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1.1 |
=head1 NAME |
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AnyEvent::MP - multi-processing/message-passing framework |
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=head1 SYNOPSIS |
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use AnyEvent::MP; |
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$NODE # contains this node's noderef |
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NODE # returns this node's noderef |
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NODE $port # returns the noderef of the port |
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1.2 |
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snd $port, type => data...; |
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1.22 |
$SELF # receiving/own port id in rcv callbacks |
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1.2 |
rcv $port, smartmatch => $cb->($port, @msg); |
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# examples: |
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rcv $port2, ping => sub { snd $_[0], "pong"; 0 }; |
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rcv $port1, pong => sub { warn "pong received\n" }; |
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snd $port2, ping => $port1; |
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# more, smarter, matches (_any_ is exported by this module) |
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rcv $port, [child_died => $pid] => sub { ... |
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rcv $port, [_any_, _any_, 3] => sub { .. $_[2] is 3 |
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1.1 |
=head1 DESCRIPTION |
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This module (-family) implements a simple message passing framework. |
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Despite its simplicity, you can securely message other processes running |
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on the same or other hosts. |
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1.23 |
For an introduction to this module family, see the L<AnyEvent::MP::Intro> |
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manual page. |
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At the moment, this module family is severly broken and underdocumented, |
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so do not use. This was uploaded mainly to reserve the CPAN namespace - |
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1.23 |
stay tuned! The basic API should be finished, however. |
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1.6 |
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1.2 |
=head1 CONCEPTS |
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=over 4 |
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=item port |
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A port is something you can send messages to (with the C<snd> function). |
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Some ports allow you to register C<rcv> handlers that can match specific |
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messages. All C<rcv> handlers will receive messages they match, messages |
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will not be queued. |
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|
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=item port id - C<noderef#portname> |
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1.2 |
|
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A port id is normaly the concatenation of a noderef, a hash-mark (C<#>) as |
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separator, and a port name (a printable string of unspecified format). An |
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exception is the the node port, whose ID is identical to its node |
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reference. |
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=item node |
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A node is a single process containing at least one port - the node |
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port. You can send messages to node ports to find existing ports or to |
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create new ports, among other things. |
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1.2 |
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Nodes are either private (single-process only), slaves (connected to a |
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master node only) or public nodes (connectable from unrelated nodes). |
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1.2 |
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=item noderef - C<host:port,host:port...>, C<id@noderef>, C<id> |
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A node reference is a string that either simply identifies the node (for |
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private and slave nodes), or contains a recipe on how to reach a given |
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node (for public nodes). |
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This recipe is simply a comma-separated list of C<address:port> pairs (for |
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TCP/IP, other protocols might look different). |
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Node references come in two flavours: resolved (containing only numerical |
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addresses) or unresolved (where hostnames are used instead of addresses). |
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Before using an unresolved node reference in a message you first have to |
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resolve it. |
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1.2 |
=back |
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1.3 |
=head1 VARIABLES/FUNCTIONS |
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1.2 |
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=over 4 |
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1.1 |
=cut |
