2012-05-27 14:18:35 +02:00
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.. _howto-scala:
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######################
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HowTo: Common Patterns
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######################
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This section lists common actor patterns which have been found to be useful,
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elegant or instructive. Anything is welcome, example topics being message
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routing strategies, supervision patterns, restart handling, etc. As a special
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bonus, additions to this section are marked with the contributor’s name, and it
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would be nice if every Akka user who finds a recurring pattern in his or her
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code could share it for the profit of all. Where applicable it might also make
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sense to add to the ``akka.pattern`` package for creating an `OTP-like library
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<http://www.erlang.org/doc/man_index.html>`_.
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2012-08-20 17:24:40 +02:00
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Throttling Messages
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===================
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Contributed by: Kaspar Fischer
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A message throttler that ensures that messages are not sent out at too high a rate.
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The pattern is described `here <http://letitcrash.com/post/28901663062/throttling-messages-in-akka-2>`_.
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Balancing Workload Across Nodes
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===============================
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Contributed by: Derek Wyatt
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Often times, people want the functionality of the BalancingDispatcher with the
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stipulation that the Actors doing the work have distinct Mailboxes on remote
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nodes. In this post we’ll explore the implementation of such a concept.
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The pattern is described `here <http://letitcrash.com/post/29044669086/balancing-workload-across-nodes-with-akka-2>`_.
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Ordered Termination
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===================
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Contributed by: Derek Wyatt
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When an Actor stops, its children stop in an undefined order. Child termination is
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asynchronous and thus non-deterministic.
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If an Actor has children that have order dependencies, then you might need to ensure
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a particular shutdown order of those children so that their postStop() methods get
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called in the right order.
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The pattern is described `here <http://letitcrash.com/post/29773618510/an-akka-2-terminator>`_.
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2012-05-27 14:18:35 +02:00
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Template Pattern
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================
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*Contributed by: N. N.*
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This is an especially nice pattern, since it does even come with some empty example code:
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.. includecode:: code/docs/pattern/ScalaTemplate.scala
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:include: all-of-it
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:exclude: uninteresting-stuff
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.. note::
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Spread the word: this is the easiest way to get famous!
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Please keep this pattern at the end of this file.
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