFinger</code></a> that will look for RingServers at <code>port</code> on the addresses in <code>broadcast_list</code>.</p>
<p>If <code>broadcast_list</code> contains a multicast address then multicast queries will be made using the given <a href="RingFinger.html#attribute-i-multicast_hops"><code>multicast_hops</code></a> and multicast_interface.</p>
<div class="method-source-code" id="new-source">
<pre><span class="ruby-comment"># File lib/rinda/ring.rb, line 344</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">initialize</span>(<span class="ruby-identifier">broadcast_list</span>=<span class="ruby-identifier">@@broadcast_list</span>, <span class="ruby-identifier">port</span>=<span class="ruby-constant">Ring_PORT</span>)
<span class="ruby-ivar">@broadcast_list</span> = <span class="ruby-identifier">broadcast_list</span> <span class="ruby-operator">||</span> [<span class="ruby-string">'localhost'</span>]
<span class="ruby-ivar">@port</span> = <span class="ruby-identifier">port</span>
<span class="ruby-ivar">@primary</span> = <span class="ruby-keyword">nil</span>
<span class="ruby-ivar">@rings</span> = []
<span class="ruby-ivar">@multicast_hops</span> = <span class="ruby-value">1</span>
<span class="ruby-ivar">@multicast_interface</span> = <span class="ruby-value">0</span>
<span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-c-primary" class="method-detail ">
<div class="method-heading">
<span class="method-name">primary</span><span
class="method-args">()</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Returns the first advertised <a href="TupleSpace.html"><code>TupleSpace</code></a>.</p>
<div class="method-source-code" id="primary-source">
<pre><span class="ruby-comment"># File lib/rinda/ring.rb, line 299</span>
<span class="ruby-keyword">def</span> <span class="ruby-keyword">self</span>.<span class="ruby-identifier ruby-title">primary</span>
<span class="ruby-identifier">finger</span>.<span class="ruby-identifier">primary</span>
<span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-c-to_a" class="method-detail ">
<div class="method-heading">
<span class="method-name">to_a</span><span
class="method-args">()</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Contains all discovered TupleSpaces except for the primary.</p>
<div class="method-source-code" id="to_a-source">
<pre><span class="ruby-comment"># File lib/rinda/ring.rb, line 306</span>
<span class="ruby-keyword">def</span> <span class="ruby-keyword">self</span>.<span class="ruby-identifier ruby-title">to_a</span>
<span class="ruby-identifier">finger</span>.<span class="ruby-identifier">to_a</span>
<span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
</section>
<section id="public-instance-5Buntitled-5D-method-details" class="method-section">
<header>
<h3>Public Instance Methods</h3>
</header>
<div id="method-i-each" class="method-detail ">
<div class="method-heading">
<span class="method-name">each</span><span
class="method-args">() { |primary| ... }</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Iterates over all discovered TupleSpaces starting with the primary.</p>
<div class="method-source-code" id="each-source">
<pre><span class="ruby-comment"># File lib/rinda/ring.rb, line 364</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">each</span>
<span class="ruby-identifier">lookup_ring_any</span> <span class="ruby-keyword">unless</span> <span class="ruby-ivar">@primary</span>
<span class="ruby-keyword">return</span> <span class="ruby-keyword">unless</span> <span class="ruby-ivar">@primary</span>
<span class="ruby-keyword">yield</span>(<span class="ruby-ivar">@primary</span>)
<span class="ruby-ivar">@rings</span>.<span class="ruby-identifier">each</span> { <span class="ruby-operator">|</span><span class="ruby-identifier">x</span><span class="ruby-operator">|</span> <span class="ruby-keyword">yield</span>(<span class="ruby-identifier">x</span>) }
<span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-i-lookup_ring" class="method-detail ">
<div class="method-heading">
<span class="method-name">lookup_ring</span><span
class="method-args">(timeout=5, &block)</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Looks up RingServers waiting <code>timeout</code> seconds. RingServers will be given <code>block</code> as a callback, which will be called with the remote <a href="TupleSpace.html"><code>TupleSpace</code></a>.</p>
<div class="method-source-code" id="lookup_ring-source">