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package AnyEvent::MP; |
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1.8 |
use AnyEvent::MP::Base; |
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1.2 |
|
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use common::sense; |
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1.2 |
use Carp (); |
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use AE (); |
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use base "Exporter"; |
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our $VERSION = '0.1'; |
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our @EXPORT = qw( |
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NODE $NODE *SELF node_of _any_ |
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resolve_node |
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1.8 |
become_slave become_public |
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1.22 |
snd rcv mon kil reg psub |
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port |
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1.8 |
); |
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1.2 |
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our $SELF; |
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sub _self_die() { |
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my $msg = $@; |
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$msg =~ s/\n+$// unless ref $msg; |
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kil $SELF, die => $msg; |
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} |
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=item $thisnode = NODE / $NODE |
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The C<NODE> function returns, and the C<$NODE> variable contains |
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the noderef of the local node. The value is initialised by a call |
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to C<become_public> or C<become_slave>, after which all local port |
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identifiers become invalid. |
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=item $noderef = node_of $portid |
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Extracts and returns the noderef from a portid or a noderef. |
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=item $cv = resolve_node $noderef |
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Takes an unresolved node reference that may contain hostnames and |
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abbreviated IDs, resolves all of them and returns a resolved node |
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reference. |
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In addition to C<address:port> pairs allowed in resolved noderefs, the |
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following forms are supported: |
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=over 4 |
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=item the empty string |
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An empty-string component gets resolved as if the default port (4040) was |
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specified. |
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=item naked port numbers (e.g. C<1234>) |
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These are resolved by prepending the local nodename and a colon, to be |
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further resolved. |
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=item hostnames (e.g. C<localhost:1234>, C<localhost>) |
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These are resolved by using AnyEvent::DNS to resolve them, optionally |
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looking up SRV records for the C<aemp=4040> port, if no port was |
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specified. |
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=back |
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1.22 |
=item $SELF |
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Contains the current port id while executing C<rcv> callbacks or C<psub> |
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blocks. |
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1.3 |
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1.22 |
=item SELF, %SELF, @SELF... |
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Due to some quirks in how perl exports variables, it is impossible to |
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just export C<$SELF>, all the symbols called C<SELF> are exported by this |
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module, but only C<$SELF> is currently used. |
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1.3 |
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=item snd $portid, type => @data |
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=item snd $portid, @msg |
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1.8 |
Send the given message to the given port ID, which can identify either |
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a local or a remote port, and can be either a string or soemthignt hat |
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stringifies a sa port ID (such as a port object :). |
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While the message can be about anything, it is highly recommended to use a |
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string as first element (a portid, or some word that indicates a request |
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type etc.). |
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1.3 |
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The message data effectively becomes read-only after a call to this |
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function: modifying any argument is not allowed and can cause many |
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problems. |
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The type of data you can transfer depends on the transport protocol: when |
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JSON is used, then only strings, numbers and arrays and hashes consisting |
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of those are allowed (no objects). When Storable is used, then anything |
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that Storable can serialise and deserialise is allowed, and for the local |
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node, anything can be passed. |
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1.22 |
=item kil $portid[, @reason] |
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Kill the specified port with the given C<@reason>. |
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If no C<@reason> is specified, then the port is killed "normally" (linked |
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ports will not be kileld, or even notified). |
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Otherwise, linked ports get killed with the same reason (second form of |
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C<mon>, see below). |
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Runtime errors while evaluating C<rcv> callbacks or inside C<psub> blocks |
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will be reported as reason C<< die => $@ >>. |
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Transport/communication errors are reported as C<< transport_error => |
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$message >>. |
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=item $guard = mon $portid, $cb->(@reason) |
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1.18 |
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1.21 |
=item $guard = mon $portid, $otherport |
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=item $guard = mon $portid, $otherport, @msg |
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1.22 |
Monitor the given port and do something when the port is killed. |
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In the first form, the callback is simply called with any number |
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of C<@reason> elements (no @reason means that the port was deleted |
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"normally"). Note also that I<< the callback B<must> never die >>, so use |
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C<eval> if unsure. |
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In the second form, the other port will be C<kil>'ed with C<@reason>, iff |
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a @reason was specified, i.e. on "normal" kils nothing happens, while |
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under all other conditions, the other port is killed with the same reason. |
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1.20 |
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1.22 |
In the last form, a message of the form C<@msg, @reason> will be C<snd>. |
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Example: call a given callback when C<$port> is killed. |
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mon $port, sub { warn "port died because of <@_>\n" }; |
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Example: kill ourselves when C<$port> is killed abnormally. |
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mon $port, $self; |
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Example: send us a restart message another C<$port> is killed. |
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mon $port, $self => "restart"; |
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1.18 |
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=cut |
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sub mon { |
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1.30 |
my ($noderef, $port) = split /#/, shift, 2; |
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1.18 |
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1.22 |
my $node = $NODE{$noderef} || add_node $noderef; |
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1.18 |
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1.30 |
my $cb = shift; |
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unless (ref $cb) { |
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1.21 |
if (@_) { |
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# send a kill info message |
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my (@msg) = ($cb, @_); |
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$cb = sub { snd @msg, @_ }; |
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} else { |
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# simply kill other port |
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my $port = $cb; |
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1.22 |
$cb = sub { kil $port, @_ if @_ }; |
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1.21 |
} |
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} |
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1.18 |
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$node->monitor ($port, $cb); |
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defined wantarray |
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and AnyEvent::Util::guard { $node->unmonitor ($port, $cb) } |
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} |
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1.21 |
=item $guard = mon_guard $port, $ref, $ref... |
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Monitors the given C<$port> and keeps the passed references. When the port |
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is killed, the references will be freed. |
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Optionally returns a guard that will stop the monitoring. |
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This function is useful when you create e.g. timers or other watchers and |
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want to free them when the port gets killed: |
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$port->rcv (start => sub { |
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my $timer; $timer = mon_guard $port, AE::timer 1, 1, sub { |