<pre><span class="ruby-comment"># File lib/rinda/ring.rb, line 376</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">lookup_ring</span>(<span class="ruby-identifier">timeout</span>=<span class="ruby-value">5</span>, <span class="ruby-operator">&</span><span class="ruby-identifier">block</span>)
<span class="ruby-keyword">return</span> <span class="ruby-identifier">lookup_ring_any</span>(<span class="ruby-identifier">timeout</span>) <span class="ruby-keyword">unless</span> <span class="ruby-identifier">block_given?</span>
<span class="ruby-identifier">msg</span> = <span class="ruby-constant">Marshal</span>.<span class="ruby-identifier">dump</span>([[<span class="ruby-value">:lookup_ring</span>, <span class="ruby-constant">DRbObject</span>.<span class="ruby-identifier">new</span>(<span class="ruby-identifier">block</span>)], <span class="ruby-identifier">timeout</span>])
<span class="ruby-ivar">@broadcast_list</span>.<span class="ruby-identifier">each</span> <span class="ruby-keyword">do</span> <span class="ruby-operator">|</span><span class="ruby-identifier">it</span><span class="ruby-operator">|</span>
<span class="ruby-identifier">send_message</span>(<span class="ruby-identifier">it</span>, <span class="ruby-identifier">msg</span>)
<span class="ruby-keyword">end</span>
<span class="ruby-identifier">sleep</span>(<span class="ruby-identifier">timeout</span>)
<span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-i-lookup_ring_any" class="method-detail ">
<div class="method-heading">
<span class="method-name">lookup_ring_any</span><span
class="method-args">(timeout=5)</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Returns the first found remote <a href="TupleSpace.html"><code>TupleSpace</code></a>. Any further recovered TupleSpaces can be found by calling <code>to_a</code>.</p>
<div class="method-source-code" id="lookup_ring_any-source">
<pre><span class="ruby-comment"># File lib/rinda/ring.rb, line 390</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">lookup_ring_any</span>(<span class="ruby-identifier">timeout</span>=<span class="ruby-value">5</span>)
<span class="ruby-identifier">queue</span> = <span class="ruby-constant">Thread</span><span class="ruby-operator">::</span><span class="ruby-constant">Queue</span>.<span class="ruby-identifier">new</span>
<span class="ruby-constant">Thread</span>.<span class="ruby-identifier">new</span> <span class="ruby-keyword">do</span>
<span class="ruby-keyword">self</span>.<span class="ruby-identifier">lookup_ring</span>(<span class="ruby-identifier">timeout</span>) <span class="ruby-keyword">do</span> <span class="ruby-operator">|</span><span class="ruby-identifier">ts</span><span class="ruby-operator">|</span>
<span class="ruby-identifier">queue</span>.<span class="ruby-identifier">push</span>(<span class="ruby-identifier">ts</span>)
<span class="ruby-keyword">end</span>
<span class="ruby-identifier">queue</span>.<span class="ruby-identifier">push</span>(<span class="ruby-keyword">nil</span>)
<span class="ruby-keyword">end</span>
<span class="ruby-ivar">@primary</span> = <span class="ruby-identifier">queue</span>.<span class="ruby-identifier">pop</span>
<span class="ruby-identifier">raise</span>(<span class="ruby-string">'RingNotFound'</span>) <span class="ruby-keyword">if</span> <span class="ruby-ivar">@primary</span>.<span class="ruby-identifier">nil?</span>
<span class="ruby-constant">Thread</span>.<span class="ruby-identifier">new</span> <span class="ruby-keyword">do</span>
<span class="ruby-keyword">while</span> <span class="ruby-identifier">it</span> = <span class="ruby-identifier">queue</span>.<span class="ruby-identifier">pop</span>
<span class="ruby-ivar">@rings</span>.<span class="ruby-identifier">push</span>(<span class="ruby-identifier">it</span>)
<span class="ruby-keyword">end</span>
<span class="ruby-keyword">end</span>
<span class="ruby-ivar">@primary</span>
<span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-i-to_a" class="method-detail ">
<div class="method-heading">
<span class="method-name">to_a</span><span
class="method-args">()</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Contains all discovered TupleSpaces except for the primary.</p>
<div class="method-source-code" id="to_a-source">
<pre><span class="ruby-comment"># File lib/rinda/ring.rb, line 357</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">to_a</span>
<span class="ruby-ivar">@rings</span>
<span class="ruby-keyword">end</span></pre>
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