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undef $timer if 0.9 < rand; |
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}); |
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}); |
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=cut |
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sub mon_guard { |
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my ($port, @refs) = @_; |
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mon $port, sub { 0 && @refs } |
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} |
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1.24 |
=item lnk $port1, $port2 |
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Link two ports. This is simply a shorthand for: |
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mon $port1, $port2; |
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mon $port2, $port1; |
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It means that if either one is killed abnormally, the other one gets |
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killed as well. |
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1.22 |
=item $local_port = port |
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1.2 |
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1.22 |
Create a new local port object that supports message matching. |
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1.3 |
|
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1.22 |
=item $portid = port { my @msg = @_; $finished } |
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1.10 |
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1.15 |
Creates a "mini port", that is, a very lightweight port without any |
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pattern matching behind it, and returns its ID. |
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The block will be called for every message received on the port. When the |
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callback returns a true value its job is considered "done" and the port |
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will be destroyed. Otherwise it will stay alive. |
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1.17 |
The message will be passed as-is, no extra argument (i.e. no port id) will |
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1.15 |
be passed to the callback. |
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If you need the local port id in the callback, this works nicely: |
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my $port; $port = miniport { |
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snd $otherport, reply => $port; |
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}; |
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1.10 |
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=cut |
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1.22 |
sub port(;&) { |
328 |
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my $id = "$UNIQ." . $ID++; |
329 |
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my $port = "$NODE#$id"; |
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331 |
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if (@_) { |
332 |
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my $cb = shift; |
333 |
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$PORT{$id} = sub { |
334 |
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local $SELF = $port; |
335 |
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eval { |
336 |
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&$cb |
337 |
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and kil $id; |
338 |
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}; |
339 |
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_self_die if $@; |
340 |
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}; |
341 |
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} else { |
342 |
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my $self = bless { |
343 |
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id => "$NODE#$id", |
344 |
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}, "AnyEvent::MP::Port"; |
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$PORT_DATA{$id} = $self; |
347 |
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$PORT{$id} = sub { |
348 |
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local $SELF = $port; |
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350 |
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eval { |
351 |
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for (@{ $self->{rc0}{$_[0]} }) { |
352 |
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$_ && &{$_->[0]} |
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&& undef $_; |
354 |
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} |
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for (@{ $self->{rcv}{$_[0]} }) { |
357 |
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$_ && [@_[1 .. @{$_->[1]}]] ~~ $_->[1] |
358 |
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&& &{$_->[0]} |
359 |
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&& undef $_; |
360 |
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} |
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362 |
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for (@{ $self->{any} }) { |
363 |
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$_ && [@_[0 .. $#{$_->[1]}]] ~~ $_->[1] |
364 |
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&& &{$_->[0]} |
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&& undef $_; |
366 |
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} |
367 |
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}; |
368 |
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_self_die if $@; |
369 |
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}; |
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} |
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1.10 |
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1.22 |
$port |
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1.10 |
} |
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1.22 |
=item reg $portid, $name |
376 |
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1.8 |
|
377 |
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1.22 |
Registers the given port under the name C<$name>. If the name already |
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exists it is replaced. |
379 |
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1.8 |
|
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1.22 |
A port can only be registered under one well known name. |
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1.8 |
|
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1.22 |
A port automatically becomes unregistered when it is killed. |
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1.8 |
|
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=cut |
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1.22 |
sub reg(@) { |
387 |
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my ($portid, $name) = @_; |
388 |
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1.8 |
|
389 |
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1.22 |
$REG{$name} = $portid; |
390 |
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} |
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1.18 |
|
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1.22 |
=item rcv $portid, tagstring => $callback->(@msg), ... |
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1.3 |
|
394 |
root |
1.22 |
=item rcv $portid, $smartmatch => $callback->(@msg), ... |
395 |
root |
1.3 |
|
396 |
root |
1.22 |
=item rcv $portid, [$smartmatch...] => $callback->(@msg), ... |
397 |
root |
1.3 |
|
398 |
root |
1.22 |
Register callbacks to be called on matching messages on the given port. |
399 |
root |
1.3 |
|
400 |
|
|
The callback has to return a true value when its work is done, after |
401 |
|
|
which is will be removed, or a false value in which case it will stay |
402 |
|
|
registered. |
403 |
|
|
|
404 |
root |
1.22 |
The global C<$SELF> (exported by this module) contains C<$portid> while |
405 |
|
|
executing the callback. |
406 |
|
|
|
407 |
|
|
Runtime errors wdurign callback execution will result in the port being |
408 |
|
|
C<kil>ed. |
409 |
|
|
|
410 |
root |
1.3 |
If the match is an array reference, then it will be matched against the |
411 |
|
|
first elements of the message, otherwise only the first element is being |
412 |
|
|
matched. |
413 |
|
|
|
414 |
|
|
Any element in the match that is specified as C<_any_> (a function |
415 |
|
|
exported by this module) matches any single element of the message. |
416 |
|
|
|
417 |
|
|
While not required, it is highly recommended that the first matching |
418 |
|
|
element is a string identifying the message. The one-string-only match is |
419 |
|
|
also the most efficient match (by far). |
420 |
|
|
|
421 |
|
|
=cut |
422 |
|
|
|
423 |
|
|
sub rcv($@) { |
424 |
root |
1.22 |
my ($noderef, $port) = split /#/, shift, 2; |
425 |
root |
1.3 |
|
426 |
root |
1.22 |
($NODE{$noderef} || add_node $noderef) == $NODE{""} |
427 |
|
|
or Carp::croak "$noderef#$port: rcv can only be called on local ports, caught"; |
428 |
|
|
|
429 |
|
|
my $self = $PORT_DATA{$port} |
430 |
|
|
or Carp::croak "$noderef#$port: rcv can only be called on message matching ports, caught"; |
431 |
|
|
|
432 |
|
|
"AnyEvent::MP::Port" eq ref $self |
433 |
|
|
or Carp::croak "$noderef#$port: rcv can only be called on message matching ports, caught"; |
434 |
|
|
|
435 |
|
|
while (@_) { |
436 |
|
|
my ($match, $cb) = splice @_, 0, 2; |
437 |
|
|
|
438 |
|
|
if (!ref $match) { |
439 |
|
|
push @{ $self->{rc0}{$match} }, [$cb]; |
440 |
|
|
} elsif (("ARRAY" eq ref $match && !ref $match->[0])) { |
441 |
|
|
my ($type, @match) = @$match; |
442 |
|
|
@match |
443 |
|
|
? push @{ $self->{rcv}{$match->[0]} }, [$cb, \@match] |
444 |
|
|
: push @{ $self->{rc0}{$match->[0]} }, [$cb]; |
445 |
|
|
} else { |
446 |
|
|
push @{ $self->{any} }, [$cb, $match]; |
447 |
|
|
} |
448 |
root |
1.3 |
} |
449 |
root |
1.2 |
} |
450 |
|
|
|
451 |
root |
1.22 |
=item $closure = psub { BLOCK } |
452 |
root |
1.2 |
|
453 |
root |
1.22 |
Remembers C<$SELF> and creates a closure out of the BLOCK. When the |
454 |
|
|
closure is executed, sets up the environment in the same way as in C<rcv> |
455 |
|
|
callbacks, i.e. runtime errors will cause the port to get C<kil>ed. |
456 |
|
|
|
457 |
|
|
This is useful when you register callbacks from C<rcv> callbacks: |
458 |
|
|
|
459 |
|
|
rcv delayed_reply => sub { |
460 |
|
|
my ($delay, @reply) = @_; |
461 |
|
|
my $timer = AE::timer $delay, 0, psub { |
462 |
|
|
snd @reply, $SELF; |
463 |
|
|
}; |
464 |
|
|
}; |
465 |
root |
1.3 |
|
466 |
root |
1.8 |
=cut |
467 |
root |
1.3 |
|
468 |
root |
1.22 |
sub psub(&) { |
469 |
|
|
my $cb = shift; |
470 |
root |
1.3 |
|
471 |
root |
1.22 |
my $port = $SELF |
472 |
|
|
or Carp::croak "psub can only be called from within rcv or psub callbacks, not"; |
473 |
root |
1.1 |
|
474 |
root |
1.22 |
sub { |
475 |
|
|
local $SELF = $port; |
476 |
root |
1.2 |
|
477 |
root |
1.22 |
if (wantarray) { |
478 |
|
|
my @res = eval { &$cb }; |
479 |
|
|
_self_die if $@; |
480 |
|
|
@res |
481 |
|
|
} else { |
482 |
|
|
my $res = eval { &$cb }; |
483 |
|
|
_self_die if $@; |
484 |
|
|
$res |
485 |
|
|
} |
486 |
|
|
} |
487 |
root |
1.2 |
} |
488 |
|
|
|
489 |
root |
1.8 |
=back |
490 |
|
|
|
491 |
|
|
=head1 FUNCTIONS FOR NODES |
492 |
|
|
|
493 |
|
|
=over 4 |
494 |
root |
1.2 |
|
495 |
root |
1.29 |
=item become_public $noderef |
496 |
root |
1.8 |
|
497 |
|
|
Tells the node to become a public node, i.e. reachable from other nodes. |
498 |
|
|
|
499 |
root |
1.29 |
The first argument is the (unresolved) node reference of the local node |
500 |
|
|
(if missing then the empty string is used). |
501 |
|
|
|
502 |
|
|
It is quite common to not specify anything, in which case the local node |
503 |
|
|
tries to listen on the default port, or to only specify a port number, in |
504 |
|
|
which case AnyEvent::MP tries to guess the local addresses. |
505 |
root |
1.2 |
|
506 |
root |
1.8 |
=cut |
507 |
root |
1.1 |
|
508 |
root |
1.4 |
=back |
509 |
|
|
|
510 |
|
|
=head1 NODE MESSAGES |
511 |
|
|
|
512 |
root |
1.5 |
Nodes understand the following messages sent to them. Many of them take |
513 |
|
|
arguments called C<@reply>, which will simply be used to compose a reply |
514 |
|
|
message - C<$reply[0]> is the port to reply to, C<$reply[1]> the type and |
515 |
|
|
the remaining arguments are simply the message data. |
516 |
root |
1.4 |
|
517 |
root |
1.29 |
While other messages exist, they are not public and subject to change. |
518 |
|
|
|
519 |
root |
1.4 |
=over 4 |
520 |
|
|
|
521 |
|
|
=cut |
522 |
|
|
|
523 |
root |
1.22 |
=item lookup => $name, @reply |
524 |
root |
1.3 |
|
525 |
root |
1.8 |
Replies with the port ID of the specified well-known port, or C<undef>. |
526 |
root |
1.3 |
|
527 |
root |
1.7 |
=item devnull => ... |
528 |
|
|
|
529 |
|
|
Generic data sink/CPU heat conversion. |
530 |
|
|
|
531 |
root |
1.4 |
=item relay => $port, @msg |
532 |
|
|
|
533 |
|
|
Simply forwards the message to the given port. |
534 |
|
|
|
535 |
|
|
=item eval => $string[ @reply] |
536 |
|
|
|
537 |
|
|
Evaluates the given string. If C<@reply> is given, then a message of the |
538 |
root |
1.5 |
form C<@reply, $@, @evalres> is sent. |
539 |
|
|
|
540 |
|
|
Example: crash another node. |
541 |
|
|
|
542 |
|
|
snd $othernode, eval => "exit"; |
543 |
root |
1.4 |
|
544 |
|
|
=item time => @reply |
545 |
|
|
|
546 |
|
|
Replies the the current node time to C<@reply>. |
547 |
|
|
|
548 |
root |
1.5 |
Example: tell the current node to send the current time to C<$myport> in a |
549 |
|
|
C<timereply> message. |
550 |
|
|
|
551 |
|
|
snd $NODE, time => $myport, timereply => 1, 2; |
552 |
|
|
# => snd $myport, timereply => 1, 2, <time> |
553 |
|
|
|
554 |
root |
1.2 |
=back |
555 |
|
|
|
556 |
root |
1.26 |
=head1 AnyEvent::MP vs. Distributed Erlang |
557 |
|
|
|
558 |
root |
1.27 |
AnyEvent::MP got lots of its ideas from distributed erlang (erlang node |
559 |
|
|
== aemp node, erlang process == aemp port), so many of the documents and |
560 |
|
|
programming techniques employed by erlang apply to AnyEvent::MP. Here is a |
561 |
|
|
sample: |
562 |
|
|
|
563 |
|
|
http://www.erlang.se/doc/programming_rules.shtml |
564 |
|
|
http://erlang.org/doc/getting_started/part_frame.html # chapters 3 and 4 |
565 |
|
|
http://erlang.org/download/erlang-book-part1.pdf # chapters 5 and 6 |
566 |
|
|
http://erlang.org/download/armstrong_thesis_2003.pdf # chapters 4 and 5 |
567 |
|
|
|
568 |
|
|
Despite the similarities, there are also some important differences: |
569 |
root |
1.26 |
|
570 |
|
|
=over 4 |
571 |
|
|
|
572 |
|
|
=item * Node references contain the recipe on how to contact them. |
573 |
|
|
|
574 |
|
|
Erlang relies on special naming and DNS to work everywhere in the |
575 |
|
|
same way. AEMP relies on each node knowing it's own address(es), with |
576 |
|
|
convenience functionality. |
577 |
|
|
|
578 |
root |
1.27 |
This means that AEMP requires a less tightly controlled environment at the |
579 |
|
|
cost of longer node references and a slightly higher management overhead. |
580 |
|
|
|
581 |
root |
1.26 |
=item * Erlang uses processes and a mailbox, AEMP does not queue. |
582 |
|
|
|
583 |
|
|
Erlang uses processes that selctively receive messages, and therefore |
584 |
|
|
needs a queue. AEMP is event based, queuing messages would serve no useful |
585 |
|
|
purpose. |
586 |
|
|
|
587 |
|
|
(But see L<Coro::MP> for a more erlang-like process model on top of AEMP). |
588 |
|
|
|
589 |
|
|
=item * Erlang sends are synchronous, AEMP sends are asynchronous. |
590 |
|
|
|
591 |
|
|
Sending messages in erlang is synchronous and blocks the process. AEMP |
592 |
|
|
sends are immediate, connection establishment is handled in the |
593 |
|
|
background. |
594 |
|
|
|
595 |
|
|
=item * Erlang can silently lose messages, AEMP cannot. |
596 |
|
|
|
597 |
|
|
Erlang makes few guarantees on messages delivery - messages can get lost |
598 |
|
|
without any of the processes realising it (i.e. you send messages a, b, |
599 |
|
|
and c, and the other side only receives messages a and c). |
600 |
|
|
|
601 |
|
|
AEMP guarantees correct ordering, and the guarantee that there are no |
602 |
|
|
holes in the message sequence. |
603 |
|
|
|
604 |
|
|
=item * In erlang, processes can be declared dead and later be found to be |
605 |
|
|
alive. |
606 |
|
|
|
607 |
|
|
In erlang it can happen that a monitored process is declared dead and |
608 |
|
|
linked processes get killed, but later it turns out that the process is |
609 |
|
|
still alive - and can receive messages. |
610 |
|
|
|
611 |
|
|
In AEMP, when port monitoring detects a port as dead, then that port will |
612 |
|
|
eventually be killed - it cannot happen that a node detects a port as dead |
613 |
|
|
and then later sends messages to it, finding it is still alive. |
614 |
|
|
|
615 |
|
|
=item * Erlang can send messages to the wrong port, AEMP does not. |
616 |
|
|
|
617 |
|
|
In erlang it is quite possible that a node that restarts reuses a process |
618 |
|
|
ID known to other nodes for a completely different process, causing |
619 |
|
|
messages destined for that process to end up in an unrelated process. |
620 |
|
|
|
621 |
|
|
AEMP never reuses port IDs, so old messages or old port IDs floating |
622 |
|
|
around in the network will not be sent to an unrelated port. |
623 |
|
|
|
624 |
|
|
=item * Erlang uses unprotected connections, AEMP uses secure |
625 |
|
|
authentication and can use TLS. |
626 |
|
|
|
627 |
|
|
AEMP can use a proven protocol - SSL/TLS - to protect connections and |
628 |
|
|
securely authenticate nodes. |
629 |
|
|
|
630 |
root |
1.28 |
=item * The AEMP protocol is optimised for both text-based and binary |
631 |
|
|
communications. |
632 |
|
|
|
633 |
|
|
The AEMP protocol, unlike the erlang protocol, supports both |
634 |
|
|
language-independent text-only protocols (good for debugging) and binary, |
635 |
|
|
language-specific serialisers (e.g. Storable). |
636 |
|
|
|
637 |
|
|
It has also been carefully designed to be implementable in other languages |
638 |
|
|
with a minimum of work while gracefully degrading fucntionality to make the |
639 |
|
|
protocol simple. |
640 |
|
|
|
641 |
root |
1.26 |
=back |
642 |
|
|
|
643 |
root |
1.1 |
=head1 SEE ALSO |
644 |
|
|
|
645 |
|
|
L<AnyEvent>. |
646 |
|
|
|
647 |
|
|
=head1 AUTHOR |
648 |
|
|
|
649 |
|
|
Marc Lehmann <schmorp@schmorp.de> |
650 |
|
|
http://home.schmorp.de/ |
651 |
|
|
|
652 |
|
|
=cut |
653 |
|
|
|
654 |
|
|
1 |
655 |
|
|
|